The Environmental Protection Agency (EPA) has rejected calls to ban one of the nation’s most widely used pesticides, which is manufactured by Dow Chemical (DOW) and described by scientists as dangerous to the health of farm workers.

Scientists allege that contact with chlorpyrifos (Lorsban), which has been used by farmers for decades to kill pests on crops and was prohibited for household use in 2000, poses risks to fetal brain and nervous system development and can lead to autism. In 2015, the EPA proposed to revoke all use of chlorpyrifos on farms, a call that has just been rejected by the agency’s new chief Scott Pruitt.

“We need to provide regulatory certainty to the thousands of American farms that rely on chlorpyrifos, while still protecting human health and the environment,” Pruitt said in a statement. “By reversing the previous administration’s steps to ban one of the most widely used pesticides in the world, we are returning to using sound science in decision making — rather than predetermined results.” (See also: Trump Rolls Back Auto Emissions Standards)

Pruitt’s decision was supported by The United States Department of Agriculture, which credited chlorpyrifos as an “important pest management tool” to ensure that the nation’s food supply is abundant and affordable.

More Good News for Dow Chemical

Dow Chemical, whose merger with DuPont has just been approved by EU regulators, was also pleased with the the EPA’s ruling. The company’s AgroSciences division patented the product and has long disputed claims that chlorpyrifos causes harm when used to kill crop-spoiling insects. (See also: EU Approves Dow’s Merger with DuPont.)

News that the long-running debate on whether to outlaw chlorpyrifos from use on farms has now been quashed should provide another boost to Dow Chemical’s share price. Investor confidence in the company has been on the rise since it became clear that its complicated merger with DuPont looks finally set to get the go ahead. (See also: Dow Chemical Short Interest Declines 88%.)

Mr Pruitt’s decision was condemned by environmental groups, many of which criticized the government for favoring major corporate companies over the health and safety of the nation’s families. The rejection of the pesticide ban is not likely to be revisited until 2022.

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