Chlorpyrifos Celebrates its 50th Year

09/28/2015 -

Some fifty years after its commercial introduction, chlorpyrifos continues to be one of the most widely-used active ingredients for agricultural insect control in the world. First registered in the U.S. in September 1965, chlorpyrifos is today approved in nearly 100 countries worldwide. More than 50 crops, many of which are dietary staples for entire nations, are protected from insect infestation with chlorpyrifos.

The origins of chlorpyrifos are found in research on synthetic phosphorous-containing insecticides in the late 1940s within The Dow Chemical Company. Dowco™ 179 was the most promising product to emerge from this program, with broad-spectrum activity against mosquitoes, cockroaches, and a variety of household and turfgrass pests. It received U.S. and French patents in 1962 and soon become known by its common chemical name “chlorpyrifos.”

The first request for registration was submitted to the U.S. Department of Agriculture in March of 1965, with Dursban™ 2E receiving approval six months later, for professional-use control of pests in turfgrass. Development of chlorpyrifos for agricultural use occurred during the late 1960s and early 1970s. Expansion was aided by several key properties including its broad-spectrum activity, short residuality on foliar surfaces and moderate residuality in soil, and low mammalian toxicity.

In the half century since chlorpyrifos was first registered, it has been one of the most thoroughly-studied insecticides on record. More than 5,000 scientific studies have been conducted on potential health and environmental effects. Much of this research has been groundbreaking in nature and findings have stimulated methodological improvements related to human safety testing and environmental impact assessment.

Dow AgroSciences (DAS) continues to serve as a primary manufacturer and supplier of chlorpyrifos-based products. A continued commitment to innovation has resulted in a new generation of brands including sophisticated formulations as Lorsban 75WG and Lorsban Advanced as well as combination products such as Cobalt Advanced and Nurelle D


DAS is pleased with the contributions that 50 years of chlorpyrifos availability has provided for sustaining effective farming and protecting food and fiber production on a worldwide basis for a growing population. We express appreciation to all of our employees, customer channel partners, and the millions of farmers for their strong and sustained support of this most beneficial molecule. Happy 50th chlorpyrifos!

Related: Benefits & Use » How It's Used » Impact




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