The problem could have been environmental, offered AquaBounty. Maybe the problems were caused by nutrient deficiencies, exposure to antibiotics, contaminants in feed, parasites, or water temperature. Yet, if that were the case, notes Hansen, we would also see a high rate of malformations in non-GE fish in 2005, and we do not. Both the diploid and triploid groups of non-GE fish performed well in 2005, with 98.7 percent and 89.0 percent showing no malformations, respectively. Hansen also dismissed AquaBounty’s assertion that the extra chromosomes in the triploid salmon were responsible for the 2005 data, as both the diploid and triploid GE salmon performed poorly, but the non-GE triploids performed quite well.
Despite the problems noted above, the FDA concludes from the data that, “Analyses of the behavior and gross external abnormalities of market size (1,000-1,500 g) AquAdvantage Salmon show no demonstrable differences from the comparator fish population.” One last flaw Hansen points out is the study’s examination only of adult fish, and not of fish in all life stages, beginning with the egg. The FDA, perhaps worried about this, and certainly worried about AquaBounty’s heavy culling of fish in early life stages (not to mention their lack of data on fish that were culled), called for a Durability Plan that includes “monitoring, data collection, and reporting of abnormalities observed under commercial production and grow-out conditions at the Panama facility where AquAdvantage Salmon will be reared” after the fish are approved and commercialized. Hansen feels this is insufficient, comparing it to allowing the fox to guard the henhouse and report if any chickens are being eaten.
Another area where the science is flawed is in AquaBounty’s examination of hormone levels in the fish. Of 73 fish tested (30 GE and 43 control), every single fish had growth hormone levels that fell below the detection limit. Hansen criticizes AquaBounty’s conclusion that there was no detectable difference in levels of growth hormone between GE and non-GE fish, comparing it to a cop with a radar gun that cannot detect speeds below 120 mph concluding the is no evidence of exceeding the speed limit. Additionally, only six of the 73 fish had detectable levels of T4 (a thyroid hormone), and only 17 had detectable levels of insulin like growth factor 1 (IGF1), a hormone that is potentially harmful to humans. Even with the small amount of data, the GE salmon that had detectable levels if IGF1 tested nearly 40 percent higher on average than the non-GE salmon with detectable levels of IGF1.
One last area to consider is the allergenicity testing of the GE salmon, as fish allergies are one of the eight most common allergies in the United States. For this, AquaBounty used sample sizes of six, testing GE diploids and triploids against non-GE diploids. They began by sending 18 blinded salmon fillet samples to a lab that treated them with liquid nitrogen to produce “frozen salmon-fillet homogenate.” Then they unblinded the samples and tested each individual sample with sera from humans with salmon allergies and measured the magnitude of the allergic reaction to determine the “allergic potency” of the sample. AquaBounty then converted the data into an undefined estimated measure it called “relative potency,” a term the lab was unable to define when asked by the FDA.
The FDA obtained the actual data tables from the test and concluded that, “The allergic potency of triploid [AquAdvantage] salmon is not significantly different from that of [the control group of non-GE] diploid salmon.” Again, Hansen took issue with this conclusion in light of the small sample size in the study, the unblinding of the samples, and the fact that the allergic potency of all but two GE salmon were higher than the highest value of allergic potency for non-GE salmon.
Hansen felt that, while the use of actual human sera to test allergenicity was useful, it was insufficient given modern scientific techniques available to assess allergenicity. Scientists are aware of many proteins that cause salmon allergies and they could easily have analyzed the molecular structure of the fish to determine if those proteins were present. Although there was one attempt to do this for one protein, the testing technique was so crude and flawed (some of the data submitted was upside-down!) even the FDA did not accept it.
Why Consumers Should Be Concerned
Given the flawed science used to justify the safety of AquAdvantage salmon, what happens now? Currently, the FDA is preparing for its public meetings: The first meeting on Sept. 19th will review the science; the second meeting on Sept. 21st will cover labeling issues and offer an opportunity for public comment. FDA will also accept written comments until November 22.
There are a few more issues for consumers to consider should the GE salmon come to market. Under current law, genetically engineered foods are not required to be labeled as such. In fact, the only labeling one can expect on a genetically engineered salmon fillet is country-of-origin labeling, which is required on most (but not all) seafood. Since all of the AquAdvantage will be produced in Panama, an uncommon location for farmed salmon, consumers can be on the lookout for — and avoid if they wish — salmon from Panama. The exceptions will be salmon sold in fish markets and processed salmon, such as smoked salmon, which do not require country-of-origin labeling.
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