Unsavory salmon? Report reveals how chemicals swim up food chain
Aug. 10, 2018—Whether you bake it, grill it or poach it, salmon is a super-delicious dish—not to mention loaded with protein, omega-3 fatty acids and vitamin D.
But here's some food for thought about the food going into some salmon: A study in the journal Environmental Science & Technology found that farmed salmon can be contaminated by the feed they are provided.
For the study, researchers looked for the presence of polybrominated diphenyl ethers (PBDEs) in the environment.
In the past, PBDEs were often added to electronics and other consumer goods to make them fire-resistant. But in 2004, many nations banned PBDEs to protect people and the environment. In humans and in animals, PBDEs can act as endocrine disruptors. Such chemicals may interfere with the body's hormone-making endocrine system. They're linked to developmental problems in children.
PBDEs are still around though. One reason is they last a long time. PBDEs also continue to enter the environment. For instance, that may happen in countries where electronic waste recycling is loosely regulated.
The link to fish food
Researchers found that farm-raised salmon fillets were much more likely to be contaminated with PBDEs if their feed came from places with little or no environmental regulation. That was true even when fish were kept in clean, well-regulated waters. In fact, the fish's food source was a bigger predictor of pollutants than the farm's location.
Remember, this study doesn't say that farm-raised fish contain harmful levels of chemicals. Nor does it say that you should not eat salmon from farms or that they aren't as safe as wild salmon, which can also have contaminants. But it does suggest that potentially harmful chemicals are more likely to wind up in salmon—and possibly other fish—via the food chain. Knowing that is increasingly important in today's global market, in which farms are more likely to import their fish feed from around the world, the researchers noted.