The Japanese scientists bought samples from across the country, and found that every single slice of toothed whale red meat Japan's most popular whale product exceeded that country's provisional limit on mercury, with some samples containing almost 200 times the maximum value. The researchers also found that mercury levels were higher in whales caught off the coast of the southern part of the country.
The findings are scheduled to appear in the June 15 edition of Environmental Science & Technology, a peer-reviewed journal of the American Chemical Society, the world's largest scientific society.
"About 17,000 toothed whales are caught annually off the Japanese coast," says Tetsuya Endo, Ph.D., a professor at the Health Sciences University of Hokkaido, Japan, and lead author of the paper. "Despite extreme contamination with mercury, toothed whale products have been sold for human consumption without any regulation."
"These particular meat samples were from packaged food products that someone would have eaten, if they had not been purchased for pollutant analysis," says Frank Cipriano, Ph.D., director of the Conservation Genetics Laboratory at San Francisco State University. "This is a clear signal that Japan has a major health problem that the government has not addressed."
The levels of mercury measured by the scientists are similar to or higher than the levels in fish eaten by people in the Minamata Bay area of Japan, Endo says. The region is well known for its previous problems with mercury. In the 1950s and early 1960s, hundreds of children were born with birth defects caused by their mothers' repeated consumption of contaminated fish.