There’s no doubt about it – air pollution is bad for our health. Regularly inhaling polluted air can lead to pulmonary, respiratory and cardiovascular diseases, as well as exacerbate allergies and weaken the immune system.
Air pollution is defined as anything that contaminates the atmosphere by disrupting the air’s natural chemistry. Air pollutants can be divided into two categories:
- Primary pollutants: Pollutants emitted into the atmosphere directly from a source, for example volcanic eruptions or factory emissions.
- Secondary pollutants: Pollutants formed as a result of chemical reactions from primary pollutants in the atmosphere, such as the formation of ozone due to a chemical reaction between sunlight, organic gases, and nitrogen from vehicle emissions and factories.
While natural sources, such as volcanic eruptions, cause air pollution, human activities have contributed significantly to the increase in air pollution in recent decades. Some of the worst air pollutants today include:
- Particulate matter (PM): These are microscopic particles made up of various solid and liquid organic and inorganic compounds. They are harmful when inhaled, as they can penetrate the lung barrier and enter the bloodstream.
- Ozone: As explained above, ozone is formed when nitrogen emissions react with sunlight. High concentrations of ozone can cause skin and respiratory irritations (e.g. asthma) and pulmonary disease. It can also damage plant growth and negatively impact ecosystems.
- Carbon Monoxide (CO): An odourless, toxic gas released when fossil fuels such as coal and oil are incompletely burnt (e.g. exhaust emissions, gas-based household heating equipment, and industrial emissions). Prolonged inhalation can cause headaches, weakness, confusion, dizziness, and eventually, death.
- Sulfur dioxide (SO₂): A gas produced when fuels containing sulfur are burnt during industrial processes. It can lead to health complications for individuals with pre-existing heart and lung conditions.
Other major air pollutants that can negatively impact human health and the environment include nitrogen oxides, lead, volatile organic compounds (VOCs), dioxine, and benzene.
While it might seem like a daunting task, humanity must continue to work together to reduce emissions to protect human health and the ecosystems on which we depend for survival.
Keywords: primary pollutants, secondary pollutants, air pollution