Rising ocean surface temperatures due to climate change could make fish accumulate more mercury inside their bodies, putting people who eat seafood at increased health risk, scientists have found.
Till now, little has been known about how global warming may affect mercury bioaccumulation in marine life, and no previous study has demonstrated the effects using fish in both laboratory and field experiments. Mercury released into the air through industrial pollution can accumulate in streams and oceans and is turned into methylmercury in the water.
Researchers at Dartmouth College in the US studied killifish under varying temperatures in the laboratory and in salt marsh pools in the state of Maine. Fish in the marshes ate insects, worms and other natural food sources, while the lab fish were fed mercury-enriched food. Results showed the fish in warmer waters ate more but grew less and had higher methylmercury levels in their tissues, suggesting increase in their metabolic rate caused the increased uptake of mercury. The study was published in the journal PLOS ONE.
