The dynamics of mercury toxins in the oceans' food web

Methylmercury, a toxic form of mercury that is readily absorbed from the gastro-intestinal tract and can cause in a variety of health issues, poses a significant threat to marine animals at the top of the food web.

A new study confirms that Artic species of these animals have higher concentrations of methylmercury in their tissues compared with animals lower in the food web; however, it also shows similar trends in selenium, which could help play a protective role against the toxic effects of mercury.

"Methylmercury concentrations increased through the food web at greater rates than observed in several earlier studies, especially at lower latitudes," said lead author Dr. Anders Ruus, author of the Environmental Toxicology & Chemistry study.

"This corroborates earlier suggestions that biomagnification may be higher in Arctic systems and adds to our knowledge of methylmercury dynamics in the Arctic."