State pesticide regulators are seeking to limit one of farming's most widely used bug killers over concerns that it poses a threat to the public and environment.
Chlorpyrifos is used on more than 60 different crops in California, but the state's Department of Pesticide Regulation wants to make it a restricted material, meaning county agricultural commissioners can approve or deny its use depending on conditions.
State officials say that while chlorpyrifos is an effective tool at killing a variety of pests, it also tends to move from the area of application by air or water.
Exposure to the chemical can cause nausea, dizziness, and at high levels can cause respiratory paralysis. It's also toxic to freshwater fish.
DPR records shows that 136 people were exposed to chlorpyrifos drift between 2001 and 2011. Some of the exposure may have been the result of applicators not following the label correctly. In Fresno County, four people were affected in 2009 by drift from a neighbor's property and in 2007, 26 people in Tulare County reported symptoms after a nearby almond orchard was sprayed.
The proposed regulation, which begins a 45-day public comment period Friday, would require that anyone applying the chemical must be a trained and licensed professional who also must get a permit from the county commissioner before spraying. The county commissioner will also look at site-specific conditions, such as weather and proximity to homes, schools or other public buildings to prevent drift.
A county commissioner can impose other conditions to help reduce any other risks.
"What we try and do is to head off any potential problems," said Tom Tucker, Tulare County's agriculture commissioner. "And if need be, we can deny the permit if the conditions are not right."
In the central San Joaquin Valley, the bug-killing chemical is applied on dozens of crops including, grapes, almonds, and citrus.
West-side farmer Don Cameron says he doesn't use the pesticide often, but when he does, it is very effective.
"It is one of the older chemicals, and I understand why the state is looking at it," Cameron said. "But there are times when it is the best choice for the problem we are dealing with."
A coalition of environmental groups is pushing for a complete nationwide ban, not just restrictions on its use.
The groups sued the federal Environmental Protection Agency this week seeking to remove chlorpyrifos from the market.