EVS lecture 6 (chapter 7: waste), lecture 7 (chapter 10: air pollution), & lecture 8 (chapter 11: ozone depletion)

अब Quizwiz के साथ अपने होमवर्क और परीक्षाओं को एस करें!

all "hazards" are not created equal

L6 "toxic" and "hazardous" waste are not synonymous - toxic: has the potential to cause injury to living organisms. almost any substance is toxic if the concentration is high enough or an organism is exposed long enough. toxins can be poisonous and harmful at low doses - hazardous: there is a chance that an organism will be exposed to a substance and that the exposure will cause harm according to the EPA, toxic waste is only waste "that is harmful or fatal to living organisms when absorbed or ingested." hazardous waste is the lower level of potentially harmful substances, toxic is higher. hazardous waste can be, but isn't necessarily toxic; ALL TOXIC WASTE IS HAZARDOUS

change

L6 - Plastic Ocean Project: started at UNCW by UNCW staff and students - The Ocean Cleanup: started by a 15 year old Norwegian boy who was tired of waiting for adults to take action - 4Ocean: funds the removal of trash from the ocean, rivers, coastlines for every purchase from their store

human health affects of hazardous waste

L6 - acute toxicity: occurrence of serious symptoms immediately after a single exposure to a substance; a single exposure can maim or kill - chronic toxicity: delayed presentation of symptoms that occur once accumulation reaches a critical threshold after repeat exposure (bioaccumulation); may occur weeks, months, or years after initial exposure; lead is chronically toxic; longer exposure = greater health risks (especially to children); rises include behavioral disorders, hearing problems, brain damage, and death

affect of hazardous substances on longterm health

L6 - carcinogenic: cause cancer in humans and animals - infections: contain disease-causing organisms - teratogenic: affect the fetus; cause birth defects or spontaneous abortions or otherwise damage the fetus - mutagenic: cause genetic changes or mutations, which then appear in future generations those at greatest risk: the poor and people with little political clout, migrant laborers who work in fields sprayed with pesticides, factory workers who are exposed to low levels of toxic heavy metals over a prolonged period of time, residents of inner cities who live in old apartments containing lead-based paint and asbestos insulation, and residents of poor rural areas afflicted with poor air quality from hog-farms, paper mills and wood pellet manufacturing facilities, sand mines and cement plants

dangers of all waste

L6 - climate change: everything releases carbon and other greenhouse gases into the atmosphere while decomposing, so that is just one way that waste contributes to climate change; landfills release large amounts of methane into the atmosphere during anaerobic decomposition, they are the 3rd larges source of methane in the US - soil quality and water quality: every day, hazardous substances such as pesticides, motor oil, mercury-containing batteries and lightbulbs, lead paint, pharmaceuticals, and toxic heavy metals from electronic components are thrown out with yesterdays newspaper and potato peels, which leach into our soils and contaminate groundwater and nearby creeks, streams, and rivers

pollution prevention and reduction solutions

L6 - individual action to reduce use of materials and conserve or prolong the lifespan of out belongings (food included) - 5 Rs: reduce, reuse, repurpose, refuse, recycle - compost - do not be victim of perceived obsolescence -- just because Apple came out with a new iPhone does not mean that your iPhone is no good -- use them until they die, then recycle or see them to a refurbishing shop - free-cycle unwanted study through Facebook Marketplace, curbside, Craig's list, nextdoor, etc. - donate to Habitat for Humanity, Salvation Army, missionary groups clothing the homeless or victims of natural and economic disasters, etc. - more and better legislation (South Korea just banned sending food to landfills -- increasing food recycling from 2 to 95%) - food waste used for livestock and pet-food trade - municipal composting - forced recycling -- the child advantage of curbside collection programs is that they usually increase the number of residents participating in a recycling effort. take it one step further and force the practice -- pay by weight of garbage, but offer free recycling - incentives for manufacturers, producers and customers - true cost pricing -- will slow down consumerism if we priced items to reflect their environmental impact

what to do with the two different waste streams

L6 - manage it: burn, bury - recover it: recycle, reuse, repurpose - prevent it: stop creating waste

legislation

L6 - three critically important federal laws that govern the release and management of waste: two concern Hazardous Waste Release (CERCLA, RCRA) and one concerns Toxic substance Production (TSCA)

hazardous waste release legislation

L6 CERCLA: - comprehensive environmental response, compensation and liability act, known as "Superfund" - enacted in 1980 - managed by EPA - NPL (national priorities list) designation to clean up hazardous sites RCRA: - resource conservation and recovery act - enacted in 1976 - established legal definition for hazardous wastes - set guidelines for managing, storing, and disposing of them in an environmental sound manner - EPA determines - "cradle-to-grave" regulation - defines hazardous waste legally (must meet one of the following categories: ignitable, corrosive, reactive, or toxic)

Rachel Carson

L6 Silent Spring (1962) rings alarm about DDT and other persistent, man-made pollutants that bioaccumulate in an individual through repeat exposure and biomagnify in the environment (soil and water and travel by air) as it is passed up the food chain

toxic substance production legislation

L6 TSCA - toxic substances control act - enacted in 1976 - regulates production, distribution, and use of chemical substances that may present an unreasonable risk of injury to human health or the environment - EPA determines and has the authority to take regulatory action to control new, potentially risky chemicals

the Stockholm Convention

L6 a global treaty that entered into force May 2004 to eliminated 12 of the most widespread and insidious POPs; a highlight is a move to embrace the "precautionary principle," which prevents and eliminated POPs at their source and allows regulatory or banning action to be taken before their is conclusive scientific proof of damaging effects

waste

L6 a human construct; it is what a person has no use for, so it varies from person to person; untapped potential, aka "unrealized resource"

solid waste

L6 any variety of materials that are rejected or discarded as being spent, useless, worthless, or in excess (refuse, trash)

teratogens

L6 anything that can cause birth defects by affecting fetal development; tobacco smokes, radiation, viruses, trauma

toxic chemicals

L6 cause either short or long term harm depending on the frequency and duration of exposure, and the chemical's damaging properties; lead, mercury and asbestos

recycling

L6 collection, processing, and marketing of waste material for use in new products aluminum uses 96% less energy to make from recycled cans than using bauxite. recycled plastic bottles use 76% less energy. newsprint uses 45% less energy. recycled glass uses 21% less energy. using raw materials is way more intensive energy-wise than recycling any product almost 70% of corrugated cardboard containers are recycled. aluminum, the most abundant metal on Earth, is never found in a free state; to be useful, it must be separated from aluminum ore (bauxite). in the US in 2001, only 21% of glass containers were recycled; nearly 90% of recycled bottles are made into new bottles. less than 10% of all plastics are recycled; not all 7 plastics are currently marketable for recycling, but all of them CAN be recycled.

waste management

L6 decomposers biodegrade (break down) organic matter into components compounds through aerobic of anaerobic decomposition - aerobic: presence. of oxygen - anaerobic: absence of oxygen *plastics are not biodegradable incineration -- burn it! - waste-to-energy municipal incinerators burn waste to produce electricity (heat and steam) - con: can release possibly harmful toxic fumes and heavy metals into the air and soil if emissions are not captured and diverted; homeowner burning has risk of fire getting out of control landfills -- sanitary and secure - con: takes up space and can leak toxic material or heavy metals into waterways and soil; produces methane in large quantities; cost of shipping waste to fills (and associated fossil fuel use to transport)

hazardous waste source reduction around the home

L6 drain cleaner - instead use a plunger glass cleaner - instead use a tablespoon of vinegar or lemon juice in water furniture polish - instead use lemon juice / vegetable oil rug deodorizer - instead sprinkle carpets with baking soda silver polish - instead use salt water and baking soda mothballs - instead use cedar chips, lavender flowers or rosemary

ocean dumping

L6 dump sewage and waste directly into waterbody (lakes, too, not just oceans) private cruise, pleasure craft and fishing boats allowed to dump (sewage sludge and industrial waste), despite the Ocean Dumping Act of 1988

pollution prevention

L6 education: you are the solution to pollution efficiency: increase resource use efficiency to reduce pollution (LED lightbulbs instead of incandescent; bamboo paper or cloth instead of tree pulp paper and cotton) precautionary principle: operate under the precautionary principle to avoid releasing pollution into he environment - source reduction - waste minimization

HAAs (hormonally active agents)

L6 environmental contaminants that act as endocrine disruptors; often chemically similar to hormones such as estrogen

precautionary principle

L6 goes along with risk assessment to decide ethically if something is safe to proceed within the absence of scientific understanding. the principle argues that the absence of scientific understanding of a new technology, substance, innovation, etc. industry and people should pause and wait for review before adopting or advancing the new item, practice, etc. the FDA operates on this premise, right? they review multiple studies before approving or denying the use of a new technology or compound. the covid vaccines have not received approval because they are still being studied, but their emergency use for humanitarian efforts has been allowed. the precautionary principle says not to approve without rigorous scientific study, but it also says that we are safer with it, than without it -- a catch 22 situation

combustible items

L6 have a strong capability of igniting or burning at normal temperatures; ethanol, solvents, and paint thinners

pollution is waste, and waste is pollution

L6 pollution is really just "matter that is out of place," EX: waste 30-40% of all food in the world ends up as waste in developed countries, loss is in retail, food service, and in home waste. in developing countries, loss is due to insufficient cold storage.

deep-well injection

L6 pumping liquid waste deep underground into permeable rock formations con: no idea if this will remain stable and not contaminate water supplies; evidence showing that this activity is increasing seismic activity in areas not accustomed or built for earthquakes

corrosive agents

L6 reactive chemicals that damage or compromise the surface of a material; sulfuric acid and battery acid

recoverable materials from the solid waste stream

L6 recoverable: there is an alternative to disposal; there is some market or personal value for that item, and it can be diverted from the waste stream - aluminum: most abundant metal on earth; never found in free state; 1.4% of total MSW; recycling aluminum instead of mining for new ore saves energy and reduces water and air pollution; larges source of aluminum waste is from cans (>66% of all cans are recycled); recycled into containers, packaging, house siding, gutters, window/door frames, and lawn furniture - paper: one of the most recycled materials; recycling paper saves trees and energy which leads to more environmentally friendly and cost-effective; recycled paper is coming from newsprint, mixed office waste, waste from paper-converting plants; newspapers are the largest single component per volume in a landfill (15-20%); 37% of newspaper is going into landfills; car manufacturers use on average 60 pounds of recycled paper per vehicle; post-consumer waste (paper that was used before being recycled); pre-consumer waste (paper that was not used before being recycled like machine trimmings and clippings); remade into cardboard products - cardboard: 70% of corrugated cardboard is recycled and sold directly to recycling mills - glass: only ~21% of glass in US is recycled; 90% of the recycled glass bottles get turned back into bottles; cullet (the crushed glass material used to produce new glass when combined with sand, soda ash, limestone and high heat); recycling glass saves energy, extends life of furnace, and reduces particulate mater emissions - plastics: made from fossil fuels, used to made from rubber and plant cellulose; highly valuable unrealized resources makes up 11.3% of MSW stream in US; less than 10% of all plastics are recycled; not all plastics are currently being recycled, although technically they all could be (it is market driven); recycled plastic can be used to make plastic lumber and fencing, flower pots, milk jugs, clothing, bathtubs, paint, automotive parts, nonfood containers, piping, traffic cones, toys, trashcans, building insulation, packaging material, and so on; made most frequently now from petroleum (oil); do not degrade by natural means; persist in the environment for hundreds and thousands of years; contain phthalates, a neurotoxin for humans that causes development problems in the reproductive system and known carcinogen (BPA); 300 million tons made annually; North Pacific Garbage patch - iron and steel: can be melted down and reformed into new iron and steel products; "tin" cans (actually most often steel); 58% of steel containers are recycled in the US - tires: 270 million tires are thrown away annually; hazardous in a landfill -- release gases and shift waste around in mound; tires can be retreaded to extend their life, which saves energy; repurposed/upcycled for use in erosion control and artificial reefs; repurposed as fuel (power plants can burn them, but they are very hazardous in terms of air pollution, and extremest volatile) - used oil: motor oil is about 60% of all used oil, the other 40% is industrial; 67% of used oil in the US is recycled into fuel, the rest is dumped in landfills or in storm sewers, which is a significant threat to water quality and wildlife

how to deal with waste

L6 reduce, reuse, recycle, repurpose, refuse

garbage

L6 refers strictly to animal or vegetable wastes resulting from the handling, storage, preparation, or consumption of food

municipal solid waste (MSW)

L6 refers to all solid waste originating from homes, industries, demolitions, land clearing, and construction; it is not merely a problem of management, we must consider how it is generated and why; in the US, we produce on average 4.5 pound s of MSW per person each day -- 329,721,476 people in the US x 4.5 pounds each day = 1.484 billion pounds of waste per day

solid waste stream

L6 refers to the collective and continual production of all refuse; the sum of all solid wastes from all resources

hazards and human health

L6 respiratory system is our first line of defense; mucus in the nose and elsewhere traps and dislodges dust and other PM pollutants trachea is lines with hair-like cilia that sweep out irritants and impurities to protect the lungs when pollutants overwhelm our systems, infections occur, leading to bronchitis and possibly pneumonia in the lungs --> bronchitis, or chronic bronchitis can lead to emphysema, asthma, chronic pulmonary disease, mesothelioma, and lung cancer

two types of landfills

L6 sanitary: municipal refuse and nonhazardous industrial wastes (EPA regulations) are dumped in landfill cells with a non-permeable liner at the base and sides to prevent leachate from entering soil or water resources secure: hazardous waste facilities; specially engineered to prevent escape of leachate into surrounding environment; lined with non-permeable materials to prevent leachate from entering soil or water resources; waste is separated by type and stored in separate compartments to prevent chemical reactions; requires detailed record keeping of what and how much waste is accepted and stored

hazardous waste

L6 solid or liquid wastes that can adversely affect human health and the environment; includes elements such as lead, compounds such as polychlorinated biphenyls (PCBs), and the products of infectious agents like bacteria and protozoa - ignitable: easily combustable/flammable during routine handling (paint, gasoline) - corrosive: dissolve steel or burns skin (battery acid, rust remover) - reactive: unstable under normal conditions and will violently react with other substances like water (bleach) - toxic: contains heavy metal, pesticides or other compounds above maximum concentrations

POPs (persistent organic pollutants)

L6 synthetic compounds that are highly toxic, very stable, and soluble in fats and oils; they are also easily dispersed; pops can have devastating, long-lasting, and far-spread environmental impacts even if released to the environment at extremely low levels; short-term exposure to high levels of a pop can be fatal or result in serious injury or illness, including damage to the liver or nervous system; chronic exposure to lower doses can be very harmful

resource recovery

L6 taking useful materials or energy out of the waste stream at any stage before ultimate disposal - recycling - composting - repurposing (up cycling)

commodity chain analysis

L6 the start to finish road of product creation also referred to as the energy life cycle or product lifecycle environmental economists perform LCA (life cycle analyses) to determine the carbon or water footprint of an item or service

US MSW by the numbers

L6 ~3% of the US' solid waste stream is made up of MSW. paper and paperboard account for the largest portion (52%) of MSW by weight. - yard waste: just over 12% - food waste: nearly 12% - plastics: 11.3% - metals: 8% - glass: 5.3% - wood: 5.8% 2018 US figures (from EPA): - 4.9 pounds per person per day - total of 292.4 million tons in 2018 - 50% was landfilled, 12% waste-to-energy, 32% recycled or composted, 6% "other"

volatile organic compounds (VOCs)

L7 - a primary pollutant - hydrocarbons and other organic chemicals * generally oxidized to CO and CO2 * natural emission: plants and fires * anthropogenic: fossil fuels use and industrial processes and products EXAMPLES: 400 million tons of methane produced by natural wetlands and rice paddies benzene, formaldehyde, solvents, gasoline, toluene, perchloroethylene, adhesives, cleaners, paints and lacquers, fire retardants, packing peanuts

cap and trade

L7 - acid rain program is a market-based cap and trade approach to emissions reduction - cap and trade programs, begun in 1990, set maximum amounts for pollutants, but let facilities facing costly cleanup pay others with lower costs to reduce emissions on their behalf *has worked well for sulfur dioxide, but set no limits on NOx *however, it permits local hot spots where high polluters continue to pollute, because they are paying someone somewhere else to reduce pollution

air pollution

L7 - any substance present in or released to the atmosphere that adversely affects environmental or human health point source: emitted from stationary sources like industrial smokestacks or power plants non-point source: moving sources like motor vehicles non-attainment: failing to meet EPA air quality standards (NAAQ standards) types of air pollution: natural vs anthropogenic, primary vs secondary, criteria pollutants

areas most sensitive to acid

L7 - areas with low pH soils are sensitive - areas that have reduced buffering potential because of years of acid rain - soils that contain calcium carbonate (CaCO3) have good buffering capacity (calcium carbonate.. Tums)

clean air legislation

L7 - clean air act (1963): first national air pollution control - clean air act (1970) (extensively revised over time): identified the 6 critical pollutants; established ambient air quality standards - 1990 amendments addressed: acid precipitation, urban air pollution, toxic emissions, ozone depletion - Source review in 1977 allowed old plants to be grandfathered in, but required new equipment to meet air pollution standards.• *Result was that companies kept old facilities operating in order to avoid pollution controls *Forty years later, these old plants (often expanded in size) continue to be among biggest contributors to smog/acid rain - Despite disputes, CAA has been successful in saving money and lives.

national ambient air quality standards (NAAQS)

L7 - established by clean air act - 1970, amended in 1990 - enforced by EPA - primary standards: set limits on pollutants in order to protect public health, especially the health of sensitive population such as children, the elderly, and those that suffer from asthma - secondary standards: have limits that protect public welfare, things like protection against decreased visibility, damage to crops, and vegetation - rank air quality based on standards for 6 criteria pollutants

climate and topography influence pollution

L7 - in normal circumstances, air temperature decreases as altitude increase (it get colder as you go up in the atmosphere) - climate, location and topography can influence and alter normal temperature stratification and lead to a temperature inversion - coastal, valley and basin communities see naturally occurring inversions daily or seasonally, in times of rapid cooling - inversions: temperature inversions occur when a stable layer of warm air lies above cooler air, reversing the normal temperature decline with increasing height, and prevents convection currents from dispersing pollutants * rapid nighttime cooling in a basin as the cold air becomes trapped

long-range transport

L7 - soil erosion causes dust and sand storms that put PM into the air - dust can travel thousands of KM. dust from the Sahara regularly ends up in Miami, Florida, for example New Delhi, India is the most polluted metropolis in the world and covered in thick toxic clouds daily but worsens in colder fall and winter months, causing 2 million deaths/year. this cloud is disrupting monsoon rains on which harvests in South Asia depend, like it did pre-French Revolution!

four processes affect air pollution levels

L7 1. emissions - sources can be both human-made and natural 2. chemistry - chemical reactions create and destroy pollutants 3. transport - advection winds transport pollutants 4. deposition - receptor sites - dry or wet (acid precipitation)

grasshopper transport

L7 Hazardous Air Pollutants (HAP) that degrade slowly and remain volatile (reactive) travel great distances to settle in the poles in a multi-deposition journey. 'Jumping' like grasshoppers, these compounds are emitted in warmer regions (where people and industry are) and reach the poles through repeated processes of evaporation and deposition, where they condense and accumulate in cold waters or ice. Contaminants bioaccumulate in food webs; this is why we see dangerously high levels of HAPs in whales, polar bears, & deep-water polar wildlife.

criteria pollutants

L7 US clean air act designated six major criteria pollutants for which maximum ambient air levels are mandated (regulated): - sulfur dioxide - nitrogen oxides - ozone - lead - carbon monoxide - particulates VOCs are primarily pollutant, but not necessarily a criteria pollutant nitrogen oxides (NOx) - natural sources: formed at high temperatures during lightening strikes, or when N compounds are oxidized by bacteria - anthropogenic sources: combustion of fossil fuels, motor vehicles, agriculture/fertilizers, wastewater management, industry - NO is further oxidized to give nitrogen dioxide (NO2) the reddish brown gas in smog - NO is an important greenhouse gas - NOx combines with water to make the nitric acid found in acid precipitation (along with sulfuric acid) - humans are responsible for 60% of NOx of emissions sulfur dioxide (SO2) - natural sources: evaporation from sea spray, volcanic fumes, and organic compounds - anthropogenic sulfur: SO2 from fossil-fuel (COAL) combustion, oil refining, and smelting of sulfide ores (metals) - SO2 is a corrosive gas which reacts with water vapor in the air to cause acid precipitation - 2/3 of total sulfur influx is anthropogenic - is emitted from aerosols - only criteria pollutant that is NOT emitted from transpiration sector lead - natural sources: geological deposits, trace amounts in plants, animals, air, water, dust, soil - anthropogenic sources: fuel (especially coal), turned into pipes, jewelry, tableware, pigments, batteries - lead makes up 2/3 of all metallic air pollution - a neurotoxin that bioaccumulates permanently in bone - banning lead from gasoline (19990/1995) was one of the most successful pollution controls in American history - since the ban, children's average blood levels have dropped 90% and average IQ has risen 3 points - regulations (slide 22 lecture 7) particulate matter (PM) - aerosol - solid particles or liquid droplets suspended in the atmosphere - atmospheric aerosols are called particulate matter PM - primary aerosols: dust, soot, ash smoke, lint, pollen, spores etc. - secondary aerosols: form by condensation of industrial vapors - aerosols reduce visibility and are hazardous to human health - anything smaller than 10 micrometers can be inhaled - when smaller than2.5, but smaller than 10 micrometers can enter airways, but typically get coughed out before settling and causing damage - controlled by the EPA and Clean Air Act. EX: asbestos and cigarette smoke cause cancer - scientific research into the negative health effects of fine particulate air pollution spawned strict EPA regulations. PM10 rule: emissions of particles with diameter of 10 mm cannot exceed 150 ug/m3 in 24 hours. PM2.5 rule: particles with diameter of 2.5 mm (or smaller) cannot exceed 35 ug/m3 in 24 hours - coarse particulate matter (PM10) are 2.5 to 10 micrometers in diameter. sources include crushing or grinding operations and dust stirred up by vehicles on roads - fine particulate matter (PM2.5) are 2.5 micrometers in diameter or smaller and can only be seen with an electron microscope. fine particles are produced from all types of combustion, including motor vehicles, power plants, residential wood burning, and some industrial processes carbon monoxide (CO) - a colorless, odorless, toxic gas; deadly to humans - inhibits respiration by binding irreversibly to hemoglobin in the blood - natural sources: rock and minerals, living organisms - anthropogenic sources: produce by incomplete fuel combustion - largest proportion produced by vehicles; also biomass burning, industrial processes - predominant form of C in the air is CO, with levels increasing due to use of fossil fuels - major contributing factor to global warming - stages of CO exposure: headaches, nausea, dizziness, breathlessness, collapse, loss of consciousness ozone (O3) - layer in the stratosphere shields the biosphere by absorbing incoming UV radiation (UV-C is most dangerous) - Natural: plants and soil stratospheric ozone - anthropogenic: it is not directly emitted from any one source! It's a secondary pollutant - in the troposphere it is a pollutant: a photochemical oxidant (product of secondary atmospheric reactions driven by solar energy) *formed by the interaction of sunlight with hydrocarbons and NOx emitted by vehicles, gasoline vapors, fossil fuel power plants, refineries, and other industries - has an acrid, biting odor that is a characteristic photochemical smog - damages vegetation and buildings

unconventional pollutants

L7 aesthetic degradation: reduce quality of life by increasing stress and disrupting sleep - noise - odor - heat - light pollution - prevents us from seeing stars (a serious problem for astronomers) and maritime travelers - can confuse wildlife (birds and sea turtles most notably) light and heat pollution indoor air pollution - EPA found indoor concentrations of toxic air pollutants are often higher than outdoor - people generally spend more time indoors - VOCs from formaldehyde, chloroform, benzene, and other chemicals in carpeting, paints & varnishes, and furniture in homes can be found at concentrations that would be illegal in the workplace mercury - a teratogen that interferes with neurological development - accumulates in aquatic food chain *biomagnifies: increased concentration of a contaminate with increasing trophic level *bioaccumulates: concentration of contaminate in muscle and tissues increases with increasing body size, age, and trophic level - mercury poisoning: low doses can cause brain damage, nervous system damage, fetal development issues and cognitive impairments *natural sources: volcanic eruptions, weathering of rocks, undersea or geothermal vents *anthropogenic sources: gold production, non-ferrous metal production, incinerators, cement production, coal-burning *pre-industrial revolution concentrations were 3 to 4-fold lower and in some places, 11-fold lower acid deposition: wet solutions or dry acidic particles deposited on land and water from the air - H2SO4 ((sulfuric acid) and HNO3 (nitric acid) deposition *industrial coal use = SO2 emission *automobile emissions = NOx emission - deposition occurs within 4-14 days downwind from source

air quality index (AQI)

L7 divided into six categories: 0-50: good, green 51-100: moderate, yellow 101-150: unhealthy for sensitive groups, orange 151-200: unhealthy, red 201-300: very unhealthy, purple 301-500: hazardous, maroon

waldsterben

L7 forest death

effects of air pollution

L7 human health - world health organization (WHO) estimates each year 5-6 million people die prematurely from illnesses related to air pollution. likelihood of suffering ill health is related to intensity and duration of exposure. as much as a 5-to-10 year decrease in life expectancy if you live in the worst parts of LA PM2.5 - particulates less than 2.5 micron in diameter are particularly risky and have been linked with heart attack, asthma, lung cancer, and abnormal fetal development - new rules will remove particulates from Diesel engines and power plants - most air pollutants are inhaled, but some can be directly absorbed through the skin or ingested in food and water solutions? reduce emissions - voluntary actions - mandated regulations (EPS's 1986 TRI - Toxic Release Inventory) *covers 188 chemicals and requires industry to report how much of each toxin they release to air, water, land, sewers and injection wells - technology advances to replace harmful compounds with better alternatives

secondary air pollutants

L7 many types - primary gaseous pollutants can reach with one another, water vapor, fine aerosol particles, or with VOCs EX: sulfur dioxide is oxidized into sulfuric acid which can then form an "acidic aerosol" on aerosol particles EX: ground-level ozone (O3)

sources and receptors

L7 pollutant sources can be miles away from where advective winds transport material - advective winds are prevailing winds receptor site - location of where pollution ends up EX: los angeles -- grand canyon how do we trace non-point pollutant sources? chemical "fingerprint"

anthropogenic air pollution

L7 primary pollutants - emitted directly into the atmosphere (sulfur dioxide SO2, nitrogen oxides NOx, carbon monoxide CO, volatile organic compounds VOCs) secondary pollutants - not directly emitted into the atmosphere - results of chemical reactions in the atmosphere from primary pollutants (smog, O3)

rain water vs acid precipitation

L7 pure water (pH=7) precipitation (pH=5-7 range) acid precipitation (pH=<5, less than 5) environmental indicators - acid precipitation's effects first observed in mountain lakes (Scandinavia) - aquatic effects are severe; pH of 5 in freshwater lakes disrupts animal reproduction and kills plants, insects, and invertebrates; <pH 5, adult fish die. - release of aluminum ions (Al3+) in nearby soils will asphyxiate fish by stimulating excessive mucus formation clogging gills synergistic effects - synergistic (combined) effects can occur when plants are exposed to several pollutants simultaneously (EX SO2 and O3) - at low concentrations, White Pine seedlings are not affected by either sulfur dioxide or ground-level ozone; but together they interact and cause visible leave damage

reducing air pollution

L7 reducing production - conversation: by reducing electricity consumption, insulting buildings, and providing energy saving public transportation - particulate removal remove particles physically by trapping them in a porous mesh which allows air to pass through but holds back solids *electrostatic precipitators - fly ash particles pick up electrostatic charge as they pass between large electrodes in waste stream, and accumulate on collecting plate air pollution control - sulfur removal *switch from soft coal with a high sulfur content to low sulfur coal *change to another fuel (natural gas) - nitrogen oxides *best method is to prevent creation *staged burners *selective catalysts - hydrocarbon control *use closed systems to prevent escape of fugitive emissions

temperature inversions

L7 the troposphere's temperature increases with altitude/height instead of decreases - warm air is lying over cold air - in LA and New Delhi, smog is trapped by temperature inversions. Smog is caused by car exhaust, not industrial emissions - they can happen anywhere, but bowl-like topography in coastal towns is most typically where we experience them

smog

L7 urban air pollution characterized by: - heavy concentrations of primary and secondary pollutants, particulates and vapor - 1905 Dr. Harold Antoine des Voeux coined the term by joining the words "smokey fog" - Arie Haagen-Smit discovered this reaction in 1952 the great smog - London December 5-9, 1952 - temperature inversion and deadly fog caused 4000 initial deaths due to smoke, sulfurous particles and soot. Eventually led to over 12000 deaths industrial smog - results from a reaction with the sun + industrial emissions (Sox and P) to form O3 and SO2 - grayish in color and more frequent in Northeast US and Northern Europe photochemical smog - results from a reaction with the sun + car emissions (NOx and unburned hydrocarbons) to form ground-level ozone (O3) and NO2+ visibly, damages plants, irritates eyes, and causes respiratory distress - car exhaust contains the following key ingredients of smog: - nitrogen oxides (NOx) - carbon monoxide (CO) - unburned reactive hydrocarbons (RH)

natural sources of air pollution

L7 volcanoes (ash and acidic components) sea spray (sulfur compounds) vegetation (volatile organic compounds) dust storms (particulate matter) bacterial metabolism (responsible for 2/3 of atmospheric methane)

health effects of PM

L7 people with heart or lung diseases, older adults and children are most likely to be affected by particle pollution exposure. however, even if you are healthy, you may feel temporary symptoms if you are exposed to high levels of particle pollution. numerous scientific studies connect particle pollution exposure to a variety of health issues such as - irritation of nose eyes and throat - coughing - reduced lung function - irregular heartbeat - asthma attacks - heart attacks - premature death in people with heart or lung disease

stratospheric ozone depletion

L8 - Farman published in Nature in 1985 that stratospheric O3 levels over South Pole were dropping rapidly every September and Octobe *between 1975 and 1984, they had dropped by 40% *occurring since at least 1960, he had the baseline data to establish "normal" levels of 250-350 DU *US scientists, Molina and Rowland, in 1974 proved that CFCs destroy stratospheric O3 ^won 1995 Nobel Prize in chemistry for their work on ozone, the first Noble prize in environmental science

ozone hole discovery

L8 - Joseph Farman: a meteorological technician; collected ground-level O3 readings at Halley Bay, Antarctica (British Antarctic Survey) station starting in 1957 - he was ridiculed and unsupported by BAS - NASA satellite data from the 1970s --> measurements were so low, they were discarded by computers as errors - following Farman's publication, data was reanalyzed and found to support his 1985 findings

Montreal protocol

L8 - Montreal protocol (1987) phased out use of CFCs. HCFCs were substituted, which release less chlorine - very successful - CFCs cut by 95% since 1988 - Levels should be back to normal by 2100 due to "shelf-life" of CFC-11 and CFC-12 - also contributing to the reduction of greenhouse gas emissions

polar complexities

L8 - PSC clouds absorb molecules and freeze them, concentrating them for months at a time *when sun returns in the spring, solar energy liberates the chlorine, allowing it to take an O molecule and destroying the O3 *ice crystals in this mass collect CFCs and other chemicals and set up condones for formation of chlorine monoxide (ClO), the molecule most responsible for seasonal loss of ozone

ozone and light spectrum

L8 - UV-A = 320-400 nanometer (billionth of a meter) *long-wave radiation *UV-A completely penetrates ozone layer and reaches the ground ^95% of all UV rays hitting the Earth's surface ^present at equal intensity during daylight hours throughout the year ^can penetrate clouds and glass *penetrates deep into our skin ^ages our skin--wrinkles and photo-or premature aging ^long thought to not be "too bad," but new research suggests otherwise - UV-A = 320-400 nanometer - UV-B = 280-320nm *short-wave radiation *UV-B can penetrate ozone layer and reach the ground --> Ozone blocks up to 300nm, so UV-B 300 to 320nm makes it in ^intensity varies by season, location, and time of day ^most significant from 10am to 4pm from April to October in northern hemisphere ^does not significantly penetrate glass *damages the surface of our skin, the epidermis ^causes sunburn ^major contributor to skin cancers, cataracts, suppressed immune system -UV-C = 200-280nm *short-wave radiation *completely absorbed by ozone layer *very dangerous to human health, even lethal - O3 measurements are directly related to the amount of UV light reaching Earth's surface (EX a measure of UV exposure received at the surface) *the less total O3 there is, the more UV light penetrates, hence the faster you get sunburned

costs and benefits of UV radiation

L8 - UVB stimulates vitamin D production --> healthy bones, heart disease prevention, cancer fighter, autoimmune disorders - improved mood --> seasonal affective disorder - increased energy - causes eye problems (cataracts and snow blindness) even if dark glasses are worn - suppresses immune response to herpes virus and damages in the spleen - reduces photosynthesis in plants, thereby reducing the size and yield of crops - plankton suffer damaged dna *reducing the world's populations of phytoplankton would significantly impact the world's carbon cycle, because phytoplankton store huge amounts of carbon in the ocean

what does stratospheric ozone do?

L8 - a selective gas --> absorbs only specific wavelengths of UV radiation *absorbs rays between 200nm and 300nm *the "Hartley band" (200-300nm) - ground-level (tropospheric) O3 = pollutant - stratospheric O3 = life on Earth (due to atmosphere) - 1% decrease in O3 can: *increase human skin cancer cases worldwide by 1 million/year *decrease agricultural production production *reduced ocean plankton (O2 providers and primary producers)

bromine and halons

L8 - bromine is a halogen gas *used to extinguish fires --> protection for large computers, military hardware, aircraft engines *agricultural fumigant (methyl bromide) - chlorine is about 100 times more abundant than bromine, however, bromine surpasses chlorine in its ability to destroy ozone - bromine does this because a larger fraction of bromine remains in chemical active forms (Br and BrO -- bromine monoxide) - the net effect is atom for atom, bromine is about 10x more potent than chlorine in ozone destroying ability

chlorine chemistry and activity

L8 - chlorine partitions itself into several chemical species - the most active are Cl and ClO (chlorine monoxide) - maximum ozone depletion by chlorine catalysis corresponds with high ClO concentrations chemical reaction - CFCs reach the atmosphere and react with UV light and O3 - O3 splits into O2 + O - CFC-Ozone reactions occur more frequently than ozone formation

polar stratospheric clouds (PSCs)

L8 - form at pole because of Polar Vortex super cooling the air below (-80) degrees Celsius - at these temps, chemicals freeze out as solid ice crystals - type-1 PSC = frozen nitric acid, sulfuric acid and water - type-2 PSC = water ice - type-1 PSC help activate chlorine from CFCs in the stratosphere and cause O3 depletion *the more clouds in winter, the more thinning we see

stratospheric O3 depletion

L8 - natural stratospheric ozone loss is a catalytic cycle involving NOx which speeds up ozone loss by cycling between NO and NO2, but are not consumed in the process *where is NOx coming from in troposphere? - in stratosphere, NOx is produced via an oxidation reaction when N2O emitted by bacteria at Earth's surface is photolyze by UV rays *N2O is inert in the troposphere and therefore transports to stratosphere

nitrogen oxides and ozone

L8 - nitrogen dioxide (NO2) is the main source of NOx and is analogous to CFCs in the chlorine cycle - UV radiation causes a catalytic reason with NO2 and ozone to produce NO - NO is then converted to HNO3 (nitric acid)

how do we stop ozone depletion?

L8 - phase out and ban CFCs and related chemicals - Montreal protocol international treaty

ozone depletion

L8 - the O3 "hole" is the blue area on the image on slide 11 - normal thickness is about 250-350 Dobson units (1960s readings) - 220 Dobson Units is considered "thinning" *prior to 1979, total O3 values over Antartica were never below 220 DU *from direct measurements over Antarctica, a column of O3 level of <220 DU is a result of O3 loss from chlorine and bromine compounds - record size on September 9, 2000 *11.55 million square miles (29.9 million km^2) - record thinnest on September 30, 1994 --> 73 DU - O3 depletion is most severe over Antarctica (but also observed over Arctic) - occurs annually *Antarctica: September-November *Arctic: January-March

depletion is seasonal

L8 - the one hole grows throughout the early spring (Antarctic --> September) until temperatures warm and the polar vortex weakens, ending the isolation of the air in the polar vortex - as air from the surrounding latitudes mixes into the polar region, the ozone-destroying forms of chlorine disperse. the ozone layer then stabilizes until the following spring

poles

L8 - unique atmospheric features at the poles called Polar or Circumpolar Vortices - a Polar vortex is a west-to-east swirling mass of very cold air with low [O3]. It is a winter phenomenon that builds as the sun sets and temperatures drop at het poles. polar winters isolate the mass from the rest of the atmosphere for several months. the mass extends up through the stratosphere column - the polar vortex isolates antarctic/arctic air and allows the stratosphere to drop to extremest low temperatures and form ice crystal clouds called polar stratospheric clouds

chlorine -- a continues threat

L8 even though production and use of CFCs and CCl4 was banned, they continue to be a threat because of their "atmospheric lifetime" CFC-11 (~45 to 76 years) CFC-12 (~100 to 139 years) CCl4 (~85 years)

chlorine culprits

L8 main chemicals: - CFC-11 (CFCl3) - CFC-12 (CF2Cl2) - Carbon tetrachloride (CCl4) - CFCs are inert in troposphere so they make it to stratosphere where they photolyze and release chlorine (Cl) atoms --> Cl atoms cause catalytic O3 loss by cycling with ClO - Carbon net will do the same, but is active in stratosphere as well (toxicity concerns)

main causes of ozone depletion

L8 main problem: chlorine from CFCs and carbon tetrachloride (CCl4) other chemicals: - halons (contain bromine and chlorine use in fire retardants) - methyl bromide (pesticide) - methyl chloroform and carbon tetrachloride (industrial solvents used in production of pesticides) - nitrous oxide (released from burning fossil fuels, agricultural practices (fertilizers) and naturally form bacterial decomposition

CFCs and carbon tetrachloride

L8 past uses: - refrigerators and air conditioners -- Freon - propellants in aerosol spray cans - plastic foam bubble/peanuts -- packaging - cleaner solvents for electronic parts (computer chips) and cleaning industry - inhalers -- still approved propellant - fire retardants research finds CFCs harmful - 1973: Molina and Rowland from the University of California at Irvine found CFC as cause of O3 depletion *first discovery that O3 thinning was observed at greater rates than caused naturally - 1978: US government banned aerosols containing CFCs, but American production of CFCs was still permitted for refrigeration and other uses - 1988: DuPont acknowledged CFCs as cause of O3 depletion - 1995: Nobel Prize in Chemistry goes to Mario Molina, F. Sherwood Rowland and Paul Crutzen

stratospheric O3 formation

L8 stratospheric ozone is formed by a photolytic reaction with O2. Strong UV photons are needed for photolysis to occur, so this cannot happen in troposphere due to the absorption of long-wave rays in stratosphere. O2 + UV --> O + O O + O2 --> O3 ozone levels in the stratosphere are 10x - 100x higher than what one experiences at Earth's surface in the worst smog events. ozone photolyzes (reacts with the sun's UV energy) to release O2 and O, but this is not an actual sink since O2 and O can just recombine to ozone. O3 + UV --> O2 + O


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