In their study, the researchers artificially increased the levels of mercury in a lake ecosystem in western Ontario by adding an inorganic and less toxic form of mercury. They spent the ensuing 7 years monitoring the levels of mercury in the food chain, focusing in particular on the lake's top predator, the northern pike. They discovered that the majority of the mercury absorbed by the northern pike population came from the amounts they added to the lake; this led them to conclude that eliminating the mercury from power plant emissions - the primary source of the metal entering the lake ecosystem - would greatly contribute to the aquatic life's rapid decontamination.John Rudd, a biogeochemist and co-author of the study, said the next part of the experiment will consist of halting the addition of mercury to the lake and monitoring the metal's concentrations in the lake's organisms. In addition to demonstrating the speed with which mercury levels can build up within the bodies of fish, James Wiener - an aquatic toxicologist at the University of Wisconsin, La Crosse - stresses the study's significance in showing "the probable effectiveness of reducing emissions." No arguments there.
UPDATE: As JL notes in the comments, the significance of this study shouldn't be hastily extrapolated to other bodies of water; the particular lake ecosystem's features may have been in large part responsible for the results (time will tell). Also, the results certainly shouldn't imply that big businesses and industry interests go ahead and upp their mercury use by arguing that decontamination occurs rapidly.
Reducing emissions is key; the study's larger implications should be viewed in the context of future research on the subject.
Via ::ScienceNOW: Fish Quick to Recover From Mercury (news website)
See also: ::One in Every Four New Yorkers Has Elevated Blood Mercury Levels, ::Got Mercury? Here is a Calculator to Figure it Out
Image courtesy of redjar via flickr