Chapter 10 - Air Quality

Define the following sources of air pollution and give examples: a. Stationary b. Mobile c. Natural d. Anthropogenic

a. A form of anthropogenic air pollution ; sources include electric generating plants, factories and manufacturing complexes, oil refineries, chemical plants, and incinerators. b. Another form of anthropogenic air pollution; sources include on-road vehicles, off-road vehicles, and non-road vehicles. c. There are several natural events that produce air pollutants, especially particulate matter. This includes wind storms, salt evaporation, and the production of materials that have a biological origin (mold spores, pollen, and organic materials from plants and animals). Forest fires can contribute as well. d. Human-made sources

Criteria air pollutants

A group of very common air pollutants regulated by the U.S. Environmental Protection Agency (EPA), including ozone, nitrogen dioxide, carbon monoxide, sulfur dioxide, particulate matter, and lead.

Smog

A mixture of pollutants, principally ground-level ozone, produced by chemical reactions in the air among certain chemicals (e.g., volatile organic chemicals).

How does air pollution impact the environment? In what ways can the pollutants NOx and SO2 damage structures and monuments over long periods of time?

Air pollution damages the environment and causes property damage. It reduces visibility in national parks such as the Grand Canyon in the U.S. and can even interfere with aviation. Environmental damage linked to air pollution includes harm to forests, lakes and other bodies of water, wildlife, and buildings. NOx and SO2 can damage structures over time as they fall through acid rain. They react with the water, oxygen, and other chemicals in rain water to form sulfuric and nitric acids. When acid rain falls, it creates high levels of acidity that can damage wildlife, the environment and human health. The effects of acid rain are especially noticeable when looking at old limestone statues, that are really susceptible to acid erosion.

Define what is meant by a temperature inversion. Explain how temperature inversions contribute to the creation of smog.

An atmospheric condition during which a warm layer of air stalls above a layer of cool air that is closer to the surface of the earth. It is the reverse of normal conditions, where the layer closer to the earth is warmer than the air in the upper atmosphere. The usual temperature gradient allows convection of warm air from the earth's surface into the upper atmosphere, thus removing pollutants from the breathing zones of people. During a temperature inversion, pollutants can build up when they are trapped close to the earth's surface.

Explain the adverse health effects attributed to carbon monoxide. Which population groups are likely to be most vulnerable to the effects of carbon monoxide exposure?

Carbon monoxide can be emitted from the combustion of fossil fuels by cars, trucks, and other vehicles. It can cause a reduction in the carrying capacity of the blood. This causes damage to the heart and lungs as they have to work harder to get the same amount of oxygen. Older adults with pre-existing conditions, such as chronic heart disease, anemia, or respiratory problems, are even more susceptible to the effects of this odorless, colorless gas.

Refer to the diagram that shows the anatomy of the human respiratory system (Figure 10.17, part A, p. 257). Which parts of the respiratory system are most likely to be affected by fine particulate matter?

Fine particulate matter primarily deposits in the respiratory bronchioles and alveoli. The smallest, end points of the lungs, the bronchioles and alveoli significantly increase the surface areas of the lungs but that also means it can be easy for particulate matter and other pollutants to get trapped deep in them. This can cause inflammation and irritation.

Define the term global warming and present arguments for and against the proposition that global warming has occurred during the past century. What environmental outcomes have been attributed to global warming?

Global warming is defined as an increase in the near-surface temperature of the earth, in part due to increased emissions of greenhouse gases and deforestation. Some argue that these changes in temperature and climate are a part of the earth's natural heating and cooling cycles. The earth has gone through periods of extreme weather, as we have evidence of ice ages and long periods of extreme heat. However, analyses of temperature changes over the past millennium have used data from tree rings and ice cores, and they indicate that the recent large temperature increases during the late 20th century are most likely due to anthropogenic activities that have increased greenhouse gases in the atmosphere. Just because it has happened naturally before doesn't mean it isn't being accelerated now by human activity (which it is).

Define what is meant by greenhouse gases and describe how they contribute to the greenhouse effect.

Greenhouse gases are gases that arise from natural sources and anthropogenic activities such as the burning of fossil fuels and that may accumulate in the atmosphere. They are referred to as greenhouse gases because in sufficient concentrations in the atmosphere, they may have the effect of trapping heat and causing the earth's temperature to rise.

Describe how ground-level ozone can be harmful to our health while ozone in the upper stratosphere plays an important role in protecting our health.

Ground-level ozone can cause respiratory difficulties such as reduced lung function, exacerbation of allergic respiratory disease, local irritation of the eyes and respiratory tract, and reduced ability to fight off colds and related infections. Environmental affects include reduced visibility, damage to forests and plants and oxidation effects that cause damage to certain kinds of fabric and rubber. In the upper stratosphere, ozone protects the earth from ultraviolet light.

Explain why environmental health experts are concerned about the possible adverse consequences of exposure to diesel exhaust. Describe one major adverse health effect that has been attributed to diesel exhaust. Name the risk groups that are most affected by exposure to diesel exhaust.

Health experts are concerned about exposure to diesel exhaust because there is potential elevated risk for lung cancer in those with high levels of exposure. Evidence suggests that workers directly exposed to diesel exhaust have lung cancer incidence rates that are 20% to 40% higher than non-exposed workers. The two groups of workers that are most at risk due to their exposure are truck drivers and railroad crews. Outside of adult workers, children are likely to be vulnerable to the effects of diesel exhaust because their defenses to ward off disease are not as well developed as those in adults.

Epidemiologic analyses have demonstrated a correlation between an increase in total daily mortality and an increase in air pollution. Give examples of historically significant fatal air pollution episodes that were characterized by extreme increases in air pollution and accompanying increases in mortality.

Meuse Valley, Belgium (resulting mortality rate: 10x more than normal) Donora, Pennsylvania (caused some form of illness in 14,000 residents; about 400 hospitalized; 20 deaths before the smog lifted) The Lethal London Fog of 1952 (resulted in 3,000 deaths above normal)

Air pollution

Refers to the presence, in various degrees, of substances not found in perfectly clean air.

Explain the difference between sick building syndrome and building-related illness. Describe the sources of indoor air pollution that can affect human health adversely.

Sick building syndrome (SBS) is a situation in which building occupants experience acute health and comfort effects that appear to be linked to time spent in a building, but no specific illness or cause can be identified. Building-related illness (BRI) is an identified diagnosable illness attributed directly to airborne building contaminants (such as asbestos or Legionnaires' disease). Indoor air pollution poses risks for respiratory illness of various types such as asthma. Sources include cockroaches, dampness, wall-to-wall carpeting, tobacco smoke, rodents, pets with fur, effluence from gas stove, construction materials with formaldehyde, dust mites, molds, bacteria, and fungi (p. e259).

Define the term Air Quality Index. How does the Air Quality Index aid in protecting the health of the population?

The Air Quality Index (AQI) is used to provide the public with an indication of air quality in a local area. It is a daily reporting of the air quality, telling the public how clean or polluted the air is that day. It aids in protecting the health of the population by focusing on the health effects you may experience within a few hours or days after breathing polluted air.

Normal ambient air

The air that we breathe.

Describe three methods for the control of greenhouse gases. Which method, if any, is likely to be most effective?

The following are the three methods of controlling greenhouse gases: • Planting of trees reduces the greenhouse gases in the atmosphere • Reduce, reuse, and recycle • Usage of energy efficient products None of these would be most effective because individual decisions about consumption and usage will not save the planet. The most effective method for controlling emissions would be to get a handle on the 117 people and companies that dump the most emissions on the planet.

Give examples of how air pollution endangers human health. Include in your discussion a review of the short-term and long-term health effects of air pollution.

The potentially damaging effects of air pollution are numerous. Long-term adverse human health effects associated with air pollution can include forms of cancer (lung, skin), and damage to vital tissues and organs (nervous system damage, impairment of lung and breathing function). Some short-term effects include respiratory symptoms (cough, sore throat, and difficulty breathing), and gastrointestinal symptoms (nausea and vomiting).