On August 18, 2017, California’s Department of Pesticide Regulations (DPR) released an updated draft risk assessment for comments by the public on the popular agricultural pesticide chlorpyrifos. Farmers use chlorpyrifos to kill pests that attack a wide variety of crops including grapes, walnuts, oranges, almonds and cotton grown in California. In 2015, California farmers used more than 1 million pounds of chlorpyrifos on more than 60 crops. About 5 million to 10 million pounds of chlorpyrifos are used annually on crops nationwide.
Under the new risk assessment, chlorpyrifos would be placed on a list of chemicals known to be harmful to humans. The new assessment would also prohibit the use of chlorpyrifos within 450 feet of schools or homes.
The moves run contrary to a recent decision by Scott Pruitt, Administrator of the U.S. Environmental Protection Agency, to end his agency’s effort to ban chlorpyrifos. Pruitt told Congress in June that his decision was based on “meaningful data and meaningful science.”
California officials, however, say that researchers are learning more about how the pesticide may harm the developing brains of unborn babies and young children. A UC Berkeley study found that seven-year-old children in the Salinas Valley who were exposed to high levels during pregnancy had slightly lower IQ scores than their peers. A Columbia University study showed similar effects at lower exposure. “New information in the scientific community leads us to believe the level of risk it poses is greater than previously known,” California EPA Secretary Matthew Rodriquez said in a statement. “The actions we are taking today reflect our commitment to the health and safety of all Californians, and the environment.”
Dow AgroSciences is the main producer of chlorpyrifos. It released a statement after Pruitt’s decision that “Dow AgroSciences remains confident that authorized uses of chlorpyrifos products offer wide margins of protection for human health and safety.”
Joel Nelsen, president of California Citrus Mutual, an industry advocacy group, said it will now be more difficult to produce food for consumers. “This is a solution looking for a problem,” Nelsen said. “This chemical has been a critical tool for years, without any problems.”
After DPR’s comment period closes, DPR’s updated draft risk assessment will be considered by a Scientific Review Panel comprised of nine scientists. The regulations could then go into effect in early October.
These actions by a California state agency serve as a reminder of the dynamic situations faced by pesticide producers and users as they attempt to navigate a complex web of state and federal agencies involving products that can cost billions of dollars and numerous years to develop.