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Member Research & Reports

Member Research & Reports

Washington Study Examines Heat-Related Illnesses in Agriculture, Forestry Jobs

Heat-related illnesses in agricultural and forestry workers in Washington state are an important public health problem and likely under-recognized and under-reported, according to a new study by the University of Washington School of Public Health.

June Spector

[Photo: Dr. June Spector]

Researchers examined workers’ compensation claims in Washington from 1995 to 2009 and found 84 cases where agricultural and forestry workers filed claims for heat-related illness. Such illnesses range from minor heat rash and cramps to fainting and severe heat stroke. Fifteen percent of the Washington claims were characterized by heat stroke or acute renal failure; one person died. Several claims involved accidents, such as falling from heights when workers felt hot, sweaty, and dizzy. The mean heat index on the days when the claims occurred was 99 degrees F.

“Even people who seem otherwise healthy can be at high risk of heat-related illnesses if they are doing a lot of physical activity and have to exert themselves,” said lead author Dr. June Spector, assistant professor of environmental and occupational health sciences. “Many agricultural workers are migrant workers, aren’t English-speaking and may not have the resources to protect themselves from hazards like heat outdoors.”

Potential risk factors included lack of shade, heavy physical activity, wearing certain kinds of protective equipment, getting paid piece-rate, and long distance to drinking water or inadequate water supplies, the study noted.

The study was published in the American Journal of Industrial Medicine and was done in collaboration with the Washington State Department of Labor and Industries’ Safety & Health Assessment & Research for Prevention (SHARP) program. Researchers also examined violations of state rules designed to protect workers from heat-related illnesses. They found 60 citations of 28 businesses for violating Washington’s Heat Rule, which took effect in 2008 and requires employers to train employees on heat-related illness and provide at least a quart of drinking water per hour.

Researchers noted an increase in the frequency of claims over time, but also a decline in the number of severe cases since 2005, the last time a heat-related fatality occurred. Climate change threatens to increase the risk of heat-related illness in outdoor workers over time, the researchers noted.

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