About Pollutants

According to the website Green Student U, factories in the United States release over 3 million tons of harmful chemicals into the atmosphere every year. These chemicals pollute our air, land and water supply causing severe damage to the ozone and Earth, as well as serious health problems. Factories are not the only source of pollutants; various other sources, such as vehicle emissions, landfills and power plants, also contribute to this problem.

Definition

• Pollutants are substances that contaminate the natural environment, causing harm or damage to the ecosystem. They are either physical or chemical and derive from sources such as smoke, heat and gas. Pollutants come in several forms, including particulate matter and gases. Particulate matter consists of small solid particles and includes smoke, dust, pollen and sand. Gas pollutants include carbon monoxide, sulfur dioxide, nitrogen oxide and volatile organic compounds. Bacteria and algae are also considered pollutants, especially when they cause adverse effects in bodies of water, such as oceans, rivers and pools.

Classification

• Pollutant are classified as either primary or secondary, depending on their form. Primary pollutants retain their form when released into the atmosphere. For instance, the ash produced from burning waste is considered a primary pollutant. A secondary pollutant cannot sustain its original form when released into the environment and changes chemically in the atmosphere. An example of a secondary pollutant is ozone derived from vapors emitted from a gas station. The ozone is a secondary source caused by the reaction of the vapors with sunlight.

Sources

• There are three major types of pollution including air pollution, water pollution and land pollution. Land pollution is contamination of the Earth's infrastructure. Some sources of land pollution are chemical and nuclear plants, oil refineries and industrial factories. Air pollution is the accrual of pollutants in the Earth's atmosphere. Sources for air pollution include automobile emissions, large ships, tobacco smoke and nuclear weapons. Water pollution occurs when physical, biological or chemical contaminants enter large bodies of water. Oil spills, animal waste and human sewage are some of the sources of water pollution.

Effects

• The effects of pollutants are seen in all areas of life. Green Student U approximates that the average adult inhales 3,000 gallons of polluted air on a daily basis. This contributes to respiratory problems such as asthma and lung cancer, which causes about 335,000 deaths every year. According to the website, "1.2 millions gallons of sewage, storm water and industrial waste are discharged into U.S. waters every year," making it hard for aquatic animals and plants to survive.