According to EPA, air quality in the US is declining over the last few years despite all the progress.
A rise of 15% more days with polluted air was recently reported, compared to last decade!
This recent decline in air quality is being associated with the warming climate, increasing fossil fuel consumption, and wildfires.
But these are not the only sources of air pollution.
Air pollutants come from many different sources, both natural and man-made.
Some of the major air pollutants, their sources and exposure mechanism are as following:
- Carbon monoxide
CO is an invisible, odorless gas. It results from the incomplete combustion. Major sources of carbon monoxide include automobile emissions, industrial activities, and fire. Its exposure can cause severe health effects as it replaces oxygen in the bloodstream. It results in heart diseases, vision problems, fatigue, and reduced physical and mental capabilities.
- Nitrogen oxides
Nitrogen dioxide and nitrous oxide have a pungent smell and are major urban air pollutants. They come mostly from automobile emissions. They are also formed when molecular nitrogen in the air is mixed with oxygen at high temperatures. Coal-burning power plants, electricity generation, and industrial processes are also major contributors of this air pollutant. Nitrogen oxides accumulate in the lungs and cause inflammation and irritation to respiratory organs. Moreover, it forms nitric acid which poses a problem in the form of acid rain. Nitrogen dioxide also plays a role in forming photochemical smog in urban areas.
- Sulfur dioxide
Sulfur dioxide is a colorless gas and has a sharp smell. It forms when sulfur-containing fuel is burned. Mostly sulfur dioxide emissions originate from electricity generation, fuel combustion, and some industrial processes. Automobile emissions are also a source of sulfur dioxide. Health effects of sulfur dioxide include eyes, nose and throat irritation, and breathing difficulties. Lung tissues can also be affected if this pollutant is inhaled. Just like nitrogen oxides, this gas is a component of acid rain.
Ground-level ozone is a major air pollutant. It forms when nitrogen oxides and hydrocarbons react in the presence of sunlight. Other sources include electrical appliances, chemical solvents, and emissions from vehicles and industries. Ozone affects the normal functioning of the lungs and causes irritation in the respiratory tract.
- Particulate matter
Particulate matter refers to microscopic solid or liquid particles that are suspended in air and are extremely hazardous due to their small size. The most commonly studied of them are PM 10 and PM 2.5. These usually come from fossil fuel burning, industrial processes, automobile exhaust, fire, and construction activities. These are easily inhaled and affect the respiratory system and other vital organs. Some of the particulate matter are known carcinogens. PM 2.5 accounts for the most health effects because of urban air pollution in the United States.
Lead particulates come from oil refineries, metal smelting, waste incineration, combustion of fossil fuels, and other industrial activities. It is particularly harmful to children. Lead poisoning results in learning disabilities in children and cardiovascular effects in adults.
The above-mentioned air pollutants are called “Criteria Air Pollutants (https://www.epa.gov/criteria-air-pollutants/naaqs-table)” because their concentrations in the air indicate overall air quality.
As mentioned earlier, air pollutants come from both natural and man-made origins.
Wildfire smoke, gases released during volcanic eruptions, and decomposition of organic matter are some of the natural sources of air pollution.
Traffic-related air pollution is one of the most recognizable human-made air contamination.
Power generation and its usage, product manufacturing, industrial processes, waste incineration, metal smelting, construction activities, and release of CFCs are some of the primary sources of man-made air pollution.
The next time you ride your bike to school, walk, or commute on a smoggy day, then consider masking up with WEBREATHE's Urban Air Snood 1.0. It's an easy solution you can do right now to avoid breathing toxic air.