One Awesome Blender

Monday, April 7, 2014

Just say “no” to farmed salmon


Twenty years ago, a lead article in the New England Journal of Medicine reported that men in a Danish fishing village who ate at least 30 oz of salmon a week had half the risk of getting a heart attack as their bovine-consuming neighbors.

Since heart disease had been, until very recently, the leading cause of death in this country physicians have been recommending that everyone eat fish at least once weekly. In addition to its benefit in reduction of cardiovascular mortality, fish oils have also been found to be of benefit in reducing arthritis and other inflammatory disorders and to improve cognition (particularly in the offspring of fish consuming moms). The NEJM article was published in May of 1985 and between 1987 and 1999 the annual salmon consumption in the United States increased by 23%. During the same time period it increased by 14% in Europe.

This increase in fish consumption has unfortunately not proven to be a boon to the hardy fishermen and women of Alaska. In fact, since the Exxon Valdez disaster these hard-working folks are getting far less per pound for their fish than they were prior to the disaster (which is still not cleaned up). Close to 60% of the salmon now sold is raised in farms located around the globe (British Columbia, Washington State, Chile and Northern Europe) in which Atlantic salmon (genus Salmo) are crowded into pens and fed fish meal pellets. If you are looking at salmon in the grocery store or the restaurant and it says just “salmon” or “Atlantic Salmon”, it is farmed. The presence of these pens in the Pacific Northwest pose a serious threat to the native runs of pacific salmon (genus Oncorhyncus) in those areas.

While the potential health benefits of wild salmon are well known, the potential toxicity of the farmed salmon needs to be highlighted. Several studies have now been done measuring the levels of polychlorinated biphenyls, dioxins, and other persistent chlorinated contaminants in farmed salmon. A study done by the Food Safety Authority of Ireland found that farmed salmon had an average of four times the amount of PCBs and Dioxins as wild salmon. In the United States, the Environmental Working Group (ewg.org) did a small study of farmed salmon that were purchased at stores in Washington DC, San Francisco, and Portland, OR. They found that seven of the ten farmed salmon purchased had levels of PCB that should raise health concerns. The EWG researchers found an average PCB level of 27.3 ppb in the ten fish studied with highest levels in the salmon that was farm raised in Scotland. This was over 5 times higher than the level of PCBs found in a sampling of wild salmon.

These studies, done on relatively small numbers of fish, had their findings confirmed in a subsequent study done on over 700 salmon (totaling approximately 2 metric tons of farmed and wild salmon) from around the globe. Thirteen persistent chlorinated chemical pollutants were found in significantly higher levels in farmed salmon than in wild salmon. The only compound that did not reach statistical significance was lindane which was still higher in farmed than wild salmon. The four compounds with the greatest differences were PCBs, dioxins, toxaphene and dieldrin. The least contaminated fish samples came from Washington State and Chile still had significantly higher levels of PCBs, dioxins and dieldrin. The most contaminated farmed salmon came from Scotland and the Faroe islands.

The researchers were wise enough to also test the fish pellets that these farmed salmon were fed. They tested samples of salmon feed from global suppliers that account for 80% of all salmon feed sold world-wide, and found the source of the salmon’s contamination. The levels of these toxins in the fish were directly related to their presence in their feed. These pellets are made from smaller fish which have been contaminated with these pollutants. PCBs then build up in the salmon at levels about 20-30 that of their environment and feed.

Proponents of aquaculture (fish farming) are ready to point out that these levels are not necessarily a health hazard. However, studies that have looked at the effect of PCB intake on offspring appear to contradict that stance. There have been a number of studies that have measured maternal levels of PCBs and then followed the offspring for a number of years. Their findings are consistent that the higher the serum levels of maternal PCBs the greater the neurological deficits in the offspring.

In 1979 rice bran cooking oil that was contaminated with PCBs was used for a number of months in Taiwan. Children born to exposed mothers (including children born up to 6 years after the exposure) were then followed for persistent neuro-psychological problems. At 6 years post exposure the offspring scored an average of 6 IQ points lower than their older siblings who were themselves exposed to the PCBs. In addition they exhibited 23% greater rates of problem behavior and 15% greater levels of activity than their controls. By age 17 these children still showed significantly greater problems with behavior and had a persistent IQ reduction averaging 3 IQ points. This was true even in children born to mothers up to 6 years after their exposure.

A study done in Michigan followed the development of children born to mothers who had consumed fish from Lake Michigan which were polluted with PCBs. These were not farm-raised fish with 4-16 times the level of PCBs found in wild fish. Even though the average maternal serum levels of PCBs were only mildly higher than US averages, these children did show persistent effects. By age 11 these children showed reduced total IQ, and especially verbal IQ, that became more pronounced as the maternal levels of PCBs increased. IQ drops in the group with the highest maternal serum level averaged 6.2 IQ points. This reduction in IQ is similar to that found in children with elevated blood lead levels. The children with in-utero exposure had poorer verbal and reading comprehension, poor “freedom from distractibility”, reduced short and long-term memory, and decreased ability to organize and plan. These children were more than three times likely to perform poorly on testing and were at least two years behind their controls in reading skills. Fortunately levels of PCB in maternal breastmilk had absolutely no association with these neurotoxicity effects. It appears that these defects are developed secondary to PCB exposure in utero, not after delivery.

The alarming point of the ongoing Michigan study is that the mothers only had blood PCB levels slightly above the US average. It would not be hard to have much higher than normal PCB levels if one were to be eating farmed salmon on a regular basis. Even though no federal agency has put out a warning, I think it would be prudent to let all women for whom pregnancy is possible know that they should avoid all exposure to farmed salmon. Fortunately every grocery store seems to have cans of Alaskan Salmon that are readily available for use. With the highest EPA/DHA levels of any fish and a very low mercury and PCB levels, it provides one of the best sources of fish in the diet.

But what does one do if they have elevated PCB levels in their blood. As was found in the Taiwan study, children born up to 6 years after mom’s exposure still had problems. Since PCBs are fat-soluble, they tend to stay in the body for a long time and redistribute throughout adipose stores. Since the human body is not designed to easily get rid of fats or oils these compounds tend to bioaccumulate. Supplementation that helps to produce and dump bile (cholegogue and cholerectic actions) and have that bile be excreted from the body would be beneficial. Psyllium is still the only fiber that is known to actually increase the fecal bile content. But having patients undergo a program that combines low temperature sauna and colonic irrigations may be the best protocol to reduce levels of PCBs.

PCBs have also been associated in the medical literature with different cancers. One of my cancer patients had his PCB levels tested prior to going through our intensive cleansing program for a period of four weeks. He was retested twice as he continued to do a maintenance cleansing protocol. His initial program included 3 hours of low temperature sauna five days weekly for 20 session, that were followed by constitutional hydrotherapy and colonic irrigations. Supplementation was included as part of his cleansing program along with dietary changes. After the initial 20 sessions he did one colonic irrigation weekly for the following 18 months. Prior to starting his cleansing program he had 3 (out of 10 tested) PCBs present in his blood totaling 2.5 ng/ml (ppb). Eleven months later only 2 were present for a level of 1.4 ng/ml. Seven months after that none were detected! This rate of decline far outpaces the normal glacial reduction of PCBs in the serum (as highlighted in the Taiwan spill studies), showing that this cleansing method was clearly effective for this individual in reducing his body burden of PCBs.

While such cleansing programs are available to reduce the body burden of persistent chemical pollutants, it would be wiser to avoid exposures to them in the first place. For the sake of the children-to-be, the intake of all Atlantic salmon should be avoided.

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