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Member Research & Reports

Member Research & Reports

Washington Researchers Find Heat Increases Risk for Outdoor Laborers

Warmer weather is related to an increase in traumatic injuries for outdoor agricultural workers in central and eastern Washington. These findings, which appeared October 7 in PLOS ONE, come from a study by researchers at the University of Washington School of Public Health and the Washington State Department of Labor & Industries Safety and Health Assessment and Research for Prevention (SHARP) Program.

[Photo: Dr. June Spector]

The study is the first to estimate the risk of traumatic injury in farmworkers using temperature data linked to the geographic location of the injury. Researchers reported on more than 12,200 traumatic injury workers’ compensation claims filed by agricultural workers from 2000 to 2012.

“Taken together with prior research in this area, our results suggest that we need to be proactive when it’s warm outside, particularly when work is physically demanding, in order to prevent heat-related injuries as well as heat-related illness,” said Dr. June Spector, lead author of the study and assistant professor in the School’s department of environmental and occupational health sciences.

Internal body heat generated from physical exertion contributes to overall heat stress. One of the most well-documented health effects of hot weather is heat-related illness. This can range from heat rash to heat stroke, which can be fatal.

“This study reinforces the importance of prevention,” said study co-author Dr. David Bonauto, a clinical associate professor also in the School’s department of environmental and occupational health sciences and research director of SHARP. “Employers need to provide plenty of fresh drinking water, start work as early in the day as possible, and encourage workers to take breaks and pace themselves.”

In the study, researchers identified the temperature and humidity at the approximate location of the injury on the injury day. The average daily maximum temperature between May and September during the twelve-year period studied was 82.2 degrees Fahrenheit, with temperatures at times exceeding 100 degrees Fahrenheit. To understand how heat may have been a factor in the injury, the researchers compared the heat and humidity on the injury day with days when there was no new injury for that individual working at the same work location.

Financial support for the study was provided by the National Institute for Occupational Safety and Health. Additional authors include Dr. Lianne Sheppard, Dr. Richard Fenske, Dr. Tania Busch-Isaksen, Ms. Miriam Calkins, Dr. Max Lieblich, and Mr. Darrin Adams.