Environmental Science Chapter 12 Review

Air Pollution Overview

• Air pollution occurs when harmful substances accumulate in the atmosphere to unhealthy levels.
• Major contributors include human activities, particularly the burning of fossil fuels and industrial emissions.

Pollutants

• Primary pollutants are emitted directly into the atmosphere, such as soot from smoke.
• Secondary pollutants form when primary pollutants interact with each other or with natural substances, like ground-level ozone.

Major Air Pollutants

• Key primary air pollutants include:
  • Carbon monoxide
  • Nitrogen oxides
  • Sulfur dioxide
  • Volatile organic compounds (VOCs)
  • Particulate matter
• Health and environmental impacts of these pollutants can include respiratory issues and ecosystem damage.

Legislation and Regulation

• The Clean Air Act grants the Environmental Protection Agency (EPA) authority to regulate vehicle emissions in the U.S.
• The California Zero-Emission Vehicle Program mandates that all cars sold in California must be zero-emission vehicles by 2016, meaning no tailpipe emissions and no gasoline emissions.

Industrial Emissions

• Industrial air pollutants result from processes like burning fossil fuels and electricity generation, leading to significant emissions of sulfur dioxide and nitrogen oxides, along with toxic VOCs.

Pollution Control Technology

• Scrubbers are machines designed to filter pollutants from gases using water sprays.
• Electrostatic precipitators are utilized in industries, such as cement and power plants, to eliminate dust particles from smoke.

Smog and Its Effects

• Smog is a type of air pollution that reduces visibility, formed by chemical reactions in the presence of sunlight and other pollutants. It is classified as a secondary pollutant.

Health Effects

• Short-term health issues may include headaches, nausea, and respiratory irritation.
• Long-term exposure can lead to severe conditions like emphysema, lung cancer, and heart disease.

Indoor Air Pollution

• Indoor air pollution arises from toxic substances found in building materials, furnishings, and paints, contributing to health risks such as sick-building syndrome.

Ground-level Ozone

• Ground-level ozone can cause respiratory irritation, reduced lung function, and aggravation of asthma.

Radon and Asbestos

• Radon gas is a colorless and odorless radioactive substance linked to lung cancer due to its ability to damage genetic material.
• Asbestos, once common in insulation, can cause asbestosis and serious breathing complications.

Noise Pollution

• Noise pollution affects health and quality of life, measured in decibels; exposure above 120 dB can lead to hearing loss.
• For reference, 20 dB is ten times more intense than 10 dB.

Light Pollution

• Light pollution results from excessive artificial light, obscuring views of the night sky.

Acid Precipitation

• Acid precipitation consists of rain or snow with high acid concentrations, primarily resulting from sulfur and nitrogen oxides combining with atmospheric water.
• It alters soil chemistry, potentially leaching nutrients and harming plants.

Acid Shock

• Acid shock occurs when melting acidic snow rapidly alters water pH, affecting aquatic ecosystems.

Global Impacts

• Acid precipitation is a transnational issue, with pollutants from one region affecting another, requiring global collaboration for effective mitigation.