Unit 7: Pollution

Air Pollution

The presence of harmful substances in the air, leading to adverse effects on human health and the environment.

Clean Air Act

A US federal law designed to control air pollution on a national level, including setting regulations on air quality and pollutants.

Air Quality Index (AQI)

A scale from 0 to 500 that measures air pollution levels, where higher values indicate worse air quality.

Primary Air Pollutants

Substances that are emitted directly from sources such as vehicles, power plants, and factories.

Secondary Air Pollutants

Pollutants that form when primary pollutants undergo chemical reactions in the atmosphere.

Particulate Matter (PM)

Solid or liquid particles suspended in the air, which can affect human health and the environment.

Volatile Organic Compounds (VOCs)

Organic chemicals that easily evaporate at room temperature and contribute to air pollution and smog.

Photochemical Smog

A type of smog that forms in the presence of sunlight and involves the reaction of nitrogen oxides and VOCs.

Nitrogen Oxides (NOx)

Gases that contribute to air pollution and can cause respiratory problems; primarily produced from combustion processes.

Ozone (O3)

A molecule composed of three oxygen atoms, where ground-level ozone is a pollutant that can harm lung function and plants.

Acid Rain

Precipitation that has a lower pH due to dissolved sulfur and nitrogen compounds, harmful to ecosystems and infrastructure.

Environmental effects of air pollution

Negative impacts on natural resources, human health, and ecosystems caused by the presence of pollutants in the air.

Indoor Air Pollution

Pollution that occurs inside buildings, often from sources like cooking, cleaning products, and building materials.

Carbon Monoxide (CO)

A colorless, odorless gas produced by incomplete combustion of fuels, which can cause suffocation and health problems.

Radon Gas

A radioactive gas produced by the decay of uranium in soil and rock, associated with lung cancer risk.

Noise Pollution

Excessive or harmful levels of noise in the environment, causing stress and hearing loss.

Light Pollution

Artificial light that brightens the night sky, disrupting ecosystems and human health.

Stratospheric Ozone

Ozone located in the stratosphere that protects life on Earth by absorbing ultraviolet (UV) radiation.

Anthropogenic Ozone Depletion

Depletion of ozone in the stratosphere caused by human-made chemicals like CFCs.

Montreal Protocol

An international treaty designed to phase out substances that deplete the ozone layer.

Air Quality Standards

Regulations set by the EPA under the Clean Air Act to limit pollutants harmful to health and the environment.

Lead Pollution

Contamination caused by lead, which is toxic and can have severe health effects, particularly in children.

Thermal Inversion

A weather phenomenon where warm air traps cooler air at the surface, preventing pollutants from dispersing.