Soot is a somewhat old-fashioned term for what scientists now call particulate matter—stuff that is so small, it can float around in the air. While particulate matter can be just about anything, from dirt to dust to marine spray, the tiniest leftovers from the burning of fossil fuels are the major culprit when it comes to human health. That’s why we still often refer to particulate matter as soot. If you’re imagining a Victorian chimney sweep, you’ve got the basic idea.
Speaking of the Victorian era, that’s where the Trump administration’s science advisors appear to be stuck. A mountain of studies in recent years has proven how dangerous particulate matter is to human health. We understand exactly how particulate matter kills. It enters your airways, causing or worsening a litany of respiratory ailments. The finest particles (less than 2.5 microns across) can enter your bloodstream, increasing the risk of heart attacks, strokes, and even cancer. Air pollution is now the fourth-leading risk factor for early death globally, and much of that comes down to particulate matter. Scientists have not identified any safe level of particulate matter. Basically, the less you inhale, the healthier you will be.
Under federal law, the U.S. Environmental Protection Agency is required to review particulate matter standards and recommend changes in accordance with developing science. The EPA’s own scientists had recommended lowering current limits, citing evidence that even a modest reduction could save more than 30,000 lives per year.
The Trump administration’s justification for rejecting the recommendation of its own scientists was typically nonsensical. “I got multiple recommendations,” said EPA administrator Andrew Wheeler. “Every scientist can take a look at this and reach a different conclusion.”
Except that public health experts across the country all reached the same conclusion: It’s past time to lower soot standards. Here’s a partial list of organizations that demanded tighter limits (take a deep breath if reading aloud): the Allergy & Asthma Network, Alliance of Nurses for Healthy Environments, American Heart Association, American Lung Association, American Public Health Association, American Thoracic Society, Association of Schools and Programs of Public Health, Asthma and Allergy Foundation of America, Children’s Environmental Health Network, Climate for Health, Health Care Without Harm, Medical Society Consortium on Climate and Health, National Association of County and City Health Officials, National Association of Pediatric Nurse Practitioners, National League for Nursing, National Medical Association, National WIC Association, Physicians for Social Responsibility, and Public Health Institute.
Wheeler’s comments are typical of the Trump administration’s approach to science: Ignore the facts, pretend there is no consensus, act confused, throw up your hands in melodramatic frustration, and just do whatever the fossil fuel industry wants.