Environmental Issues and Problems: Wastes and Pollution

Environmental Issues and Problems: Wastes and Pollution

Learning Outcomes

• Define pollution and the term "pollutants."
• Explain types of pollution, their causes, and effects.
• Enumerate sources of solid and hazardous wastes.

Key Concepts

• Pollutants vs. Contaminants

  • All pollutants are contaminants, but not all contaminants are pollutants.
  • Contamination occurs when unwanted substances make an environment impure; can be from human or natural sources.
  • Pollution is the introduction of harmful substances into the environment, negatively impacting human health and ecosystems.

• Bioaccumulation and Biomagnification

  • Bioaccumulation: Gradual build-up of pollutants in an organism.
  • Biomagnification: Increase in concentration of harmful substances as they move up the food chain.

Types of Pollution

Water Pollution

• Caused by the entry of toxic substances into water bodies.
• Causes:
  • Domestic wastes (nitrates, phosphates).
  • Industrial wastes (toxic chemicals).
  • Agricultural wastes (fertilizers, sediments).
• Effects:
  • Eutrophication leads to algal blooms and oxygen depletion.
  • Diseases from contaminated water (typhoid, cholera).

Air Pollution

• Result of pollutants released into the atmosphere.
• Causes:
  • Industrial emissions (CO, SO2).
  • Automobile emissions (VOCs like benzene).
  • Burning of fossil fuels.
• Effects:
  • Photochemical smog and enhanced greenhouse effect.

Soil Pollution

• Presence of pollutants in soil that pose risks to health.
• Causes:
  • Mining, waste disposal, agricultural practices.
• Effects:
  • Acidification, crop loss, risks to human health.

Solid and Hazardous Wastes

• Solid Waste: Non-hazardous wastes like household trash, construction debris.
• Hazardous Waste: Dangerous wastes (toxic chemicals, medical wastes) that pose significant health and environmental risks.
  • Generated mainly in industrial processes, improper waste disposal, and during mining activities.

Global Impact

• Statistics: 7 million annual deaths due to air pollution; Philippines leads in ocean plastic pollution (36% of global total).
• Growing awareness and efforts to mitigate pollution and manage waste effectively.