LOS ANGELES — California regulators moved Wednesday to ban chlorpyrifos, a controversial pesticide used on almond, citrus and grape crops in the nation's largest agricultural state.
California's planned ban follows Hawaii and New York announcing similar moves against chlorpyrifos, a widely used chemical in farming that environmentalists claim is harmful to children and farmworkers.
Chlorpyrifos is manufactured by DowDuPont, which has insisted the pesticide is safe. Dow has lobbied the Trump administration to keep chlorpyrifos available for crops.
California plans to phase out the use of the pesticide statewide in a process that could take up to two years. New York lawmakers approved a ban April 30 that would end the use of chlorpyrifos in the state by 2021, while Hawaii's ban, announced last year, won't take effect until late 2022.
"California's action to cancel the registration of chlorpyrifos is needed to prevent the significant harm this pesticide causes children, farm workers and vulnerable communities," Jared Blumenfeld, secretary of the California Environmental Protection Agency, or CalEPA, said in a statement. "This action also represents a historic opportunity for California to develop a new framework for alternative pest management practices."
According to CalEPA, "the decision to ban chlorpyrifos follows mounting evidence, including recent findings by the state's independent Scientific Review Panel on Toxic Air Contaminants, that the pesticide causes serious health effects in children and other sensitive populations at lower levels of exposure than previously understood. These effects include impaired brain and neurological development."
In April, CalEPA regulators formally listed chlorpyrifos as a "toxic air contaminant," meaning the state believed it "may pose a present or potential hazard to human health." It said the move was done "to protect the health of farm workers and others living and working near where the pesticide is used."
CalEPA said Wednesday that chlorpyrifos use has declined in California in the past decade as farmers "have shifted to safer alternatives." It said use of the pesticide dropped more than 50% from 2 million pounds in 2005 to just over 900,000 pounds in 2016.
In March 2017, the Trump administration moved to show its support for chlorpyrifos. Then-U.S. Environmental Protection Agency Administrator Scott Pruitt rejected an attempt to ban the pesticide for use on food crops such as fruits, vegetables and nuts.
The largest agricultural market currently for chlorpyrifos is corn, according to the agency.
In 2016 the federal EPA, under President Barack Obama, moved to restrict use of chlorpyrifos after being petitioned by several environmental groups. Dow challenged the agency, saying its "assessment lacks scientific vigor."
In supporting chlorpyrifos, Dow previously has said "growers face limited or no viable alternatives to chlorpyrifos. When an outbreak of a new pest occurs, growers look to chlorpyrifos as a proven first-line of defense."
DowDuPont did not immediately reply to CNBC's request for comment Wednesday.
Chlorpyrifos is used in more than 90 countries. Most household uses of the chemical ended in 2000, but it has remained popular in farming.