What killed these three vineyard workers in California’s Central Valley?

United Farm Workers—America’s largest farm workers union—is reporting that the three farm workers who died last week on three separate vineyards in California were suffering from undue heat exposure. All of the deaths took place in Kern County in California’s fertile Central Valley. However, the Kern County coroner’s office is disputing that heat was a factor in at least one of the women’s deaths, who fell ill after working in the hot sun.