Liza Gross and Peter Aldhous report:

For most of July 2019, stifling heat hung over the agricultural fields of California’s Central Valley, as farmworkers like William Salas Jiminez labored under the sun’s searing rays. Temperatures had dipped from 99 to 95 degrees Fahrenheit the last day of the month, when the 56-year-old Puerto Rico native was installing irrigation tubing in an almond orchard near Arvin, at the valley’s southern edge.

Around 1:30 that afternoon Salas sat down to rest. When he stood up to go back to work, he suddenly collapsed. An hour and a half later, he was dead. Reports filed with the U.S. Department of Occupational Health and Safety, or OSHA, say Salas died of a heart attack.

Salas’ death certificate lists atherosclerotic heart disease as the immediate cause of death. But it also lists “extreme heat exposure” and obesity as significant contributors. Both heart disease and obesity increase the risk of fatal heatstroke.

No federal standard protects workers from extreme heat, though OSHA proposed a rule in 2021—a half century after public health officials first recommended precautionary measures. California was the first of the five states that have passed a heat exposure standard and its requirements are considered among the toughest. Yet the standard doesn’t recognize an increasingly dangerous threat for agricultural laborers in a warming world: working in hot, polluted air.

According to the 2022 annual report from California OSHA, or Cal/OSHA, just two California farmworkers died from heat exposure between 2018 and 2022.

But an Inside Climate News review of federal farmworker death records, along with temperature and air pollution data, suggests the numbers may be much higher. Scores of farmworkers died in California between 2018 and 2022 when temperatures exceeded the threshold that triggers California’s heat safety requirements. All of these deaths occurred in counties with chronically unsafe air.

Eighty-three of the 168 farmworkers who died suddenly at work in California from 2018 to 2022 perished when temperatures exceeded 80 degrees Fahrenheit—when employers must provide adequate fresh water, shade and rest to cool down—within a day of their death. Thirty-six of these 83 workers died of heart attacks, strokes or other cardiovascular diseases; unspecified underlying medical conditions; or unknown or “natural causes.” Twelve died of respiratory conditions, including COVID-19, and one died of methamphetamine toxicity. The other 34 died from injuries sustained in accidents. Heat stress is known to increase the risk of death from cardiovascular and respiratory conditions, including COVID-19, drug use and workplace accidents. [Continue reading…]