When asked about climate change, President Trump often shifts the focus to America’s “clean air.”
“We have the cleanest air in the world in the United States and it’s gotten better since I’m president,” he said again this month while meeting with Prime Minister Leo Varadkar of Ireland.
America’s air is much cleaner than it used to be, but it’s still not “the cleanest.” And recent data suggests that air pollution is ticking back up.
Air pollution has improved dramatically over
the past four decades because of federal rules.
By one crucial metric, fine particulate pollution, the United States ranks 10th in air quality. New Zealand, Canada, Australia and several European countries can boast clearer skies.
This microscopic pollution – known as PM2.5 (because the airborne particles are less than 2.5 micrometers in diameter, or one-thirtieth the size of a human hair) – is a byproduct of burning and commonly comes from power plants, car exhaust and wildfires. It is particularly harmful to human health, causing asthma and respiratory inflammation and increasing the risk for lung cancer, heart attack and stroke.
But America’s air wasn’t always so clear. Particulate matter and other pollution have dramatically decreased over the past 40 years, in large part because of regulations put in place under the Clean Air Act of 1970 and its later updates, experts say.
That wide-ranging law gave the Environmental Protection Agency power to regulate pollution from stationary sources (like power plants, chemical factories and gas stations) and mobile ones (like cars, trucks and planes). It also established exposure limits for particulate matter and five other air pollutants hazardous to human health, which the E.P.A. is required to regularly review and update based on the latest science.
In 2009, the agency moved to regulate climate-warming greenhouse gases under the Clean Air Act.
Better air quality has saved lives, but millions
of Americans still breathe unhealthy air.
These pollution reductions have had big public health benefits.
Deaths related to air pollution fell by about 30 percent between 1990 and 2010, according to a recent study, primarily because of reductions in particulate pollution. Other research suggests that cleaner air has extended American life expectancy by several months and improved children’s health.
But, despite these gains, more than 110 million Americans still live in counties with unhealthy levels of pollution, according to the E.P.A. An estimated 100,000 Americans die prematurely each year of illnesses caused or exacerbated by polluted air.
“We’ve seen tremendous progress in reducing air pollution in the U.S.,” said Paul Billings, a representative of the American Lung Association, which advocates for air quality improvements.
“Cars and trucks are much cleaner than they were, power plants are cleaner, industrial operations are cleaner,” he said. “But cleaner air is not clean air.”
Many parts of the country, particularly Los Angeles and California’s Central Valley, continue to struggle with ground-level ozone, which forms when other pollutants react in the presence of sunlight and heat. This type of pollution, also known as smog, can damage the lungs and cause other serious health problems and death. (Please click the link below for the full story)
This article appeared on the The New York Times