Perspectives on the GM Debate and Herbicide-Use Implications for Antibiotic Resistance

Last week, the World Health Organization’s IARC declared that glyphosate ‘probably causes cancer’, drawing strong responses from pro and anti GM groups alike. As the debate over GM crops and pesticide use persists in the wake of this announcement, NEFG’s Professor Carlo Leifert would like to draw your attention to two related publications.

The first is an exchange between Claire Robinson, of GMWatch, and Mark Lynas, a proponent of GM technology, published in The Independent as the final part of their week-long GM coverage. The email debate highlights key arguments on both sides and references key research supporting each (and sometimes both) perspectives. Mark repeatedly queries: “is there any scientific evidence that could change your mind on any aspect of GM?” And Claire responds (quite thoroughly) with:

“Regarding food safety, tests should include transcriptomics, metabolomics and proteomics analyses to identify changes caused by the GM process; long-term (2-year+ and multigenerational) feeding trials in rats; and dose escalation trials in human volunteers. After commercialization, monitoring is necessary. All tests should be carried out by independent scientists from a publicly administered fund of money contributed by the GMO company.”

The second publication focuses on consequences of herbicide-use, but rather than carcinogenic properties, the authors highlight implications for antibiotic resistance.  In the peer-reviewed article published by The American Society for Microbiology, Kurenbach et al. found that sub-lethal exposure to three different common herbicides (including glyphosate) changed antibiotic susceptibility in E.coli and Salmonella bacteria. Susceptibility increased with some antibiotic-herbicide combinations and decreased in others, but the authors highlight the importance of their research to the growing issue of antibiotic resistance:

“Increasingly common chemicals used in agriculture, domestic gardens, and public places can induce a multiple-antibiotic resistance phenotype in potential pathogens. The effect occurs upon simultaneous exposure to antibiotics and is faster than the lethal effect of antibiotics. The magnitude of the induced response may undermine antibiotic therapy and substantially increase the probability of spontaneous mutation to higher levels of resistance. The combination of high use of both herbicides and antibiotics in proximity to farm animals and important insects, such as honeybees, might also compromise their therapeutic effects and drive greater use of antibiotics. To address the crisis of antibiotic resistance requires broadening our view of environmental contributors to the evolution of resistance.”

Regardless of your position on the issue, the recent coverage of potential pesticide-use and GM crop ‘side effects’ certainly provide some interesting debate fodder!