Air pollution

Most of the daily air pollution studies on health have focused on statistical significance to establish the existence of the phenomenon, which has already been shown by the Great London Fog of 1952, during which black smoke levels increased about 10-fold, and thousands died over several days. The scientific community would be better served by addressing epidemiological and physiological questions.
In our somewhat academic household, “solving differential equations” was a euphemism for tackling a challenging intellectual problem with an uncertain outcome.  Pinning down the health effects of air pollution exposure is one such problem.
Climate change has now largely supplanted COVID as the main source of hand-wringing and angst in the popular press. Carbon is directly involved in climate change through carbon dioxide (CO2) and airborne elemental carbon particles (EC). COVID-19 has an indirect impact as well. Here I add some details to the fray to insert some clarity and reason.
Epidemiological studies have reported statistically significant relationships between long-term air pollution and mortality over the past 50 years, frequently without controlling for smoking. Smoking is perhaps the strongest actionable risk factor in our longevity, and despite dramatic declines, it remains so in modern society. Smoking more than one pack per day can double the risk of all-cause mortality and increase lung cancer risk at least 10-fold.
Why are catalytic converters becoming an endangered species? Because they contain three valuable metals - platinum, palladium, and rhodium - making them worth hundreds, even thousands of dollars, stolen or not. It's the rhodium thieves are after. It's very rare, very expensive and has some strange properties. Could there be a better time for a Dreaded Chemistry Lesson from Hell? I think not.
The World Health Organization (WHO) adopted a dose-response function for PM2.5 that lumps outdoor ambient air quality, second-hand (passive) smoking, and indoor household air pollution. It has been used in 80 published studies of the “Global Burden of Health” (GBD). Here I take a closer look and incorporate some additional risk estimates.
The New York Times reported that the US Environmental Protection Agency (EPA) will reconsider reducing the National Ambient Air Quality Standard (NAAQS) from its current 12 μg/m3 as an annual average. What’s new, and what’s a tired retread? 
The first general alarm about the lethal effects of community air pollution was sounded in London in December 1952 during a severe fog episode that shut the city down and flooded hospitals and morgues. Subsequent media discussions about the benefits of cleaner air often cite the World Health Organization's global estimate of 7 million air pollution-related deaths annually (about 12% of the total), primarily based on studies of long-term mortality differences among US cities during previous decades. More recent publications have focused on short-term temporal associations. So how do long- and short-term analyses relate?
Dear Director-Designee Regan: What an opportunity you now have to move the EPA's goals and objectives into the 21st century!
There are any number of papers supporting the idea that higher levels of air pollution are inversely correlated with poorer health outcomes. These studies all suffer from the fellow travelers of air pollution, traffic density, poverty, and lesser education which confound a clear linkage between air pollution and health. A new study offers a possibility.
Maybe barbeque and beach trips were modified over the weekend in the face of COVID-19. But surely it's appropriate to have a time-tested cautionary article go with America's birthday.
The more recent cases of COVID-19 seem to be coming from homes and family contacts, rather than from strangers. And there, with the "opening up" of social mobility, is an increasing interest in the spread and dispersion of airborne COVID-19 particles. There are lessons to be learned from atmospheric science, especially when it pertains to the dispersion of small particles.