Researchers link glyphosate and other herbicides to antibiotic resistance | Pesticide Action Network
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Researchers link glyphosate and other herbicides to antibiotic resistance

For Immediate Release: March 24, 2015 

Contact: Paul Towers, Pesticide Action Network, 916-216-1082 

Researchers link glyphosate and other herbicides to antibiotic resistance, highlighting health risks of industrial agriculture 

An international research team led by New Zealand’s prestigious University of Canterbury has found that commercial formulations of commonly used herbicides — glyphosate (RoundUp), 2,4-D and dicamba (Kamba) — can lead to development of antibiotic resistance in disease-causing bacteria. These herbicides increased the tolerance of the sometimes-deadly E. coli and Salmonella bacteria to certain antibiotics critical in the medical treatment of bacterial infection. The antibiotics examined in the study include those found in commonly used medications, such as ampicillin, chloramphenicol, ciprofloxin and tetracycline. Exposure to RoundUp increased the bacteria's tolerance to kanamycin and ciprofloxacin. In some cases, increased susceptibility was also found. 

Tolerance to antibiotics developed when bacteria were exposed to the herbicides at concentrations comparable to those associated with typical application rates in agricultural fields. The results of the scientific study were published today in the American Society of Microbiology’s journal, mBio. Increased tolerance has implications for selecting for populations of bacteria that have resistance to antibiotics.  

In response to the study, PAN senior scientist Dr. Marcia Ishii-Eiteman, PhD, issued the following statement:  

The international scientific community has just sent us two very loud wake-up calls. Today’s latest finding that RoundUp, 2,4-D and dicamba can lead to antibiotic resistance in common disease-causing bacteria follows right on the heels of last week’s alarming report from the UN’s World Health Organization that glyphosate, the active ingredient in RoundUp, is a “probable carcinogen.”  

For decades, PAN and our partners have been warning U.S. policymakers and the agencies tasked with protecting our health and supporting farmers and rural communities that our near-total dependence on the herbicide-resistant GE crop model of industrial agriculture is a disaster in the making. This faulty system is epitomized by Roundup Ready corn, cotton and soybeans, as well as recently approved (and widely condemned) 2,4-D and dicamba-resistant seeds. The science emerging today sends a powerful rebuke to the U.S. Environmental Protection Agency (EPA) and U.S. Department of Agriculture (USDA) for their negligence in turning a deaf ear to these warnings for so many years.  

EPA’s decision whether or not to re-register glyphosate is expected later this year; these two new scientific reports on the direct and indirect health harms associated with glyphosate raise the stakes of this decision dramatically. Continuing with ‘business as usual’ means ongoing daily exposure in rural communities to a probable cancer-causing chemical — and is not an option. In light of these new studies, we call on EPA to to produce an action plan within the next 60 days, with an expedited timeline for regulatory action that will significantly reduce dependence on and exposure to glyphosate. The agency must also, as a matter of highest priority, immediately cancel its recent registration of Dow’s 2,4-D and glyphosate-containing product, Enlist Duo, and deny Monsanto’s application for dicamba use in GE cotton and soybean production.  

No farmer should have to choose between cancer striking his or her family and a decent living. Now more than ever, American farmers need support in shifting from today’s toxic, ineffective and unsustainable model of agriculture into one that is productive, ecologically resilient, healthy and safe. We recognize that such system-wide changes cannot happen overnight. But getting this urgently needed process started is essential, and requires leadership and a serious commitment at the highest agency level.  

Today we call on Agriculture Secretary Tom Vilsack to direct his agency to produce — within the next four months — a detailed plan of action with clear timeline and benchmarks for how USDA will spearhead a country-wide transition to least-toxic ecological weed management. The new plan must break the cycle of weed resistance that keeps farmers on a pesticide treadmill, and phase out reliance on health-harming herbicides like glyphosate, atrazine and 2,4-D. The time for action is long past due.” 

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