Coal-fired power plants are twice as harmful to humanity as previously thought

Coal is the main source of electricity on earth today, it produces more electricity than gas and many times more than other electricity feedstocks. In the US, coal is being displaced by natural gas, but most countries do not have cheap gas. Therefore, globally, coal use is projected to continue to grow. In 2021, for example, it has become the growth leader in the power sector, overtaking the growth rate of renewable energy. In August this year it was reported that in Russia the share of coal by 2050 may not only not decrease, but even slightly increase.

Meanwhile, back in 1990, Harvard scientists linked tiny particles in the air, called PM2.5, to an increased risk of early death. Subsequent work has said that these particles increase the risk of lung and heart disease, cancer, and dementia. The main danger is that once in the bloodstream, they make it easier for blood clots to form, significantly increasing the likelihood of heart attacks and strokes, including fatal ones. All told, microparticles from burning fossil fuels kill about eight million people a year.

Now scientists from George Mason University and the University of Texas (USA) have found out that the impact of PM2.5 particles released into the atmosphere due to the activity of coal-fired power plants is twice as life-threatening as the impact of the same substances from other sources.

PM2.5 is the smallest particles of dust, ash, soot, and sulfate and nitrate in the air, ranging in size from 0.001 to 2.5 micrometers.

Because they are so small, they enter the lungs when inhaled, but are not trapped by biological barriers and pass into the bloodstream. They can build up in the body and lead to health problems. For example, to lung disease, cardiovascular disease and cancer. 

Now, U.S. researchers have examined emissions data from 480 coal plants from 1999 to 2020. They then created a model of the dispersion of sulfur dioxide (which is then converted to PM2.5) by the wind during the week after the emission. This way they were able to calculate the size of the area each power plant pollutes in a year. The model was then compared to the health records of the US population. The results were published in the journal Science.

Specialists found that about 460 thousand deaths were associated with PM2.5, released as a result of coal combustion. Most of them occurred between 1999 and 2007, when pollutant levels from coal-fired power plants were the highest. A one microgram/cubic meter increase in annual average particulate matter from coal plants was correlated with a 1.12% increase in the probability of premature death, which was 2.1 times the risk from exposure to PM 2.5 emitted from other plants.

According to the authors, their study once again showed that increased use of coal will harm human health. They called for turning to other energy sources as often as possible to reduce the negative impact of coal.

Although the data in the new paper comes from the U.S., it's clear: coal's weight in the global eight million annual deaths from microparticles is far greater than previously thought. It is apparently measured not in hundreds of thousands, but in millions of lives each year. This is especially dangerous given that the amount of coal burned will only increase in the foreseeable future.