| A Shared Fate
Introduction
Toxins In Marine Mammals An Impending Global Catastrophe
Dolphins Are Not Food - Health Consequences for Japanese
Consumers
Cancer In Dolphins - An Emerging Threat
Multiple Myeloma in Dolphins
POPs Fact Sheet
Mercury Fact Sheet
The Inability Of Dolphins To Metabolize Certain PCBs
CYP1A1 - A Telltale Gene
The Striking Similarity Between Human and Dolphin
Genomes
The International Myeloma Foundation Identifies
Potential Link Between Genetic Pathways And Environmental Risks For Myeloma
New Bioaccumulations of Toxins in Resident Coastal Dolphins
Signal Dangers of Human Myeloma
Multiple Myeloma, Clusters, Clues and Dioxin
INTRODUCTION
The growing presence of toxic chemicals in the marine environment presents
a crisis unlike any ever faced on this planet. Vast quantities of toxic
chemicals enter the waterways and oceans of the world each day and accumulate
then bio-magnify in the marine food chain. In a time when we have reduced
the number of large pelagic fish by ninety percent and the bio-mass of
the oceans by seventy percent, we are poisoning much of the living marine
resources that remain. This has staggering global implications for ocean
life and human health.
A level of 100 ppm of mercury has been found in a bottlenose dolphin killed for food in Japan – a level more than 100 times that accepted by Japanese health authorities
There are many ways by which humans absorb, ingest or inhale dangerous
chemicals. We intend to show in this report that fish, contaminated by
organochlorines and heavy metals, are a newly recognized delivery system
for chemicals which may cause a range of negative impacts on human health,
including cancer, suppressed immune function and endocrine disruption
which affects fertility.
Dolphins, toothed whales, large tuna and swordfish are among the marine
creatures with highest levels of contamination because they feed at the
apex of the food chain.
This report will document many, but by no means all, the locations where
chemical toxicants have been found in marine mammals. Marine mammals feed
at the top of the ocean food chain and thus are sentinels of the health
of the waters in which they swim. Because humans eat many of the same
fish as marine mammals we are well advised to be aware of the plight of
marine mammals around the world. We are only one step removed from them
only because we eat fewer fish than they.
Those eating marine mammals are leveraging the concentrations of toxins
they ingest – a top predator (human) eating another top predator
(a dolphin). We document the levels of contaminants in dolphins killed
and eaten at Taiji, Japan. This is among the last of the villages where
dolphins are hunted and where the meat is commonly eaten. We find that
to have to use evidence of contamination levels in dolphins as a way of
ending one of the most barbaric hunts of wild animals on earth to be tragically
ironic.
One dolphin eater at Taiji was found to have more than 30 ppm of mercury in his body. A medical specialist advised that he be hospitalized immediately.
Though industrialized nations banned many persistent organic pollutants (POPs) three decades ago, their persistence plagues marine mammals and, increasingly, human beings worldwide. Today overwhelming evidence indicates that heavy metals such as mercury and persistent organic pollutants such as polychlorinated biphenyls (PCBs), dioxins and more recently PBDEs (flame
retardants) have an adverse impact on reproductive health, immune and
endocrine function and are carcinogenic for marine mammals and human beings.
Carcinogens are present in the environment of the St. Lawrence Estuary
Belugas. Sediments of the Saginaw River, part of Beluga habitat, contain
500 – 4500 ppb of total PAHs dry weight.
Scientists have been finding higher and higher levels of man-made chemicals
in marine mammals.In recent years marine mammals have been victims of
mass mortalities and alarming population declines. These events have caused
marine mammal science to expand their studies of the impact of chemically
induced immune suppression, which is emerging as a contributing factor
in epizootic events, condemning marine mammals to death from viral agents
that are common in the environment and normally harmless.
During the late winters of 2007 and 2008 in two separate unusual mortality events (UME) more than two hundred bottlenose dolphins washed ashore near
Galveston, Texas. The cause of this UME is as yet unknown.
In a report that stunned many, the February 2008 issue of Science reported,
“The impact of humans has now reached every square mile of earth’s
oceans and strongly impacted 40% of marine ecosystems. The implications
are ominous for ocean creatures and humans alike. “
Some 100,000 synthetic chemicals are in use today around the world with
another 1,000 being introduced into the environment each year. More than
90% have never been tested for their effects on human health. There is
abundant evidence that many of these chemicals have serious, even deadly
impacts on wildlife and humans.
Chemicals enter the marine environment in many ways – fertilizer
run off and use of pesticides in agriculture and home gardening and maintenance;
industrial waste, dumping and airborne emissions, even chemicals such
as flame retardants used in everyday products are carried around the globe
by wind and ocean currents.
San Francisco Bay harbor seals have some of the highest levels of PBDEs
ever recorded. A doubling time of 1.8 years was reported in blubber of
harbor seals from San Francisco Bay between 1989 – 1998.
The contaminants in our waters are not limited to heavy metals and organochlorines.
When drinking water for some 41-million Americans was tested by the Associated
Press during 2007, pharmaceuticals were found in alarming quantities.
Those reported include antibiotics, mood stabilizers and six hormones.
Tests were conducted in the nation’s 50 largest cities and smaller
water providers in all 50 states.
A major focus of BlueVoice.org’s work is to identify the locations
in which marine mammals have displayed high levels of toxic chemicals
or been victims of anomalous mortality events. In many of these areas,
we see human cancer clusters. We are collaborating with experts in human
medicine to identify correlates between contamination in marine mammals
and diseases, including cancers, in humans.
Scientists working at Texas A & M have found that the dolphin genome
and the human genome as “basically the same.”
Dr. Gregory Bossart of the Harbor Branch Research Institute and his
colleagues have found orogenital neoplasia in Atlantic bottlenose dolphins
in Florida. Lingual papillomas and squamous cell carcinoma and genital papillomas have also been found in Indian River dolphins.
It is important to remember that clean fish are an important component
of a healthy diet, providing Omega 3 fatty acids and many other benefits.
But that is ONLY TRUE if the fish are relatively free of contamination.
While fish with high levels of Omega 3 fatty acids are regarded at heart
healthy, they are not so when they contain high levels of mercury which
disrupts the nervous system’s control of the heart. They then become
a serious detriment to the hearts of both humans and marine mammals.
In the spring of 1987 bottlenose dolphins began washing up on the coast
of New Jersey. This enormous and highly alarming die-off of hundreds –
perhaps thousands of dolphins – has never been satisfactorily explained.
The Center for Disease Control and Prevention conducts a large, ongoing
survey that has found 148 chemicals in Americans of all ages, including
lead, mercury, dioxins and PCBs.
Other scientists have detected antibacterial agents from liquid soaps
in breast milk, infants’ cord blood and the urine of young girls.
Estrogen excreted by women taking birth control pills has proven to alter
the sex of fish. In 2005, the Environmental Working group found an average
of 200 chemicals in the cord blood of 10 newborns, including carcinogens
and neurotoxins.
Chemicals such as PCBs can be virtually undetectable in water but magnify
exponentially up the food chain so that a top predator may have 25-million
times the concentrations found in the water it lives in. These toxicants
are lipophylic and concentrate in the fatty tissues of mammals.
Chemicals present in many pesticides, petroleum products, plastics, and
products such as furniture, computers and baby’s clothing can disrupt
the endocrinal or hormonal systems of mammals. These chemicals are known
as xenoestrogens because they mimic the action of naturally produced estrogens.
Examples of hermaphroditism have been found in fish in the U.K. in Polar
bears in Svalbard and alligators with diminutive penises have been reported
in Florida.
Man-made chemical pollutants have now made their way into the deep-sea
food web contaminating squids and octopods. These species are food for
many deep-diving toothed whales and dolphins as well as other predators.
In a study to be published in the journal Marine Pollution Bulletin,
Michael Vecchione of NOAA Fisheries’ National Systematics Laboratory
et al report finding chemical contaminants in nine species of cephalopods.
“It was surprising to find measurable and sometimes high amounts
of toxic pollutants in such a deep and remote environment,” Vecchione
said. Among the chemicals detected were tributyltin (TBT), polychlorinated
biphenyls (PCBs), brominated diphenyl ethers (BDEs), and dichlorodiphenyl-trichloroethane
(DDT).
Cephalopods are the primary food for 28 species of odontocetes, the sub-order
of cetaceans that have teeth and include beaked, sperm, killer and beluga
whales and narwhals as well as dolphins and porpoises.
This report is part of an effort at prevention of cancers such as multiple myeloma and other B cell lymphomas – cancers that have been clearly
proven to be caused by exposure to toxic chemicals. To date prevention
of cancer has largely been ignored in favor of treatment.
We call on government to address the introduction of toxic chemicals
into our environment in a manner diametrically opposite to the way we
now do it.
At this time there is virtually no requirement for testing of chemicals
before they are put into use. If public policy operated under a precautionary
principle then any indication of harm, rather than retroactive proof of
harm, would trigger regulatory action. Today chemicals can be put into
the air, waterways, baby clothing and thus into the bloodstreams of all
living creatures without prior proof that they are safe.
We make no pretense that the information in this document is exhaustive.
Indeed it is merely suggestive of the dreadful crisis we face from heavy
metal and organochlorine contamination of the environment. We invite additions,
and if necessary, correction to this report.
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TOXINS IN MARINE MAMMALS AN IMPENDING GLOBAL CATASTROPHE
This paper documents some of the locations in which marine mammals have
displayed high levels of toxic chemicals or been victims of disease or unusual mortality events. It is clear from both the severity and frequency
of such events that marine mammals worldwide face major threats to their
health and in some populations decline or extinction.
In addition to concern for the marine mammals and health of the oceans
we are increasingly aware of the adverse impact high levels of toxins
in the oceans are having on human populations, including mercury poisoning,
endocrine disruption and cancer. We have launched a research project to
identify areas around the world where marine mammals show high toxic levels
in proximity to human populations that eat the same fish as those marine
mammals.
We are collaborating with cancer specialists to identify correlations
between contamination levels in marine mammals and cancers in humans who
eat fish from the same area.
This is by no means a complete listing of relevant locations and events
and we invite contributions to it.
CALIFORNIA
San Francisco Bay harbor seals have high levels of Polybrominated diphenyl ethers (PBDEs) – flame retardants. A doubling time of 1.8 years was reported in blubber of harbor seals from SFB between 1989 – 1998.
Jianwen She et al, of the Hazardous Materials Laboratory, California
Department of Toxic Substances Control in 2002 analyzed samples from 11
archived harbor seals (Phoca vitulina Richardsi) from the San Francisco
Bay and breast adipose tissue samples from 23 women. The levels of PBDEs
in human tissue samples were in the low ng/g fat range, with PBDEs 47,
153, 154, 99, and 100 as the major congeners. Average ?PBDEs (86 ng/g
fat) in these California women are the highest human levels reported to
date. The PBDEs measured in harbor seal blubber were the same major congeners
as those measured in the human tissues. PBDE 47 was the highest among
all congeners measured in both human tissue and seal blubber samples.
The concentrations of PBDEs in harbor seals in the San Francisco Bay have
increased dramatically over the past decade, with current levels among
the highest reported for this species.
Harbor seals can be used to identify regional contamination hotspots.
In California Sea Lions high levels of DDTs and polychlorinated biphenyls (PCBs) in blubber have been associated with cancer and reproductive failure.
Substantial organochlorine (OC) burdens, especially DDTs, are transferred
from female sea lions to their fetuses in utero.
Urogenital cancer is endemic in California sea lions (CSL). A gamma herpes
virus has been identified in 100% of urogenital carcinomas in three different
studies. There is a statistical association of cancer in females and the
presence of beta hemolytic Streptococus. There is a statistical association
between contaminants, particularly PCBs, and urogenital cancer incidence.
Urogenital carcinomas in CSLs may involve interaction between a venereal
herpes virus, bacterial flora and POPs.
Salmonella bacteria causes diarrhea in animals and humans. A number of
fecal pathogens have been identified in California marine mammals. Salmonella
prevalence averages 4% in sea lions, harbor seals. Elephant seals and
sea otters, as well as many bird species. Marine Mammal Salmonella, Miller
et al.
Harmful Algal Blooms (HABs) There is strong evidence
that marine mammal strandings along the coast of California are caused
by harmful algal blooms. One of the main culprits is domoic acid poisoning.
Domoic acid is a powerful neurotoxin produced by a single-celled algae
of the genus Pseudo-nitzschia. It accumulates in shellfish and fish that
feed on the algae, such as anchovies and sardines.
Marine biotoxins resulting from HABs have been shown to be lethal to
dolphins and other marine mammals that have ingested contaminated fish.
HABs often involve brevitoxin, a neurotoxin produced by some species of dinoflagellate such as, Karenia brevis and Ptychodiscus brevis. Brevitoxin is associated with a growing number of 'red tide' events around the world.
In 1998, the first confirmed domoic acid poisoning of marine mammals
occurred on the California coast. During a month long period, 70 California
sea lions stranded along the central California coast near San Luis Obispo
– all suffered from the clinical symptoms of the poisoning, which
include head weaving, tremors and convulsions. The majority of the affected
animals were adult females of which 50 percent were pregnant. No adult
males were affected. Two years later a similar outbreak occurred in the
same region when 187 sea lions stranded with the poisoning. More than
half of the sea lions affected with domoic acid poisoning died in both
instances.
The origin of the domoic acid responsible for this mortality event was
a bloom of P. australis that developed in Monterey Bay in May of 1998.
Anchovies collected during the peak of the bloom had high levels of domoic
acid in their tissues. “California sea lions are high level predators,
feeding on species that often enter the human seafood market such as anchovies,
sardines, salmon and squid,” said Dr. Frances Gulland of the California
Marine Mammal Center.
“These sub-lethal effects of domoic acid on California sea lions
are likely to be similar to effects that could occur in humans if they
were to be exposed to similar levels of this toxin by eating contaminated
seafood.” – Dr. Frances Gulland
The Marine Mammal Center in Sausalito, California has been one of the
leading organizations tracking the strandings of Sea Lions and aiding
in their recovery and re-introduction to the wild.
Outbreaks continued in southern and central California waters with nearly
1,000 sea lions affected in 2005.
In 2007 blooms of algae which produce the neurotoxin domoic acid, first
appeared in southern California early in the spring and then moved north
along the Central Coast. Hundreds of seabirds and marine mammals died.
The domoic acid levels in Southern California have been even higher than
those detected in Monterey Bay. Large numbers of marine animals have been
affected, including dolphins.
In humans, consumption of seafood contaminated with the toxin causes
amnesic shellfish poisoning.
1987-88 EAST COAST OF USA
Beginning in the spring of 1987 bottlenose dolphins began washing up on
the coast of New Jersey. This enormous and highly alarming die-off of
hundreds of dolphins (in reality the number of deceased dolphins is certainly
vastly higher than the number of stranded dolphins would indicate. Many
dolphins were lost at sea and never counted). The strandings progressed
from New Jersey south along the Atlantic seaboard finally ending near
Cape Canaveral, Florida in early 1988. By one estimate at least 2,500
dolphins were lost. Alarmingly high levels of contaminants were found
in many of the stranded dolphins. After months of study an expert contracted
by the US government concluded that the die-off was the result of red
tide generated brevitoxin. Many scientists, pointing to the high levels
of toxins in many of the dolphins necropsied, disputed this conclusion
vigorously and called that finding a cover up.
FLORIDA
Sarasota Bay. Trace elements of methyl mercury have been found
in bottlenose dolphins in this body of water. High brominated flame retardant (BFRs) concentrations have been detected in dolphins near urban Sarasota
Bay and rural St. Joe Bay in the Florida panhandle. The presence of BFRs
in all dolphin samples indicates contamination is wide spread.
Dr. Randy Wells is quoted in National Geographic Online as saying that
although dolphin numbers in these waters have risen slightly over the
last few decades, scientists are trying to understand why so many firstborn
calves die: Less than a quarter live out their first year, compared with
70 to 80 percent of subsequent births.
One reason may be man-made pollutants and the transfer of chemical contaminants
to calves through milk, according to Wells, a conservation biologist with
the Chicago Zoological Society and director of the Mote Marine Laboratory
for Marine Mammal and Sea Turtle Research in Sarasota. Since 1970, Wells
has led the world's longest-running dolphin study.
Some dolphins in the Sarasota Bay area have pollutant levels among the
highest ever recorded, according to Wells.
East Coast Florida through South Carolina. Several unusual
mortality events have occurred in recent years increasing concern for
the health of bottlenose dolphins along the east coast of the United States.
The heavy metals Aluminium, Chromium, Manganese, Copper, Zinc, Arsenic,
Selenium, Strontium, Rubidium, Molybdenm and Vanadium were all discovered
in the tissues of dolphins. Levels in blood and skin are above levels
thought to be harmful to health.
Indian River, Florida
Dr. Gregory Bossart of the Harbor Branch Research Institute and his colleagues
have been studying dolphins and the ecology of the Indian River Lagoon
(IRL) for nearly two decades. He has found orogenital neoplasia in Atlantic
bottlenose dolphins. Lingual papillomas and squamous cell carcinoma and
genital papillomas have also been found in dolphins of this body of water.
Bossart’s may be the first report of genital papillomas in free
ranging bottlenose dolphins from Atlantic coastal waters.
Comprehensive health examinations were conducted from 2003 – 2004
on 155 bottlenose dolphins during capture-release in the IRL and Charleston,
SC (CHS). Some 30% of IRL dolphins had infectious diseases such as lobomycosis according to Dr. Bossart. Mucocutaneous neoplasia associated with novel
papilloma and herpes viruses were documented in both populations.
The St. Lucie River which flows into the IRL carries significant quantities
of agricultural runoff.
Necropsy and photo identification data on IRL bottlenose dolphins have
shown a high prevalence of infectious and inflammatory diseases of the
skin and other organs.
Mitchum and Bossart et al have compared OC pesticides, PCBs, PBDEs and polycyclic aromatic hydrocarbons (PAHs) levels in dolphins from the IRL
and Charleston, SC (CHS). Mean concentrations of PCBs were similar in
the two locations, highest in male dolphins and lowest in females of reproductive
age. Total DDT was higher for CHS dolphins compared to IRL dolphins. CHS
dolphins had higher PBDEs. The males had among the highest levels of this
chemical ever found in marine mammals.
In an abstract entitled lobomycosis in Atlantic Bottlenose Dolphins from
Indian River Lagoon, Florida, Reif et al report the presence of lobomycosis,
a mycotic infection caused by a yeast-like organism, among bottlenose
dolphins. The prevalence among the dolphins tested from the southern part
of the IRL was 30%. “We report the emergence of a rare fungal disease
in Florida bottlenose dolphins in epidemic proportions. Humans are also
susceptible to Lacazia loboi, a yeast-like organism. “ The report
went on to say that environmental stressors may contribute to the unusually
high prevalence of the disease.
According to Dr. Greg Bossart, there is dolphin pox virus in the Indian
River Lagoon. This doesn’t hurt the animal but points to pathological
stress. 100% of IRL dolphins had pox versus the usual 2% found in dolphins
in other locations.
Florida Panhandle
In 1999 and 2004 there were two unusual mortality events that took the
lives of 227 dolphins in the area of St. Joseph’s Bay. The average
number of dolphins that strand along the panhandle per year is eight.
More than 103 dolphins died in St. Joseph's Bay and the surrounding area
in Florida beginning March 10, 2004. NOAA Fisheries declared an Unusual
Mortality Event for the panhandle on March 17. Several forms of algae
were found in the surrounding waters. In addition, preliminary results
showed domoic acid (a biotoxin produced by Pseudo-nitzschia) and brevetoxin
(a biotoxin produced by Karenia brevis) in samples taken from the dolphins.
Dolphin carcasses that were located (many were not) had been dead for
an extended period prior to recovery making tests for cause of death difficult.
Preliminary results on dolphin tissues from the initial event indicated
the following:
Florida Marine Research Institute (FMRI) scientists detected high concentrations
of brevetoxin in dolphin tissues (stomach, liver, kidney, lung, cerebellum)
and fluids (blood, urine); the highest concentrations of brevetoxins were
found in the animals' stomachs.
The time period for the unusual mortality event (March – April)
corresponds to the timing of similar mortality events in Texas.
Immune panels suggest a high level of parasitic infection and/or compromised
immune response in the St. Joseph Bay population of bottlenose dolphins.
Florida, general
The EPA has listed 16 polycyclic aromatic hydrocarbons (PAHs) as priority
pollutants because of their carcinogenic effects on aquatic organisms.
PAHs have been found around electricity generating plants and in ports
in Florida.
Recently manatees have shown symptoms characteristic of PAH accumulation:
e.g. impaired immune response, prolonged healing times, and eye pathology.
CHARLESTON, SC (CHS) (See Indian River, Florida for paired studies)
CHS dolphins have a higher levels of persistent chemicals, including emerging
chemicals such as perflourinated compounds and PBDEs and higher levels
of resistance to antibiotics (70%) than IRL dolphins.
Perflourinated compounds (PFAs) are persistent, bio-accumulating contaminants
used in stain repellants, paper protectors, paint and polishes. High concentrations
have been detected in plasma of dolphins in Charleston, SC and Delaware
Bay, NJ.
Antibiotic resistant E.coli were found in wild dolphins in Florida and
South Carolina. The widespread use of antibiotics in humans, pets and
agriculture may lead to the development of multi-drug resistant bacteria.
Most antibiotics tested have been shown to be persistent. Resistant genes
are readily transmitted creating the potential for establishment of resistant
bacteria within aquatic life. The most common bacteria to which dolphins
were resistant were Ampicillin, Amoxicillin, Penicillin, Cephalothin,
Cefoxitin, Erythromycin, Trimethoprim, Sulphiazol, and Osytetracycline.
Aquatic Mammals, 1/1/07, Bemiss, Bossart, et. al.
When drinking water was tested by the Associated Press for some 41-million
Americans, pharmaceuticals including antibiotics, mood stabilizers and
sex hormones were found. Tests were conducted in the nation’s 50
largest cities and smaller water providers in all 50 states.
Rehtanz, Bossart et al reported in 2005 the first known case of cetacean
papilloma virus has been detected in a bottlenose dolphins at CHS.
GULF OF MAINE
Susan Shaw, founder of the nonprofit Marine Environmental Research Institute
(MERI) in Blue Hill, Maine, which conducts scientific research and education
on the impacts of pollution on marine life reported findings at the Marine
Mammal Society Conference in Cape Town, South Africa in December, 2007.
Her research on northwestern Atlantic harbor seals shows that toxic chemical
levels, especially in pups, are as high as any in the world.
According to Dr. Shaw, “Over the past three years this population
has experienced recurring disease outbreaks and high mortality rates.
While the specific disease agent is unclear, our studies show that these
seals carry high levels of PBDEs, PCBs, and other chemicals in their tissues
that may be compromising their immune responses.”
This population is affected by recurring epizootics and mass mortalities.
Some of the young seals are carrying up to 4-thousand ppm of PBDEs in
fatty tissues. PCB levels are as high as 60 ppm in the young animals.
Their toxic equivalency for Dioxin like toxicity is also fairly high
in the 200 ppt lipid weight range. Also high levels of polyflourinated
compounds have been found in these seals.
CAPE MAY, NJ
Hepatic panels suggest impaired liver function for many dolphins sampled
near Cape May, NJ
TEXAS
Unusual mortality events have occurred along the Texas coast with alarming
frequency. Most recently in 2007 and 2008 during March and April. In 2008
116 bottlenose dolphins were recovered in the Galveston area. Because
the dolphins were generally in a state of advanced decomposition when
found the cause of death could not be attributed. However there was no
indication the deaths were the result of fisheries interaction. Traces
of domoic acid were found in the three freshest dolphins from 2007. D.
Cowan, a pathologist with the Texas Marine Mammal Stranding Network, suggested
that brevitoxin was involved and warned that this could be harmful to
humans.
WESTERN NORTH ATLANTIC AND GULF OF MEXICO
The brominated flame retardant (BFR) and hexabromocyclodocane (HBCD) are
products still in use with environmental release levels rivaling that
of PCBs prior to its discontinuation. PBDEs are toxicologically similar
to PCBs, which were banned decades ago, though little is known about HBCD
toxicity. PBDE concentrations are ten-fold greater and increasing more
rapidly in Americans than in Western Europe where many of the brominated
chemicals have been banned.
WASHINGTON, SEATTLE
The killer whales inhabiting Puget Sound and surrounding waters are some
of the best-known and most beloved marine mammals on earth. The identities
of all members of the pod are known; in some cases the family tree can
be identified going back decades.
These orca may also be the most contaminated marine mammals on earth.
And from 1995 – 2000 ten of the males in J, K, and L pods died.
While there is no absolute proof that they died from contaminants such
as PCBs, their carcasses did contain astronomical levels of these deadly
toxins.
According to Dr. Ken Balcomb, “We’ve attributed most of the
mortality to the PCB levels in the tissues. Their immune systems are depressed,
much like AIDs, so they don’t defend themselves against common bacteria.
And also their reproductive systems don’t develop.” Females
survive better than males because when a mother orca nurses her calf she
offloads huge amounts of chemicals such as PCBs that are stored in her
lipid rich milk. Often first-born calves do not survive. But second and
third born survive after the mother is unburdened of much of her toxic
load.
Flame retardants used worldwide in manufacturing vehicle parts and computers
have been found in Puget Sound orcas. Traces of industrial strength fire
retardant have also been detected in wild and farm raised salmon.
Harbor seals in Puget Sound carry seven times the levels of PCBs as their
counterparts in the Straights of Georgia, BC, Canada. Levels of PBDEs
are approaching those of PCBs, indicating a significant new chemical concern
for these marine mammals.
EASTERN NORTH PACIFIC
Using blubber and remote biopsy samples, organochlorine profiles were
correlated to the prey species of three different groups of killer whales
– resident fish eaters, transient mammal eaters and offshore animals
that consume large pelagic fish. Resident fish eaters had low OC contamination
in relation to transient killer whales. OC results for some offshore killer
whales were high, even though they eat fish. This suggests they eat high
trophic level species such as shark or tuna which bio-accumulate contaminants
over long lifetimes.
NORTH PACIFIC OCEAN
Stellar sea lions have undergone a drastic decline in population over
the past three decades, which has led to their being listed as endangered.
The precise reason for this decline is unknown. However PCBs are present
in high concentrations in the environment. High concentrations of POPs
have been found to cause adverse affects in the reproductive and immune
systems of marine mammals. According to Hulck et al in Persistent Organic
Pollutants in Blubber of Male Stellar Sea Lion from Different Locations
in the Northern Pacific Ocean, “Our hypothesis is that the Stellar
sea lion population decline or the failure to recover is due to long term
exposure to POPs. The decine may also be the result of translocation of
their prey species due to changes in water temperature.”
PBDE compounds were found in blubber from seals harvested in the Bering
Sea subsistence harvest in Alaska. Due to their recent introduction PBDEs
are a relatively recent suite of chemicals for concern. Their chemical
structure is similar to PCBs and they are thought to be disruptive of
thyroid function. Results indicate that lower brominated congeners of PBDEs are present in the Bering Sea environment. From PBDE Compounds in
Blubber from Bering Sea Sussistence Harvest of Ice Seals In Alaska, Quackenbush.
CANADA
St. Lawrence Estuary (SLE) Belugas: The Beluga population has dropped
from an estimated 5,000 to a current estimate of 500-600. The SLE Belugas
were protected from hunting by the Canadian government starting in 1980
but so far have shown no sign of recovery.
SLE Belugas are contaminated by PAHs. Levels of epithelial cancer of
the proximal intestine, gastric cancer, gastrointestinal epithelial cancer,
and mammary cancers are high in SLE Beluga.
This is consistent with the hypothesis that PAHs are involved in the
etiology of cancer in these animals. Cancer of the proximal intestine
is rare among all species including humans except in circumstances where
the animal has been exposed to pesticides.
It is frequent in bovine and ovine species exposed to herbicides such
as 2,4-dichlorophenoxyacetic acid. An interaction between a virus and
environmental carcinogenic compounds may be at work in the SLE Belugas.
Particles consistent with papilloma viruses have been observed in a significant
number of carcasses. Other carcinogens are present in the environment
of the SLE Belugas. Benzopyrene has been found in high concentrations
in blue mussels after transplantation into the Saguenay River, part of
the Beluga habitat. Sediments of the Saguenay River contain 500 –
4500 ppb of total PAH dry weight, a concentration level significantly
higher than Osaka harbor where PAH concentrations are 2870 ppb. These
chemicals originate from upstream Aluminum smelters. SLE Belugas feed
in sediments. These observations suggest that SLE Belugas ingest PAHs
in benthic invertebrates (those living at the deepest water level and
in sediment) that may contribute to the elevated rate of digestive tract
cancers in the population. Martineau et al.
Martineau in Cancer in Wildlife reports “The rate of cancer in
the SLE Beluga population is higher than in any other population of wild
terrestrial or aquatic animals”.
Cancer was observed in 27% of adult animals found dead, a percentage
similar to that found in humans. A cancer rate of 163 per 100,000 animals
is much higher than in domestic animals and humans. Environmental toxins
are thought to be a precipitating factor in these cancers. Thirty per
cent of cancers affecting SLE beluga are found in the intestine, close
to the stomach.
The human population living in this area is afflicted by rates of cancer
higher than found in other parts of Quebec and Canada in general. Some
of these cancers are epidemiologically related to PAHs.
The SLE Beluga are also contaminated by heavy metals, PCBs, DDT, and
their metabolites, which can, in some cases be more toxic than the original
chemical.
Gastrointestinal epithelial cancers were the most frequent found in beluga
in the SLE. Martineau, Environmental Health Perspectives
Cetaceans have high levels of CYP1A and low levels of CYP2B. SLE belugas
have elevated levels of both enzymes, probably because CYP are induced
by high levels of PCBs.” Elevated CYP1A levels may trigger intestinal
cancer by activating ingested PAHs into carcinogenic compounds.”
Martineau Environmental Health Perspectives 3/2002
PBDEs were determined in blubber samples of 54 stranded adult beluga
whales between 1988 and 1999 in the St. Lawrence Estuary. The accumulation
of PBDEs in belugas showed exponential increase throughout the time period.
Increasing levels of PBDEs have been reported in human milk during this
same time period. PBDE levels in beluga from the Canadian Arctic sampled
in 1997 was 4% of the levels found in belugas from the SLE between 1997
and 1999. Lebeuf Environmental Science and Technology, 2004
CHILE
Aquaculture activities in the study area generate intense organic enrichment
producing eutrophication and release of antibiotics. Recently skin lesions
have been discovered in marine mammals in this area for the first time.
FAROE ISLANDS
PBDEs in long finned pilot whales from Vestmanna range from 1000 to 5000
ng/g. Citation from Lebeuf paper (16, 49-51). But the levels for pilot
whales from Torshavn are in the same range as beluga in the SLE.
A study published in February 2004 in the Journal of Pediatrics indicated
that higher than usual mercury levels in the blood of mothers in the Faroe
Islands had caused neurological problems in their children.
The island’s residents eat large quantities of very high-mercury
pilot whale meat. The study was supported by the U.S. National Institute
of Environmental Health Sciences, a part of the National Institutes of
Health, and by the European Commission under its Environment and Climate
Research Programme.
HONG KONG
Indo-Pacific Humpback Dolphins
The pesticide DDT showed the highest concentration among the OCs found
in the bodies of the so-called Pink Dolphins of this area and the ratio
of DDT to its breakdown products suggest there may have been a recent
nearby source of DDT into the dolphins’ ecosystem, most likely arriving
down the Pearl River into the Pearl River Estuary. Concentrations of both
DDTs and PCBs showed the typical pattern of increase with age in males.
In females they increased to sexual maturity then decreased as mothers
offloaded the contaminants to their newborns through nursing on the lipid
rich milk. Petroleum Hydrocarbons, polycyclic aromatic hydrocarboins,
organochlorine pesticides and PCBs in Indo-Pacific humpback dolphins from
South China Waters. Leung et al.
Samuel Hung and colleagues have estimated the population of pink dolphins
in the Pearl River Delta to be 1400 individuals while 265 dolphins have
been identified in Hong Kong waters. The habitat is perhaps the fastest
growing industrial hub in the world. PCBs, OCPs (organochlorine pesticides) PAHs and petroleum hydrocarbons (PHCs) are widespread in the region’s
waters.
Concentrations of total PCBs ranged from 11,000 to 41,000 ng/g in the
males to 2413 to 4663 ng/g in females, again showing the pattern of higher
male contamination levels viz females who offload much of their toxic
burden into their first born calf.
A larger proportion of DDT in the blubber samples of dolphins inhabiting
the waters adjacent to south China indicates continuous input of DDT into
the aquatic ecosystem.
PAHs were detected in all dolphins sampled. PAHs known to be carcinogenic
accounted for 16.8%, 44.8% and 27.2% of total PAHs found.
Strandings, mortality and morbidity of Indo-Pacific humpback dolphins
in Hong Kong with emphasis on the role of OC contaminants. Jefferson,
Hung and Lam
Eighty six specimens were necropsied over the period 1995 – 2004.
Many were too badly decomposed to yield information. Six living individuals
were also sampled. A large proportion of the stranded dolphins were young
of the year. DDT was found in highest concentrations, again indicating
there is a contemporary source of DDT contaminating these waters. It was
suspected that that high concentrations of contaminants (especially DDTs
and PCBs) in some specimens may have led (directly or indirectly) to the
deaths of the stranded animals.
ITALY
PCBs were found in the blubber of nine bottlenose dolphins stranded on
the eastern Italian coast. PCB 126 was the major contributor to the estimated
toxic potency of PCBs in the dolphins. The total PCB concentrations ranged
from 3534 to 24375 ng/g wet weight.
JAPAN
See separate document for expanded coverage of toxics in marine mammals
and humans in Japan.
MEDITERRANEAN SEA
Mediterranean cetaceans, particularly odontocetes (toothed whales), accumulate
high concentration of OC contamination. Some OCs are known to be endocrine
disrupting compounds. Marked differences in levels of OCs were found between
fin whales (baleen whales) and odontocetes. Organochlorine levels were
significantly higher in the Stenella dolphin population of the Western
Mediterranean Whale sanctuary than in two other study areas.
Mediterranean striped dolphins show much higher levels of mercury than
those in the Atlantic. Mediterranean prey exhibit high levels of mercury.
Mediterranean bottlenose dolphins had higher levels of mercury than their
Atlantic counterparts. In fact, striped dolphins in the western Mediterranean
have some of the highest levels of POPs of any marine mammals.
G. M. Troisi, K. Haraguchi, M. P.
Simmonds and C. F. Mason. The levels of PCBs and PCB methyl
sulphone metabolites were determined in the blubber of six species of
cetaceans that originated from the Irish Sea and the Aegean Sea (Mediterranean).
Burdens ranging from 2.80 to 27.80 µg g (lipid weight) total PCBs
and 0.03 to 0.58 µg g (lipid weight) total methyl sulphones were
recorded. The highest cetacean methyl sulphone burden (0.58 µg g-1)
was in an Irish Sea harbor porpoise (Phocoena phocoena). Methyl sulphone
isomer formation capacity, as determined by PCBs varied considerably between
species as follows: harbour porpoise (1:10) > pilot whale (Globicephalus
melas), white-sided dolphin (Lagenorhyncus acutus) (1:50) > common
dolphin (Delphinus delphis), Risso's dolphin (Grampus griseus), and striped
dolphin (Stenella coerueoalba), (1:100), and was related to interspecific
variation in PCB methyl sulphone formation capacity.
MEXICO
Sirenians in Mexico all have high levels of Haptaclor, Dieldrin and Mirex.
All are carcinogens. PCBs and OCPs are very high in Chetumal Bay.
NORTH SEA, BALTIC SEA
The 1998 die-off of 20,000 European harbor seals was the largest such
event on record. This mass mortality occurred in a population of 36,000
harbor seals in the North Sea where the seals were killed by phocine distemper
virus (PDV). It has been postulated that high levels of mercury and PCBs
may interact with the PDV.
Teflon (PFOS) is well absorbed but poorly metabolized with a reported
half-life of over eight years. It’s long term toxic effects in marine
mammals are unclear but experimental exposure with land mammals reduced
perinatal survival, and produced hepatotoxicity, thyroid and neurological
impairment. High levels were consistently documented in seals in the Baltic
Sea. Differing geographical locations affected values. Mediterranean bottlenose
dolphins had liver values of 170 – 430 versus Gulf of Mexico at
824. Polar Bears in the Canadian arctic had liver levels as high as 678.
There is evidence these levels are increasing over time. In the Baltic
sea levels in one species of seal increased from 1996 at 86 – 180
to 100 – 384 in 1998. Teflon is clearly another significant contaminant
to be considered as a contributor to population declines in marine species,
which will worsen with its escalating use.
UNITED KINGDOM
Gareth Thomas of Lancaster University et al found Organohalogenated contaminants
in harbor seals from various populations around the British Isles. The
investigation took place in 2003. Seals from the southwest Scottish coast
had the highest levels of PCBs with seals from eastern England having
highest levels of PBDEs. Hyperthyroid effects were correlated with levels
of PBDEs in blubber. The researchers found significantly higher levels
of PCBs, but not other contaminants, in seals that died of Phocine Distemper
Virus than in aninals that survive the epidemic. These PCB levels in dead
seals were above the estimated
threshold for effects on the immune systems of marine mammals.
Cardigan Bay, Wales Considering current regulations
it can be surmised that significant pollutants in UK waters can only be
chemicals that were discharged in years past. persistent organic pollutants (that degrade very slowly) and heavy metals, which do not degrade at all,
can remain a problem for decades, even centuries after release into the
environment.
In Cardigan Bay bottlenose dolphins show significant amounts of PCBs
and some heavy metals. Relatively high levels of organochlorines, or heavy
metals such as mercury, could be producing chronic effects on the health
of the dolphins which inhabit this area. These levels may reduce their
ability to resist disease or reproduce.
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DOLPHINS ARE NOT FOOD - HEALTH CONSEQUENCES FOR JAPANESE CONSUMERS
Toxic Chemicals in Whale and Dolphin Meat in Japan Health Consequences
for Japanese Consumers
Some 18-thousand Dall’s porpoise are killed each year off Northern
Japan. Permits to kill some three thousand dolphins and small whales off
the main island of Honshu are in effect. Most of the dolphins taken are
slaughtered for meat. An increasing number are taken into captivity and
shipped to oceanaria, mostly in Asia.
The recent revelation of extremely high levels of contaminants such as mercury, cadmium and PCBs in dolphin meat has led some Japanese officials,
concerned for the health of the citizenry, to examine the policy of eating
cetaceans.
For some two decades environmentalists in Japan and from western NGOs
have been attempting to stop the brutal slaughter of dolphins and small
whales in a few fishing villages in Japan. Initial efforts were based
on exposing the brutality of the hunts. That has had considerable impact
but has not ended the killing. The revelation of high levels of toxicants
in dolphin meat has led to a decrease in demand for dolphin meat.
Dolphin meat is often mislabeled as whale meat in violation of Japanese
food safety laws. The change of the meat sold in stores from baleen whales,
which are low trophic feeders, to dolphins which are high trophic feeders,
subjects those eating this meat to high levels of heavy metals, such as mercury, and organochlorines like PCBs, dioxins and benzenes.
BlueVoice.org is conducting tests on meat taken from dolphins killed
at Taiji, Japan and sold for human consumption. We are also testing hair
samples of people who eat whale and dolphin meat to check for levels of
contaminants. These tests are conducted in Japanese facilities in consultation
with Japanese doctors and scientists.
The first test conducted in 2008 by BlueVoice.org of meat from a bottlenose
dolphin taken at Taiji revealed mercury at 7.20ppm – eighteen times
higher than the maximum level permitted under Japanese health standards.
Fish caught in Japanese coastal waters average 0.63 – 1.41 pg (pico
grams) of mercury. A test by BlueVoice of fish caught in local waters
and sold in markets in Taiji, Japan during November 2007 showed ten fish
species presented values of .02 ppm to 0.49 ppm of mercury. These are
acceptable levels but do not reflect contamination levels for dolphins
and small whales taken and eaten in Taiji. The bottom line is that the
fish from the Taiji area is safe to eat while dolphin and whale meat is
not.
LEVELS OF MERCURY IN DOLPHIN MEAT
In humans, even low-level mercury poisoning has been found to cause memory
loss, hair loss, fatigue, depression, difficulty concentrating, tremors,
headaches and neurological damage, especially in children. Elevated levels
of mercury can lead to heart disease in humans and marine mammals. Because mercury is hard for the body to eliminate, it bioaccumulates.
As news of contamination levels in dolphins became more widely known
in Japan the Taiji fishing cooperative sought ways to promote the sale
of their product. In an effort to expand the demand, the Taiji fishing
cooperative donated dolphin meat to local schools. Taiji, Japan City Councilman
Junichiro Yamashita learned of the high levels of mercury in the meat
provided to the schools and had samples tested.
The results led him to call dolphin meat served in local schools “toxic
waste” because of the high mercury levels.
Mr. Yamashita has led a successful fight to end the practice of giving
meat from locally caught dolphins to schoolchildren. Yamashita stated
publicly that he and a colleague had found extremely high mercury and methyl mercury levels in samples of meat from pilot whales killed in a
local bay and sold in local stores. Pilot whales are actually large dolphins.
Yamashita and another councilman said they were shocked by the results.
One dolphin sample had 10 times the health ministry’s advised level
of 0.4 ppm for mercury. The level for methyl mercury was tested at 10.33
times the ministry’s safe level of 0.3ppm. Another sample of dolphin
meat tested at 16 times the allowable level of mercury and 12 times the allowable level of methyl mercury. Some of the dolphin meat results were
higher than seafood tested during the Minamata catastrophe, according
to Dr. Shigeo Ekino of Kumamoto Science University in Kyushu. Dr. Ekino
is famous for his study of brain specimens from deceased Minamata victims
that reveal even low levels of methyl mercury can damage or destroy neurons.
In tests conducted over several years pieces of meat taken from pilot
whales slaughtered at Taiji all ran many times the government’s
upper limit of 0.4 ppm. One was found to have 11 ppm of mercury and 2.6
ppm of PCBs, in its flesh. The government’s limit on PCBs is 0.5
ppm.
Gyokyo, the leading supermarket in Taiji, stopped selling pilot whale
after it was shown to have dangerous levels of mercury. The town’s
other supermarket, owned by the fishing cooperative continues to sell
the toxic pilot whale meat. The local schools have refused to accept further
deliveries of dolphin meat and it appears villagers are eating less of
the traditional product.
Dr. Tetsuyo Endo, a researcher at the University of Hokkaido, has published
numerous studies showing dolphin meat sold to the public often exceeds
government health standards of 0.4 parts per million of mercury. The highest
level he has found is 100 ppm from a bottlenose dolphin. Endo has called
for a government investigation into the selling of dolphin meat. “Dolphins
are not food,” he said.
Dr. Endo has told BlueVoice.org the consumption of organ meat of some
dolphins could cause “acute mercury poisoning.” He advises
these products be taken off the shelves immediately.
High levels of mercury in marine products is by no means a problem restricted
to Japan. It is a worldwide phenomenon. But the problem is amplified many
times for consumers of dolphin meat.
Dr. Jane Hightower, an internist in San Francisco warns “some chemicals
act synergistically. Together, combinations such as mercury and lead, cadmium or aluminum can cause more risk than mercury alone”. (Consumers
of dolphin meat in Taiji show dangerously elevated levels of cadmium,
which is thought by some to be a carcinogen). She is also concerned about
levels of mercury in terms of heart health.
A mercury level in hair of 2ppm doubles the risk of heart attack and
triples the risk of death from heart attack.
The highest concentrations reported of cadmium in kidney and liver of
cetaceans have been 125 and 134 ug/wet g in pilot whales.
Mercury levels tested in hair of Japanese populations obtained from 10
districts indicated that 25% of Japanese females of child-bearing age
were estimated to be exposed to methyl mercury over the provisional tolerable weekly intake (ptwi) level set by the Japanese ministry of health and
welfare. Yasutake et al Journal of Health and Science.
Yasutake et al took hair samples from 8665 individuals from 1999 –
2002, collecting samples in barber shops and primary schools in 9 prefectures.
Information was gathered on age, sex, amount and species of fish eaten
and artificial waving and coloring of hair. Analysis revealed that mercury levels were significantly correlated with the intake of fish and shellfish.
The Japanese agencies regulating health have set a standard of 0.4 ppm
for mercury and 0.3ppm for methyl mercury – but these levels are
not even applied to whale and dolphin products. The United States EPA
defines safe levels for methyl mercury at 0.1 ppm.
The mayor of Taiji has said the local dolphin hunting industry has lost
US$1-million from adverse reaction to publication of information about mercury content in dolphin meat. Dolphin and whale meat is still sold
and dolphin and whale hunting continues to be subsidized by the government
at the expense of Japanese taxpayers. Japanese have vivid memories of
the Minamata tragedy in which more than 2,000 people were killed or sickened
from consuming fish contaminated with mercury.
Mercury is not the only toxin found in dolphin and whale meat.
Whale and dolphin meat can be highly contaminated by both heavy metals and PBOPs (persistent bioaccumulative organic pollutants) such as PCBs,
and pesticides such as DDT and chlordanes.
The Japan Fisheries Agency Food Sanitation Committee has advised pregnant
women not to eat bottlenose dolphin meat more than once every two months.
PERSISTANT ORGANIC POLLUTANTS – A LINK TO JAPAN’S
DECLINING BIRTH RATE?
Organochlorines such as PCBs, dioxins, PBDEs and many other persistent
organic pollutants are known to mimic estrogen and other hormones. They
are sometimes referred to as endocrine distuptors. Japanese who eat large
quantities of fish, and especially those who eat whales and dolphins,
may be exposed to very high levels of these endocrine disruptors. Men
may become more feminized and women accumulate higher than natural levels
of estrogen and estrogen imitators.
A group of Japanese scientists reported in September 2007 that the breast
milk of Japanese women tested was contaminated by PCBs. The scientists
reported the likely route of ingestion into human bodies was through consumption
of fish. “One of the causes of the human contamination is believed
to be intake of fish,” said Sochi Ota, associate professor at Setsunan
University. It should be emphasized that dolphins, at the apex of the
food chain, have far higher concentration of contaminants than most fish.
Sperm counts in Japanese men, already low, are decreasing and chemicals
that disrupt human hormones may be to blame, according to a report by
Yasunori Yoshimura, a professor of obstetrics and gynecology at Keio University.
An analysis of semen samples from 6,000 Japanese men found a 12 percent
decrease in the number of sperm over the past three decades. Samples taken
from medical students in the 1970s contained an average of about 65 million
sperm per millilitre of semen. The figures decreased to about 63 million
in the 1980s and further dropped to about 57 million in the 1990s. Environmental
chemicals that mimic human hormones could have a role in the decline in
sperm counts, Yoshimura said.
Japan has one of the highest life expectancies in the world. The ratio
of people aged 65 and over to the whole population more than doubled from
7.07% in 1970 to 18.0% in 2001. This ratio is magnified because of the
low recruitment rate of babies into the society.
Japan’s population is aging. A flat population level is only maintained
because Japanese are living longer. Recruitment into the population has
fallen to a record low. Japan’s population was 127.3 million as
of 2001. The annual growth rate fell below 1% in 1977 and by 1999 had
dropped to 0.16, a portion of this due to immigration not through birth
of Japanese.
The number of people under 15 years of age dropped to a post-war low
of 18.28 million in 2001, a decrease of 190,000 over one year.
Whether low sperm counts in Japanese men is related to this phenomenon
should be studied on an urgent basis.
Tests on pilot whale meat taken from Taiji found 2.6 ppm of PCBs. The
government’s limit on PCBs is 0.5 ppm. In humans, PCBs can cause
liver disease, ocular lesions, compromised immune response, reproductive
problems and cancer.
Dioxin, recognized widely as a carcinogen, is another toxin found in
dolphin and whale meat.
An expert in organochlorine (OC) contamination, Dr. K. Haraguchi, has
reported that one meal of 50 grams of whale or dolphin may constitute
the TDI (tolerable daily intake) of dioxin for a person weighing 50 kg.
A single gram of blubber from the most highly contaminated dolphin sampled
would exceed tolerable limits by a factor of three. In humans, OCs can
cause effects in reproductive/sexual development, plus immune system damage,
thyroid disorders, nervous system disorders, endometriosis and diabetes.
In a study presented to International Whaling Commission (IWC) conference
in Australia, Japanese researchers reported finding dioxin levels up to
172 times the tolerable daily intake in marketed whale meat. The study
was headed by Koichi Haraguchi of Daiichi University in Fukuoka, Japan.
Researchers looked at 38 types of whale and dolphin meat sold in 1999
and early 2000 in Japan.
Dolphin meat showed the highest levels of dioxins. Minke whales from
the north Pacific were next highest. Southern Hemisphere Minkes were relatively
low in this chemical.
Cetacean products such as bacon/blubber are contaminated to a degree
unacceptable for human consumption according to standards set by Japanese
health authorities for dioxin-like compounds. Haraguchi 2000.
Researchers concluded people who eat relatively large quantities of fish
are at risk for dioxin-induced neurobehavioral effects with particular
risk for infants. Simmonds, Haraguchi et al. Human Health Significance
of Organochlorine and Mercury contaminants in Japanese whale meat.
TOXICS IN WHALE MEAT
Japan obtains much of its whale meat from it’s widely rejected
pseudo-scientific hunts of whales in the Antarctic and Northwest Pacific.
While Japan calls these hunts “research” operations they have
been condemned worldwide. Drive fisheries, primarily conducted from the
village of Taiji, and harpoon hunts conducted on Dall’s porpoise
in the north of Japan are additional sources of cetacean meat.
The Asahi Shimbun (Japan’s second most widely circulated newspaper
) reported in 2003 that studies of several varieties of whale meat conducted
by the japan health ministry revealed that many samples contained unacceptable
levels of toxic chemicals, such as PCBs and methyl mercury. The samples
tested were taken from fat and muscle meat from five Beard’s beaked
whales taken off Northern Japan. The ministry’s research group detected PCB levels between 5 and 11 ppm and methyl mercury levels between 0.37
and 1.3 ppm in the whales muscles. The Health ministry limit is 0.5 for PCBs and 0.3 for methyl mercury in sea food.
The Provisional Tolerable Weekly Intake (PTWI) for methyl mercury would
be exceeded by an average consumption of only 16g of whale liver products
per week.
The highest level of mercury ever detected was 204 ppm in the liver meat
of a whale, exceeding the “safe” level by 400 times.
Japanese researchers report that approximately half the intake of dioxins in Japanese people comes from fish.
T-Hg (total mercury) levels found in boiled whale liver were high enough
to cause acute intoxication from a single serving. Contamination levels
of T-Hg and M-Hg in red meat from toothed whales were 8.94+/- 13.3 and
5.44 +/- 5.72 ug/wet g. These levels exceeded limits of T-Hg (0.4 ug wet
g) set by the Japanese Ministry of Health and Welfare by 22 and 18 times
respectively.
The ingestion of 500 mg of mercuric chloride can cause severe poisoning
and even death in humans. The consumption of boiled liver provides enough mercury to cause acute renal failure.
A recent study of dolphin and whale meat conducted by the Environmental
Investigation Agency (EIA) collected in Wakayama prefecture near Taiji
has shown elevated levels of PCBs in dolphin meat. Sample EIA 07-16 was
labeled Risso’s dolphin meat. But DNA testing showed it was either
one of the following: bottlenose, stenella or delphinus. The PCB level
was 1.512 pp. A sample of dolphin meat purchased in southwestern Japan
was in fact Risso’s dolphin and showed a level of PCBs at 1.243
ppm. The Japanese have set a level of .5ppm as a tolerable level for PCBs
in meat. So both samples of dolphin meat sampled by EIA were significantly
in excess this benchmark. In both cases levels of mercury and methyl mercury were over regulatory levels.
AMYLOIDOSIS IN WHALES NEAR JAPAN
Amyloidosis is a disease characterized by the tissue deposition of autologous
extracellular fibrillar proteins pressing adjacent tissues. There is only
one report of it in cetaceans. Among twelve Beaked Whales stranded along
the Sea of Japan, Amyloidosis was found in two of them. Livers were particularIy
swollen with marked atrophy of heaptocytes. Deposition of amyloid in kidneys,
heart, spleen, pancreas, adrenals was noted. Amyloidosis is associated
with diseases such as multiple myeloma. Tajima et al. Journal of Zoo and
Wildlife Medicine.
Study Shows Mercury Affects Brain Development
For immediate release: February 06, 2004
Harvard School of Public Health
Boston, MA— With methyl mercury a worldwide contaminant of seafood
and freshwater fish and known to produce adverse nervous system effects,
especially during brain development, researchers from the Harvard School
of Public Health and institutions in Japan, Denmark and the Faroe Islands
undertook an assessment of possible brain function impairment in adolescent
children due to prenatal exposure to mercury when the mothers’ diet
was high in seafood. The authors found that high levels of mercury passed
from mother to child in utero produced irreversible impairment to specific
brain functions in the children. The study was carried out in the Faroe
Islands and appears in the February issue of The Journal of Pediatrics.
Mercury exposures among the children in the study were assessed through
analyses of cord blood samples at birth and hair samples taken at ages
7 and 14. Some 1,022 mothers and their children from the Faroe Islands
participated in the research. The mothers’ hair mercury levels at
childbirth in most cases exceeded 1 microgram per gram, the exposure limit
recommended by the National Research Council and the U.S. Environmental
Protection Agency (EPA).
The Faroe Islands are located in the North Atlantic Ocean between Norway
and Iceland. The islands’ economy is centered on the fishing industry
and fish processing. The diet of the inhabitants includes high intake
of seafood and whale meat.
A second paper in The Journal of Pediatrics by the same authors reports
that the neurological changes are also linked to decreased nervous system
control of the heart function. At higher mercury exposures, the children
were less capable of maintaining the normal variability of the heart rate
necessary to secure proper oxygen supply to the body.
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CANCER IN DOLPHINS � AN EMERGING THREAT
Until recent years cancer was virtually unknown in dolphins. Today a
growing number of cancers are being found in dolphins around the world.
In cases where dolphins with cancer have been in a state of decomposition
that allowed analysis, high levels of POPs have been found, supporting
the hypothesis that organic contaminants are implicated in the etiology
of the disease. The susceptibility of dolphins to toxicants is made worse
because dolphins lack genes that process these chemicals (see technical
papers at back of this report). Because of genetic similarities with humans
it would be foolish to ignore this trend in dolphins.
Whole populations of dolphins are in danger of extinction due to accumulation
of toxic chemicals.
Human beings who eat fish from the environments shared with dolphins
afflicted with high levels of contamination would be well advised to take
these dangers into account in their selection and levels of consumption
of fish.
Only 33 cases of cancer have been found worldwide in cetaceans, other
than the SLE Beluga, according to Daniel Martineau. But this does not
mean that more cases than this do not exist. In most cases stranded dolphins
are found in a state of decomposition that disallows many forms of testing.
In addition budgets for such research are sparse.
St. Lawrence Estuary Belugas. The Beluga population
has dropped from an estimated 5,000 to current estimate of 500-600. The
SLE Belugas were protected from hunting by the Canadian government starting
in 1980 but so far there is no sign of recovery.
SLE Beluga are contaminated by polycyclic aromatic hydrocarbons (PAHs)
produced by local aluminum smelters. The extraordinary level of cancer
in this population is consistent with the hypothesis that PAHs are involved
in the etiology of cancer in mammals. Daniel Martineau, et al Cancers
found include epithelial cancer of the proximal intestine, gastric cancer,
gastrointestinal epithelial cancer and mammary cancer. Cancer of the proximal
intestine is rare among all species including humans. It is frequent in
bovine and ovine species exposed to herbicides such as 2,4-dichlorophenoxyacetic
acid. An interplay between a virus and environmental carcinogenic compounds
may be at work in the SLE Belugas. Particles consistent with papillomaviruses
have been observed in papillomas found in a significant number of carcasses.
Carcinogens are present in the environment of the SLE Belugas. Benzopyrene
was found in high concentrations in blue mussels in the Saguenay River.
Sediments of this river, part of Beluga habitat, contain 500 – 4500
ppb of total PAH dry weight, a concentration level significantly higher
than Osaka harbor where PAH concentrations are 2870 ppb. The PAHs originate
from upstream aluminum smelters. SLE Belugas feed in sediments. These
observations suggest that SLE Belugas ingest PAHs in benthic invertebrates
that may contribute to the elevated rate of digestive tract cancers in
the population. Martineau et al.
Martineau: Cancer in Wildlife. “The rate of cancer in the SLE Beluga
population is higher than in any other population of wild terrestrial
or aquatic animals”. Cancer was detected in 27% of adult beluga
whales found dead. The cancer rate of 163 per 100,000 animals is much
higher than in domestic animals and humans.
According to Martineau, “The human population living in this habitat
is affected by rates of cancer higher than found in other parts of Quebec
and Canada in general. Some of these cancers are epidemiologically related
to PAHs.”
In 50 Beluga examined in the Canadian Arctic no cancer was found.
The SLE Beluga are contaminated by heavy metals, PAHs, PCBs, DDT, and
their metabolites, which can, in some cases be more toxic than the original
chemical.
Cancer of the proximal intestine is rare in all animal species and humans
except in circumstances where the animal has been exposed to pesticides.
An interaction between viruses and environmental toxicants may be a factor
in the high cancer rates among SLE Beluga.
Almeria, Spain. An ovarian tumor was found in a juvenile
Cuvier’s Beaked Whale. High levels of PCB congeners were detected.
Residue levels of 13 PCB congeners and OC pesticides were also found.
Dioxin-like PCBs were greater than the threshold level for observed effects
on reproduction, carcinogenesis and immunity in mammals. Espinosa de los
Monteros.
Results of a study by Frenzilli showed a statistically significant increase
of DNA damage after PAHs exposure in three species investigated in the
Mediterranean - striped dolphin, bottlenose dolphin and a fin whale.
Florida
Six dolphins from three species were found by Greg Bossart along the East
Coast of Florida with immunoblastic lymphoma, also referred to as multiple myeloma. One hypothesis is that a retro virus was responsible for these
lymphomas. The dolphins were not tested for chemical contaminants but
were found in an area into which herbicides from the Lake Okeechobee sugar
industry flow.
In April, 2004 J. R. Jabera et al found a bottlenose dolphin stranded
alive off Gran Canaria (Canary Islands) with hepatosplinic lymphoma, AKA
immunoblastic lymphoma; AKA multiple myeloma. The researchers detected
eleven PCB congeners, 23 OC pesticides and 16 PAHs in this dolphin. High
concentrations of PCBs 153, 180, 138 and 187 found may have been associated
with the hepatosplinic lymphoma.
Texas Coast: Two cases of cancer were found among 90
bottlenose dolphins examined along the Texas Gulf Coast from 1991 –
1998. One was a myelogenous leukemia, the other a bile duct carcinoma.
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MULTIPLE MYELOMA IN DOLPHINS
Multiple myeloma is a cancer of plasma cells. Recent studies have shown
that chemical pollutants play a role in the etiology of this hematological
cancer in some cases.
Until recently cancer was virtually unknown in marine mammals. Today
it is a growing problem and indications are that chemical contamination
is a culprit.
BlueVoice is conducting a worldwide search for incidences of Multiple
Myeloma in dolphins and other marine mammals.
In 1997 Dr. Greg Bossart published a paper in which he described the
occurrence of Immunoblastic lymphoma (hereafter called multiple myeloma)
in five dolphins of three species found along the southeast coast of Florida
during a two year period. These were the first reported cases of multiple myeloma in dolphins. It was not possible to conduct tests for pollutants.
In April, 2004 J. R. Jabera et al reported in a paper entitled “Hepatosplenic
Large Cell Immunoblastic Lymphoma in a Bottlenose Dolphin with High Levels
of PCBs”, a case of multiple myeloma in a bottlenose dolphin found
in the Canary Islands. The dolphin was found stranded and alive. Eleven PCB congeners, 23 organochlorine pesticides and 16 PAHs were detected
in blubber and liver. Jabera concludes “High concentrations of PCBs
153, 180, 138, and 187 found in the liver may have been associated with
the hepatosplenic lymphoma (multiple myeloma).
In 2008 Michelle Fleetwood of the Armed Forces Institute of Pathology,
wrote of an adult female bottlenose dolphin found dead on a beach at Sullivan’s
Island, Charleston County, Southy Carolina. Her diagnosis was B-cell immunoblastic
lymphoma (multiple myeloma). She commented in her paper that hematopoietic
neoplasms are rare in cetaceans. Contaminant testing on this dolphin’s
tissues is pending as of June, 2008.
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POPS FACT SHEET
General Facts
- persistent organic pollutants (POPs) are organic compounds that resist
environmental breakdown via biological, chemical, and photolythic processes,
some taking as long as a century to degrade.
- POPs exposed to the environment are proven to travel long distances
from their origin via wind and ocean currents. Precipitation has been
found to carry PCBs (polychlorinated biphenyls)
- POPs therefore can be found globally, even in areas such as the Arctic
and Antarctica, far from their source. Human exposures in certain Arctic
areas are among the highest worldwide.
- POPs bio-concentrate as they move up through the marine food chain
and accumulate in the fatty tissues of living organisms at higher trophic
levels.
- Marine mammals around the world carry high burdens of POPs.
- Although many countries have banned these chemicals, they remain stockpiled,
are produced or used illegally, or, because of lengthy half-lives, they
continue to exist in soil, or other environmental media.
- The United Nations is currently considering the elimination or reduction
of twelve of some of the most damaging POPs through the formulation
of an international treaty. Nine of the POPs chemicals under consideration
are pesticides that have been extensively used in both developed and
developing countries.
General Health Effects
- POPs can disrupt the endocrine, reproductive, and immune systems.
The developing brain and nervous system may be most vulnerable.
- POPs are capable of causing behavioral problems, cancer, diabetes
and thyroid problems.
- According to a landmark longitudinal study, babies whose mothers ate
large amounts of highly contaminated fish (PCBs were measured) from
Lake Michigan had lower birth weights, smaller head circumferences and
shorter attention spans than babies whose mothers did not eat fish.
Followed over 11 years, the exposed children have continued to do poorly
in a range of skills and development tests, including deficits in general
intellectual functioning, short- and long-term memory, and attention
span.
- The health of marine mammals has deteriorated significantly over the
past two decades. Many of the newly emerging and resurgent diseases
are associated with immune system dysfunction and suggest a broad environmental
distress syndrome.
- Marine mammals present a metabolic imbalance, so they are considered
one of the most vulnerable organisms with respect to long-term toxicity
of man-made chemicals such as organochlorines. Cetaceans (whales and
dolphins) are known to have a poor ability to detoxify organic pollutants
because they lack isozymes that are required to detoxify DDT and PCBs.
“The Dirty Dozen”
These 12 POPs are often referred to as the “dirty dozen”:
Aldrin – an organochlorine insecticide;
- A pesticide used to control soil insects. It has been widely used
to protect crops such as corn and potatoes, to protect wooden structures
from termites.
- It is oxidized in the insect to form dieldrin, a neurotoxin.
- It is a carcinogen as well as a mutagen.
- It binds strongly to soil particles, is resistant to leaching into
ground water. It is released from soil by volatilization.
- Due to its persistent nature, aldrin is known to bio-concentrate.
- Aldrin is toxic to humans causing headache, dizziness, nausea, general
malaise, and vomiting, followed by muscle twitchings, myoclonic jerks,
and convulsions.
- Occupational exposure to aldrin, in conjunction with dieldrin and
endrin, has been associated with a significant increase in liver and
biliary cancer. -Aldrin may affect immune responses.
- Many countries, including the US have ended its usage and manufacture
- It is a carcinogen as well as a mutagen.
Chlordane – a manufactured pesticide;
- Chlordane is a broad spectrum contact insecticide that has been used
on agricultural crops as well as being used extensively in the control
of termites
Banned in US in 1988 by the EPA;
- Chlordane sticks strongly to soil particles at the surface and is
not likely to enter groundwater. As a result it can stay in the soil
for over 20 years and breaks down very slowly.
Bio-concentrates in fish, mammals, and birds;
- In both humans and animals, it can damage nervous and digestive systems,
and liver - Has caused convolutions and death;
- Recent human studies have linked chlordane exposure with prostate
and breast cancers.
DDT – a synthetic pesticide
- DDT is a toxicant;
- It has a half life of 2-15 years, and is immobile in most soils
- Breakdown products in the soil environment are DDE and DDD, which
are also highly persistent and have similar chemical and physical properties.
- Banned in the US for most uses in 1972.
- Subsequently banned for agricultural use worldwide, but is still
used to a limited extent in mosquito control in certain parts of the
world
- The use of DDT was found to be a major factor in the bald eagle and
the peregrine falcon population decline, as it caused the birds’
egg shells to thin.
- DDT and its metabolic products DDE and DDD magnify through the food
chain
- DDT bio-concentrates significantly in fish and other aquatic species,
leading to long-term exposure to high concentrations.
- At the chronic level, individuals who consumed contaminated fish
increased diabetes occurrences;
- The EPA, in 1987 , classified DDT as a probable human carcinogen.
- In 2007 a Canadian study found a positive association between DDE
and non-Hodgkins Lymphoma.
- Tests conducted by the CDC in 2002 showed that more than half of
subjects tested had detectable levels of DDT or metabolites in their
blood,
- The USDA tested cows milk samples in 2005 and found that 85% had
detectable levels of DDE.
Dieldrin – an insecticide;
- Closely related to aldrin which itself breaks down to form dieldrin
- it accumulates as it is passed along the food chain.
- Long-term exposure is toxic to many animals (humans included) far
greater than to the original insect targets.
- Currently banned in most of the world.
- Linked to Parkinson’s disease, breast cancer and immune, reproductive,
and nervous system damage.
- Endrin – an insecticide/rodenticide;
- Banned in many countries;
- It is likely to adsorb onto the sediments in surface water.
- An insecticide used on cotton, maize, and rice; a rodenticide used
to control mice and voles.
- It can bio-concentrate in the fatty tissues, of organisms living
in water. It is very toxic to aquatic organisms, namely fish, aquatic
invertebrates, and phytoplankton.
- Half-life in soil estimated at over a decade.
- endrin poisoning in humans primarily affects the nervous system.
Food contaminated with endrin has caused several clusters of poisonings
worldwide, especially affecting children.
Heptachlor – an insecticide;
- Similar to the insecticide chlordane
- The U.S. has banned the sale of heptachlor products in the United
States and virtually eliminated its use for any purpose
- Has a very stable structure, thus it can remain in environment for
decades;
- Possible human carcinogen.
Hexachlorobenzene (HCB) – a fungicide;
- A fungicide formerly used as a seed treatment, especially on wheat.
- Known animal carcinogen (liver, kidney, thyroid);
- Probable human carcinogen;
- After its introduction as a fungicide in 1945, for crop seeds, this
toxic chemical was found in all food types.
- Banned in the U.S in 1966;
- In humans it can cause liver disease, skin lesions, ulceration, hair
loss, thyroid damage;
- Human and animal studies have demonstrated that HCB crosses the placenta
to accumulate in fetal tissues and is transferred in breast milk.
- Extremely toxic to aquatic creatures. Risk of bioaccumulation in
an aquatic species is high
Mirex – an insecticide, flame retardant;
- Listed as a persistent, accumulative, and toxic pollutant by EPA in
the U.S.
- It was used to control fire ants and as a flame retardant in plastic,
rubber, paint, paper and electronics.
- Mirex is transported across the placenta and can be passed from mother
to child through breast milk;
- Most effected in animals is the liver;
- Proven to cause cancer in mice and rats and is a carcinogenic risk
to humans;
- Toxic for a range of aquatic organisms, with crustacea being particularly
sensitive.
- Mirex induces pervasive long-term physiological and biological disorders
in vertebrates.
- There is evidence of accumulation of mirex in aquatic and terrestrial
food chains to harmful levels
- Mirex is one of the most stable of the organochlorine insecticides
and is it is widespread in the environment.
- All uses of mirex as a pesticide were banned in the U.S. in 1978.
- mirex is still used in the USA mainly as a flame-retardant in plastics,
rubber, paint, paper and electronics.
- Effects on organisms combined with its persistence suggest that mirex
presents a long-term hazard for the environment
PCBs (polychlorinated biphenyls)
- Used as coolants/insulating fluids, also used in flexible PVC coatings
of electrical wiring and electronic components, pesticide extenders,
cutting oils, flame retardants, hydraulic fluids, sealants (used in
caulking, etc), adhesives, wood floor finishes, paints, and in carbonless
copy paper.
- PCBs are very stable compounds and do not degrade readily.
- Despite being banned in the 1970s due to their high toxicity, PCBs
still persist in the environment.
- Prior to the ban estimates have put the total global production of PCBs on the order of 1.5 million tons.
- PCBs have been detected globally in the atmosphere, from the most
urbanized areas that are the centers for PCB pollution, to regions north
of the Arctic Circle, carried by wind currents.
- Bio-concentrates in animals;
- PCBs can be transmitted to children via breast milk as well as through
the placenta.
- In humans, PCBs can cause liver disease, ocular lesions, lessened
immune response
- Babies born to women exposed to PCBs have been shown to weigh less,
have problems with motor skills, a decrease in short-term memory, and
compromised immune systems.
- PCBs alter estrogen levels in the body and contribute to reproduction
problems.
- Endocrine Disrupting Chemicals (EDC's) such as PCBs pose a serious
threat to reproduction in top-level predators.
- Biological magnification of PCBs has led to polar bears and whales
that have both male and female sex organs and males that cannot reproduce.
- Effects on animals are liver, stomach, thyroid damage, plus immune
system changes, changes in behavior, impaired reproduction.
- Some studies indicate that PCBs are associated with cancer in humans,
such as cancer of the liver and biliary tract. Recent research by the
National Toxicology Program has confirmed that PCB126 is a carcinogen.
- PCBs are known to induce Vitamin A deficiency in mammals, an affect
that may be associated with impairment of the immune system, reproduction
and growth.
PCDDs (Polychlorinated dibenzodioxins) – commonly
referred to as DIOXINS;
- dioxins are teratogens (cause birth defects), mutagens, potential human carcinogens;
- Known to accumulate in humans and wildlife due to dioxins’
ability to dissolve in fats and oils and their tendency to be water
insoluble. This means that even small amounts in contaminated water
can bio-concentrate up the food chain to dangerous levels.
- In humans, they can cause effects in reproductive/sexual development,
plus immune system damage, thyroid disorders, nervous system disorders,
endometriosis and diabetes.
- In animals and fish, studies have shown dioxin exposure to cause
cancer birth defects, liver damage, endocrine damage, and immune system
suppression.
- Studies have shown that exposure to dioxin increases the ratio of
female births to male births among a population.
- Concentrations of dioxins are found in all humans today, with higher
levels found in persons living in more industrialized countries.
- The estimated elimination half-life for dioxins in humans ranges
from 7.8 to 132 years.
- Dioxin enters the general population almost exclusively from ingestion
of food, specifically through the consumption of fish, meat, and dairy
products since dioxins are fat-soluble and readily climb the food chain
- Because Dioxins are lipophilic, breast fed children usually have
substantially higher dioxin body burdens than non-breast fed children
until they are about 8 to 10 years old.
- According to the EPA, 80% of Dioxin emissions are caused by coal
burning plants, municipal waste incinerators, metal smelting, diesel
trucks, land application of sewage sludge, burning treated wood and
trash burn barrels. Dioxins are also generated in bleaching fibers for
paper and textiles.
Polychlorinated dibenzofurans
- highly toxic;
- Properties and chemical structure similar to dioxins;
Toxaphene – an insecticide;
- highly toxic
- Banned in US in 1990, outlawed in 1991 by the Stockholm Convention
- Exposure can cause damage to lungs, nervous system, kidneys and can
be fatal
Additional POPs
PBDEs – (Polybrominated diphenyl ethers) flame
retardants
- PBDEs are used in plastic, foam and textiles in clothing, computers,
televisions, furniture and cars.
- PBDEs have been found at high levels in indoor dust
- Research has linked some chemicals in the flame retardants to effects
on thyroid function on brain function, reduced male fertility and damaged
ovarian development and the development of the embryonic nervous system,
impacting motor skills and behavior.
- These chemicals were banned in Europe in 2004/2005. In August 2003,
California became the first state to ban two forms of the fire retardants
chemicals known to accumulate in the blood of mothers and nursing babies.
In April 2007 Washington banned the use of PBDEs and in May 2007, the
state of Maine passed a bill phasing out the use of DecaBDE.
- levels of concentration in humans and marine mammals continue to
increase, particularly in the United States.
- Studies have found that PBDEs accumulate in human blood, fat tissue
and breast milk. It has been found that a woman can pass these chemicals
to her unborn child through the placenta.
- In the United States levels in human breast milk are 40 times higher
than in Europe and are steadily rising.
- Marine mammals like bottlenose dolphins, harbor porpoises, pilot
and beluga whales have been found to be contaminated with PBDEs. Birds
including cormorants and glaucous gulls, and popular food fish including
salmon and tuna have also been found to carry high concentrations of PBDEs
PFCs – perflorinated compounds;
- PFCs are used as industrial and commercial surfactants - wetting
agents that lower the surface tension of liquid.
- In contrast to the majority of organic pollutants that are deposited
in fatty tissue, perflorinated contaminants circulate in the blood and
accumulate primarily in the liver.
- PFCs are synthetic molecules that are thought to bioaccumulate and
are believed to be extremely resistant to physical degradation, biodegradation,
and biotransformation.
- Science has begun to demonstrate clear links between chemicals such
as phthalates, bisphenol A, and perflorinated compounds found in consumer
products including baby bottles, toys, and cosmetics to reproductive
disorders.
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MERCURY FACT SHEET
General
- It is a powerful neurotoxin
- Can cause major brain damage in developing fetuses, and mild tremors
and emotional disorder in adults who are exposed.
- Is responsible for many historical poisoning instances.
- Currently, seafood is the main source of exposure since mercury builds
up in aquatic animals and can reach considerable levels at peaks of
both salt and fresh water food chains.
- Normally seen as a thick, silvery-white liquid.
- It is the only metal in liquid form at room temperature.
- Methyl mercury is quickly ingested by fish, concentrating in aquatic
food chains, achieving significant levels in top predatory animals via bio-magnification.
- According to Harte et al., “Methyl mercury is also rapidly absorbed
by people who eat fish and can readily pass through the placenta of
pregnant women, exposing developing fetuses, and through the blood-brain
barrier into the brain.”
Exposure
- Mercury exposure is dependent upon its form; mercury vapor and methyl mercury are the most probable forms, as they are almost totally absorbed into the body.
- Methyl mercury exposure:
- Fish/fish products – 94%
- Inhaling mercury vapor – 6%
- Individuals consuming large amounts of fish get above-average exposure.
- According to the EPA, individuals consuming over 30 pounds of fish
yearly are at high risk.
- Some example species of concern:
- Freshwater – pike, trout, bass
- Marine – tuna, shrimp, snapper, halibut
Distribution
- Mercury has a tendency to be found near manufacturers using it, and
also close to mines, smelters, municipal solid waste incinerators, and
fossil-fueled power plants (Mercury is a contaminant in ores and fuels).
- Mercury is utilized in:
- Making electrical materials, including batteries, smoke detectors,
mercury lamps/switches – 56%
- Producing chlorine/caustic soda – 12%
- Anti-mildew agent found in paints – 10%
- Industrial/control instruments – 6%
- Other – 16%
Health Effects
Methyl mercury (commonly found in fish) has major effects related to the
nervous system (especially in developing fetuses and small children).
- Mildest exposures – malaise, blurred vision, pins-and-needles
tingling.
- More severe exposures – vision loss, lessened hearing, speech
disorders, shaky movements/unsteady gaits.
- Most severe exposures – mental derangement and coma (most common
result is death).
Prenatal/early childhood are the most vulnerable times to methyl mercury poisoning, as this is a time of fast brain development.
- Methyl mercury exposure to pregnant women (mild) – later accomplishment
of baby’s developmental stages, minor neurological abnormalities
in baby.
- More severe – major developmental effects, including unusual
location of brain structures, impairment of motor/mental development
– severe cerebral palsy, spasticity, incontinence, blindness,
poor language development); effects cannot be reversed.
Example of methyl mercury contamination – Minamata Bay, Japan:
industrial chemicals infected fish, exposing many people to large amounts
of mercury.
Mercury vapor
- Mildest exposures – loss of memory, tremors, anxiety/irritability,
insomnia, appetite loss, introversion.
- Moderate – major mental disorders/motor disturbances, damage
to kidney.
- High-level – Lung damage, death.
- Evidence shows high abortion rates in pregnant women exposed to mercury
vapor.
Inorganic mercury compounds
- Not very toxic, as they are not well absorbed.
- Large consumption (several grams) – death by kidney failure,
nerve damage.
Prevention
- Individuals who consume fish and other seafood should reduce/eliminate
consumption of contaminated fish species.
Environmental Effects
- Industrial inorganic mercury discharges are converted by bacteria
in fresh and sea water (as well as in sediments) into organic methyl mercury.
- Via bio-magnification, low-food-chain fish quickly accumulate methyl mercury, and higher-level aquatic organisms are therefore exposed.
- Fish such as swordfish, pike and trout contain greater methyl mercury concentrations than the waters of their origin.
- Another environmental process involves acid rain; acid can cause the
organic mercury to convert to forms quickly taken in by aquatic organisms, thus exposing more humans to methyl mercury.
- Mercury is toxic to fish and other marine and freshwater life forms.
Regulatory Status
- Mercury content in water is regulated by the EPA;
- Food – FDA
- Workplace air – OSHA
Mercury is noted as a “hazardous air pollutant” by the Clean
Air Act of 1990.
Additionally, it is on the EPA “community right-to-know”
list.
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THE INABILITY OF DOLPHINS TO METABOLIZE CERTAIN PCBS
As we learn of the increasing levels of organochlorine and heavy metal
pollution in fish and mammals in the sea we are simultaneously finding
dolphins have a lesser capacity than birds and terrestrial mammals to
process these toxicants. The convergence of these factors pose catastrophic
risk to dolphin populations worldwide.
In a paper entitled CAPACITY AND MODE OF PCB METABOLISM IN SMALL CETACEANS
five Japanese scientists (Shinsuke Tanabe et al) determined that all species
of small cetaceans can metabolize some of the lower chlorinated biphenyls.
They further determined that the metabolic capacity to process certain PCBs of small cetaceans was extremely low as compared to those of birds
and terrestrial mammals. They found that small cetaceans have no capacity
to metabolize a group of PCBs with adjacent non-chlorinated meta and para
carbons in biphenyl rings.
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CYP1A1 - A TELLTALE GENE
CYP1A1 – Because CYP1A1 is activated by exposure to POPs it is
considered a bio-marker for those chemicals. It is also a possible trigger
for cancer.
Although dolphins share most human mammalian genes, including CYP1A and
CYP2B, they lack the ability to adequately catabolize type I and II dioxins,
which therefore preferentially accumulate. Observed results of these bioaccumulations
are suppressed immunity, infections, and cancers, including B-cell lymphomas
and “myeloma-like” immunoblastic lymphomas. (Bossart) Studies
are now underway to correlate recent bioaccumulation of POPs in dolphins
and humans, genetic predispositions and myeloma onset. Probability calculations
for risk of developing myeloma will support interventions to reduce both
contamination of the marine environment and elimination of toxic exposures.
Durie and Jones.
CYP1A1 is a gene that encodes a member of the cytochrome P450 superfamily of enzymes. It is primarily involved in xenobiotic and drug metabolism.
It is inhibited by fluoroquinolones and macrolides; induced by aromatic
hydrocarbons. There are 3 main subtypes of CYP1A: M1, M2 and M3.
CYP1A1 and CYP1B1 are regulated by the Aryl hydrocarbon receptor, a ligand
activated transcription factor. They are part of the Phase I reactions
in drug metabolism.
CYP1A1 in deep blubber was significantly higher in dolphins from Charleston
Harbor, SC than from the Indian River Lagoon in Florida. It was highest
in pregnant-lactating dolphins. In all dolphins CYP1A1 in the deep blubber
layer was positively related to concentrations of OH-PCBs in plasma. The
OH-PCBs have the potential to interfere with thyroid hormone function.
Monte et al
Cetaceans have high levels of CYP1A and low levels of CYP2B. St. Lawrence
Estuary belugas have elevated levels of both enzymes, probably because
CYP are induced by high levels of PCBs.” Elevated CYP1A levels may
trigger intestinal cancer by activating ingested PAHs into carcinogenic
compounds.” Martineau. Environmental Health Perspectives 3/2002
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THE STRIKING SIMILARITY BETWEEN HUMAN AND DOLPHIN GENOMES
Humans and dolphins may be genetically more similar than anyone had previously
imagined.
Scientists working at Texas A & M have found that the dolphin genome
and the human genome as “basically the same.” Dr. David Busbee
and his team including Mark Evans compared human chromosomes with those
of dolphins and concluded that dolphins hold many of the same chromosomes
as humans.
This similarity may help accelerate the mapping of dolphin genes.
“We started looking at these and it became very obvious to us that
every human chromosome had a corollary chromosome in the dolphins,”
said Busbee.
DNA is wound into a spool that constitutes a chromosome. Genes are organized
along the chromosome. Two complimentary strands of DNA are wound together
to produce the chromosome. Each chromosome carries different genes. Dolphins
have 44 chromosomes and humans have 46.
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THE INTERNATIONAL MYELOMA FOUNDATION IDENTIFIES POTENTIAL LINK BETWEEN
GENETIC PATHWAYS AND ENVIRONMENTAL RISKS FOR MYELOMA
North Hollywood, CA, and Atlanta, GA,
December 11,2007
The International Myeloma Foundation (IMF) http://www.myeloma.org today
said findings from its myeloma DNA bank identified genetic links to bone
disease in multiple myeloma, a cancer of cells in the bone marrow, that
in some cases can also include bone deterioration. These findings also
may both support and explain associations that have been observed between
environmental toxins such as dioxins and benzene, and an increased risk
for myeloma. The findings were made with resources from Bank On A Cure®
(BOAC), the world's first repository of DNA samples created to advance
the understanding of myeloma. They were presented at the 49th Annual Meeting
of The American Society of Hematology in Atlanta on December 11th.
The study found that genetic pathways associated with the ability to
neutralize environmental toxins are defective in patients with classic
myeloma (myeloma with bone involvement). These pathways are identified
as specific segments of genes called single nucleotide polymorphisms or
SNPs that are known to be associated with toxin metabolism and DNA repair.
These findings are in line with observations of patient populations and
groups of workers including firefighters that had previously demonstrated
a correlation between increased risk for myeloma and exposure to hydrocarbons
and related chemicals.
"Identifying these genetic pathways was unexpected," said Brian
G.M. Durie. M.D., chairman of the International Myeloma Foundation and
lead author of the BOAC presentation. "We were looking at bone biology
and the SNPs associated with toxin metabolism fell into place. Now, working
back through the gene pathways, we have a robust model of myeloma bone
disease that may explain the epidemiological observations."
*Abstract #816: "Genetic Polymorphisms Identify the Likelihood
of Bone Disease in Myeloma: Correlations with Myeloma Cell DKK1 Expression
and High Risk Gene Signatures" Brian G. M. Durie, MD, Chairman, International
Myeloma Foundation
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NEW BIOACCUMULATIONS OF TOXINS IN RESIDENT COASTAL DOLPHINS SIGNAL DANGERS
OF HUMAN MYELOMA
Brian GM Durie1 and Hardy Jones2
1Hematology/ Oncology, Cedars-Sinai Comprehensive Cancer Center, Los
Angeles, CA, USA; 2Bluevoice, St. Augustine, FL, USA
Dolphins and humans are exposed to the same toxins in seafood. Over 2
billion people worldwide rely on seafood as their major source of protein
and 60% of people live in coastal areas. Resident coastal dolphins are
exposed to marine pollution in the same fashion as humans who frequently
consume seafood, thus any indication of disease in dolphins has implications
both for humans who eat regularly from the same areas and/or are otherwise
exposed to the same toxins.
Although ecotoxicologic studies of marine environments are very complex,
(Irwin: Aquatic Mammals 31: 195-225, 2005), the bottlenose dolphin is
a sentinel species for biomonitoring purposes. Tissue levels of many known
carcinogens such as DDT, DDE, dioxins (e.g. PCDDs and 2,3,7,8 TCDD), BaP, PAHs, and more recently PFC and PBDEs (water repellants and fire retardants),
reflect bioaccumulation in both dolphins and humans. Target sites where
human and dolphin disease have been contrasted and compared are: North
America (Alaska; Puget Sound; San Francisco Bay; Gulf Coast and Florida;
St. Lawrence Seaway); Japan (Osaka Bay); Sweden; Coastal UK and Hong Kong
(Pearl River estuary). For Alaska, Florida, Japan, Sweden and coastal
UK, there are highly significant correlations between fish contamination/
consumption and excess risk of human myeloma. Inuit people who eat contaminated
fish, have high organochloride (dioxins) levels in blood and tissues and
an increased risk of myeloma. Likewise for Swedish fisherman comparing
Baltic (more contamination) versus west coast levels of dioxins and myeloma.
In Japan, a case control study provides a highly significant odds ratio
of 5.89 for agriculture/ fisheries as occupational factors. A separate
study gives an annual age adjusted incidence of 7.03/100,000 for the Osaka
Bay fishing region. Around Lake Okeechobee Florida an incidence rate of
6.52/100,000 correlates with both contamination and commercial fishing
licenses.
Although dolphins share most human mammalian genes, including CYP1A and
CYP2B, they lack the ability to adequately catabolize type I and II dioxins,
which therefore preferentially accumulate. Unfortunately, observed results
of these bioaccumulations are suppressed immunity, infections and cancers
particularly B-cell lymphomas and “myeloma-like” immunoblastic
lymphomas (Bossart: J. Vet Diagn Invest 9: 454-458, 1997). This pattern
of diseases in turn corresponds with the local and systemic effects exemplified
in Balb/c mice during pristane-induced plasmacytogenesis and in humans
exposed to toxins.
Newly recognized persistent organic pollutants such as water repellants
(PFCs) and flame-retardants (PBDEs) are a particular concern, both because
of rapid recent bioaccumulation in dolphins with associated disease manifestations
plus the potential for wide global dispersal and diverse routes of human
exposure. Numerous consumer goods contain PBDEs, including electronics,
carpets, furniture and textiles. Genetic studies help refine probability
calculations to assess risk using the union rule for independent events.
Studies are now underway to correlate recent bioaccumulations in dolphins
and humans, genetic predisposition and myeloma onset. Probability calculations
for risk of developing myeloma will support interventions to reduce both
contamination of the marine environment and elimination of human toxin
exposures.
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MULTIPLE MYELOMA, CLUSTERS, CLUES AND DIOXIN
Please download PDF file Here
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