Acute Pesticide Illnesses Associated with Off-Target Pesticide Drift from Agricultural Applications: 11 States, 1998-2006

Article excerpt

BACKGROUND: Pesticides are widely used in agriculture, and off-target pesticide drift exposes workers and the public to harmful chemicals.

OBJECTIVE: We estimated the incidence of acute illnesses from pesticide drift from outdoor agricultural applications and characterized drift exposure and illnesses.

METHODS: Data were obtained from the National Institute for Occupational Safety and Health's Sentinel Event Notification System for Occupational Risks--Pesticides program and the California Department of Pesticide Regulation. Drift included off-target movement of pesticide spray, volatiles, and contaminated dust. Acute illness cases were characterized by demographics, pesticide and application variables, health effects, and contributing factors.

RESULTS: From 1998 through 2006, we identified 2,945 cases associated with agricultural pesticide drift from 11 states. Our findings indicate that 47% were exposed at work, 92% experienced low-severity illness, and 14% were children (< 15 years). The annual incidence ranged from 1.39 to 5.32 per million persons over the 9-year period. The overall incidence (in million person-years) was 114.3 for agricultural workers, 0.79 for other workers, 1.56 for nonoccupational cases, and 42.2 for residents in five agriculture-intensive counties in California. Soil applications with fumigants were responsible for the largest percentage (45%) of cases. Aerial applications accounted for 24% of cases. Common factors contributing to drift cases included weather conditions, improper seal of the fumigation site, and applicator carelessness near nontarget areas.

CONCLUSIONS: Agricultural workers and residents in agricultural regions had the highest rate of pesticide poisoning from drift exposure, and soil fumigations were a major hazard, causing large drift incidents. Our findings highlight areas where interventions to reduce off-target drift could be focused.

KEY WORDS: agriculture, drift, pesticides, poisoning, surveillance. Environ Health Perspect 119:1162-1169 (2011). doi:10.1289/ehp. 1002843 [Online 6 June 2011]

Pesticide drift, which is the off-target movement of pesticides, is recognized as a major cause of pesticide exposure affecting people as well as wildlife and the environment. In the United States in 2004, > 1,700 investigations were conducted in 40 states because of drift complaints, and 71% of the incident investigations confirmed that drift arose from pesticide applications to agricultural crops (Association of American Pesticide Control Officials 2005). Pesticide drift has been reported to account for 37-68% of pesticide illnesses among U.S. agricultural workers [California Department of Pesticide Regulation (CDPR) 2008; Calvert et al. 2008]. Community residents, particularly in agricultural areas, are also at risk of exposure to pesticide drift from nearby fields. Agricultural pesticides are often detected in rural homes (Harnly et al. 2009; Quandt et al. 2004). Alarcon et al. (2005) reported that 31% of acute pesticide illnesses that occurred at U.S. schools were attributed to drift exposure.

The occurrence and extent of pesticide drift are affected by many factors, such as the nature of the pesticide (e.g., fumigants are highly volatile, which increases their propensity for off-site movement [U.S. Environmental Protection Agency (U.S. EPA) 2010], equipment and application techniques (e.g., size and height of the spray nozzles), the amount of pesticides applied, weather (e.g., wind speed, temperature inversion), and operator care (Hofman and Solseng 2001). Pesticide applicators are required to use necessary preventive measures and to comply with label requirements to minimize pesticide drift. Pesticide regulations such as the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and EPA's Worker Protection Standard require safety measures for minimizing the risk of pesticide exposure (U.S. EPA 2008, 2009), and many states have additional regulations for drift mitigation (Feitshans 1999). …