Dolphins Are Not Food
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 an examination of 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, in a hideously ironic way, 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 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. 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 and headaches. 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 the largest of the dolphin family. 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 134 and 125 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.
Persistent 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 disruptors. 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 is 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 and cancer.
Dioxin, recognized widely as a carcinogen, is another toxin found in dolphin and whale meat. An expert in organochlorine 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, they 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. Tajima et al. Journal of Zoo and Wildlife Medicine.
For immediate release: February 06, 2004
Harvard School of Public Health
Boston, MA— With methylmercury 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.
View the Bluevoice Publication "Dolphins Are Not Food" in Japanese.