Unit VI: Pollution
Urban heat islands and rainfall
Since warmer air can hold more water vapor, rainfall can be as much as 30% greater downwind of cities when compared with areas upwind.
Cultural eutrophication: phosphates
a component of inorganic fertilizers. not water soluble like nitrates. adhere to soil particles. soil erosion contributes to the buildup of phosphates in water supplies. phosphates are most damaging in freshwater systems.
Bacteria and methyl mercury
bacteria that process sulfate (SO4 2-) in the environment take up mercury in its inorganic form, and through metabolic processes convert it to methyl mercury. methyl mercury is much more toxic than inorganic mercury. organisms require considerably longer to eliminate methyl mercury than elemental mercury.
the effects of oil spills on marine plants and phytoplankton
because oil floats on top of water, less sunlight penetrates into the water, limiting the photosynthesis of marine plants and phytoplankton and affecting the food web in the ecosystem.
Acid deposition due to nitrogen oxides (NOx)
begins with nitrogen oxides formed by burning oil, coal, or natural gas. nitrogen oxides also found in volcanic vent gases and formed by forest fires, bacterial action in soil, and lightning-induced atmospheric reactions. nitrogen monoxide/nitric oxide (NO) reacted with oxygen gas to produce nitrogen dioxide gas (NO2). Finally, nitrogen dioxide reacts with water vapor in the atmosphere to produce nitrous and nitric acids. (HNO2 and HNO3)
Acid deposition due to sulfur dioxide (SO2)
begins with sulfur dioxide being introduced into the atmosphere by burning coal and oil, smelting metals, organic decay, and ocean spray. It then combines with water vapor to form sulfurous acid (H2SO3). Finally, the sulfurous acid reacts with oxygen to form sulfuric acid (H2SO4)
Sewage Treatment/Septic Systems: secondary treatment
biological treatment. is designed to degrade substantially the biological content of the sewage derived from human waste, food waste, soaps, and detergent. specific steps include filters, activated sludge, filter (oxidizing) beds, trickling filter beds using plastic media, and secondary sedimentation.
Most dead zones occur in
bottom and near-bottom water near inhabited coastlines, where aquatic life is most concentrated.
Formation of Industrial Smog: Carbon in coal or oil is burned
burned in the presence of oxygen gas to produce carbon dioxide and carbon monoxide gas. C + O2 --> CO2; C + O2 --> CO
Acid deposition: acid shock
caused by the rapid melting of snow pack that contains dry acidic particles. results in acid concentrations in lakes and streams 5 to 10 times higher than acidic rainfall.
What results from O3?
causes lung irritation and damage, bronchial constriction, coughing, wheezing, and eye irritation. damages plants, rubber, and plastics.
What results from VOCs?
causes respiratory irritation and damage. most are carcinogenic and cause liver, kidney, and central nervous system damage.
Peroxyacyl nitrates (PANs) chemical equation
hydrocarbons + O2 + NO2 + light --> CH3COOONO2 (PAN)
Volatile Organic Compounds (VOCs)
include organic compounds that have a high vapor pressure (easily evaporate)
Water pollution: Air pollution
pollutants like mercury, SO2, NO, and NH3 fall out of the air and into the water. can cause mercury contamination in fish and acidification and eutrophication of lakes. the oceans have already absorbed enough CO2 to have already caused a slight increase in ocean acidification.
New evidence strongly suggests that components of crude oil called ______ persist in the marine environment for years and are toxic to marine life at concentrations in the low parts per billion range.
polycyclic aromatic hydrocarbons (PAHs)
PANs decomposition rate
since they decompose quite slowly in the atmosphere, PANs are able to transport these unstable compounds far away from urban and industrial origin. PANs transport NOx to regions where it can more efficiently produce ozone.
Suspended Particulate Matter (PM10) 4 examples
smoke, dust, diesel soot, and asbestos.
Noise regulation by governmental agencies effectively began in the U.S. with
the 1972 Federal Noise Control Act
Significant decreases in concentrations and emissions of SO2 concentration in the U.S. reflect the success of
the Acid Rain Program and the Clean Air Act
Chronic exposure to PAHs can affect
the development of marine organisms, increase susceptibility to disease, and jeopardize normal reproductive cycles in many marine species.
Water pollution: plastic: macroscopic level
the physical size of the plastic kills birds and turtles as the animals' digestion cannot break down the plastic inside their stomachs. also makes it much more difficult for animals to see and detect their normal sources of food through the water column.
Cultural eutrophication
the process whereby human activity increases the amount of nutrients entering surface waters. mostly nitrates (NO3 -) and phosphates (PO4 3-) that come from fertilizer, sewage discharge, and animal wastes.
4 methods for cleaning up oil spills
the use of microorganisms to break down oil; chemical agents, dispersants, sorbents, and detergents that act to disperse the oil, absorb it, or cause it to clump into gel-like agglomerations that sink. controlled burning. booming, skimming, and/or vacuuming the oil from the surface or shoreline.
5 examples of VOCs
toluene, xylene, formaldehyde, benzene, and acetone.
Noise pollution
unwanted human-created sound that disrupts the environment. dominant form is from transportation sources, primarily motor vehicles, aircraft noise, and rail transport noise.
The heat island effect can be slightly reduced by
using white or reflective building materials and increasing the amount of landscaping and parks.
Groundwater pollution
waste solvents, heavy metals, and radioactive materials are injected directly into deep groundwater via thousands of injection wells. water entering an aquifer remains there for 1,400 years. once an aquifer is contaminated, it is practically impossible to remove the pollutants.
Studies show that up to % of drug prescriptions pass through the human body unaltered.
90%
A near permanent temperature inversion occurs over
Antarctica.
Explain the relationship between biodegradable waste, microorganisms, and oxygen
Biodegradable wastes are used as nutrients by bacteria and other microorganisms. Excessive biodegradable wastes can cause oxygen depletion in receiving waters. This can result in increases in anaerobic bacteria that produce ammonia, sulfides, and methane and decreases of aerobic organisms like fish.
Water pollution: plastic: invasive species
Marine plastics facilitate the spread of invasive species that attach to floating plastic in one region and drift long distances to colonize other ecosystems.
Formation of photochemical smog net result
NO + VOCs + O2 + uv --> O3 + PANs
How is ozone (O3) formed?
formed by sunlight reacting with nitrogen oxides (NOx) and volatile compounds (VOCs) in the air.
how is NO2 formed?
forms when fuels are burned at high temperatures. also results from forest fires, volcanoes, lightning, and bacterial action in soil.
Where are a lot of VOCs found?
found in paints, aerosol sprays, dry-cleaning fluids, and industrial solvents
SBS is frequently pinned down to flaws in
heating, ventilation, and air conditioning systems
Sewage Treatment/Septic Systems: primary treatment
physical treatment. is to reduce oils, grease, fats, sand, grit, and coarse solids. specific steps include sand catchers, screens, and sedimentation
Water pollution: nutrients
phosphorus and nitrogen are necessary for plant growth and are plentiful in untreated wastewater. when added to lakes and streams, they can cause the growth of aquatic weeds that block waterways as well as algal blooms. if the source is from humans, it is called cultural eutrophication.
Formation of Industrial Smog: unburned carbon
ends up as soot or particulate matter (PM). C
4 ways mining contributes to water pollution
1) The mining process exposes heavy metals and sulfur compounds that were previously locked away in the Earth. rainwater leaches these compounds out of the exposed Earth, resulting in acid mine drainage and heavy-metal pollution that can continue long after the mining operations have ceased. 2) the action of rainwater on piles of mining waste (tailings) transfers pollution to freshwater supplies. 3) huge pools of mining waste slurry are often stored behind containment dams that often leak or infiltrate ground water supplies 4) mining companies in developing countries often dump mining waste directly into rivers or other bodies of water as a method of disposal
Sewage Treatment/Septic Systems: 3 stages of wastewater treatment
1) a septic system consists of a tank and a drain field. wastewater enters the tank, where solids settle. 2) anaerobic digestion using bacteria treats the settled solids and reduces their volume 3) excess liquid leaves the tank and moves through a pipe with holes in it to a leach field where the water then percolates into the soil.
Algal bloom 4 steps
1) increased algae due to increased nitrate and/or phosphate concentrations result in decreased light penetration and killing off of deeper plants and their supply of oxygen to water 2) oxygen concentration decreases in the water due to the consequences of increased material for decomposers (more algae to break down) 3) lower oxygen concentrations cause fish and other aquatic organisms to die and contaminate the water at a high rate 4) decaying fish and algae produce toxins in the water
4 secondary pollutants
1) sulfur trioxide (SO3) 2) sulfuric acid (H2SO4) 3) ozone (O3) 4) chemicals found in photochemical smog such as PANS (peroxyacyl nitrates)
6 primary pollutants
1) suspended particulate matter or soot (PM10) 2) nitrogen monoxide/nitric oxide (NO) 3) nitrogen dioxide (NO2) 4) sulfur dioxide (SO2) 5) carbon dioxide (CO2) 6) carbon monoxide (CO)
Reduction in Suspended Particulate Matter (PM10) would produce health benefits of
10 times greater than similar reductions in all other air pollutants combined.
What secondary pollutant forms from NO2?
Forms nitric acid (HNO3) in the air and contributes to acid deposition and cultural eutrophication.
Water pollution: Noise pollution
Many marine organisms, including marine mammals, sea turtles, and fish, use sound to communicate, navigate and hunt. because of oceanic water noise pollution caused by commercial shipping, military sonar, and recreational boating, some species may have a harder time hunting or detecting predators. they may also not be able to navigate properly.
What results from PANs?
PANs transport NOx to regions where it can more efficiently produce ozone. At concentrations of only a few parts per billion, they cause eye irritation. At higher concentrations, they cause extensive damage to vegetation.
Suspended Particulate Matter (PM10) size
PM10s are particles with a diameter of 1/7 the width of a human hair or less (less than 10 micrometer)
the effects of oil spills on marine life
The oil penetrates the feathers of seabirds, reducing the feathers' insulating ability and making the birds more vulnerable to temp. fluctuations and much less buoyant in the water. As birds preen (clean their feathers with their beaks), they ingest the oil --> kidney and liver damage --> dehydration. Note: marine mammals exposed to oil spills are affected in similar ways as seabirds.
Water pollution: suspended matter: deforestation
When forests are clear-cut, the root systems that previously held soil in place die and the sediment is free to run off into nearby streams, rivers, and lakes.
Water pollution: plastic: The Great Pacific Garbage Patch/Pacific Trash Vortex
a large system of rotating ocean currents (gyres) of marine litter in the central North Pacific Ocean. characterized by high concentrations of floating plastics, chemical sludge, and other debris that have been trapped by currents of the North Pacific Gyre. formed gradually as a result of marine pollution. the gyre's rotational pattern draws in waste material from across the North Pacific Ocean, including coastal waters off North America and Japan. As material is captured in the currents, wind-driven surface currents gradually move floating debris toward the center, trapping it in the region.
criteria air pollutants
a set of air pollutants that cause smog, acid rain, and other health hazards and are typically emitted from many sources in industry, mining, transportation, power generation, and agriculture. in most cases they are the products of the combustion of fossil fuels or industrial processes
Indoor air pollution (sick building syndrome)
a term used to describe a combination of ailments associated with an individual's place of work or residence. the most common pollutants found indoors include molds, bacteria, carbon monoxide, radon, allergens, asbestos, tobacco smoke, and formaldehyde and other VOCs released from carpeting, adhesives, and particleboard.
catalytic converter "three way" converter
a) Reduction of nitrogen oxides to nitrogen and oxygen b) oxidation of carbon monoxide to carbon dioxide c) oxidation of unburned hydrocarbons to carbon dioxide and water.
catalytic converter
an exhaust emission control device that converts toxic chemicals in the exhaust of an internal combustion engine into less noxious substances. most present-day vehicles that run on gasoline are fitted with a "three way" converter, since it converts the three main pollutants: nitrogen oxides, carbon monoxide, and hydrocarbons
the EPA has stated that catalytic converters
are a significant and growing cause of global warming, because of their release of nitrous oxide (N2O), a greenhouse gas over 300 times more potent than carbon dioxide.
Dead zones
are hypoxic (low-oxygen) areas in the world's oceans and large lakes. caused by excessive nutrient pollution (usually nitrates and phosphates) from human activities, such as agriculture, sewage, and land runoff.
Cultural eutrophication: nitrates
are water soluble. can remain on fields and accumulate, leach into groundwater, end up in surface runoff, and/or volatize and enter the atmosphere where they contribute to acid precipitation. nitrate pollution is most damaging in wetlands where nitrogen is the limiting factor.
Formation of photochemical smog: 6 a.m. - 9 a.m.
as people drive to work, concentrations of nitrogen oxides and VOCs increase.
Formation of photochemical smog: 4 p.m. - sunset
as the sun goes down, the production of ozone is halted.
Formation of photochemical smog: 11 a.m. - 4 p.m.
as the sunlight becomes more intense, nitrogen dioxide is broken down and the concentration of ozone increases. NO2 + uv --> NO + O; O2 + O --> O3. nitrogen dioxide also reacts with water vapor to produce nitric acid and nitric oxide. Nitrogen dioxide can also react with VOCs released by vehicles, refineries, gas stations, and so on to produce toxic PANs (peroxacyl nitrates)
Formation of photochemical smog: 9 a.m. - 11 a.m.
as traffic begins to decrease, nitrogen oxides and VOCs begin to react, forming nitrogen dioxide
Sewage Treatment/Septic Systems: tertiary treatment
chemical treatment. a final stage to raise the effluent quality to the standard required before it is discharged to the receiving environment. specific steps may include sand filtration, lagooning, constructed wetlands, nutrient removal through biological or chemical precipitation, denitrification using bacteria, phosphorus removal using bacteria, and disinfection using UV light, chlorine, or ozone.
6 waterborne diseases
cholera, typhoid, shigella, polio, meningitis, and hepatitis. (usually come from sewage)
Acid deposition: affect on soil
contributes to the damage of many sensitive forest soils through nitrogen saturation and creating acidic conditions that are unhealthy for decomposers and mycorrhizal fungi. also leaches essential plant nutrients from the soil such as calcium, potassium, and magnesium. heavy metal ions that are contained within rock structures may be leached out of the rocks and into the soil structure.
The first set of pollutants recognized by the U.S. EPA as needing standards on a national level was
criteria air pollutants
Water pollution nonpoint sources
deliver pollutants indirectly through transport or environmental change. Ex.: when fertilizer from a farm field is carried into a stream by rain (run off). much more difficult to monitor and control than point sources. account for the majority of contaminants in streams and lakes.
The ultimate source of mercury to most aquatic ecosystems is
deposition from the atmosphere, primarily associated with rainfall.
primary pollutants
emitted directly into the air from natural sources such as volcanoes, mobile sources such as cars, or stationary sources such as industrial smokestacks.
Concentrations of VOCs may be 1,000 times higher _____ than ______.
indoors than outdoors
Two forms of smog
industrial smog and photochemical smog. industrial smog tends to be sulfur-based and is also called grey-air smog. Photochemical smog is catalyzed by UV radiation and tends to be nitrogen-based. photochemical smog is also called brown-air smog.
THE EPA's Acid Rain Program
is designed to achieve significant environmental and public health benefits through reductions in emissions of SO2 and NOx, the primary causes of acid rain. the program employs both traditional and innovative market-based approaches.
What secondary pollutant forms from SO2?
it combines with water vapor in the air to produce acid precipitation, which reduces the productivity of plants and causes breathing difficulties.
Water pollution: plastic: The Great Pacific Garbage Patch/Pacific Trash Vortex: As the plastic photodegrades into smaller and smaller pieces,
it remains as plastic polymers with some leaching toxic chemicals such as bisphenol A and PCBs, which then concentrate in the upper water column. As it disintegrates, the plastic becomes small enough to be ingested by aquatic organisms that reside near the ocean's surface.
Suspended Particulate Matter (PM10) results in
lung irritation and damage. many are known mutagens, teratogens, and carcinogens.
Ozone (O3)
major component of photochemical smog.
Algal boom definition
nitrates and phosphates are algal nutrients. increased concentrations of these nutrients increases the carrying capacity of lakes and streams. explosions in the amount of algae as a result of cultural eutrophication
Urban heat islands
occur in metropolitan areas that are significantly warmer than their surroundings. urban air can be 10F warmer than the surrounding area. One of the main reasons for higher-than-normal nighttime air temperatures in urban areas are buildings that reduce the radiation of urban heat to the night sky. thermal properties of surface materials like bricks, concrete, and asphalt store heat longer. the lack of vegetation and standing water in many urban areas also increases urban temps.
Temperature inversions
occur when air temperature increases with height above the ground, as opposed to the normal decrease in temperature with height. commonly occur at night when solar heating ceases and the surface cools, which then cools the atmosphere directly above the ground. a warm air mass then moving over a colder one keeps the cooler air mass trapped and their concentrations increasing. leads to pollution such as smog being trapped close to the ground, with possible adverse effects on human health (asthma, emphysema, and increases in lung cancer).
Water pollution point source
occurs when harmful substances are emitted directly into a body of water. Ex.: a pipe from an industrial facility discharging effluent directly into a river. point source pollution is usually monitored and regulated in developed countries.
Nonpoint source air pollution plus an example
occurs when the contaminant comes from a source that is not easily identifiable or from a number of sources spread over a large, widespread area. For example, people drive cars. When a car is running, the engine produces a variety of chemical products, including oxides of nitrogen (some of which are toxic) and molecules of unburned hydrocarbons from gasoline.
Point source air pollution plus an example
occurs when the contaminant comes from an obvious source. For example, a certain factory is producing chemicals. As part of the manufacturing process, certain poisonous chemicals and toxic gases result, such as benzene. The chemical company permits these toxins to be released from the stack at the factory without treating them. The untreated, toxic chemicals are released directly into the air.
5 types of solid waste
organic (veggies, flowers, leaves), radioactive (smoke detectors), recyclable (paper, glass, metals and some plastics), soiled (hospital wastes), toxic (paints, chemicals, pesticides)
Criteria air pollutants include (6)
ozone, particulate matter, carbon monoxide, sulfur dioxide, nitrogen oxides, and lead
The most common form of expressing air pollutants is
parts per million (PPM), where 1 ppm represents one particle of a pollutant for every 999,999 particles of air.
Most wastewater treatment facilities are not equipped to filter out
personal care products, household products, or pharmaceuticals. As a result, a large portion of these chemicals pass directly into local waterways.
Sulfur Dioxide (SO2) formation
produced by burning high-sulfur oil or coal, smelting of metals, and paper manufacturing.
Water pollution: thermal sources
produced by industry and power plants. heat reduces the ability of water to hold oxygen and causes death to organisms that cannot tolerate heat and/or low oxygen levels. global warming is also imparting additional heat to the oceans, rivers, and streams.
Formation of Industrial Smog: sulfuric acid
reacts with atmospheric ammonia to form brown, solid ammonium sulfate. H2SO4 + NH3 --> (NH4)2SO4
Formation of Industrial Smog: sulfur in oil and coal
reacts with oxygen gas to produce sulfur dioxide. S + O2 --> SO2
Formation of Industrial Smog: sulfur dioxide
reacts with oxygen gas to produce sulfur trioxide. SO2 + O2 --> SO3
Formation of Industrial Smog: sulfur trioxide
reacts with water vapor in the air to form sulfuric acid. SO3 + H2O --> H2SO4
Dry acid deposition
refers to acidic gases and particles. about half of the acidity in the atmosphere falls back to Earth through dry deposition. wind blows these acidic particles and gases. dry-deposited gases and particles may later be washed from trees and other surfaces by rainstorms --> the runoff water adds those acids to the acid rain, making the combination more acidic than the falling rain alone.
Wet acid deposition
refers to acidic rain, fog, and snow. as this acidic water flows over and through the ground, it affects a variety of plants and animals.
Secondary pollutants
result from the reaction of primary pollutants in the atmosphere to form a new pollutant.
The canyon effect
results from buildings reflecting and absorbing heat and blocking winds that reduce heat through convection.
What results from NO2?
results in lung irritation and damage, suppresses plant growth, and may be a carcinogen.
Peroxyacyl nitrates (PANs)
secondary air pollutants formed from the reaction of various hydrocarbons combining with oxygen and nitrogen dioxide and being catalyzed by UV radiation from the sun.