and its negative health effects on children

Masaya Kato, Ph.D., MPH, Elyanne Ratcliffe,MD and Wendy Hobson-Rohrer, MD.Doctors for Global Health.

Agricultural chemicals are used heavily in farming to control pests. While all pesticides can harm humans, insecticides and herbicides cause most human poisoning. Pesticides affect humans through three mechanisms of entry: ingestion, inhalation and dermal absorption. In under-developed countries, the least expensive pesticides are utilized due the inability of farmers to purchase more expensive, safer products. As a by product of pesticide use, farmers and their families are affected daily with health problems directly resulting from pesticide exposure. Doctors for Global Health, in partnership with a rural Salvadoran community, conducted a study of pesticide use and practices to determine not only the negative health impacts of pesticide exposure, but also to work alongside the community to create positive, lasting interventions in the community.

Pesticides pose an even higher risk to children than to adults. Due to a combination of play behavior in fields, take home residues from family members, residence in proximity to farmland and even by direct agricultural work, children may be subject to substantial long-term pesticide exposure. Furthermore, compared to adults, children have enhanced susceptibility to toxic chemicals because of differences in size, metabolism and growth (Cooper, 2001). Children have greater surface area to body weight ratio, leading to higher amounts of pesticides being absorbed through skin. Children also have higher circulatory flow rates that impact the distribution of toxins in the body. Important liver enzyme activity varies with age, causing the same amount of chemical exposure in an adult to have a greater impact in a child. Furthermore, a child's developing immune system may be less effective in clearing hazardous agents (Mills and Zahm, 2001). Children are most commonly exposed to pesticides through diet, drinking water and residential use. However, children in agricultural communities may be at increased risk. A study in rural El Salvador, suggested that members of farmers' families, including children, experience adverse health effects through environmental pesticide exposure, even if they do not perform field work (Azaroff and Neas 1999). In another study, chemical residues were found in the soil, on work boots, steering wheels and children's hands, all likely tracked into the home by farm working family members (Lu, 2000).

Pesticide exposure is compounded if the distinction between farmland and residence is blurred, such as when a house is situated within or on the boundary of farmland and when children use agricultural fields as play areas. In focus groups of migrant farm working families in Texas, children reported high exposure activities such as playing in dirt near fields, swimming in irrigation channels, being outside close to fields during spraying, and eating fruits and vegetables without washing.(Cooper, 2001). Even more concerning, an estimated 25% of all farm labor in the United States is performed by children as young as 10 years of age (Rohlman, 2001). These children are directly exposed to pesticide toxins. Exposure to agricultural chemicals can start as early as prenatal life (Cooper, 2001) and continue into infancy, with studies documenting organochlorine  residues in mother's milk in areas of high agricultural activity (Stuetz, 2001; Campoy, 2001). Unfortunately, little is known about the extent or magnitude of health problems related to occupational pesticide exposure in children. Pesticides are known to be toxic to the developing central nervous system and their effect on neurobehavioral function has only begun to be studied (Rohlman, 2001). Parental occupation in farming has also been linked to childhood cancers such as leukemia (Reynolds, 2002) and Ewing's sarcoma (Valery, 2002) and may also affect the developing endocrine system (Rogan and Ragan, 2003). 

Risk

Agricultural use of pesticides has significant effects on children, both in developed and developing countries. Children can be exposed to pesticides through multiple pathways and routes and may be at higher risk of toxic effects than adults. Therefore, it is critical to raise awareness and to accompany communities in making efforts to decrease childhood exposure to agricultural chemicals. Participatory research in rural El Salvador Doctors for Global Health (DGH) is a private, not-for-profit organization promoting health, education, art and other human rights throughout the world. The mission of DGH is "To improve health and foster other human rights with those most in need by accompanying communities, while educating and inspiring others to action." DGH's approach is to accompany communities with small, community-oriented health initiatives that also promote human rights, encourage sus- Agricultural pesticide exposure and its negative health effects on children Article atainability, and respect environmental concerns. The use of agricultur all pesticides and their negative effect on children's health was noted by a DGH partner organization in El Salvador.

Santa Marta is a mountainous community in rural El Salvador, where most people rely on subsistence agriculture, cultivating corn, beans and sorghum. As common in many agricultural communities in the world, farmers use pesticides. For physical therapist Brenda Hubbard and physician Juan Manuel Canales, both who worked in the community for many years, the health impact of pesticides among the villagers had been a major concern. In their clinic, they had observed high numbers of miscarriages, congenital anolomies and cancers. In 2001, DGH started collaboration with the clinic and the community to address this problem.

DGH members Masaya Kato and Denise Zwahlen used participatory research to conduct an assessment of pesticides in Santa Marta. The project's objectives were not merely to appraise pesticide use and its impact, but also to raise communities' awareness of pesticide-related health risks and to provide information to help communities to make decisions on future actions. Thus, eight local students (age 15-20, 4 females, 4 males) were recruited as original study team members and worked with DGH researchers in all the aspects of the study. Later, Max Fisher, another DGH volunteer, used a similar approach to further explore the impact of pesticide exposure in pregnant women on birth outcomes and later children's development.

Survey

In the first study, DGH researchers and student members discussed community pesticide problems and developed a shared consensus. Students' observation on current pesticide use served as basis to develop a draft questionnaire, which was reviewed by local agronomists and pilot-tested by the study team. After receiving training on interview skills and ethics, the student members visited and interviewed 87 primary farmers at systematically sampled households. Data was analyzed and based on the results, recommendations were developed. The students then presented the results and recommendations to their own communities at a workshop.

Research confirmed health risks of pesticide use. The survey results demonstrated that agricultural pesticide use posed a significant health risk among villagers. First, pesticides widely used in the communities are highly toxic. Methyl parathion, used by 60% of surveyed farmers, is an organophosphate insecticide classified by World Health Organization as an extremely hazardous pesticide (WHO 2000) and is banned by a number of countries world-wide. Furthermore, as high as 97% responded they use paraquat. Paraquat, an herbicide, also banned or restricted in many countries due to acute toxicity and the absence of an antidote, is especially popular in developing countries, as it is labor-saving and cheap.

The survey confirmed students' initial observation: unsafe pesticide use practices are very prevalent. Very few farmers use personal protective equipment. Only 1-2% regularly used gloves, glasses and filtered masks. A high proportion of farmers reported risk behaviors such as eating food while using pesticides, spraying pesticides into the wind and not bathing after using pesticides These same farmers will bring home pesticides on their clothes and therefore expose their families.

Exposure

Not only the adult farmers, but also children are at the risk of direct pesticide exposure. The data showed that a high proportion of male children is engaged in farming work (Figure 1). Children spray extremely hazardous pesticides without protective equipment, often in barefeet. Farmers also reported that their children had experienced various health effects after using pesticides, such as headaches, dizziness, vomiting and nose bleeds.

Furthermore, environmental (non-occupational) exposure of farmers' family members to pesticides is very likely, suggesting another threat to children's health and sound development. 41% farmers discard contaminated water in a creek or near a well. Many store pesticides in the bedroom or kitchen, use pesticide containers to store drinking water, and wash pesticide-contaminated clothes together with other family clothes.

These findings confirmed Brenda's observations of children and pregnant women applying pesticides. For years, mothers brought their teenage children suffering from pesticide poisoning to the clinic. Brenda questions whether there is a link between community pesticide use and significant medical problems like congenital malformations and uterine cancers, although no direct evidence exists to answer her question.

“Understanding root causes, devising a communitybased solution.”

A number of root causes underlie the pesticide problem in El Salvador, as well as in other developing countries. Highly hazardous pesticides are not regulated and enforcement is weak even if regulation exists. Multinational corporations have the power and influence to promote the heavy use of pesticides and to set pesticide policy. Globalization and free trade imperatives that are dominating today's world economy will only serve to worsen this situation. Subsistence farmers will have even less ability to have their voices and concerns be heard against the power of large multinational corporations. Those who suffer the most have the least power.

Poverty affects the pesticide problem in a variety of ways. Protective equipment is neither available nor affordable to farmers in poor countries, and moreover it is not practical to wear in tropical climates due to high heat and humidity. An illiterate farmer is unable to read the directions about proper pesticide use. A farmers' financial situation does not allow them to purchase the adequate spraying equipment or safer, but more expensive, pesticides. If farmers could afford salaries for field hands, they would not have to involve their children in spraying work. Understanding such causes, it is not surprising to vlearn that an estimated 99% of case fatalities of pesticide poisoning occur in developing countries (Jeyaratnam 1992).

Is there a solution for this challenging problem? The promotion of the "safe-use" procedure, particularly training on appropriate use practices, has been viewed as a principal measure to protect farmers in the developing world from pesticide exposure. However, Wesseling states "there is no strong evidence to support the effectiveness of such procedures….it actually promotes and increases the use of pesticides without controlling the adverse effects as claimed." (Wesseling 1997) Many researchers, action groups and international agencies started to emphasize the need for development and application of alternative pest control methods. At the same time, especially in Central American countries, topdown effort to introduce integrated pest management technique has not been successful (Murray1994). Murray argues, it is crucial to use "more participatory, farmer-first and agro-ecology approaches" to introduce an alternative to chemical-intensive farming.

The DGH participatory pesticide project was aneffort to involve the community in addressing the pesticide issue. After the research was conducted and the results and recommendations were presented, DGH supported a group of farmers interested in forming a committee to address the pesticide issue. The group piloted the use of alternative agricultural methods to cultivate a small demonstration plot. The outcome was mixed and both financial and technical support were difficult to garner. But, the participants' motivation and commitment to pursue alternative methods were reinforced.

Only by involving the local community and empowering them to take action on the recommendations that they created can real change occur. By decreasing pesticide exposure, the community of Santa Marta will live in a healthier environment and fulfill part of the children's human right to grow up healthy. 

Doctors for Global Health

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