Lecture 22 | Air Pollution

Stationary & mobile sources of air pollution, primary & secondary pollutants, 6 criteria pollutants, inversion layers, stratospheric ozone & CFCs, indoor air pollution, & sick building syndrom

What were the first references to air pollution?

acid raid 1852 & smog 1905

Stationary Air Pollution Sources

fixed locations, point, fugitive, and area

Stationary Point Sources

smokestacks, landfills, factories

Stationary Fugitive Sources

open spaces exposed to wind, temporary, burning crops, construction, mines

Stationary Area Sources

areas with mixed pollution sources, non-point source, housing developments, farms

Mobile Air Pollution Sources

move around, anything with engine that consumes fuels

How many people are affected by air pollution? How much money is spent on healthcare in the US? 

175 million, $50 billion

What are the human health effects of exposure to air pollution?

cancer, irritation, heart disease

How can air pollution spread to different mediums? Give an example:

deposit in soil and water, mercury from coal burning in aquatic food chain

Primary Pollutants

emitted directly into the air: co, nox, sox, vocs, particulate matter

What type of pollutant is CO? How does it end up in the atmosphere?

primary, incomplete combustion in cars or natural decomposition

Secondary Pollutants

formed later from interactions between primary pollutants & other atmospheric substances

What are two secondary air pollutants?

sulfuric acid/acid rain and ground level ozone

What type of pollutant is ground level ozone (GLO)? How does it form?

secondary, reaction between no, o2, and sunlight

Criteria Pollutants

6 most heavily regulated air pollutants, sncgpl: sox, nox, co, glo, pm, lead

What are the most common sulfur oxides?

so2, so3

Where do sulfur oxides come from?

burning coal

How do sulfur oxides impact the environment?

corrode crops, paint, & metal, acid rain

What is the impact of sulfur oxides on human health?

react with water in lungs & cause lung damage

Which criteria pollutant creates secondary pollutants acid rain and smog?

nox

Where do nitrogen oxides come from?

fossil fuel combustion & automobile exhaust

What are the most common nitrogen oxides?

no2, no

What is the effect of nitrogen oxides on the environment?

create secondary pollutants acid rain & smog, deposits in water & eutrophication

What are the effects of nitrogen oxides on human health?

irritation & viral infection susceptibility

Where does carbon monoxide come from?

90% natural, 10% car exhaust or combustion

How does CO affect the environment? How does it affect human health?

doesn’t affect environment, taken up in blood 250x faster than o2, aggravate heart conditions & birth defects

How is ground level ozone created? What type of criteria pollutant is it?

photochemical reaction of nox, o2, sunlight, secondary

What makes O3 so difficult to regulate? How does it affect the environment?

secondary pollutant, damage leaf tissue & kill plants

What are the effects of GLO on human health?

airway irritation, difficulty breathing, chemical burns in lung

How is particulate matter produced?

industrial processes, power plants, automobiles, farming, & wind storms

How do particulate matter particles affect human health? How many people die in the US a year because of it?

embed in lungs, reduce o2 transfers, 60,000 die

How might particulate matter in the upper troposphere impact the environment? Where does it come from?

form clouds reflects sunlight & decreases climate change, comes from jets

Where does lead come from?

leaded gasoline and smelting/refining ores

How does lead interact with the environment?

heavy metal deposited quickly in soil & water, enters plants & food web

How does lead affect human health? What has this lead to?

affects central nervous system & brain damage/low IQ, reduce atm lead by 95%

Inversion Layer

traps pollutants under a lid of warm air over cooler air

How do inversion layers worsen air pollution?

trap pollutants in a small area, build up concentration

Describe how an inversion layer affects Los Angeles:

mountains keep sea breeze from air pollution moving laterally, inversion layer keeps a lid on them

Ozone is a harmful pollutant in the ______ but it protects us from harmful ration in the______

troposphere, stratosphere

Why are chlorofluorocarbons dangerous in the stratosphere?

break down O3, no mixing & remain in atm for 75 years

How can such a small amount of chlorine atoms create an effect as large as the ozone hole?

cl reacts with o3 to form clo and o2, then reacts with more o3 to reform cl and o2, which continues to react until 1 atom destroys 1 million ozone molecules

What regulation has led to the slow decrease in the size of the ozone hole?

montreal protocol, banned cfcs

Why is indoor air pollution so dangerous?

people spend most of their time indoors, little air circulation inside

List 10 sources of indoor air pollution:

hvac, mold/fungi/pollen, furniture/carpets, machines/tech, pesticides, smoking, paint, cleaning products, idling cars, radon

Sick Building Syndrome

when people in a building all develop similar illnesses/symptoms with no known cause

Why has sick building syndrome increased?

buildings sealed tight for energy conservation

How can sick building syndrome be reduced?

more air mixing, find & remove indoor air pollution sources