More days per year are dangerously hot – and that number is growing. Protecting farm labor from heat stress should be a priority.

by Enrico Villamaino

A new study released by the University of Washington and Stanford University reveals how climate change can negatively affect the ability of agricultural workers to safely operate in the field.

Dr. Michelle Tigchelaar, a researcher at Stanford, decided to focus her study on this topic after she learned of the death of a worker in the field. “In the summer of 2017, I read about the death of a man picking blueberries due to complications from heat stroke during an especially hot and smoky period,” Tigchelarr explained. “I realized while there has been a great deal of research regarding climate change and agriculture, the focus was normally on crop yield projections. There hasn’t been much focus on how climate change impacts the health of farm laborers picking fruits and vegetables. That’s what started this two-year study.”

Tigchelaar believes that the rise in global temperatures endangers both the productivity and the lives of field workers. The number of agricultural workers in the U.S. is estimated to be more than two million. “The risk is rising sharply. If nothing is done to address this, the hazards to field workers from exposure to these increasingly hot seasons will double in 30 years … and triple by the end of the century,” she said.

The average ag worker currently experiences an average of 21 days each year when the daily heat index, a mix of air temperature and humidity, exceeds workplace safety standards. Tigchelaar’s study predicts the number of unsafe days will jump to 39 days per season by 2050, and to 62 by 2100.

In determining what were considered “safe” and “unsafe” working conditions, Tigchelaar relied upon heat warning standards used by OSHA and the National Weather Service.

The effects of rising temperatures will not be felt uniformly across all regions. Tigchelaar is particularly worried about the American South. “If this trend continues, eventually the entire summer growing season will be unsafe in the South,” she stated.

There are additional factors compounding the dangers to ag workers. “This is a population that is already more vulnerable to health risks,” Tigchelaar said. “Agricultural workers tend to have poorer access to health coverage, a majority say they are not fluent in English and many do not have legal work status in the U.S., so they are less likely to seek medical care.”

Tigchelaar noted that farmworkers already report a higher than average number of kidney ailments and other conditions related to heat stress.

The study also looked at different strategies the farming industry could adopt to protect worker health. The four-pronged approach recommended in the study includes working at a less vigorous pace, taking longer breaks, wearing thinner and more breathable protective clothing and taking breaks in a cooled shelter.

“The most effective way to reduce heat stress would be to develop lighter protective clothing,” Tigchelaar said, adding, “That would still shield workers from pesticides or other hazards. And using any three of these four adaptation strategies in combination would be enough to offset the temperature increases.”

She noted that there needs to be more regulation, at both the state and federal level, to ensure safer working conditions. California and Washington both have standards in place to limit workers’ heat exposure, but according to Tigchelaar, even these fall short of what her study recommends.

Tigchelaar said this issue cannot be effectively addressed outside of the larger context of climate change. “The best way to help these workers is to confront the underlying problem itself. There are larger structural issues to consider. In order to save farm productivity, we need to limit climate change as well as simply helping these workers adapt to it.”