SACRAMENTO — Don’t expect a renaissance for chlorpyrifos use among California growers now that the U.S. Environmental Protection Agency has declined to ban the pesticide.
So opines Pete Goodell, a University of California Cooperative Extension pest control adviser who held a series of grower workshops last year on the proposed ban.
Some growers may be glad to still have chlorpyrifos available when nothing else works, but in many cases farms have already found alternative treatments and preventive measures, he said.
“People have shifted away for a number of reasons,” said Goodell, an associate director of the UC’s Statewide Integrated Pest Management Program. “One is that some of the crop may require contracts that say you aren’t going to use certain products. For others, with the restrictions and regulations, they’ve moved away because it’s not as difficult to use other products.”
In California, chlorpyrifos is used to tackle pests that can destroy some 60 different crops, including almonds, alfalfa, walnuts, oranges, cotton and grapes, explained Charlotte Fadipe, spokeswoman for the state Department of Pesticide Regulation.
Use of the pesticide has been declining over the last decade, from more than 2 million pounds in 2005 to about 1.3 million pounds in 2014, the last year for which data is available, Fadipe said.
Growers were sent scrambling for alternatives when the EPA announced a plan to revoke food residue tolerances for chlorpyrifos, which is produced by Dow AgroSciences and acts as a contact or stomach poison to pests. The agency took comments in the fall of 2015.
But on March 29, new EPA Administrator Scott Pruitt said the agency was denying a petition by environmental groups to ban the pesticide’s use in agriculture. The EPA banned home use of chlorpyrifos in 2000 and ordered buffer zones around sensitive sites, such as schools, in 2012.
In recent years, California has put significant controls on the use of chlorpyrifos, requiring training, licensing and local county approval for anyone who uses it. Growers must explain to their county agricultural commissioner when, where and how they want to use the pesticide, and counties require buffers of up to 150 feet between the user and a school, river or other sensitive site.
California’s rules remain intact, and the DPR “may put further restrictions in place if warranted,” Fadipe told the Capital Press in an email.
In 2014, the DPR contracted with the UC’s pest management program to create commodity-specific guidelines for using chlorpyrifos. Teams focused on its use on alfalfa, almonds, citrus fruit and cotton, identifying alternatives as well as instances when use of the chemical is critical to protecting the crop.
A resulting report by UC IPM examined other pest-control tactics, including pest-resistant varieties, mating disruption, field sanitation and other insecticides.
But in some cases, no alternatives were available. For instance, almond growers need chlorpyrifos to combat leaffooted plant bugs and stink bugs, which both feed on and damage developing nuts, scientists found.
“It’s still one of those tools … that’s good to have there in situations when you do need it,” Goodell said.
Several farm groups put out statements praising Pruitt’s announcement. California Citrus Mutual president Joel Nelsen said the decision shows that the EPA is taking more of a science-based approach to regulating pesticides.
Among chlorpyrifos’ uses for citrus growers is to battle the Asian citrus psyllid, which can carry the deadly tree disease huanglongbing.
National Council of Farmer Cooperatives president Chuck Conner said he hopes the decision “can serve as a roadmap as the EPA moves forward in assessing other crop protectants in the review and registration process.”
But the Center for Food Safety complained that President Donald Trump’s administration disregarded long-term studies from the EPA and National Institutes of Health concluding that exposure to chlorpyrifos could harm children’s brains.
“This reversal … is a frightening indicator that the new administration will stop at nothing to protect corporate interests,” said Andrew Kimbrell, the CFC’s executive director.