By Dr Eva Sirinathsinghji
Institute of Science in Society
EXTRACTS: A meta-analysis on 19 studies confirms kidney and liver toxicity in rats and mice fed on GM soybean and maize, representing more than 80 percent of all commercially available GM food; it also exposes gross inadequacies of current risk assessment.
A team of independent scientists led by Gilles-Eric Séralini at Caen University in France carried out a meta-analysis combining the results of 19 previous studies , and their report concluded:
“From the regulatory tests performed today, it is unacceptable to submit 500 million Europeans and several billions of consumers worldwide to the new pesticide GM-derived foods or feed, this being done without more controls (if any) than the only 3-month-long toxicological tests and using only one mammalian species, especially since there is growing evidence of concern.”
Multiple organ abnormalities revealed on re-analysis
The nineteen feeding studies performed to date were performed by both industry and independent scientists on either Bt maize or RR soybean, which constitute 83 percent of commercially available GM food. The Bt maize varieties all contain a specific pesticidal protein from the soil bacterium Bt (Bacillus thuringiensis), one variety was also glufosinate herbicide tolerant; the RR soybean is tolerant to Roundup Ready (glyphosate) herbicide.
The data were re-analysed with new biological and statistical methods, including the meta-analysis. Meta-analyses allow a more objective appraisal of the evidence and provide a more precise estimate of a treatment effect, giving greater statistical power, and reducing the significance of false-positive or false-negative results.
Although none of the findings are new, the meta-analysis gives further strength to the previous evidence. Importantly, it found that nine percent of tested parameters were disrupted, which is almost double the five percent that could be obtained by chance alone.
Forty-three percent of significant abnormalities were found in the kidneys of males. The liver was more affected in females and the kidney was more affected in males.
Kidney pathology in animals fed RR soybean included significant ionic disturbances resulting from renal leakage. This is consistent with results from cell cultures treated with glyphosate  (see  Death by multiple poisoning, glyphosate and Roundup, SiS 42), suggesting that the presence of the herbicide in the GM food was responsible.
Rats fed Bt maize had significantly decreased kidney size as well as focal inflammation. This was acknowledged by the European Food Safety Authority (EFSA) even though they went on to approve the products.
Liver pathology of animals fed RR soybean included the development of irregular hepatocyte nuclei, more nuclear pores, numerous small fibrillar centres, and abundant dense fibrillar components, indicating increased metabolic rates. These features were consistent with previous findings in cell cultures treated with herbicides .
GM maize-fed animals showed significant abnormal blood protein levels, indicative of disturbed liver metabolism. Histopathological features were also found in some cases. Again, this was acknowledged by the EFSA.
Read the full post at I-SIS.