(Bloomberg) -- Florencio Gueta Vargas showed up for his usual shift at a hops farm in Toppenish, Washington on Thursday, July 29. The father of six would never make it home. 

It was a sweltering day with temperatures topping 100 degrees Fahrenheit (38 degrees Celsius) in the fields, where Gueta Vargas and others were tending to the plants used to make beer. His boss found him slumped over a tractor around 3 p.m. An hour later, he was pronounced dead of heart disease that was exacerbated by the heat.

Gueta Vargas isn’t alone. More extreme weather patterns are emerging due to climate change, and record-high temperatures sweeping over the western U.S. have led to fatalities for laborers who plant and harvest crops. While it’s difficult to track, the labor union United Farm Workers has identified three potential heat deaths in recent months.

The situation is likely worse outside the U.S., which is the world’s biggest agricultural exporter and has farms equipped with the most advanced technologies, like drones that can inspect fields. In developing nations like India, where 40% of the workforce is in farming, the cost of adapting to climate change with such tools can be prohibitive, according to Cicero Lima, an economist who has researched the effects of heat stress on farm labor and crop yields.

“If you have a lower capacity to adapt, you’re going to get hit twice, maybe three times more by climate change,” Lima said. “With lower crop yields, more people are making lower salaries and paying higher prices for food. In this scenario, the world will be more imbalanced.”

Read More: Climate Scientists Reach ‘Unequivocal’ Consensus on Human-Made Warming in Landmark Report

The heat deaths underscore the dangerous working conditions that pervade the world’s food supply chain, yet mostly go unnoticed. They burst into view last year in the U.S. when crowded meat processing plants became hot spots for Covid-19 outbreaks, forcing people to choose between keeping low-income jobs and putting their lives at risk. Hired farmworkers are just as vulnerable, if not more. Roughly half lack legal immigration status, and the labor-intensive jobs they do yield little pay and meager benefits. Most don’t have access to adequate health care. Many don’t speak English.

People laboring in the fields “are being used as a human shield to buffer the rest of the country against the most violent effects of climate change,” Elizabeth Strater, director of strategic campaigns at United Farm Workers, said in an interview. 

Heat Strokes

Gueta Vargas’ death is being investigated by Washington state’s labor department. Andy Gamache, an owner of the hops farm, said he was devastated, because the elderly worker had been an employee for decades. He had tried to save Gueta Vargas by performing CPR before medics arrived the day he collapsed. The company, Virgil Gamache Farms, allows workers take as many breaks as they need when it’s hot, and the pauses are compensated, Gamache said.

Gueta Vargas’ daughter, Lorena Gonzalez, blames the working conditions on the farm for his death. 

“No one deserves to pass away at work,” she wrote on a GoFundMe page to raise money for the funeral. “All my dad was trying to do was provide for his family.” 

A similar incident occurred June 26, when first responders arrived at a field in the town of St. Paul, Oregon, to try and revive a 38-year-old worker who had stopped breathing. Sebastian Francisco Perez had been on a crew moving irrigation lines. He later died, with heat listed as the preliminary cause. Oregon’s branch of the U.S. Occupational Safety and Health Administration is probing the death, a spokesperson said. The company, Ernst Nursery & Farms, declined to comment.

In late May, Adrian Aguirre, 34, died while traveling with other workers in a company van headed to Zirkle Fruit Co. in Selah, Washington, according to United Farm Workers. Organizers at the union said the van had no air conditioning and windows that didn't open, and think he likely died of complications due to heat. Before Aguirre died, he told his wife he was unbearably hot and felt ill, the union said. Zirkle didn’t respond to a request for comment.

At the federal level, there are currently no targeted OSHA rules covering heat stress, though it’s now looking into potentially creating a specific safety standard, according to a spokesperson. An Aug. 3 letter signed by several U.S. senators asked the agency to take action on regulations for excessive heat in the workplace. 

While both Oregon and Washington states have adopted emergency workplace rules, advocates say the measures don’t go far enough. Heat stress killed 815 U.S. workers while seriously injuring more than 70,000 between 1992 and 2017, according to government data, and farmworkers are 35 times more at risk of dying from heat than the general labor force. It’s also dangerous because the effects can come suddenly. Slight increases in temperature can significantly increase the risk of premature death from heat.

Employers “can’t expect the same level of productivity or they’re really putting the health of these workers in danger,” said Duke University climate change researcher Drew Shindell.

Strater said she fears fatalities and injuries will continue as extreme temperatures become  more common.

The term heat wave is misleading, because “a wave goes away,” she said. “What we’re really seeing is these increasingly severe weather conditions.”

Meanwhile, advocates say deaths and illnesses are likely undercounted and underreported, though some make it to OSHA. 

Last August, 53 workers at Polek Brothers Tobacco LLC in Connecticut were exposed to excessive heat, according to the agency. They harvested and handled tobacco for over 10 hours, including on days when the heat index approached 100 degrees Fahrenheit.

One employee was found unresponsive and taken to a hospital, where his core body temperature clocked in at 107.1 degrees Fahrenheit despite efforts to cool him down, according to OSHA. After several days in an intensive-care unit, he died. Mark Polek, a partner in the farm, declined to comment. The case is still open, meaning violations could be added or deleted.

Currently, there is little pressure to make farms safer. OSHA has a general welfare workplace safety requirement, but advocates say it’s often not enforced. Lawsuits are rare because the lack of federal industry standards and heat stress policies make them difficult to win, said Daniela Dwyer, managing attorney on the farmworker team for Texas RioGrande Legal Aid. Whole families often work on farms together, so if they sue, a company might not hire them back the next season. For those who do win, the compensation is often low because farm workers are paid so little in their lifetimes, she said.

Fruit Turmoil

Just as Covid-19 outbreaks last year led to turmoil in U.S. meat supply chains, the heat wave could expose similar vulnerabilities in those for fruits and vegetables. The virus outbreaks forced meat facilities to close or pare down crews, disruptions that led to temporary shortages of meat and runs on grocery stores.

There are signs the scorching temperatures are already affecting operations. It’s harder to work full shifts, so some farms have installed bright, sports-game-type lights so workers can pick crops at night or early in the morning. And there are fewer workers. In California, farmers are worried about fruit potentially rotting on trees because they’re short on labor by as much as 35%.

Still, many will continue to toil in the fields because they have few other options. Severa Cruz, a fieldworker in Florida, normally wears long-sleeve shirts, denim pants, boots and a wide-brimmed hat to shield herself from the sun. Although she was diagnosed with asthma three years ago, she’s kept her job to support her family. But she’s had to pull back on her productivity. She’s taking more breaks to stay out the sun, even though that means less money, since she’s paid by her rate of output.

“I have to just take a break because I feel like I’m suffocating,” she said.

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