A coroner in Britain recently became the first to acknowledge a hard but obvious truth — air pollution is deadly.

The official ruled that the 2013 fatal asthma attack of a 9-year-old girl was made possible by the nitrogen dioxide and fine particulate matter she was exposed to over time, mostly from the emissions of vehicles passing by her home near a major road in southeast London.

In Britain, the first-of-its-kind ruling could pave the way for lawsuits by those harmed by pollution. Here in the United States, it should at the very least raise awareness of a problem that is, to our peril, often underestimated.

Fine-particle air pollution, or soot, is largely the result of industrial operations, power plant emissions, smokestacks and vehicle exhaust. It is so small it can enter the lungs and the bloodstream, and it has been linked to heart and respiratory disease, stroke, lung cancer, even dementia and Alzheimer’s disease. It has also been shown to have an impact on learning in children, even causing developmental delays.

Most recently, research has found an association between exposure to air pollution and mortality from COVID-19.

In the United States, air quality improved steadily for years, with pollution reaching a two-decade low in 2016.

However, air pollution worsened in 2017 and 2018, leading to thousands of additional deaths. Though still better than decades ago, air pollution is estimated to contribute to 70,000 deaths a year, more than fatal shootings and car accidents combined.

We are not immune here. Because of its high rate of asthma and other respiratory ailments, Maine has a lot of residents who are vulnerable to worsening air quality.

Experts say the rise in pollution can be attributed to lax enforcement of the Clean Air Act, something that started under the Obama administration and became more lax under President Trump.

Just this month, the Trump administration rejected tougher standards on air pollution, even though its own scientists had called for them and noted they would save thousands of lives.

Most of the lives affected by pollution are those who create the least of it: poor and minority Americans, who also often have other health issues, and whose homes are most often near major polluters such as highways, industrial sites and power plants.

That makes pollution not only an environmental issue, but a matter of justice as well. We shouldn’t allow harmful levels of particulate into the air, and we certainly shouldn’t force the most vulnerable Americans to bear its harmful effects.

Air pollution is deadly. The coroner in Britain recognized that fact, and the rest of us should too.