Lola Gayle, STEAM Register
According to the Associated Press (AP), Dow Chemical is pushing the Trump administration to ignore the findings of federal scientists who point to a family of widely used pesticides as harmful to about 1,800 critically threatened or endangered species — namely chlorpyrifos.
“Lawyers representing Dow, whose CEO is a close adviser to President Donald Trump, and two other manufacturers of organophosphates sent letters last week to the heads of three of Trump’s Cabinet agencies. The companies asked them “to set aside” the results of government studies the companies contend are fundamentally flawed,” the news agency said.
Follow the money
“Dow Chemical wrote a $1 million check to help underwrite Trump’s inaugural festivities, and its chairman and CEO, Andrew Liveris, heads a White House manufacturing working group.
“The industry’s request comes after EPA Administrator Scott Pruitt announced last month he was reversing an Obama-era effort to bar the use of Dow’s chlorpyrifos pesticide on food after recent peer-reviewed studies found that even tiny levels of exposure could hinder the development of children’s brains. In his prior job as Oklahoma’s attorney general, Pruitt often aligned himself in legal disputes with the interests of executives and corporations who supported his state campaigns. He filed more than a dozen lawsuits seeking to overturn some of the same regulations he is now charged with enforcing.”
Honey bees worldwide face an uphill battle in their fight for survival. While colony collapse disorder is a major peril for our pollinating friends, pesticides are more and more being recognized as an increasing threat.
According to researchers, even small doses of one of those pesticides — namely chlorpyrifos — can result in honey bees suffering learning and memory deficits. This could be a potentially serious threat to their success and survival, researchers from New Zealand’s University of Otago suggest.
For their study, the researchers collected bees from 51 hives across 17 locations in the province of Otago in Southern New Zealand and measured their chlorpyrifos levels. They detected low levels of pesticide in bees at three of the 17 sites and in six of the 51 hives they examined.
Back in the lab, they fed other bees with similar amounts of the pesticide and put them through learning performance tests.
Study lead author Dr. Elodie Urlacher said they found that chlorpyrifos-fed bees had worse odor-learning abilities and also recalled odors more poorly later, even though the dose they ingested is considered to be “safe.”
“For example, the dosed bees were less likely to respond specifically to an odor that was previously rewarded. As honey bees rely on such memory mechanisms to target flowers, chlorpyrifos exposure may be stunting their effectiveness as nectar foragers and pollinators,” Dr. Urlacher said.
The study identified the threshold dose for sub-lethal effects of chlorpyrifos on odor-learning and recall as 50 picograms of chlorpyrifos ingested per bee, she said. “This amount is thousands of times lower than the lethal dose of pure chlorpyrifos, which is around 100 billionths of a gram. Also, it is in the low range of the levels we measured in bees in the field.”
“Our findings raise some challenging questions about regulating this pesticide’s use. It’s now clear that it is not just the lethal effects on bees that need to be taken into account, but also the serious sub-lethal ones at minute doses,” Dr. Urlacher concluded.
The study, funded by the Marsden Fund of New Zealand, is published in the Journal of Chemical Ecology.
Note: Chlorpyrifos is used around the world to control pest insects in agricultural, residential and commercial settings. Chlorpyrifos was introduced in 1965 by Dow Chemical Company and is known by many trade names, including Dursban and Lorsban. It is moderately toxic to humans and was banned from home use in the United States in 2001. Despite this, it still remains one of the most widely used organophosphate insecticides in the United States.