Breathing the air in California can be a dangerous thing. The Golden State’s residents breathe the most polluted air in the country, according to the American Lung Association. When it comes to microscopic particle pollution, or “soot,” nowhere is more dangerous than California’s Central Valley, where four of the five most polluted cities in America are located.
See the 10 Most Soot Polluted Cities in America here.
California’s Central Valley is an enormous agricultural center in the middle of the state, home to more than four million people. Interstate highways “the 5,” “the 99,” and “the 80,” the state’s major north-south trucking corridors, run directly through the valley. As a result, tractor trailers and diesel engines are the area’s number one source of soot emissions in the summer time. In the winter, wood smoke is also a major contributor. Personal vehicles are also to blame: “One of the big things we’re dealing with is that we have a 1 to 2 ratio of people to vehicle miles traveled,” says Jaime Holt at the San Joaquin Valley Air Pollution Control District.
The problem in the valley is exacerbated by the area’s geography. Soot collects in the Central Valley basin, almost like water sitting at the bottom of a bowl, and is trapped there by an inversion layer of warm air that sits between the Sierra Nevada Mountains on one side, and the Coastal Ridge on the other.
When inhaled, soot particulates have known impacts on human health. Long-term exposure to soot has been definitively linked to heart disease, heart attacks, strokes, lung development problems, and asthma in children. There is even some evidence that fine particulate matter is a carcinogen and can cause birth defects. Even short-term exposure to particulates has been associated with premature death due to heart attack and stroke, and increased hospital visits for cardiovascular problems.
Soot Disproportionately Affects Latino Communities
Latinos in California are the most harmed by soot pollution. The American Lung Association reports numerous reasons why income and racial disparities exist when it comes to exposure to harmful pollution. Those include a lack of access to health care and more hazardous working conditions among these groups — in fact, Latinos are the least likely to be insured compared to all other ethnic groups in this country. Also, existing health conditions, such as diabetes, are exacerbated by soot pollution. Incidences of diabetes are higher among those living near major cities and within certain demographic groups, such as Mexican Americans, than in the population as a whole.
Let’s take a closer look at the demographics in five most soot-polluted cities in the country:
*Souce: America Lung Association and US Census Data
Latinos make up half of all people living in the most soot-polluted cities in the country, with populations in Visalia/Porterville reaching an overwhelming 60 percent.
EPA Soot Rules Will Save Lives
Help is on the way. This week, the Environmental Protection Agency (EPA) will hold hearings in the State capital of Sacramento on the National Ambient Air Quality Standards for Particle Pollution, also known as the Soot Rule. The agency has proposed an update to clean air standards on soot and other particle pollution that, according to Earth Justice, will annually prevent:
- 35,700 premature deaths;
- 2,350 heart attacks;
- 23,290 visits to the hospital and emergency room;
- 29,800 cases of acute bronchitis;
- 1.4 million cases of aggravated asthma; and
- 2.7 million days of missed work or school due to air pollution-caused ailments.
The EPA has published the proposed new standards in the Federal Register and will take public comments before signing a final rule by no later than December 14, 2012. Finalizing these rules will help keep all Americans safer and healthier. But in California’s Central Valley, it is often a matter of life and death.
Jorge Madrid is a research associate for the Energy Policy Team; Max Frankel is a senior at Vassar College.