The U.S. Environmental Protection Agency (EPA) estimates that between 10,000 and 20,000 pesticide poisonings occur annually among the nation's two million agricultural workers, with acute effects ranging from rashes and nausea to respiratory problems and death. Cumulative long-term exposures increase the risks of cancer, birth defects and neurological impairment.
As a primary safety measure, the EPA mandates the use of Personal Protective Equipment, or PPE, to minimize pesticide exposures. Yet the use of PPE -- gloves, goggles, hats, coveralls, boots -- is low among farmworkers, and intervention efforts have had only limited success in improving compliance.
"There are many reasons for this," Snipes says. Protective equipment may be difficult or uncomfortable to wear. It may slow the work, in a job where speed is of the essence. It is not always provided by employers, and even when it is, its use is not always enforced.
Below the surface, says Snipes, are other, cultural reasons. Over 80 percent of U.S. farmworkers are Latino, most coming from Mexico, so language can be a substantial barrier. But at least as important to understand, she says, are farmworkers' shared beliefs about risk.
Beliefs impact behaviors
"Anthropologists know that risk responses are embedded in a cultural framework," she explains. "I always tell this story about my grandmother. She taught me as a young girl that it's risky to wash your hands with cold water, that cold water is somehow associated with later developing arthritis.
"I'm an adult now, and fairly well-educated, and I know in my head that this is not the case. But if you ask me what I use to wash my hands, it's hot water. Because this is part of my belief system, something that was passed on to me. And it impacts my behavior.
"I'm interested in the same kind of phenomena among farmworkers. What are the widespread beliefs that are passed down regarding pesticides and exposure, and how do they impact behavior and, ultimately, health?"
She began as a graduate student at the University of Washington, following apple pickers in the Yakima Valley. Currently Snipes works mostly in the Rio Grande Valley in Texas. For periods of three months to a year, she latches on with a group of farmworker families as a participant observer, moving along with them from crop to crop.
"I have picked just about everything," she says. "Apples, cherries, hops, asparagus, broccoli, raspberries, onions, squash, watermelon, cotton…"
Along with picking produce, she's gathering data: conducting interviews and focus groups, administering surveys and epidemiological assessments, and collecting biomarkers of pesticide exposure. "I want to have a comprehensive view of what's happening in their lives," she says.
Snipes brings to the field a special understanding that goes beyond her academic training. "My own grandmother worked picking cotton," she says, "so I have some understanding of the hardships, and I have those stories to share."
Among her findings is a common belief that danger attaches to the physical form that a pesticide takes and not necessarily to the chemical compound itself. "So if it's wet, a spray that people can feel landing on their skin, it's seen as harmful, and there is great concern. If it's dry, however, there is little or no concern. They call it 'powder,' and consider it almost like dirt."
A similar distinction is made between hot and cold. "Just like my grandmother, many farmworkers believe that if you wash your hands with cold water you'll end up with arthritis, or rheumatism. This type of belief is very common cross-culturally," Snipes says, "but in this context, it may have health impacts."
In the field, she explains, where workers are given cold water both to drink and to wash the residues of pesticide powder from faces and hands, they may rather wait until they get home to a hot shower, believing that cold water is to be avoided, and that powders aren't really harmful anyway. "That decision means eight to 12 hours of additional exposure."
Finding solutions that work
Two sources of inspiration flank Snipes on the walls behind her: a small photograph of herself with Dolores Huerta, co-founder of the United Farm Workers; and a large, brightly colored rendering of Our Lady of Guadalupe, patron saint of campesinos, painted by a farmworker's son.Her ultimate goal, she says, is to translate her findings into an intervention strategy that improves farmworker health. "It's really about supplying people with practical solutions."
That means taking into account not only the cultural backstory but also the gritty realities of fieldwork. "Our population is severely below poverty level," she says. (Federal poverty level is $23,500 for a family of four; farmworkers average $10-15,000.) "And in many cases they are paid by how much they pick. A strong temptation, even for me, is to take off the extra clothes that slow you down -- because if you're slow you'll get fired and somebody else will replace you."
It can be suffocating wearing protective gear under the hot sun, she adds. And safety glasses tend to fog, making it difficult not only to see what you're picking but also to avoid snakes and other threats. "People are balancing these risks against the risk of exposure."
With a team of Penn State colleagues she recently tested a new multipronged strategy aimed at improving worker compliance. As Snipes explains, the intervention supplied workers with better PPE -- cooling fabrics, touch-sensitive gloves, non-fog lenses -- and also with tailored pesticide safety messages: frequent reminders about specific exposure risks. "We wanted to see how this combination might change behavior," she says.
One major challenge was how to communicate effectively with a mobile, low-literacy population. The answer, not surprisingly, was to adopt a mobile platform: the researchers gave farmworkers cell phones, enabling timely, two-way sharing of information. "We can use the phones not only to deliver messages," Snipes explains, "but also to receive health-related data from study subjects in their environment, and in real-time. We're the first to do this in this population." she adds.
The response has been gratifying: "Our farmworkers are using those phones, and they're using them daily. They're getting our messages and giving us back their data. And not just closed-ended data; they're giving us ideas. They are essentially part of our research team."
Results of the study are still preliminary, Snipes stresses. "But we're very excited about what we're seeing so far." Use of PPE has improved across the board, she says, and the approach itself has stirred interest among other researchers eager to learn more -- even from as far as South Africa. "They have similar exposure problems there and are really interested in using this methodology."
If it works, Snipes says, she would like to see the intervention scaled up to other, larger farmworker populations. Eventually, she hopes, it will inform public health policy across the U.S. and beyond. "That's what I want to accomplish before I die," she says.
For the moment she sits in her quiet office in University Park, but in a month or two she'll be back, quite literally, in the field.
"When I began this work I was very humbled to hear farmworkers say that they loved their jobs," she muses. "They love this work that is so tough and dangerous and doesn't pay much because, they say, 'Our hands feed the world.'
"I take that with me."
Shedra Amy Snipes is assistant professor of biobehavioral health, sas84@psu.edu. She was a fellow of the National Cancer Institute's Cancer Education Career Development program in 2010, and won the Kaiser Permanente Minority Leadership Development award for 2010-2012.