air pollution

troposhere air pollution

smog, particles, heavy metals, acid rain, human health and environmental impacts

smog

water and nitrogen dioxide can create pollution (smog) by reacting with atomic oxygen to form ozone 

smog creation process

1. sunlight breaks down nitrogen dioxide into nitric oxygen and atomic oxygen

2. atomic oxygen and molecular oxygen form ozone

3. VOCs react with ozone to form a harmful photochemical smog in the troposphere

surface air quality monitoring sites

BEACON; tracks hyperlocal variations in air quality, such as spikes in early morning driving

big picture pollution

natural, vehicle, and stationary sources are transported into the atmosphere, engage in chemical reactions with ozone, and lead to haze and deposition

clear air act

requires EPA to set national ambient air quality standards (NAAQS) for 6 commonly found air pollutions called criteria pollutants

criteria pollutants

1. ground level ozone

2. particulate matter

3. carbon monoxide

4. nitrogen dioxide

5. sulfur dixode

6. lead

primary standards

public health protection, sensitive populations

secondary standards

visibility (haze), and damage to animals, crops, vegetation, and buildings

clear air act results

between 1970 and 2023, combined emissions of 6 criteria pollutants dropped by 78%

carbon monoxide

comes from incomplete combustion of the burning of fossil fuels and wildfires, reduces oxygen transported in bloodline, disguises as oxygen

where are high carbon monoxide levels

big cities, road networks, east coast, showing strong correlation between carbon dioxide, carbon monoxide, and daily activities

nitrogen dioxide

emissions from burning of fuel in air (cars, trucks, buses, power plants, and off road equipment), form particulate matter and ozone, affecting respiratory system

nitrogen oxide radical

forms from nitrogen (air) in high temperature combustion, creating nitric acid (acid rain)

ground level ozone

not emitted directly into the air, created by chemical reactions between nitrogen oxide radicals and VOCs in the presence of sunlight and heat

ground level ozone negative impacts

people with asthma, vegetation, forests, and crops, big chunk from highway vehicles, lots of ozone in LA, phoenix, and Houston 

particulate matter

mix of solid particles and liquid droplets

PM10

inhalable particles with diameters generally 10 um and smaller

PM2.5

fine inhalable particles with diameters generally 2.5 um and smaller, causes serious respiratory health issues, primary cause of haze

where does P2.5 come from

direct emissions, but also mostly chemically in the atmosphere (VOCS, sulfur dioxide, and nitrogen dioxide radical)

toxic pollutants

known to cause cancer and have serious health impacts, organics and heavy metals, Clean air act regulates some industrial emissions for 188 toxic air pollutants

air quality index

days with unhealthy for sensitive groups classification, areas with lower incomes and higher percentages of people of color had higher PM2.5 levels

Pm and burden

overtime there has been reduce mortality burden based on declining concentration and based on number of people sensitive decreasing

ozone and burden

overtime, mortality burden has gone up as more people are sensitive to it, even though concentration has generally gone down.

air pollution and deaths

air pollution is 2nd highest death risk factor