On 27 November 2005, Dr. Mae-Wan Ho wrote to a number of national and international agencies on behalf of the Independent Science Panel [1] regarding the powerful immune response in test animals fed genetically modified (GM) peas, demanding a ban on all GM food and feed until proper assessment on the immunogenicity of all transgenic proteins has been carried out.
Ho reported the scientific study [2] in detail, which showed that a previously harmless bean protein transferred to pea provoked a debilitating immune response on account of post-translation processing of the protein in the pea plant which differs from that in bean. As practically every transgenic protein involves a transfer of the protein to a different species, all transgenic proteins are potentially capable of provoking such immune reactions, unless proven otherwise.
The Canadian Food Inspection Agency (CFIA) responded on 19 December, and the United States Department of Agriculture Animal and Plant Health Inspection Service (USDA-APHIS) replied on 22 December.
The reply from USDA-APHIS explained that while it works in partnership with the Food and Drug Administration (FDA) and the Environment Protection Agency (EPA) “to ensure that the development, testing, and use of the products of biotechnology occur in a manner that is safe for plant and animal health, human health, and the environment,” it is the FDA that “is responsible for ensuring that all plant-derived foods and feeds, including those developed through biotechnology are safe and properly labeled.” And while USDA-APHIS appreciate the information provided regarding the study, the issues addressed are primarily matters of food and feed safety, which “fall under the regulatory authority of FDA”, and suggested that the FDA be contacted directly.
The CFIA responded with a detailed discussion on the concept of “substantial equivalence” and the procedures used by CFIA, as recommended by the Food and Agriculture Organization (FAO) [3, 4], to evaluate toxic food impacts such as allergenicity. The current reply is mainly addressed to the CFIA.
Many commentators have exposed the concept of substantial equivalence as thoroughly unscientific, starting with Ho and Steinbrecher [5], who showed how the concept effectively allows the approval of GM crops without the necessary safeguards to human and animal health or the environment.
Similarly, the tests for allergenicity, which include amino acid sequence similarities, heat stability and digestibility (mainly under simulated gastric conditions), have already been rightly criticized as inadequate [6, 7]; and more importantly, do not include the tests carried out on the transgenic pea in the new study. Even the FAO/WHO reports [3, 4] recommended a combination of additional methods for assessing allergenicity, such as binding tests of antisera from allergic patients, and animal exposure studies.
CFIA stated: “Characterization data provided by the proponent is generated with genetically stable, modified lines that are representative of the final product.” Unfortunately, there is no evidence that the transgenic lines are genetically stable. In 2003, French government scientists found that in all five transgenic lines already commercialised, the GM insert has rearranged since characterized by the company for commercial approval [8-10].
These considerations point to the inadequacy of the regulatory regime for GM crops.
Indeed, the USDA has just been criticised in a report issued by its own Inspector General for failing to regulate the field trials of GM crops [11, 12]. The report found that USDA “lacks basic information about the field test sites it approves and is responsible for monitoring, including where and how the crops are being grown, and what becomes of them at the end of the field test.” It also said that weaknesses in regulations and in the internal management controls at the USDA “increase the risk that genetically engineered organisms will inadvertently persist in the environment before they are deemed safe to grow without regulation.”
At the end of the long letter, CFIA noted: “You cited a recent publication by Prescott et al regarding GM field peas in your message. We consider this study to be an example of how the appropriate methods are at hand to identify allergenicity concerns associated with newly expressed proteins in plants.” It did not say that such methods are actually being used by the CFIA, however.
It is arguable whether the tests carried out by Precott et al are adequate for safeguarding animal and human health, but at least they succeeded in detecting the allergic/hypersensitive reactions to the transgenic protein. But, none of the transgenic proteins in commercialized food and feed has been subjected to such tests. CFIA and other regulatory authorities not only should use similar tests for assessing every new GM crop, it should retrospectively apply the tests to all already commercialized GM crops.
That is why, in the light of the new evidence, a ban on all GM food and feed must be imposed as a matter of urgency, until and unless the transgenic proteins are proven safe by adequate tests on immunogenicity.
Article first published 04/01/06
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