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Protecting the air we breathe

| By Dorothy Lozowski

It has long been known, from advanced monitoring and modeling, that pollutants can linger in the air and travel long distances from their sources. Local air quality can therefore be affected by disturbances that happen in far-away parts of the globe. The atmosphere connects us, worldwide, making air quality a global concern.

Recently, the ability for polluted air to travel far with dramatic consequences was witnessed by many in North America. Wildfires covering an area reported to be over 10 million acres in Canada produced a heavily air-pollutant-laden plume that covered many areas of the United States with a dark, orange, eerie haze that was deemed unhealthy and even toxic by some reports. Areas stretching from Minnesota and Wisconsin to Maryland and New England had all been issued poor air quality alerts at some point during the plume’s movement.

 

Measuring the air quality

Many people, who were perhaps not yet familiar with it, learned about the Air Quality Index (AQI) — the U.S. Environmental Protection Agency’s (EPA) measure of air quality. The EPA establishes an AQI for five major pollutants — ozone, particulate matter, carbon monoxide, sulfur dioxide and nitrogen dioxide. The one of major concern from the wildfires was particulate matter less than 2.5 microns in size (PM 2.5). These fine particles are able to travel deep into the respiratory tract and are associated with numerous adverse health effects. The AQI runs from 0 to 500, with higher values indicating a higher level of pollution and greater concern for potential health issues. An AQI up to 50 is regarded as healthy, over 100 is unhealthy, over 200 is very unhealthy and over 300 is considered hazardous.

At one point last month, the AQI in New York City was reported to be over 400. Residents were advised to stay indoors and wear masks if going outside was essential. At the time of this writing, the wildfires are still raging and many are keeping track of their local AQIs as wind patterns shift.

These recent events and many others, whether from wildfires or other sources of air-pollution plumes, are a stark reminder of how important our air quality is.

 

The CPI is doing its part

With goals related to sustainability and combating climate change [1], the chemical process industries (CPI) are working toward reducing industrial air-pollution emissions. The American Chemistry Council (ACC; www.americanchemistry.com) reports that its member companies are investing in and deploying technologies to lower emissions. According to the ACC, its member Responsible Care facilities have reduced hazardous air pollutant emissions by approximately 24% from 2010 to 2020.

Our two cover stories this month focus on reducing air pollution from industrial sources. The first article (pp. 25–27) offers considerations in choosing between combustion and non-combustion air-pollution-abatement technologies. And the second article (pp. 28–30) discusses a proactive approach to reducing emissions.■

Dorothy Lozowski, Editorial Director

 

1. According to the U.S. Geological Survey (USGS; www.usgs.gov),there is no direct relationship between climate change and wildfires, but they say there is a general consensus that fire instances will increase with climate change.