The Environmental Protection Agency is considering a petition from farm worker and public health advocates to ban pesticide spraying near schools, hospitals and child care centers. Part of the evidence they cite comes from California, the nation's largest agricultural producer, and a state where pesticides carried from the fields by winds sicken hundreds of people each year.
Nancy Lara, 10, and her brother Brian, 8, were drenched by pesticides last spring as they stood at their bus stop, a patch of dirt on the edge of a vineyard in central California.
The Lara children noticed white clouds billowing out behind a tractor just across the road. Nancy says they tried to hide inside a cluster of vines at the bus stop.
"We thought the tractor wouldn't get us, but it did," Nancy says.
The approaching bus driver saw the pesticide clouds and pulled over to prevent the 50 other students from breathing in the fumes. She eventually picked up Brian and Nancy.
"And then I told the bus driver that I wasn't feeling good, like I was feeling sick. My head heart, I wanted to throw up and everything," Nancy says.
School officials called an ambulance, and the kids were sent to the hospital where they were treated for pesticide exposure. They eventually recovered, but nine months later, the Fresno County Agricultural Commission hasn't issued the fines to the vineyard owner and is still investigating the case.
That incident is one of seven "pesticide drift" cases involving school buses in the farm-rich San Joaquin Valley over the last year.
"Any incident involving pesticide drift is problematic," says Mary Ann Warmerdam, a former lobbyist for the California Farm Bureau who now heads the state's Department of Pesticide Regulation.
"It's illegal, and we have to do better. Having said that, we do have the human condition to contend with, and mistakes do happen," Warmerdam says.
She says California has the toughest pesticide rules in the nation, and there are very few accidents.
"If you take into account the thousands of applications that occur in California every year, we still have a remarkably compliant agricultural sector," Warmerdam says.
Over the last few years, an average of 37 pesticide drift incidents a year have made people sick in California.
But Teresa de Anda of Californians for Pesticide Reform says most incidents aren't even reported.
"Everywhere I go to all the little rural communities, everybody has a story to tell about being drifted on by pesticides — that they were outside barbecuing or they were having a birthday party," de Anda says. "It just happens so commonplace, people don't report it."
Ten years ago, de Anda was one of about 180 residents exposed to a soil fumigant that drifted into homes in the town of Earlimart. The fire department took those who were vomiting or ill to the middle school football field, asked them to strip down and blasted them with fire hoses.
"When I think back to that night, it was just horrible," de Anda says.
These kinds of high-profile incidents pushed California lawmakers to pass new pesticide drift legislation in 2004. Among other things, the law says growers must pay medical bills for pesticide drift victims who don't have health insurance or workers comp. So far, due to lengthy appeals and an unclear enforcement process, no grower has paid under that law.
And since it took effect, the number of pesticide drift incidents statewide doesn't seem to have changed much. Efforts to introduce new legislation to address the issue haven't been successful.
Growers admit mistakes happen, but say they're making every effort to prevent pesticide drift. Some California farmers have launched a new initiative called "Spray Safe."
About 300 farmers gathered recently to learn about a voluntary checklist of things growers can do to prevent pesticide drift, like putting flags up to let neighbors know when spray rigs are in the fields. San Joaquin County Farm Bureau President Phil Brumley told the crowd if a drift affects a neighbor's crop, you can come up with some kind of compensation.
"But in the case where it's people, we need to think about human health and safety first, and that's what this is about," Brumley said.
Growers aren't interested in more regulation though. They say improving communication with neighboring communities is the best solution.
Meanwhile, environmental advocates are hoping the EPA will restrict spraying of certain pesticides near areas where children congregate. The agency is also considering new labeling guidelines for chemicals to warn against the dangers of pesticide drift. It's accepting public comment on both proposals this month.