It can inflame breathing passages, decreasing the lungs' working capacity, and causing shortness of breath, pain when inhaling deeply, wheezing, and coughing. It can cause eye and nose irritation and it dries out the protective membranes of the nose and throat and interferes with the body's ability to fight infection, increasing susceptibility to illness. Hospital admissions and respiratory deaths often increase during periods when ozone levels are high. EPA has developed an Air Quality index to help explain air pollution levels to the general public.
However, it is worse during periods of warmer, sunnier weather when the upper air is warm enough to inhibit vertical circulation. Reference Terms. In the s a new type of smog, known as Photochemical Smog, was first described. Smog is a problem in a number of cities and continues to harm human health.
This is why smog is more of a problem on hot summer days. Nitrogen oxides are produced by burning fossil fuels such as coal, oil, gas, and diesel in motor vehicles, industries, power plants, and homes. VOCs include carbon-containing gases that are created when gasoline and other oil-based solvents are burned.
Studies show that every major Canadian urban centre has levels of ground-level ozone that are high enough to pose health risks. Ozone is not only a problem for people; it damages vegetation and degrades man-made materials. It is a powerful greenhouse gas and contributes to climate change.
The other component of smog is fine particulate matter. Fine airborne particles are usually 10 micrometres in diameter or smaller and are a mixture of solid particles and liquid droplets, usually soot and acids, that can also be described as acid water droplets or acid aerosols. The particles are microscopic and remain suspended in the air for some time. Particulate matter decreases visibility and contributes to the brownish-yellow colour that is characteristic of smog.
It can be generated naturally by dust, sea salt spray, or windblown soil and pollen, but studies show that particulate matter generated from human activities is more harmful. Visit the Government of Canada for information of smog in Canada, and how to reduce your risk of its adverse effects.
Smog affects much more than just human lives; it also has a large impact on the surrounding physical environment. Ozone and PM in particular cause damaging effects: [2]. Ozone can damage plant cells and inhibit their growth, reducing the amount of carbon dioxide that they take in during photosynthesis. This results in reduced agricultural yields in all sorts of crops. It can also affect synthetic materials like rubber, cotton and other materials, causing deterioration and even disintegration.
Particulate matter smothers plants limiting their exposure to the sun and inhibiting their ability to take in carbon dioxide, therefore, decreasing its photosynthesis capabilities. The chemical composition of the PM may also have an effect on the plants and their surrounding soil.
Particulate matter causes the presence of haze in the air, thus reducing the clarity and colour of what can be seen. Humidity of the surrounding air also plays a role in its hazy effect.
According to the U. Environmental Protection Agency, visibility is reduced from kilometers to around 30 kilometers in certain parts of the United States. Visit Environment Canada for more details.
Fossil Fuels. Nuclear Fuels.
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