Pollutants and Types of Pollution

• Lecture notes cover pollutants and types of pollution.

Pollutants

• Any substance or matter present in the environment that causes a change in its natural composition and has adverse effects on environmental receptors such as humans, plants, animals, water, soil, and air.

Contaminants (Temporary Pollutants)

• Any substance or matter that is not originally present in the environment but temporarily enters it and causes damage to the environment.
• Examples include:
  • Smoke from burning waste or crop residues during harvest season.
  • Dust resulting from seasonal winds carrying soil.
  • Chlorine gas from a tank explosion on the road or gas leak from a factory, and unpleasant odors.
  • Emission of pleasant odors from some factory products.

Permanent Pollutants

• Any substance or matter present in the environment in small quantities that has continuous adverse effects on environmental receptors.
• Examples include:
  • Substances produced by factories.
  • Sanitary wastewater.
  • Pesticides used in agriculture.
  • Lead from car exhaust on roads continuously throughout the day.
  • Waste resulting from metal and mining industries.
  • Waste present in sanitary wastewater permanently.

General Characteristics of Pollutants

• Source: The place where the pollutant originates.
• Receptor: The organism or component in the environment that is affected by the pollutant's effects.
• Incubator: The container or sink where the pollutant interacts and is retained in the environment.
• Path: The route through which the pollutant moves in the environment.
• Threshold Value: The minimum amount of a pollutant that, if exceeded, causes damage in the environment.
• Synergism: The combined effect of pollutants.
• Antagonism: Counteraction.

Types of Pollution

Pollution by Nutrients

• Results from fertilizers, nutrients, sewage, fish farms, and agriculture.
• Causes eutrophication, which is an increase in nutrients in the environment beyond what is required for living organisms.
• Ways to treat pollution by nutrients include:
  • Using fertilizers free of phosphates.
  • Reducing the use of fertilizers and agricultural enhancers.
  • Treating sanitary wastewater before using it in the environment.
  • Increasing plant cover in water courses and agriculture to reduce nutrients from water.

Pollution by Sediments

• Results from dust and dirt carried by wind to aquatic environments and negatively affects ecosystems due to the heavy metals, solid materials, and harmful organic compounds it carries in water.
• Sediments also result from poor mining practices, incorrect agriculture, and some radical changes in the environment.
• Solutions include:
  • Better management of farms and mines.
  • Avoiding large-scale environmental changes.
  • Planting tall trees with permanent cover.

Thermal Pollution

• Pollution resulting from an increase in the temperature of the environment and water bodies.
• This leads to a decrease in dissolved oxygen in the water and suffocation of aquatic organisms.
• Some human activities responsible for thermal pollution include industries, power plants, deforestation, earthquakes, and volcanoes, which lead to an increase in the temperature of water.
• Diverting cold water from industrial cooling reservoirs causes a change in the water's temperature and kills aquatic organisms.
• Effects of thermal pollution include:
  • Increased water temperature on the Earth's surface.
  • Reduced oxygen solubility in water with increased temperature.
  • Loss of large quantities of water from the environment.
  • Death of plants and living organisms.
  • Thermal shock to the aquatic environment, which is a sudden increase or decrease in the water temperature in the environment.

Natural Pollution

• Caused by earthquakes and volcanoes or any activity that leads to earthquakes and volcanoes such as large explosions and energy exploration (petroleum).