Lecture 6 - Air Pollution

What are criteria air pollutants? Name all criteria pollutants. Know their health effects.

"criteria pollutants" are pollutants for which the U.S. EPA has decided there is sufficient scientific evidence of health and/or welfare effects to provide a basis for regulating ambient levels Lead: can be in food/air/soil; bioaccumulates? in bone and teeth; linked to IQ deficits/CNS damage CO: colorless/odorless/tasteless; produced as result of incomplete combustion; source - motor vehicles, home heating appliances, combustion sources; displaces Hb fxns because has higher affinity to Hb than O2; other effects include shortness of breath, headaches, and can be fatal NOx: source - combustion, vehicles, industry; O3 precursor; mild respiratory irritant, irritation of eyes/nose/throat, increase respiratory infections Sox: source - combustion, power plants; respiratory irritant, reduced lung function, bronchoconstriction, eye irritations, adverse pregnancy outcomes, mortality, hospitalization from cardio/respiratory causes O3: "smog" created by Nox and VOCs in presence of sunlight, by-products of ozone also makes smog; O3 highest in the summer during mid-afternoon bc this rxn needs sunlight and heat (VOC + NOx + sun + heat O3); O3 highest in cities that get sunlight, i.e. Phoenix, LA, Houston; no threshold; acute exposure - coughing, chest pains, headaches, eye / throat irritation, nausea, asthma attacks, loss of lung capacity, respiratory damage; chronic exposure - Changes to immune system, aging of lung tissue, loss of lung tissue, susceptibility to respiratory infection, asthma/bronchitis PM: particles of liquid/solid dispersed as a suspension in gas; no threshold; respiratory/cardiovascular diseases, premature mortality, increased hospital/ER admissions, increased morbidity and mortality

What is PM or Aerosol? Particulate matter sizes and health effects.

Aerosols are particles of liquid or solid dispersed as a suspension in gas; no threshold; cardio/respiratory effects, eye/nose/throat/lung irritation, coughing, pulmonary (asthma/bronchitis), infants/elderly particularly sensitive 10 micrometers is the biggest that can affect humans 2.5 - 10PM: course particles, not as bad as fine particles, formed from mechanical processes (wind erosion, etc), efficiently removed from atmosphere by gravitational settling forces usually in a few hours to days; deposits in nose and throat 0.1 - 2.5PM: fine particles, formed mostly from combustion, very hard to remove from atmosphere and persists for days to weeks; deposits in deep lungs 0.1PM: ultra particles

Clean Air Act (CAA)

Clean Air Act: 1970 federal law that regulates air pollution originating from area sources (large location, i.e. farmland/landfill), stationary sources (power plants/factories), mobile sources (cars); controls air pollution on a national level, one of U.S.'s first and most influential modern environmental laws and one of the most comprehensive air quality laws in the world; authorizes EPA to set standards (NAAQS) of "criteria pollutants" that are linked to adverse health and welfare effects

What is an inversion layer?

It is a reversal of the normal decrease of air temperature with altitude, or of water temperature with depth. Ground level pollution gets trapped and cannot move upward anymore so it starts concentrating at that ground level and worsening effects of that place. Ground is typically warmer during the day/temperature gradient; at night, top layer is still cold but ground loses heat very fast which causes air to be dense so exhaust at ground level gets trapped and causes thick inversion layer; warmer air above (clean) cannot cool fast enough to penetrate inverted layer below; then when sun rises, ground warms up fast and air on top is now cooler so warmer air now escapes; air pollution travels horizontally

Regulatory agencies: EPA, ARB in CA, and APCD in SD

National: Environmental Protection Agency (EPA) - Federal Air Quality Standards, National Emission Standards for Hazardous Air Pollutants, not only have standards but consequences if you do not follow, federal makes baseline standards but states make stricter standards if it chooses California: California Air Resources Board (ARB) - State Air Quality Standards, Airborne Toxic Control Measures, California has one of the strictest standards of all states San Diego: San Diego Air Pollution Control District (APCD) - APCD authority comes from federal and state clean air acts, must comply with state regulations, adopts local rules/laws designed to achieve attainment with state and federal air quality standards

Why is outdoor air quality regulated more effectively than indoor air quality?

Outdoor air pollution has specific laws, dedicated agencies, and clear strategies to protect health, but for indoor, no agencies at the federal, state, or local levels have overall responsibility for conditions in homes/buildings.

What are our major air quality problems in San Diego? San Diego is in non-attainment for which pollutants? What factors cause/ exacerbate the problem?

Primary pollutants are generated on the coastal plain. The mountains to the east trap pollutants within the county. Pollution is transported South from Los Angeles during Santa Ana conditions. San Diego is in non-attainment for ozone and particulate matter

National Ambient Air Quality Standards (NAAQS)

Standards (set by US Environmental Protection Agency under Clean Air Act) for "criteria pollutants" to protect public health and welfare 6 pollutants: Lead, carbon monoxide, nitrogen oxides, sulfur dioxide, ozone, PM Ex: O3 exposure for 1hr is acceptable at 0.12ppm, but exposed for longer like 8hrs then needs to be 0.075ppm Primary standards protect health of populations; secondary standards protect damages to crops, soil, water, buildings

What is ground level Ozone? How is Ozone formed?

This is known as "Smog" and is created by chemical reaction between NOx and VOCs in the presence of the sun Anything that releases hydrocarbon fuels produces VOC, any industrial rxns produces NOx Know that both PM and O3 have no threshold.

Movement up the household "Energy ladder"

electric lines come directly to house so makes sense to have stove in our homes, but some places don't so rely on simple cooking methods like using bricks/mud/dung; as a country develops, they are able to move up the energy ladder with increasing development (economic), and as they move up, they gain cleanliness, energy efficiency, cost; not a straight transition, it's a step by step process (solid fuels -> mixed -> non-solid fuels)

List the world's cooking fuels

electricity 14%, wood 23%, gas 24%, coal 6%, kerosene 11%, other biomass 22% electricity, kerosene, gas most common in developed countries sometimes coal, wood, biomass most in non-developed countries Low GDP per capita = more ppl use solid fuel for energy