1. Pollution (25-30%) **VERY IMPORTANT!! a. Pollution types i. Air Pollution 1. Sources (pg420-421) a. Primary – emitted directly into the troposphere in a potentially harmful form: CO

(cigarettes, motor vehicle exhaust), CO2 (fossil fuel emissions), SO2 (coal burning power plants), NO and NO2 (motor vehicle exhaust), most hydrocarbons, most suspended particles b. Secondary – when primary pollutants react with one another to form new pollutants:

SO3, HNO3, H2SO4, H2O2, O3, PANs 2. Major Air Pollutants (table 17-2, pg422) a. Carbon Monoxide (CO) – from incomplete combustion of fossil-fuels

b. Nitrogen Dioxide (NO2) – reddish-brown gas that colors photochemical smog, from motor vehicles/industrial plants (causes lung damage)

c. Sulfur Dioxide (SO2) – from coal-burning plants (causes breathing problems) d. Suspended Particulate Matter (SPM) – small particles that stay suspended in the atmosphere from coal/fuel burning, agriculture (lead to lung irritation)

e. Ozone (O3) – from photochemical smog (leads to breathing problems), harmful in the troposphere f. Lead – old houses, paints, leaded gas (bioaccumulation/biomagnification – brain damage) 3. Measurement Units – usually ppm (parts per million – or mg /Kg) or ppt (parts per thousand – or mg/g or g/Kg) 4. Smog (pg423-425) a. Brown-air smog: called photochemical smog (activated by light – happens during the day, most common is cities), 3 main reactions:

i. Nitrogen and Oxygen in air react in high-T car engines/industrial plants: N2 + O2  2NO ii. Nitric Oxide reacts w/Oxygen to form brownish gas, nitrogen dioxide: 2NO + O2  2NO2 iii. Reacts w/water to make nitric acid *a form of acid rain: 3NO2 + H2O  2HNO3 + NO 1. Can also have: NO2 + UV radiation  NO + O 2. O is very reactive, acts w/oxygen in air to form ozone in troposphere: O2 + O  O3 a. Ozone is VERY bad in the troposphere b. Gray-air smog: called industrial smog – mainly from coal-burning power plants (not a big problem in developed countries b/c of better pollution control systems; problem in urban areas of China, India, etc.); main reactions:

i. S + O2  SO2 ii. SO2 + O2  2SO3 iii. SO3 + H2O  H2SO4 (*a form of acid rain) iv. When burned, the carbon in coal/oil is also converted: C + O2  CO2 and 2C + O2  2CO 1. Carbon particulates also go into the air as soot 5. Acid deposition (pg428-431):

a. Causes: photochemical/industrial smog (see above), nitric (HNO3) and sulfuric acid (H2SO4) from nitrogen dioxide (NO2) and sulfur dioxide (SO2) b. Effects:

i. Human Health: contributes to respiratory disease, can cause leaks of toxic metals into drinking water pipes, can damage statues

ii. Aquatic systems: fish populations have low range of tolerance, cant survive below pH of 4.5

iii. Plants/Soil: leaches plant nutrients from the soil, damages leaves, can release metals into the soil (worst for areas w/acid soil – can be buffered

w/basic soils containing CaCO3 or limestone) 6. Heat islands (fig25-13, pg670) – cities are warmer, rainier, foggier, cloudier than suburbs and rural areas b/c of heat generated by multiple pollutants (cars, factories,…) in the area 7. Temperature inversions (pg426-427, fig17-9) – when cool dense air gets stuck beneath a layer of less-dense warm air (b/c cool air is more dense, air doesn’t mix and pollutants are stuck near the surface); most often occurs in areas w/sunny climate, light winds, mountains on 3 sides, ocean on the other side (like Los Angeles, CA) 8. indoor air pollution (pg434-436, fig 17-17) – many pollutant level are 2-5x higher inside than outside, leads to higher risk of cancer and costs $$ b/c of absenteeism, some main ones: a. Asbestos (from pipe insulation, floor tiles) – can cause lung cancer b. Tobacco smoke (from cigarettes) – can cause lung cancer c. Formaldehyde (from furniture stuffing, insulation) – throat/lung irritation d. Radon (from radioactive soil near foundation) – causes lung cancer e. New Building syndrome – being in new buildings causes sickness b/c of reduced air exchange, chemicals from new carpets/furniture 9. remediation and reduction strategies (pg440-444) a. Rely more on PREVENTION than cleanup: mass transit, biking/walking, etc. b. Increase fuel-efficiency in cars c. Use marketplace to reduce pollution – incentives (tax credits), and penalties – 1990

Clean Air Act allowed emission trading policy to buy/sell SO2 pollution rights (companies could use a certain amount of SO2, if they used more, then they would have buy it from a company that didn’t use all of their allowed amount)

i. Burn lower-sulfur coal (anthracite) ii. Shift to less-polluting fuels iii. Remove particulates from industrial plants (fig17-23, pg442): electrostatic precipitator, baghouse filter, cyclone separator, wet scrubber(removes SO2 particles) 10. Relevant Laws a. Clean Air Act – air pollution standards for primary/secondary pollutants, identify “criteria pollutants” (the ones that most threaten human health), require auto emission testing for states b. Asbestos Hazards and Emergency Response Act (1986) – requires schools to be inspected for asbestos ii. Noise Pollution (pg670) 1. Sources: anything that causes you to raise your voice to be heard, causes your ears to ring 2. Effects: above 85 dbA can cause permanent damage after 8 hours; decibel levels of common things: lawn mower (90 dbA), Chain saw (100 dbA), Rock music (110 dbA)… 3. Control Measures – modify noisy devices to produce less noise, shielding noisy devices, shielding workers from noise, moving noisy operations away from people iii. Water Pollution 1. Types (table 19-1, pg484) a. Infectious agents (bacteria – like typhoid fever, cholera, bacterial dysentery; viruses; parasitic worms) – from human/animal waste b. Oxygen demanding waste (from sewage, animal feedlots, paper mills) – populations of bacteria that deplete dissolved oxygen in water c. Inorganic chemicals (from surface runoff, household cleansers) d. Organic chemicals (like gas, oil, pesticides, cleansing solvents) – can cause nervous system damage, harm wildlife e. Plant nutrients (fertilizer – nitrates, phosphates) – can cause algae blooms, lead to fish kills f. Sediment (soil, silt) – from land erosion g. Radioactive materials (from nuclear power plants) – can lead to mutations, birth defects, cancers h. Heat (thermal pollution) – lowers dissolved oxygen *high T = less gases dissolved in water 2. Sources (pg486, fig19-4)) a. Point sources – discharge pollutants at specific locations (ex: factories, sewage treatment plants, underground mines). Easy to identify, monitor, regulate b. Non-point sources – can not be traced to a specific source of discharge (ex: acid deposition, runoff from agriculture – sediments, inorganic fertilizers, manure, pesticides), animal feedlots, lawns, etc). Hard to control b/c of the difficulty/expense of identifying/controlling discharges 3. Causes (pg486) – see above…urban streets, suburban developments, wastewater development plants, factories, cropland/agriculture (sediments, inorganic fertilizers, manure, salts in irrigation water, pesticides), rural homes a. in oceans: pollutants, waste, oil (leaked from tanker and drilling accidents; runoff from land activities) 4. Effects: a. Oceans/Sea (pg496-498, fig19-12) – ultimate sink for much of the waste materials we produce, can dilute, disperse, degrade large amounts of sewage and wastes – can lead to harmful algae blooms that kill fish. Mainly effects coastal areas (wetlands, estuaries, coral reefs, mangrove swamps) which is where many people are located

i. Chesapeake Bay – largest estuary in the US – receives wastes from point/non-point sources from 9 large rivers, 141 smaller streams; pollution sink b/c very shallow and water flows slowly – in 1983, created integrated coastal management program which worked; dropped nitrogen- phosphorus levels significantly

ii. Baltic Sea (receives excessive pollutants from many European countries) is highly polluted

iii. May eventually be able to use wetlands to clean wastewater (fig19-19, pg506, pg507 Solutions) b. Streams/Rivers (fig19-5, pg488) – flow fast, and can recover rapidly; waste discharge causes 4 zones:

i. Decomposition zone – after discharge, first oxygen begins to sag, types of organisms begin to decline

ii. Septic zone – oxygen is at a low, types of organisms that can survive are anaerobic only

iii. Recovery zone – dissolved oxygen begins to increase, types of organisms begin to recover

iv. Clean zone – oxygen back to normal, types of organisms back to normal c. Freshwater Lakes (pg490-491, fig 19-7) – more vulnerable to pollutants; dilution less effective than in streams b/c: lakes contain stratified layers that barely mix, have little flow; can lead bioaccumulation and biomagnification of pollutants/chemicals (like DDT, PCBs), or cultural eutrophication (see below) 5. Cultural eutrophication (pg490-491, fig19-7) – human activities greatly accelerate plant nutrients in a lake (usually b/c of nitrate- phosphates- in fertilizers, discharge from sewage treatment plants): a. Causes dense growth of algae, covers top of lake, no photosynthesis b/c plants cant get sunlight, plants die, aerobic bacteria eat the plants, bacteria use up lots of dissolved oxygen which kills fish 6. Groundwater pollution (pg493 and fig19-10) – mostly out-of-site pollution but a BIG problem b/c more than 50% of US drinking water comes from groundwater a. Comes from: landfills, deep injection wells, storage tanks (leaking gas/oil tanks), waste water lagoon b. Cant clean itself: flows slowly, has little bacteria, v. cold temperatures c. Solutions: prevention is most effective, monitor aquifers near landfills, leak detection systems, strictly regulating wastes 7. Maintaining water quality (pg509) – Key: reduce the flow of pollution into waterways, also important to monitor air pollution (accounts for 33% of water pollution): a. reduce poverty b. greater emphasis on keeping groundwater clean c. prevent non-point pollutants d. reduce toxicity/volume of pollutants e. reuse wastewater instead of discharging it f. recycling pollutants 8. water purification of drinking water (pg.509): a. In developed countries: surface water (for example, rain water) is stored in a reservoir for several days (to increase D.O. content/settle out particulates), then water is pumped to purification plant and treated to gov’t drinking water standards – run through charcoal and sand filters b. In areas with pure groundwater (and many developing countries) (pg.244 – Solutions): plastic bottle w/contaminated water in it is placed in the sun to kill pathogens (heat/UV radiation from the sun kills them) – then drink 9. sewage treatment (fig19-17 and 19-18, pg504-505) – most communities have primary/secondary only: a. Primary (mechanical process) – filters out debris through screens and by allowing it to settle out in a settling tank b. Secondary (biological process) – uses aerobic and anaerobic bacteria to remove organic wastes, includes: trickling filters, activated sludge process (where bacteria degrades wastes)

i. Combined w/primary, get out: most suspended particles, oxygen demanding wastes, toxic metal compounds, and SOME phosphates and nitrates… c. Tertiary (chemical process) – very costly, uses membranes for: reverse osmosis, microfiltration, ultrafiltration d. After the last process, water is bleached w/chlorine to disinfect and then released… 10. Septic Tank (fig 19-16, pg504) – disposes of domestic sewage: includes septic tank (traps greases/large wastes), allows the rest to filter downward (come out through percolated pipes into soil that filters it) 11. Relevant laws a. Clean Water Act – sets water quality standards b. Safe Drinking Water Act – establishes national drinking water standards (maximum containment levels) for pollutants in drinking water c. Ocean Dumping Ban (1988) – prohibits ocean dumping of sewage sludge/industrial waste d. London Dumping Convention of 1972 – 100 countries agreed not to dump highly toxic pollutants, high-level radioactive wastes into open ocean (Soviet Union did not follow through) iv. Solid and Hazardous Waste 1. Types (pg526-527): Hazardous waste is any discarded solid/liquid material that (1)contains one or more of 39 toxic carcinogenic, mutagenic compounds at levels exceeding established limits, (2) catches fire easily, (3) is reactive, (4) can corrode metal containers a. Includes: cleaning products (disinfectants/cleaners), paint/building materials, pesticides/weed killers, automobile products (gas, antifreeze, motor oil), etc b. Major ones include(pg547-552): Lead (neurotoxin – found in old paint and leaded gas); Mercury (neurotoxin – mainly from bioaccumulation/biomagnification in fish); Chlorine (bad for stratospheric ozone and human health – caused by paper and pulp bleaching); Dioxins (chlorinated hydrocarbons from industrial processes – TCDD is most toxic and very persistent) c. Comes from:

i. 75% comes from mining (smelting waste), oil and gas production ii. 13% from agricultural iii. 9.5% from industry iv. 1.5% is municipal solid waste (garbage) v. 1% is sewage sludge 2. Treatment/disposal of solid/hazardous wastes (pg542-247): a. Bioremediation – using microorganisms and enzymes to convert hazardous substances to harmless compounds – works well with organic wastes only (inexpensive, but can take a long time) b. Phytoremediation- using natural plants (poplar, sunflower, clover, mustard) to filter/remove contaminants – effective on pesticides, radioactive metals, and toxic metals (lead, mercury) c. Incineration – burn waste, can reduce trash volume, but greatly increases air pollution (dioxins) d. Landfills (*most used currently) – lined landfills in which to dump waste, later covered w/clay, plastic, sand and monitored to prevent leaking – can lead to groundwater pollution if get leaking i. Hazardous waste can be stored in above ground building (fig21-17, pg547) build of reinforced concrete that can be monitored for leaks e. Exporting waste to other countries (usually developing countries) – often then not disposed of legally… 3. Reduction – best solution is always prevention (reducing the amount of waste by consuming less); second best = reuse (glass bottles, food containers, etc), then recycle (glass, metal, plastic) 4. Cleanup of contaminated sites – want polluter pays principle 5. Biomagnification (fig11-14, pg231) – as toxic substance goes up in a food chain, the amount present in the organism increases, becomes more harmful 6. Relevant laws (pg552-553): a. Federal Insecticide, Fungicide, Rodenticide Act (FIFRA) – regulate use of pesticides b. Federal Food, Drug, and Cosmetics Act (FFDCA) – tolerance level for toxic residues in food, drugs, cosmetics c. CERCLA (Superfund Act) – trust fund for cleaning up hazardous waste sites b. Impacts on the Environment and Human Health i. Hazards to human health 1. Environmental Risk analysis (pg245 and fig11-15) – a. Four parts: identifies hazards and evaluating associated risks(risk assessment); ranking risks (comparative risk analysis); determines options and making decisions about reducing risks (risk management); inform decision makers/public about risk (risk communication)

i. Experts and public have very different views of the greatest risks: Experts say indoor/outdoor air pollution, drinking water pollution, global climate change, ozone depletion; Public says hazardous waste sites, oil spills… b. Greatest # of deaths/year is POVERTY; then voluntary lifestyle choices (ex: smoking), then pneumonia/flu, air pollution, AIDS, diarrhea, etc. 2. Acute effects (pg230) – immediate or rapid harmful reaction to an exposure (ex: dizziness, rash, or even death) 3. Chronic Effects (pg230) – permanent or long-lasting consequences of exposure to a harmful substance (ex: kidney or liver damage) 4. Dose-response relationships (pg231-232, fig11-5):

a. LD50 (median lethal dose) – amount of chemical received in one dose that kills exactly 50% of the animals in a test population within a 14 day period b. Graphed in a dose-effect curve: dose on x-axis; effect on y-axis

i. Can be threshold (a threshold must be reached before harmful effects can be felt) or non-threshold (ANY dose can be harmful) response *often non- threshold is assumed

ii. Can be linear of non-linear 5. air pollutants – lung irritation, breathing problems, and lung cancers 6. Smoking (case study, pg228) – single most preventable major cause of death/suffering among adults. ii. Hazardous chemical and the environment (pg249) – toxic chemicals are responsible for 2-4% of cancer death in US; difficult to judge exactly the damage which is why environmentalists think precautionary principle is best – pollution prevention 1. Types of hazardous waste – (Table 21-1, pg.527) any discarded solid or liquid material that (1) contains one or more of 39 toxic, carcinogenic, mutagenic, or teratogenic compounds at levels that exceed established limits (includes solvents, pesticides), (2) is flammable (gasoline, paints, solvents), (3) is reactive/unstable (acids, bases, chlorine bleach, ammonia), (4) corrodes metal containers (drain cleaners, industrial cleaners) a. See Table 11-1, pg.232:

i. Supertoxic – Nerve gas, botulism toxin, dioxins (TCDD) – LD50 dose < 0.01 mg/Kg

ii. Extremely toxic – Potassium cyanide, heroin, atrophine, nicotine – LD50 dose < 5 mg/Kg

iii. Very toxic – mercury salts, morphine, codeine – LD50 dose = 5-50 mg/Kg iv. Toxic – Lead salts, DDT, sulfuric acid – LD50 dose = 50-500 mg/Kg b. Specific hazardous materials: i. Lead: toxic neurotoxin that can harm the nervous system of young children and babies – caused by lead-based paints/leaded gasoline (both of which have now been banned in the US – but not other countries)

ii. Mercury: potent neurotoxin that can harm brain/spinal cord – comes from waste incineration, coal burning – often humans are exposed because of biomagnification/bioaccumulation from fish

iii. Dioxins – carcinogen - unwanted by-product of industrial processes (incineration of municipal and medical wastes – involving chlorine and hydrocarbons) – TCDD is most toxic, found in food supply 2. Treatment/disposal of hazardous waste (pg.542-547) a. Bioredemiation – using microorganisms to help convert toxic compounds into harmless ones; works well on organic wastes (like pesticides/gasoline) – inexpensive, but can take a while to have an effect/has to be under perfect conditions for the microorganisms b. Phytoremediation – using plants (such as: poplar, sunflower, clover) to filter/remove contaminants - inexpensive, but often slow, and might make the plant toxic if lots of pollutants c. Incineration – burning the trash in mass-burn incinerators, converts to energy – but high cost, health threat to people living in the area d. Burying – clay and plastic lined landfills that are monitored for groundwater contamination, waste is compacted and covered daily – (pg.544, fig 21-12) and secure hazardous waste landfills which have the wastes in drums with the other measures of precaution as well (pg.546, fig 21-16)

i. About 86% of landfills leak ii. Could also have above ground storage – on second floor of facility with the first floor monitored for leaks (pg. 547, fig 21-17) e. Exporting – legally (or illegally) shipping hazardous wastes to other countries – ex: Canada receives US hazardous wastes because they have less restrictive regulations 3. Cleanup of contaminated sites a. Bioremediation/phytoremediation (see above) b. Cleanup of brownfields (abandoned industrial/commercial sites that were contaminated) so that they can be used as parks/recreational areas (Congress has enacted laws that limit liability of those who redevelop the area) – pg.553 4. Biomagnification – the levels of toxins in the environment are magnified as they pass through food chains and food webs, the higher something is in the food chain, the more it will be harmed by the toxins (ex: DDT – see pg.231, fig 11-4) 5. Relevant laws a. CERCLA (pg.552) – Comprehensive Environmental Response, Compensation, and Liability Act (Superfund Act) – 1980 – follows the “polluter-pays-principle” - came about after the Love Canal disaster, taxes chemical raw materials to provide a trust fund to identify abandoned hazardous waste dump and leaking sites, then protect/clean up those sites and the groundwater around them (if the original polluter can’t be found) b. RCRA (pg.552) - Resource Conservation and Recovery Act (1976) – requires EPA to identify hazardous waste and set management standards, makes firms that handle more than 220 pounds of hazardous waste/month to have a permit, has a cradle-to- grave system to keep track of waste through its entire lifetime c. Basel Convention on Hazardous Waste – 1989 – requires exporters to get approval from recipient nation before hazardous wastes can be shipped – in 1995, strengthened to ban hazardous wastes from being shipped from developed to developing countries c. Economic Impacts i. Cost-benefit analysis (fig11-16, pg247) – asks if risk is acceptable, it is IF benefits outweigh the costs (environmentalists ask us to factor in life-cycle cost) ii. Externalities – what effects do the people who pollute have on the rest of the people who have to deal with the pollution is a negative externality: pollution, generated by a company, effects the public - who have no choice (about whether to pollute or not) and were probably not taken into account when the polluter decided to pollute iii. Marginal costs – how much will one more unit of pollution cost the public iv. Sustainability – environmentalists think the proper question is a prevention approach – what does the least damage: “Which alternatives will bring sufficient benefits and minimize damage to humans and to the earth?”