Exposure to coal power plant emissions may be twice as dangerous than previously thought, study finds

One can only imagine the excitement that coursed through humanity once we collectively realised what we could do with coal. This material almost single-handedly powered our industrial revolution, liberating us to pursue technology and exploration with unmatched vigour. All was going well, until it wasn't.

There's no doubt that coal will go down as a miracle material in the cornerstones of human history. Despite its unending burden on human and planet health, it still contributes substantially to energy generation even in the 2020s, clamping down on its throne as the largest human-made source of climate change-worsening carbon dioxide.

We thought we had finally gotten to the bottom of the soot-laced barrel of coal's ill effects, but new studies point to some severe underestimations.

A doubly-dangerous pollutant

Coal burning creates copious amounts of sulphur dioxide, a fine particulate matter (PM2.5) that suspends in our air to form one of the most dangerous forms of air pollutants. While we've known this for a while, we've also been treating coal PM2.5 similar to what is produced from other PM2.5 sources.

Now, new research has shown that we were gravely wrong, noting that exposure to PM2.5 from coal-fired power plants is at least twice as dangerous as the fine particulate matter from other sources. This extra burden on human mortality amounted to a whopping 4,60,000 deaths related to exposure to this contaminant between 1999 to 2020 in the United States, representing a quarter of all deaths attributed to PM2.5 exposure till 2009.

To determine these results, the researchers assessed emissions data from 480 coal power plants in the US during the two-decade study period. They determined where the coal pollution would drift off to after burning, and then compared medical records of people living within the affected areas.

The findings were shocking, to say the least. The average level of coal PM2.5 reached a catastrophic 2.34 micrograms per cubic metre of air in 1999. In comparison, current levels hover around 0.07 in the US. From 1999-2007, this ridiculous amount of extra coal exposure resulted in 43,000 deaths yearly.

Fortunately, things have tapered off since then, with mortalities declining drastically to only 1,600 by 2020 — still a lamentable amount by any yardstick.

"Coal power plants were this major burden that U.S. policies have already significantly reduced," remarks author Corwin Zigler. "But we haven't completely eliminated the burden—so this study provides us a better understanding of how health will continue to improve and lives will be saved if we move further toward a clean energy future."

The authors explain that the installation of air scrubbers and shutting down of many plants helped this 95% decrease in coal-related deaths. As fortunate as this improvement is, studies still show that over one lakh Indians succumb to coal exposure every year. It is imperative we take the necessary steps to bring this number down further.

The findings of this research have been published in Science and can be accessed here.