Scientists have discovered the harmful effects of clean air

SciTechDaily: scientists have discovered the harmful effects of clean air

Photo: Still from video

Research shows that reducing air pollution may contribute to an increase in the incidence of a serious bacterial infection called Legionnaires' disease (Legionella pneumophila).

According to SciTechDaily, this respiratory disease, which has a mortality rate of 10-25%, is caused by inhaling Legionella bacteria. The bacteria live in water, and outbreaks have been linked to water sources such as cooling towers, which cool indoor spaces by dissipating heat into the atmosphere as droplets and water vapor.

Other sources include fountains, hot tubs, ice makers, home humidifiers and showers.

The global increase in Legionnaires' disease since 2000 has puzzled experts. In the United States, the number of reported cases of the disease grew from 1,100 cases in 2000 to almost 10,000 cases in 2018.

An international team that studied the trend and published its results in the journal Proceedings of the National Academy of Sciences attributes this increase with decrease in the level of air pollution with sulfur dioxide (SO2). Airborne water droplets carrying Legionella bacteria absorb SO2 from the surrounding air, which when SO2 levels are high can make the water droplets unfavorable for bacteria.

As SO2 pollution levels decrease, bacteria live longer in airborne droplets, increasing the likelihood entry of viable bacteria into human lungs. According to the authors, reducing SO2 pollution has many proven health benefits and should not be abandoned, but officials and doctors should be aware of the potentially increased risk of developing Legionella pneumophila.