A federal court order could ban a pesticide used by growers throughout San Luis Obispo County as soon as this month due to environmental concerns about its safety.
In a rebuke to the Trump administration, an appeals court in August ordered the U.S. Environmental Protection Agency to ban chlorpyrifos, a chemical that environmentalists say can damage the nervous systems of farmworkers, their children and even consumers.
The U.S. 9th Circuit Court of Appeals told the EPA to ban the substance within 60 days.
The ruling by the 9th Circuit is a major victory for environmentalists and a defeat for agricultural interests and the Trump administration, which had refused to ban the pesticide.
SLO County chlorpyrifos use
In San Luis Obispo County, chlorpyrifos-based pesticides are used to control pests from Cayucos to Nipomo, according to San Luis Obispo County Department of Agriculture data obtained through a California Public Records Act request.
The chemical was used 15 times on 311.5 acres in 2017. Most county growers selected Lorsban, a Dow AgroSciences brand, which they primarily applied in citrus groves, although some was used on peas, strawberries and wine grapes.
Joel Nelsen — president of California Citrus Mutual, a trade association that represents San Luis Obispo County growers — said chlorpyrifos-based pesticides help control ants and red scale insects, pests that look like round, hard dots.
Ants eat beneficial insects used to kill Asian citrus psyllids, a well-known fruit tree pest, Nelsen said.
Although there are chemicals that can be used in place of chlorpyrifos, growers like to use a variety of pesticides to prevent insects from developing a resistance to a particular substance, Nelsen said.
One benefit of the chemical, he said, is that it’s target-specific: “It’s still a tool that growers like as an alternative.”
A ban on chlorpyrifos would take one pest control option away from growers, Nelsen said.
“I think it’ll make citrus growers in San Luis Obispo County more vulnerable to Asian citrus psyllid,” he said.
Environmental safety concerns
After the appeals court ruled, the California Farm Bureau Federation’s government affairs manager, Jim Houston, said he anticipates a ban on chlorpyrifos will yield “significant impacts to food and fiber production.”
Lawyers for Dow AgroSciences disputed claims that the product is unsafe and argued that a ban on the pesticide would leave many farmers defenseless.
“For many crops, chlorpyrifos is the only effective pest management product available,” the Dow lawyers wrote in a court filing.
After the August ruling, the company said it’s considering its legal options and “will continue to support the growers who need this important product.”
Marisa Ordonia, an attorney with Earthjustice, a Seattle environmental law firm that worked on the case, said EPA scientists had concluded in 2016 that the pesticide was harmful to farmworkers and their children — and could be dangerous to those eating the foods grown with the chemical. She said children ages 1 to 2 years old were particularly at risk to a host of neurological problems.
The EPA study cited data from California regulators showing that chlorpyrifos was affecting air quality in three largely agricultural communities: Salinas, Ripon and Shafter.
In the late stages of the Obama administration, the EPA was in the process of banning the chemical. Shortly after President Donald Trump took office in 2017, then-EPA Administrator Scott Pruitt announced he was “reversing the previous administration’s steps” and would allow farmers to keep using chlorpyrifos.
In a 2-1 decision, the court rejected the EPA’s arguments, saying the agency hadn’t demonstrated with “reasonable certainty” that the chemical is safe.
The court declared there “was no justification for the EPA’s decision in its 2017 order to maintain a tolerance for chlorpyrifos in the face of scientific evidence that its residue on food causes neurodevelopmental damage to children.”
Ordonia said Earthjustice and other groups have been trying to ban chlorpyrifos since 2007. The plaintiffs in the case included the California Rural Legal Assistance Foundation.
“This is a huge victory,” Ordonia said. “The court said, ‘EPA, you have to follow the science ... and follow the law.’”
Chlorpyrifos was introduced in 1965 by Dow as an alternative to the controversial pesticide DDT, which was banned several years later.
As health concerns rose, the federal government negotiated a settlement with the chemical industry to eliminate its use in most residential settings in 2000, but it was still permitted in agriculture.
According to the EPA’s website, high doses of chlorpyrifos can cause nausea, dizziness and confusion.
A 2017 report in the Journal of Neurochemistry said exposure to the chemical can lead to “neurological deficits that range from cognitive impairments to tremors in childhood.”
A 2012 study led by Columbia University said pregnant women exposed to chlorpyrifos can give birth to children with low IQs and other issues.
Tighter SLO County regulations
California officials have tightened regulations for chlorpyrifos usage in the state, and its usage has fallen.
Farmers throughout the state applied just 900,000 pounds of chlorpyrifos in 2016, down from nearly 2 million pounds in 2005, according to the state Department of Pesticide Regulation.
Agency spokeswoman Charlotte Fadipe said the state has imposed certain restrictions on its application in recent years.
Chlorpyrifos-based pesticide use has declined greatly in San Luis Obispo County since 2006, due primarily to Central Coast Water Quality Control Board restrictions.
The agency began requiring additional monitoring and reporting for commercial growers after chlorpyrifos levels exceeded those safe for aquatic life in Arroyo Grande, San Luis Obispo and Oso Flaco creeks, according to a water board statement.
Although the chlorpyrifos levels were toxic to aquatic insects, they weren’t high enough to affect humans, the statement said.
“That kind of triggered a downward trend in use in San Luis Obispo County,” said Martin Settevendemie, county agricultural commissioner.