Today, the U.S. Environmental Protection Agency (EPA) is announcing a proposal to strengthen a key national ambient air quality standard (NAAQS) for fine particle pollution, also known as PM2.5, to better protect communities, including those most overburdened by pollution. Fine particles, sometimes called soot, can penetrate deep into the lungs and can result in serious health effects that include asthma attacks, heart attacks and premature death – disproportionately affecting vulnerable populations including children, older adults, those with heart or lung conditions, as well as communities of color and low-income communities throughout the United States. (Source: EPA)