A groundbreaking environmental study to be published in a prestigious American science journal proves that mercury atmospheric emissions will end up in fish in as little as three years. Biologists from the University of Alberta in Edmonton, Canada, played a key role in designing and carrying out the experiment.
The study concludes that if mercury emissions from coal-fired power plants and other industrial activities were to be cut immediately, the amount showing up in fish would begin to go down within a decade.
It will appear in the Proceedings of the National Academy of Sciences of the United States of America online edition next week.
This breakthrough study (called METAALICUS - Mercury Experiment to Assess Atmospheric Loading in Canada and the United States) involved government agencies and universities on both sides of the border. It has global implications.
"Before this study, no one had directly linked atmospheric deposition (mercury emissions) and mercury in fish," says study co-author Vincent St. Louis of the University of Alberta.
The experiment filled a major gap in scientists' understanding of how mercury moves from the atmosphere through forests, soils, lakes and into the fish that people eat.
Its immediate value is that it provides undeniable proof of a direct link, said St. Louis, who specializes in what is called whole-ecosystem experimentation.
He said it should spur policy-makers to enact regulations for more rapid reductions in mercury emissions by industry.
"We can say conclusively that if you reduce mercury emissions it will result in less mercury in fish."