Topic summary contributed by volunteer(s): Linda
Biomagnification refers to the concentration of toxins in an organism as a result of its ingesting other plants or animals in which the toxins are more widely disbursed. Biomagnification is one way humans are exposed to dangerous pollutants and other toxins: contaminants may accumulate in the fat of animals, and humans are exposed to the contaminants when they eat the animal products. The highest levels of toxins are found in fatty fish like salmon, with farmed Atlantic salmon appearing to be the single largest source. Consuming a plant-based diet and decreasing or eliminating meat, dairy, and fish intake may significantly reduce exposure.
Biomagnification and the Food Chain
One example of biomagnification relates to the BMAA neurotoxin, which may contribute to ALS, Alzheimer’s, and Parkinson’s. BMAA is produced by blue-green algae in many rivers, lakes, and oceans, ends up in seafood, and is passed along to humans who eat the seafood. Another example is endocrine-disrupting industrial pollutants such as alkylphenols, which may increase cancer cell growth. Pollutants can come down in the rain and then accumulate up the food chain. Even small molecules from medications like Benadryl, Cardizem, Tegretol, Lopid, Zoloft, and Prozac—excreted in urine and ending up in rivers and streams—are found in fish consumed by humans. Toxins like arsenic, lead, mercury, dioxins, PCBs, and even DDT (banned decades ago) have bioaccumulated in seafood, poultry, dairy, eggs, and other animal products and pose threats to human health.
Cooking does not destroy the toxins or drugs that have bioaccumulated in food.
The USDA, FDA, and EPA are supposed to test for these contaminants, but the Inspector General found that the national residue program is not accomplishing its mission of monitoring the food supply for harmful residues.