Some low-dose chemical pollutants in farmed food, and these are in farmed salmon, have just been shown to have worse health problems for humans than the same chemicals in higher doses.
Dozens of hormone-disrupting chemicals include small amounts of BPA (bisphenol A), PCBs, dioxins and atrazine, a pesticide. Atrizine is used for on-land farm crops and thus the use of soybean, corn and other plant oils to replace fish meal oil, that contains PCBs, dioxins and so on, doesn't represent a clear healthy alternative to the forage fish that have been fished down for use for fish feed (and still is in Peru). The point is that wild Pacific salmon have lower levels of these chemicals than farmed salmon.
Read this: http://edrv.endojournals.org/content/early/2012/03/14/er.2011-1050.full.pdf+html.
Go back to this article on fishfarmnews to read the list of chemical pollutants in farmed salmon: http://fishfarmnews.blogspot.ca/2011/11/key-documents-levels-of-pcbs-pops-and.html.
The 2012 article reviews hundreds of scientific studies and is a brilliant synthesis of world wide science on the effects of hormone-mimicking chemicals found in our foods. Here is the abstract:
For decades, studies of endocrine-disrupting chemicals (EDCs) have challenged traditional concepts in toxicology, in particular the dogma of “the dose makes the poison,” because EDCs can have effects at low doses that are not predicted by effects at higher doses. Here, we review two major concepts in EDC studies: low dose and nonmonotonicity. Low-dose effects were defined by the National Toxicology Program as those that occur in the range of human exposures or effects observed at doses below those used for traditional toxicological studies. We review the mechanistic data for low-dose effectsanduse a weight-of-evidence approach to analyze five examples from the EDC literature. Additionally, we explore nonmonotonic dose-response curves, defined as a nonlinear relationship between dose and effect where the slope of the curve changes sign somewhere within the range of doses examined. Weprovide a detailed discussion of the mechanisms responsible for generating these phenomena, plus hundreds of examples from the cell culture, animal,andepidemiology literature.We illustrate that nonmonotonic responses and low-dose effects are remarkably common in studies of natural hormones and EDCs. Whether low doses of EDCs influence certain human disorders is no longer conjecture, because epidemiological studies show that environmental exposures to EDCs are associated with human diseases and disabilities. We conclude that when non-monotonic dose-response curves occur, the effects of low doses cannot be predicted by the effects observed at high doses. Thus, fundamental changes in chemical testing and safety determination are needed to protect human health. (Endocrine Reviews 33: 0000–0000, 2012.
This is scary and farmed salmon are scarier than wild Pacific salmon.