A new report by a climate NGO says that air pollution has increased in the US for the first time in 8 years primarily due to wildfires offsetting gains in reductions in human caused pollution achieved by the Clean Air Act. Vast swaths of the continental US will have unhealthy air by 2054. Now one in four Americans are exposed to unhealthy air and that is expected to grow by 50% in the next few decades.
An example of what is occurring is the Canadian wildfires of June 2023 that turned the skies of northeastern America orange and caused exposure to the worst day of polluted air since 2006. The smoke carried tiny particulate matter called PM2.5 (microns) that can lodge deep inside a person's lungs and cross the brain-blood barrier. Prolonged exposure can cause Parkinson's Disease and dementia, as well as respiratory illness. There is no safe exposure level to PM 2.5. Although wildfire smoke is not counted against air quality goals by the EPA, wildfire smoke accounts for a third of all particulate matter pollution.
The number and intensity of wildfires are expected to increase as the planet warms up and vegetation drys out. Disadvantaged populations in urban centers will be affected most since they do not have the means to ameliorate the effects of air pollution by moving or filtering in-door air. Black children are five times more likely to suffer asthma than white children. Outdoor workers will also be affected more.