outdoor air pollution 7.1

Carbon Monoxide

Colorless, odorless gas that interferes with the uptake of oxygen.

Sources of Carbon Monoxide

Motor vehicle exhaust, kerosene or wood burning stoves, and anywhere there is incomplete combustion.

Health Effects of Carbon Monoxide

Acts as an asphyxiant, affecting oxygen uptake; can harm fetal development and lead to death.

Lead

A heavy metal toxic to humans, found in metal refineries, battery manufacturers, and iron/steel production.

Lead Phaseout

The EPA began phasing out lead as a gasoline additive in 1974.

Catalytic Converters

Required in vehicles made after 1974 to reduce NOx, CO, and hydrocarbon emissions.

Health Effects of Lead

Known neurotoxicant causing brain and kidney damage, lowered IQ, and anemia.

PM10

Particulate Matter smaller than 10 micrometers, includes dust, pollen, and ash.

PM2.5

Particulate Matter smaller than 2.5 micrometers, more likely to travel deep into the lungs.

Health Risks of PM2.5

Associated with chronic bronchitis and increased risk of lung cancer.

Nitrogen Oxides (NOx)

Reddish brown gas released during combustion of fossil fuels and biomass.

Formation of NOx

NO forms when nitrogen combines with oxygen, especially during combustion.

Health Effects of NOx

Respiratory irritant causing cough, chest pain, and difficulty breathing.

Environmental Impact of NOx

Contributes to tropospheric ozone formation and acid precipitation.

Formation of Photochemical Smog

Occurs when sunlight breaks NO2 into NO and O, leading to ozone and photochemical oxidants.

Factors Increasing Smog Formation

Increased vehicle traffic, higher VOC emissions, warmer temperatures, and urban settings.

Ozone as a Secondary Pollutant

Gaseous pollutant formed in the troposphere from vehicle exhaust and VOC fumes.

Health Effects of Ozone

Causes eye and throat irritation, coughing, asthma, and lung damage.

Environmental Effects of Ozone

Damages plants, affecting their ability to produce food and increasing vulnerability.

Sulfur Dioxide (SO2)

Colorless gas from coal-fired power plants, petroleum refineries, and burning diesel.

Health Effects of SO2

Causes respiratory irritation, worsens asthma and bronchitis, and leads to eye irritation.

Environmental Impact of SO2

Forms sulfurous smog, blocking sunlight, reducing photosynthesis, and contributing to acid rain.

Formation of Acid Rain

Occurs when NOx and SO2 react with O2 and H2O to form nitric and sulfuric acid.