http://www.onearth.org/earthwire/tuna-mercury-levels-rising?utm_source=tw&utm;_medium=tweet&utm;_campaign=socialmedia

A study published yesterday in the journal Environmental Toxicology and Chemistry suggests that day has come. Mercury levels in fish are indeed rising, and it’s probably going to get worse.

Over the past 17 years, the researchers conclude, the concentration of mercury in yellowfin tuna has increased by approximately 3.8 percent annually. At the current rate of mercury emission, they could become a very dangerous thing to eat in a decade or two.
A scary and troubling trend.

There is a link to the actual scientific journal entry in the article I linked but the writer did a good job of distilling it down and providing some good background information on the subject.
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