Thursday, February 12, 2015

Neonics Questioned

Neonicotinoids are now the most widely used insect killers, and their safety to beneficial insects remains in question. “Neonics” are used to control pests in soybeans, cotton, and corn crops. The use of neonicotinoid insecticides coincides with the massive die-off of honey bees in Europe and North America. This means that the use of these new insect poisons and the deaths of bee colonies occurred at the same time. This timing alone does not mean that the insecticide killed the bees. However, nothing has cleared the neonicotinoids; Environmental Protection Agency scientists and others suspect that these insecticides are contributing to the colony losses. If they are contributing to the bee colony deaths, the situation will continue as long as these insecticides are being used. A number of studies are looking at neonicotinoids. The International Union for Conservation of Nature reviewed 800 peer-reviewed reports and prepared a Worldwide Integrated Assessment (WIA) of their findings, http://www.iucn.org/news_homepage/?16025/Systemic-Pesticides-Pose-Global-Threat-to-Biodiversity-And-Ecosystem-Services. They concluded, “In reviewing all the available literature rather than simply comparing one report with another, the WIA has found that field-realistic concentrations of neonics adversely affect individual navigation, learning, food collection, longevity, resistance to disease and fecundity of bees.” Meanwhile, EPA scientists noted in a memorandum, http://www.panna.org/sites/default/files/Memo_Nov2010_Clothianidin.pdf, involving the neonicotinoid insecticide Clothianidin that its “major risk concern is to nontarget insects (that is, honey bees). Clothianidin is a neonicotinoid insecticide that is both persistent and systemic….Clothianidin is highly toxic on both a contact and an oral basis.” The scientists site incident reports involving other neonicotinoid insecticides that “suggest the potential for long term toxic risk to honey bees and other beneficial insects.”

A promising study conducted in Arkansas found low levels of neonicotinoids in the reproductive parts of soybean and cotton plants—good news, since this is where honey bees gather nectar. Following the Arkansas study, Little Rock television reporter, Sarah Fortner, interviewed Jon Zawislak and me. View the “Science with Sarah” episode at http://www.thv11.com/videos/news/local/2015/02/06/23011219/. That’s Sarah and me examining a honey bee hive.
--Richard

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