- Ivan Walsh via Flickr
- Farm-raised fish can still absorb mercury, since most fish farms are located in the ocean, close to or abutting the shoreline. They can also absorb PCBs and dioxins, as the near-shore waters they occupy are the first stop for run-off from land-based sources of pollution. Pictured: A fish farm in Shanghai.
Courtesy of: EarthTalk®
E — The Environmental Magazine
Dear EarthTalk: I thought “farm raised” was the way to go when buying fish, to avoid mercury contamination. But are there other concerns about farm raised that make some fish a poor choice for good health? What are the safest fish to buy and which should be avoided? And what about those frozen blocks of fish I get at Trader Joe’s? Are they safe to eat? — Tim Jeffries, Springfield, MA
Mercury is a neurotoxin that settles into the ocean in large concentrations after we spew it out of industrial smokestacks when burning fossil fuels like coal and oil. It is then taken up by smaller sea life such as plankton and then spread up through the food chain as larger fish eat smaller ones. We humans then eat the mercury-laced seafood—wild salmon, tuna, swordfish and other fish—and breathe it in our air. Repeated exposure to mercury pollution can cause brain, kidney and developmental problems for people.
This article appears in Jun 16-22, 2011.