Salmon may be the most popular fish in the U.S. It's beloved in part because it provides a lot of omega 3 fatty acids, which are good for the brain and the heart.
Unfortunately, not all salmon is caught the same. A recent study published in SCIENCE revealed that farmed salmon contains way too much cancer-causing chemicals such as polychlorinated biphenyls (PCBs), dioxins, and two notorious pesticides. These pollutants are so much that the authors suggested people should not eat more than three servings in a whole year. This study was done on thousands of salmon samples from many countries including U.S. canada, and european countries. This contamination is believed to be caused by the salmon feed which got polluted. On the contrary, wild salmon contains much less of these pollutants.