Mercury Takes Algae Road to Ocean Fish
Ocean fish can contain high levels of mercury, even though mercury levels in the seawater around them are extraordinarily low. Now, scientists have an explanation for what’s going on.
A new study in the Pacific Ocean suggests that algae at the water’s surface absorb mercury from the atmosphere and then sink to mid-depths, where they decompose and release methylmercury, a highly toxic form of the metal that poisons both fish and the people who eat them.
Mercury concentrations have increased in the Pacific by 30 percent in the last 20 years, the study found. And if emissions continue to rise as expected, the scientists predict another 50 percent jump by 2050.