Air pollution has been linked to numerous diseases including asthma, cancer, and heart disease, but while air pollution can negatively affect all of us, its damage is disproportionately felt by certain populations. Breaking down where air pollution is most potent and why is the first step to ensuring everyone has access to healthy, clean air, and a new tool from ProPublica is the first to ever offer a fully comprehensive map of cancer-causing US industrial air emissions down to the neighborhood level.
The new map is the product of two years of analysis using primarily data from the Environmental Protection Agency (EPA) model called Risk-Screening Environmental Indicators (RSEI). This model takes into account emissions, weather, and industrial facility location data to estimate concentrations of toxic chemicals in neighborhoods surrounding these facilities.
What sets the ProPublica map apart from the EPA’s tool is that the EPA does not consider the cumulative cancer risk of multiple exposure sites. While they may deem an area “safe,” they don’t take into account the aggregate health effects on someone who lives in the vicinity of multiple industrial sites.
The map is largely based on six “criteria pollutants” found to have carcinogenic effects. These are carbon monoxide, lead, ground-level ozone, particulate matter, nitrogen dioxide, and sulfur dioxide. Although there is a myriad of cancer-causing pollutants we encounter every day, this map focuses just on those from stationary industrial sites, emphasizing the risk specifically on those who live in their vicinity. It does not, for example, take into account pesticides, wildfires, car exhaust, or Superfund sites.
RSEI splits up the US into grid cells which measure 810 meters wide. The ProPublica researchers culled through seven billion rows of RSEI data and identified the nation-wide presence of 105 pollutants. They then took these pollutants and assessed them based on inhalation unit risk, or the measure of inhalation risk for someone living within a certain radius of the emission source.
When completing these calculations, the team was left with a map of the entire US with identified hot spots where cancer risk is at or above 1 in 100,000. Some of the identified hot spots come as no surprise, like the region of Louisiana referred to as “cancer alley.” Others include Port Lavaca, Texas, where a population of 76,000 has an average cancer risk rate of 1 in 29,000. Those who live closest to the industrial facilities in the neighborhood have a cancer risk of 1 in 63.
Unsurprisingly, many of the hot spots identified by the map are neighborhoods with predominantly low-income residents or residents of color. This map is not only the most comprehensive of its type, but also demonstrates in incredible detail the air pollution consequences of industrial facilities. Hopefully, this map can be used by governments, NGOs, and residents to advocate for stronger emissions regulations like those mandated by the Bay Area Air Quality Management District in California.
We encourage you to learn more and explore the map here.
