A FORMER top official of the US Environmental Protection Agency (US EPA) has warned that pesticide use for genetically modified (GM) crops is on the rise, along with the use of systemic neonicotinoid insecticides for corn.
In his article “Pesticide Use on Genetically-Engineered [GE] Crops” that was featured by the Environmental Working Group’s online AgMag recently, Dr. Ramon J. Seidler, once a senior scientist at US EPA, said glowing reports about the reduction of insecticide and herbicide use among GMO crops are based on “ancient data” since they did not include the situation after 2010, “when widespread resistance began to emerge in ‘superweeds’ and ‘superinsects.’”
Seidler’s criticism of GM crops come in the wake of the looming approvals by the US government of several new crops that have systemic neocotinoid pesticides.
Systemic neocotinoid pesticides are similar to the toxins produced by Bacillus thuringiensis (Bt) eggplant on the skin and are effective against the fruit and stem borers that attack eggplants and render up to 90 percent of crops unsuitable for human consumption.
Genes inserted into Bt eggplant produce the toxin that kills the insects once they bore into the skin. This genetically produced toxin is lethal to the stem borers but has no effect on humans.
In the case of Bt corn, up to 40 percent of Filipino farmers are now using the GMO variety after it was commercialized in 2003, said experts who met for a public dialogue on Bt eggplant and other GM crops at the Southeast Asian Regional Center for Graduate Study and Research in Agriculture (Searca) in Los Baños, Laguna, on October 21.
Searca Director Dr. Gil C. Saguiguit Jr. said no deleterious impact of Bt corn on human health and the environment had been reported since 2003 and this has led to the adoption of the GM variety, the first GMO to be approved for commercialization in Asia.
Assistant Agriculture Secretary Edilberto de Luna credited Bt corn for the increase in output, with the country achieving sufficiency in yellow corn compared to its being a perennial importer of 1 million metric tons (MMT) annually.
While Filipinos generally welcome GMOs, Seidler said caution should be foremost among farmers since the practice of coating seeds, including corn seeds, with systemic pesticides has emerged in the past 10 years and its safety has been under question by different groups opposed to GMOs.
“In the US, GE corn is planted on some 90 million acres, so the overuse of undesirable pesticides on this crop can have profound effects on the natural ecosystem, including beneficial organisms. GE corn makes up over 90 percent of US corn acreage as of 2014, with 76 percent ‘stacked’ with both insecticide producing [Bt] and herbicide tolerant [Roundup Ready] traits. The latter enables heavy use of the herbicide glyphosate on food crops,” Seidler said.
“Many of us are unaware that in addition to the ever-increasing spraying of glyphosate and the presence of genetically engineered insecticidal Bt toxin in every cell of every GE crop plant, massive amounts of other pesticides [herbicides, insecticides, fungicides] are applied to genetically engineered food crops. The continuing massive overuse of pesticides—along with the failure to use refuge-set asides, the failure of GE corn to produce desired levels of Bt toxin and financial incentives for corn-on-corn planting cycles—have collectively resulted in the selection of pesticide-resistant weeds and insects, leading to ever more pesticide applications,” he added.
Seidler warned that the entry of chemical companies that historically have produced DDT, PCBs, bovine growth hormone, Agent Orange, glyphosate products and, more recently, neonicotinoids, endangers the seed-production component of the world’s food-supply system.
“These corporations have a clear conflict of interest when it comes to reducing the numbers and concentrations of chemicals on crops, because any such reduction has an immediate impact on their financial bottom line. There is also a clear conflict of interest when it comes to altering farm management to avoid insect and weed resistance if it results in using fewer chemicals. As University of Nebraska entomologist Lance Meinke said, ‘economics are driving everything,’” Seidler said.
“The US Department of Agriculture has shown that since 1996, glyphosate use has increased some twelvefold during the GE crop era, with overall herbicide usage increasing by more than 500 million pounds.
Meanwhile, the agency has now documented weed resistance on some 60 million American farm acres,” Seidler revealed.
He added that there has been an increase in the use of insecticides by US farmers, with the demand skyrocketing in 2010, when pests and insects exhibited resistance to GMO corn.