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An article about chlorpyrifos: serious risks to human health and the legal status in US

5 June, 2012
A Chemical of Concern. By Christopher Cook.onearth.org. May 30, 2012. It was banned from homes in 2000, but agriculture still sprays 10 million pounds of the pesticide chlorpyrifos each year. Luis Medellin has lived most of his 25 years in what he calls "a box of trees" — a trailer park surrounded by orange groves in California’s Central Valley, one of the most prolific agricultural regions in the world. His home lies about 20 feet from where growers regularly spray a pesticide called chlorpyrifos, which slays bugs and worms by attacking the critters’ central nervous systems.
An article about chlorpyrifos: serious risks to human health and the legal status in US
 Over the years, Medellin has seen the pesticide’s effect on humans, too. About twice a month during growing season, the pesticide trucks roll by, and the spray leaves a chemical taste in his mouth that makes him gag and sometimes vomit in the middle of the night.
"When they spray, you can’t get away from it. It’s everywhere," says Medellin, who works as a community organizer in the San Joaquin Valley town of Lindsay, a few miles from his trailer park. "Even when they spray a mile away you can really smell it. … Two or three days after the spray, you can still taste it." Medellin says he and many of the community’s 45 other residents get strong headaches after sprayings, along with burning and watery eyes, stomach aches, and skin rashes. His 8-year-old sister Katty Huerta has developed serious eczema and needs prescription skin cream to keep the itching from getting worse.
There’s extensive evidence that chlorpyrifos, derived from a World War II-era nerve gas, presents serious risks to human health. Although the chemical was banned by the EPA for use in homes in 2000, American agriculture still sprays more than 10 million pounds of chlorpyrifos on fields and orchards each year, putting farmworkers and nearby residents at risk. A 2004 study by the National Cancer Institute found that both lifetime and acute exposures to chlorpyrifos are "significantly associated" with incidence of lung cancer. In March 2010, a team from Columbia University’s Mailman School of Public Health published evidence of "a link between prenatal exposure to the insecticide chlorpyrifos and deficits in IQ and working memory" among kids at age 7. Even before that study, Columbia researchers had linked chlorpyrifos with neurodevelopmental problems. And in April, a new Columbia study was published indicating that children exposed to the chemical in the womb had anomalous structural changes in their brains throughout childhood.
Despite these concerns, the U.S. Environmental Protection Agency has refused for more than a decade to ban chlorpyrifos, rejecting petitions from groups including the Pesticide Action Network of North America and the Natural Resources Defense Council (which publishes OnEarth). Farmers still spray the chemical on citrus, corn, soy, table grapes, peaches, nectarines, and other fruits. And as a federal court case this March showed, chlorpyrifos gas is still being used on household products in violation of the EPA ban. The gardening company Scotts Miracle-Gro pleaded guilty to selling bird seed laced with the insecticide, violating 11 federal environmental laws. According to the EPA: "Scotts continued to sell the products for six months after employees warned management of the dangers of these pesticides. Until its voluntary recall of these treated bird foods in March 2008, Scotts illegally sold over seventy million units of insecticide-treated bird food." The firm offered to pay a $4 million settlement fine, along with $500,000 toward conservation efforts.
There is reason to believe the Miracle-Gro scandal may not be an isolated case. A 2009 survey of more than 1,100 homes by the U.S. Department of Housing and Urban Development and the EPA found that, despite the ban on residential use, 78 percent of homes sampled in 2005-2006 had "measurable levels"of chlorpyrifos (although whether that represents new spraying or residue from pesticides applied before the ban is unclear).
Medellin learned about "measurable levels" of chlorpyrifos in his own home starting in 2004, when the Pesticide Action Network of North America asked him to help families in his community measure pesticides in their bodies. Medellin’s urine tests came back with levels of the chemical that concerned his doctor. "I remember my mom’s face," Medellin says. "It was like someone had died." The doctor told him he was potentially at risk for cancer and sterility if the exposure levels continued. "This was sort of the beginning of my activism," Medellin recalls.
In September 2007, PANNA and NRDC petitioned the federal government to ban chlorpyrifos in all uses "because of serious threats to human health." Now, after more than four years and no reply to the NRDC petition, EPA is finally conducting a health risk assessment as part of its periodic review process. A decision on the fate of chlorpyrifos isn’t expected until 2015, an EPA spokeswoman told OnEarth. Health advocates say that’s too long to wait. In 2010, after three years of silence from EPA, NRDC and PANNA sued the government to force a quicker decision on the chemical’s use. Mae Wu, a staff attorney for NRDC, says the EPA has been "pretty much ignoring us for four years now — it’s taken a lawsuit to get them to pay attention. They just keep dropping the ball and ignoring all the concerns."
But there’s no shortage of evidence about chlorpyrifos’ ill effects — after all, it’s designed to kill by disrupting nervous system function. A July 2006 EPA memo on chlorpyrifos states: "Risks to children in schools and parks, both indoors and outdoors, are of concern to the Agency." Just one application of the pesticide, the memo said, "poses risks to small mammals, birds, fish and aquatic invertebrate species for nearly all registered outdoor uses. Multiple applications increase the risks to wildlife and prolong exposures to toxic concentrations." Likewise, studies cited by the National Pesticide Information Center — a collaboration between Oregon State University and the EPA — show that children exposed to elevated levels of chlorpyrifos are "significantly more likely to experience adverse effects, including developmental delays and disorders, attention problems, and attention-deficit/ hyperactivity disorder." Another study released this year by Mount Sinai Children’s Environmental Health Center concluded that prenatal exposure to organophosphate pesticides such as chlorpyrifos is "negatively associated with cognitive development, particularly perceptual reasoning, with evidence of effects beginning at 12 months and continuing through early childhood."
So why would EPA, which has acknowledged the dangers of chlorpyrifos, fail to take action? The agency refused multiple interview requests from OnEarth, but in a written response stated that the NRDC petition "raises many of the science issues that EPA has been examining during our ongoing re-evaluation of chlorpyrifos." The agency said it continues to study the pesticide’s safety with input from scientific experts and the public.
The EPA also gets plenty of input from the chemical industry, which has powerful friends on Capitol Hill. (Dow Chemical, which owns Dow AgroSciences, the top producer of chlorpyrifos, spent more than $8 million lobbying Congress last year alone — although it’s impossible to say how much, if any, of that was related to chlorpyrifos specifically.) Pesticide producers play an active role in shaping regulations over the chemicals they make.  At a 2010 meeting of the Pesticide Stewardship Alliance — a public-private "collaborative" sponsored by Dow AgroSciences, Monsanto, Bayer CropScience, and other firms —  the director of EPA’s Office of Pesticide Programs laid out his agency’s "strategic goals" in a PowerPoint presentation. One of the goals listed: "being an effective gateway to the pesticide market." Annual meetings between EPA and industry to discuss pesticide regulation are sponsored by pesticide advocates such as CropLife America and the Chemical Specialties Products Association. The pesticide companies "are involved in [pesticide regulation] all the time," says Jennifer Sass, a senior scientist with NRDC. "They’re filling the room — the only people in the room will be the chemical producers, growers that use the chemicals, and me."
But increasingly, doctors are speaking out about the risks from chlorpyrifos and other powerful pesticides. In a February 2010 letter to EPA Administrator Lisa Jackson, the top doctors at Mount Sinai School of Medicine urged the agency to "take deliberate steps to ban the use of chlorpyrifos for agriculture." Since the ban on home use, they said, Columbia University researchers have found that "chlorpyrifos-induced reduction in head circumference at birth" has  "disappeared" among children in urban areas. But children and farmworkers in rural areas like Lindsay remain at risk — a disparity that has some crying foul.
"They know the impact on people’s health, and they’ve banned it from people’s homes, but it’s still being used" in farm communities, says Medellin. Margaret Reeves, a senior scientist with PANNA, puts it more strongly: "If it’s not safe enough for people in urban areas, how the hell is it safe enough for rural areas? It seems like an obvious case of environmental injustice."

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