Daily News Archive
From July 27 2005

New Study Finds Pesticide Poisoning at Nation’s Schools
(Beyond Pesticides, July 27, 2005)
A new study published in the Journal of the American Medical Association today finds that students and school employees are being poisoned by pesticide use at schools and from drift off of neighboring farmlands. The study, “Acute Illnesses Associated With Pesticide Exposure at Schools” (Vol. 294, No. 4, pp455-465), by Walter A. Alarcon, M.D. (National Institute for Occupational Safety and Health) et al, analyzed 2593 poisonings from 1998 to 2002 from three surveillance systems. While the analysis finds incident rates overall of 7.4 cases per million children and 27.3 cases per million employees, the authors conclude, “[T]hese results should be considered low estimates of the magnitude of the problem because many cases of pesticide poisoning are likely not reported to surveillance systems or poisoning control centers.” The authors recommend that strategies be adopted to reduce the use of pesticides at school and reduce drift.

The authors of the study work for a range of federal and state agencies, including theNational Institute for Occupational Safety and Health, U.S. Centers for Disease Control and Prevention; Office of Pesticide Programs, U.S. Environmental Protection Agency; and state health and environmental agencies in California, Florida, Louisiana, Michigan, New York, Oregon, Texas, and Washington. The surveillance data comes from three sources: California Department of Pesticide Regulation (CDPR) and the Sentinel Event Notification System for Occupational Risks (SENSOR), and Toxic Exposure Surveillance System (TESS).

The study finds that the incidence rates among children increased significantly from 1998 to 2002. Illness of high severity is found in three cases, moderate severity in 275 cases, and low severity in 2315 cases. Most illness is associated with insecticides (35%), disinfectants (32%), repellents (13%), and herbicides (11%). Among 406 cases with detailed information on the source of pesticide exposure, 281 (69%) are associated with pesticides used at schools and 125 (31%) are associated with pesticide drift exposure from farmland.

The authors cite that the study misses incidents for which medical attention is not sought or reported to a surveillance system or a poison control center. “Even when individuals seek medical care, their illness may not be recognized as pesticide-related, because of the nonpathogomonic nature of the signs and symptoms and because clinicians receive little training on these illnesses.”

Overall, insecticides are associated with 895 illnesses and most often involve the following: pyrethrins (13%), chlorpyrifos (13%), malathion (9%), and pyrethroids (5%); Disinfectants are associated with 830 cases and most often involve the following: sodium hypochlorite (21%), phenol compounds (21%), pine oil (13%), and quaternary ammonium compounds (10%). Repellents are associated with 335 illnesses and most often involve the following: naphthalene (41%), and diethyl toluamide (DEET) (19%). Herbicides are associated with 279 illnesses and most often involve: glyphosate (36%), 2,4-D (19%), and pendimethalin (14%).

The analysis can be further refined by looking at specific surveillance data sources. For example, when combining the data from the CDPR and SENSOR, which predominantly report incidents involving adults, the most common active ingredients associated with poisonings from school pesticide use include diazinon (insecticide, 23%), sodium hypochlorite (disinfectant, 17%), chlorpyrifos (now withdraw for use by schools, 14%), quaternary ammonium compound (disinfectant, 14%), and malathion (insecticide, 5%). The most common active ingredients associated with poisoning from pesticide drift include insecticides, fungicides and herbicides: chlorpyrifos (22%), methamidophos combined with chlorothalonil and propargite (20%), mancozeb combined with glyphosate (16%), cyfluthrin combined with dicofol (13%), and malathion (10%).

While the study looks at acute, or short-term, effects, the study authors note that, “Repeated pesticide applications on school grounds raise concerns about persistent low level exposures to pesticides at schools.” Continuing, the authors state, “The chronic long-term impacts of pesticide exposures have not been comprehensively evaluated; therefore, the potential for chronic health effects from pesticide exposures at schools should not be dismissed. Unfortunately, the surveillance methods used in our report are inadequate for assessing chronic effects.” In addition, the authors note that pesticides on school grounds can be tracked inside school buildings.

The authors note the lack of protection for school children and employees under federal law. Citing Beyond Pesticides studies, The Schooling of State Pesticide Laws and Are Schools Making the Grade?, the authors point out that state laws provide some protection but are varied, leaving large gaps.

TAKE ACTION: Join the School Pesticide Reform Coalition, sign on to the School Pesticide Reform Protocol, and ask your U.S. Representatives and U.S. Senators to support the School Environmental Protection Act. For more information, contact Michele Roberts at Beyond Pesticides, 202-543-5450. The corresponding author of the report can be contacted: Walter A. Alarcon, MD, National Institute for Occupational Safety and Health, 4676 Columbia Pkway, Mail Stop R-17, Cincinnatie, OH 45226.