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Whole GM Toxins in Human and Foetal Blood – GM crops/imports must halt

Immediate release (20 May 2011)

Calls to Pete Riley 07903 341 065.

New research from Canada has found a Bt toxin produced by GM insect resistant crops in the blood of women and clear evidence that it was passed to foetuses. [1]

Pesticides used on GM herbicide tolerant (HT) crops were also detected.

GM Freeze is calling for an immediate halt to GM Bt crop cultivation and imports of Bt GM food and feed until the findings are properly evaluated and further study confirms product safety. [2]

The same Bt toxin as detected by the researchers is present in Mon810 maize, which has EU cultivation approval but is currently banned in France, Germany, Austria, Hungary, Luxemburg and Greece.

Regulators advise that no GM protein survives intact in the intestinal tract to enter the blood stream [4], so the detection of intact Cry1Ab toxin in human blood is of great significance.

The new study was carried out by a team at Sherbrooke University Hospital in Quebec and has been accepted for publication in the peer reviewed journal Reproductive Toxicology. The team took blood samples from 30 pregnant women prior to delivery, 30 samples from umbilical cords immediately after birth and samples from 39 non-pregnant women who were undergoing treatment. All the women were of a similar age and body mass index, and none worked with pesticides or lived with anyone who did.

The results show that the toxic Bt protein Cry1Ab was present in blood serum from all three sources (93% of pregnant women, 80% in umbilical blood and 67% of non-pregnant women). The researchers suggest that the most probable source of the toxin is GM food consumed as part of a normal diet in Canada, where GM presence in food is unlabelled. The Canadian scientists have not speculated on any health effects from the presence of Cry1Ab protein as this was beyond the scope of their study.

The findings add to concerns about the toxicity and potential allergenicty of Bt proteins expressed by many scientists. [3]

In a statement issued in July 2007 the European Food Safety Authority stated:

A large number of experimental studies with livestock have shown that recombinant DNA fragments or proteins derived from GM plants have not been detected in tissues, fluids or edible products of farm animals such as broilers, cattle, pigs or quails.

This was subsequently adopted as the official advice of the UK’s Food Standards Agency in “Transfer of GM material from feed” [4].

Pete Riley of GM Freeze said:

This research is a major surprise as it shows that the Bt proteins have survived the human digestive system and passed into the blood supply – something that regulators said could not happen.

The study throws into serious doubt the validity of the risk assessment carried out on Bt crops, which always assumed it would be destroyed in the gut. Here there is also evidence that it has been passed on to foetuses.

Regulators need to urgently reassess their opinions, and the EU should use the safeguard clauses in the regulations to prevent any further GM Bt crops being cultivated or imported for animal feed or food until the potential health implications have been fully evaluated.

GM techniques repeatedly produce unexpected outcomes. This is yet another adding to the worry that its presence in the food chain is based on partial information and false assumptions.

Twenty-four types of GM maize and cotton containing Bt GM traits have been granted approval for importing into the EU and one can be grown (Mon810 maize). [5]

The researchers also looked for, and found, two herbicides used on GM herbicide tolerant crops in blood samples. Glyphosate is used on Monsanto Roundup Ready (RR) crops and Glufosinate on Bayer’s Liberty Link (LL) crops. Both were found in the non-pregnant women, as was glufosinate’s metabolite 3-MMPA. The researchers did not speculate about potential health impacts, as this was beyond the scope of their study, although concerns about the safety of both weed killers have been repeatedly raised by other scientists since their use on GM crops has increased their use. [6] Scientists are particularly concerned that the studies done to demonstrate the “safety” of glyphosate were not long enough to ensure there are not long-term or cumulative health impacts of long-term exposure in food.

Use of glyphosate in South America and the US has escalated dramatically since GM crops were approved in the mid 1990s, despite the assurances from the GM industry that the intention of the crops is to reduce pesticide use. As a result of the increased use of, and dependence on, a single herbicide, weeds resistant to glyphosate have developed. [7]

Safety concerns about both products have been growing since the introduction of GM herbicide tolerant crops, including links to Parkinson’s disease and cancer in the case of glyphosate. [8] Residues of these herbicides in food are infrequently monitored, and the maximum permitted residue level for crops directly sprayed with glyphosate, such at GM HT crops, were raised over 200 tines in the 1990s.

Pete Riley said:

These weed killers are used directly on the growing crops close to harvest, so there is no surprise that they can pass along the food chain and into people. The long-term health implications of prolonged exposure to such residues need to be properly investigated and there is very strong case for suspending their use right now.



[1] Aziz A. and Leblanc S., 2010, Reproductive Toxicology, accepted 13 February 2011 Currently available online or from GM Freeze.

[2] See GM Freeze media briefing.

[3] Seralini G-E., Mesnage R. Clair E., Greese S., Spiroux de Vendômois J.ann Cellier D., 2010. Environmental Sciences Europe 2011, 23:10, see

[4] See

[5] See GMO Compass

[6] For instance see Benachour N and Séralini G-E, 2009. Glyphosate Formulations Induce Apoptosis and Necrosis in Human Umbilical, Embryonic, and Placental Cells, Chemical Research in Toxicology Vol22 No1 pp 97-105 available from

[7] See Resistance is Growing: GM herbicide tolerant crops and resistance in weeds