In metropolitan areas across the continental United States, one in every three economically disadvantaged Latino immigrant neighborhoods is exposed to harmful, cancer-causing air pollution—emanating from refineries, factories, car exhaust, and more—a disturbing new academic study reveals.

was published online this week and is slated to run in the November issue of the journal Social Science Research.

Lead researcher Raoul Liévanos, an assistant professor of sociology at Washington State University, explained in a statement about the findings: “Neighborhoods comprised of nonwhite, economically disadvantaged people who do not speak English as a native language and are foreign-born are the most vulnerable to being near these toxic air emissions. This is particularly the case with Latino immigrants.”

Liévanos conducted his research by mapping areas that have the greatest exposure to toxic air pollution, finding that a majority of “hotspots” are in California and the northeastern United States. He then employed a “statistical analysis of the racial, socioeconomic and immigrant status of 2,000 neighborhoods and their proximity to toxic hotspots,” according to a summary of his research.