Intro to Air Pollutants Notes - 7.3 to 7.6

Sources of NOx and SO2

SO2 - coal power plants, metal factories, vehicles that burn diesel fuels

NOx - vehicle emissions, diseal generators, coal power plants

Both are primary pollutants that cause acid rain

Limiting acid rain

Reducing NOx and SO2 emissions reduces acid deposition

• Higher CAFE (Corporate Average Fuel Economy) standards

• more public transit

• renewable energy sources

• more efficient electricity use

Sulfuric Acid formula

SO2 + O2 + H2O –> H2SO4

Nitric Acid Formula

NO2 + O2 + H20 –> HNO3

Environmental effects of Acid Rain

Acidification of soil and water pH effecting aquatic wildlife as well as reduced photosynthesis from damaged plant leaves.

Mitigating Acid rain

Reduce emissions of SO2 and NOx, Promote the use of renewable energy sources, Increase the use of scrubbers and other pollution control technologies, and intergrating limestone into buildings

• limestone is a natural base that can neutralize acidic water and soil to a pH of 7

Natural Sources of Air pollutants

lightning, forest fires, conifers, volcanoes

• small and temporary emissions

Natural Sources of CO2 and PM

Respiration, aerobic decomposition, natural PM (pollen, dust, ash) anaerobic decomposition

PM10

Particulate matter with a diameter less than 10 micrometers. These particles can come from natural sources like dust, pollen, ash, or human activities such as burning fossil fuels

PM2.5

particulate matter in the air that is less than 2.5 micrometers in diameter. These particles can be inhaled and enter the lungs, potentially causing various health problems such as chronic bronchities

Developing countries and indoor air pollutants

Developing countries use more biomass than developed countries due to how inexpensive it is. Burning biomass releases CO, PM, NOx, and VOCs

• combustion often happens indoors with poor ventilation, leading to a high concentration of each

• 3 billion people cook with biomass globally, and 3.5-4.3 million die from it annually

Developed countries and indoor air pollutants

Developed countries use more commercial fuels supplied by utilities. These are burned in closed, well ventilated furnaces and stoves

• major indoor pollutants from from chemicals in products such as cleaning supply, paints, and adhesives.

Asbestos

long, silicate particle previously used in insulation that is linked to lung cancer and asbestosis. It isn’t dangerous until disturbed but is common in old buildings

Carbon Monoxide (CO)

Produced by incomplete combustion of any fuel due to low O2 or temperature.

• an asphyxiant - causes suffocations due to CO binding to hemoglobin in blood, displacing O2

• Lethal to humans in high concentration as it is odorless and colorless

VOCs

chemicals used in a variety of home products that easily vaporize, enter air, and irritate the eyes and lungs

• adhesives, cleaners, plastics, and fabrics

Radon Gas

radiactive gas released by natural decay of uranium found in rocks underground, typically granite

• enters homes through cracks in the foundations then disperses

• can seep into groundwater

• 2nd leading cause of lung cancer behind smoking

Dust + Mold

Natura indoor pollutants that disturb the respiratory tract.

Mold - occurs in dark, damp unwell ventilated areas

• black mold especially harmful as they release spores into the air we can inhale

Lead

found in paint of old homes and can be inhaled by dust or eaten by small children, which can damage their central nervous system.

Lead pipes can seep into our water sources, but less common than paint.

Air pollution reductions

Drive less, walk more, conserve energy

passing of Clean Air Act

CAFE vehicle standards

pollution credits