To Kill Climate Rule, EPA Wants to Redefine Danger of Soot
by Niina Heikkinen (E&E News) Whether it’s in haze-shrouded cities, plumes of car exhaust or even clear skies, fine particle pollution can be found just about everywhere in the United States.
… Exposure to fine particles is linked to premature death and higher risks of asthma and heart attacks.
After decades of increasingly strong assertions that there is no known safe level of fine particle exposure for the American public, EPA under the Trump administration is now considering taking a new position. The agency is floating the idea of changing its rulemaking process and setting a threshold level of fine particles that it would consider safe.
The change would affect how EPA counts the health benefits of reducing fine particles when crafting rules aimed at reducing other pollutants, like greenhouse gases.
Fine particles, or particulate matter, get their shorthand name, PM 2.5, from their size. Measuring in at a minuscule 2.5 micrometers, these particles are a tiny fraction of the width of a human hair.
They can come from sources like power plants and automobiles, and from smaller sources like fireplaces and cigarette smoke. Fine particles can also form from other pollution sources in the atmosphere through a chemical reaction. They’re everywhere.
Because of their ability to travel deep into the lungs, a number of its effects are linked to the cardiovascular system. The pollutants have been found to enter the bloodstream. READ MORE