Air and Water Pollution: Causes, Effects, and Solutions

What is smog?

A mixture of several pollutants that collects in the troposphere, primarily caused by air pollution from transportation.

What are pollutants?

Chemicals that have negative health and environmental effects, produced by natural events or anthropogenic activities.

What are primary pollutants?

Pollutants that have a direct impact on the environment.

What are volatile organic compounds (VOCs)?

A group of primary pollutants including hydrocarbons like methane, propane, and octane, which can cause health issues and contribute to smog.

What are chlorofluorocarbons (CFCs)?

Primary pollutants previously used in aerosols and refrigerants, known for depleting the ozone layer.

What health effects are associated with VOCs?

Irritation of the respiratory tract, headaches, nausea, organ damage, nervous system damage, and some are suspected or known carcinogens.

What are carbon oxides?

Primary pollutants including carbon monoxide (CO) and carbon dioxide (CO2), with various health and environmental effects.

What are the health effects of carbon monoxide (CO)?

It can be poisonous, causing nausea and drowsiness by preventing oxygen delivery to cells.

How can carbon monoxide emissions be reduced?

By using catalytic converters in automobiles.

What is carbon dioxide (CO2) and its environmental impact?

A greenhouse gas produced from the complete combustion of fossil fuels, decomposition, and cellular respiration.

What are nitrogen oxides (NOx)?

Primary pollutants including nitric oxide (NO), which can lead to respiratory damage and contribute to smog.

How is nitric oxide produced?

During the combustion of fossil fuels.

What are the health effects of nitrogen oxides (NOx)?

Can cause lung damage, aggravate asthma, and increase susceptibility to respiratory infections.

What is sulfur dioxide (SO2)?

A primary pollutant produced by the combustion of coal and oil, which can be reduced using scrubbers.

What are particulate matter (PM)?

Tiny particles of dust, soot, and liquids that can cause respiratory issues and other health problems.

What are the health effects of lead (Pb)?

Extremely toxic to nerve cells.

What is mercury (Hg) and its impact?

A toxic element produced by coal combustion that can bioaccumulate and harm nerve cells.

What are secondary pollutants?

Pollutants that are formed when primary pollutants combine with other atmospheric components.

What is nitric acid (HNO3) and how is it formed?

A secondary pollutant produced when NOx reacts with atmospheric water, leading to acid rain.

What is sulfuric acid (H2SO4) and its formation?

A secondary pollutant produced when SOx reacts with atmospheric water.

What is ozone in the context of air pollution?

A secondary pollutant formed when NOx, CO, and VOCs react in sunlight, harmful to plants and animal respiratory systems.

What are the effects of ozone in the troposphere?

It can damage plant structures, animal respiratory systems, and contribute to temperature inversions.

What is the role of sunlight in the formation of ozone?

Sunlight facilitates the reaction of NOx, CO, and VOCs to produce ozone.

What causes photochemical smog?

Photochemical smog is produced when nitrogen oxides (NOx) react with VOCs in the presence of light.

What are the main components produced by photochemical smog?

Airborne particles and ground-level ozone.

How does increased light affect ozone production?

More light, such as during the summer, leads to more ozone production.

What is the relationship between altitude and temperature in the troposphere?

Temperature usually decreases with increasing altitude in the troposphere.

How can photochemical smog affect air circulation?

Smog can cause a temperature inversion, preventing the circulation of air.

What are urban heat islands and what causes them?

Urban heat islands are areas that are 3-5°C warmer due to heat-trapping materials, less plant life, and automobile use.

What is sick building syndrome?

Sick building syndrome is a phenomenon where occupants of energy-efficient buildings experience allergies, headaches, fatigue, and respiratory problems due to trapped toxic pollutants.

What is the Clean Air Act and when was it passed?

The Clean Air Act was passed in 1970 and authorizes the EPA to establish air quality standards and regulate hazardous pollutants.

What significant amendment was made to the Clean Air Act in 1990?

The amendment required the phase-out of ozone-depleting CFCs and encouraged market-based principles to reduce emissions.

How does emission trading work under the Clean Air Act?

Companies can buy SO2 allowances from each other to stay within legal emission limits, allowing for economic gains.

What is the function of catalytic converters?

Catalytic converters convert toxic gases and pollutants in exhaust gas into less toxic pollutants through a chemical reaction.

What is a scrubber and its purpose?

A scrubber is an air pollution control device used to remove particulate matter and gases from industrial exhaust systems.

What environmental disaster occurred in the Cuyahoga River in 1969?

The Cuyahoga River spontaneously burst into flame due to severe pollution, primarily from oil.

What legislation was passed in response to the Cuyahoga River fire?

The Clean Water Act was passed in 1972, partially in response to the environmental disaster.

What was the condition of the Cuyahoga River after the fire?

The river became a 'dead river' with no oxygen, making it impossible for plant or animal life to survive.

What is the current status of the Cuyahoga River?

The river has made a remarkable recovery and is now capable of supporting aquatic life.

What is dissolved oxygen and why is it important?

Dissolved oxygen is a substance in water required for living organisms to survive.

What is the chemical composition of water?

Water is made of two hydrogen atoms and one oxygen atom that unevenly share their electrons.

What role do VOCs play in air pollution?

VOCs (volatile organic compounds) react with nitrogen oxides to contribute to the formation of photochemical smog.

What is a temperature inversion?

A temperature inversion occurs when warmer air traps cooler air at the surface, preventing air circulation.

How do urban heat islands affect local climates?

Urban heat islands can raise local temperatures, impacting weather patterns and energy consumption.

What are some health effects associated with sick building syndrome?

Health effects include allergies, headaches, fatigue, and respiratory problems.

What is the significance of the Clean Water Act?

The Clean Water Act established regulations to protect water quality and prevent pollution in U.S. waters.

What is the result of disproportionate sharing in water molecules?

It leads to partial charges on the water molecule and the attraction of one water molecule to another, known as hydrogen bonding.

What role does dissolved oxygen (DO) play in aquatic environments?

Dissolved oxygen is necessary for aquatic animal life.

How is dissolved oxygen concentration measured?

It is measured in parts per million (ppm).

What is the threshold of dissolved oxygen (DO) ppm that can support fish populations?

A DO ppm below 3.0 is too low to support fish populations.

What does pH measure in a solution?

pH measures the hydrogen ion concentration of a solution.

What is the pH range for solutions?

The pH scale ranges from 0 to 14.

What does a pH less than 7 indicate?

It indicates high concentrations of hydrogen ions.

What does a pH greater than 7 indicate?

It indicates high concentrations of hydroxide (OH-) ions.

What is the pH of a neutral solution?

A neutral solution has a pH of 7.

What is the significance of the logarithmic nature of the pH scale?

One step on the pH scale represents a tenfold change in hydrogen ion concentration.

How can changes in pH affect aquatic life?

Subtle changes in pH can severely damage aquatic life.

What is turbidity a measure of?

Turbidity measures how clear the water is.

How is turbidity expressed?

It is expressed as the amount of light scattered by the water, measured in nephelometric turbidity units (NTUs).

What can cause increased turbidity in water?

Higher levels of clay, silt, organic matter, algae, or other microscopic organisms.

What are the effects of excessive turbidity on aquatic ecosystems?

It can limit light for aquatic plants, lower net primary productivity, and indicate the presence of metals and bacteria.

What are some harmful bacteria indicators of water quality?

Fecal coliform, E. coli, and enterococci species.

What are common sources of harmful bacteria in water?

Poorly-treated sewage, livestock waste, and inefficient septic systems.

What primarily causes poor water quality conditions like low pH or dissolved oxygen?

The presence of water pollutants.

What is the relationship between turbidity and sedimentation?

Excessive turbidity can cause increased sedimentation and siltation, harming aquatic life.

What biological processes can water pH affect?

Water transport in fish gills and amphibian skin, as well as the solubility of hazardous metals.

What happens to turbidity levels after a rainstorm?

Turbidity levels typically increase as substances are washed into streams and rivers.

What are infectious agents or pathogens in water pollution?

Fecal coliform, E. coli, viruses, and parasitic worms that originate from human and animal waste, causing diseases like typhoid fever and cholera.

What are the sources and impacts of oxygen-depleting wastes?

Sources include farm runoff, sewage, and industrial discharge. They cause eutrophication and hypoxia.

What are inorganic chemical pollutants and their effects?

Includes mineral acids, toxic metals like lead and mercury, and mineral salts. They can render water undrinkable, cause cancer and birth defects, and kill aquatic life.

What types of organic chemical pollutants are there?

Includes oil, gasoline, and pesticides from industrial discharge and runoff, causing cancer, birth defects, and nervous system damage.

What are plant nutrient pollutants and their consequences?

Sources include urban sewage and agricultural runoff. They lead to eutrophication, algal blooms, and hypoxia.

What is the impact of sediments in water pollution?

Erosion of soil increases turbidity, reducing sunlight availability and can cause cancer.

What sources contribute to radioactive materials in water?

Fallout from nuclear testing and waste from nuclear power plants, including iodine-131 and strontium-90.

What is thermal pollution and its effects?

Heat generated and discharged by power plants warms water, depleting oxygen levels.

How can water pollutants be classified?

As point sources (e.g., wastewater discharge) or nonpoint sources (e.g., runoff).

What are the eight classes of water pollutants?

They include infectious agents, oxygen-depleting wastes, inorganic chemicals, organic chemicals, plant nutrients, sediments, radioactive materials, and thermal pollution.

What environmental disaster led to the classification of the Cuyahoga River as a 'dead zone'?

Increased nitrogen and phosphorus levels from agricultural runoff caused hypoxia.

What is a 'dead zone' in aquatic environments?

A region of hypoxia characterized by reduced oxygen levels, often caused by nutrient overloads.

How does agricultural runoff contribute to algal blooms?

Nutrients from fertilizers promote phytoplankton and algae growth, leading to blooms that deplete oxygen when decomposed.

What is the significance of the Mississippi River in relation to water pollutants?

It contributes large amounts of oxygen-depleting wastes and plant nutrient pollutants to the Gulf of Mexico, creating one of the largest dead zones.

What health risks are associated with arsenic in drinking water?

Long-term exposure to low concentrations can cause cancer and damage the central nervous system, respiratory system, and organs.

How does arsenic enter the water supply?

From weathering of arsenic-rich minerals and human activities like coal burning and smelting.

What was the impact of shallow water wells in Bangladesh?

They reduced pathogenic diseases like cholera but many produced water rich in arsenic, leading to health issues.

What are the effects of thermal pollution on aquatic life?

It warms water, which can deplete oxygen levels, harming fish and other aquatic organisms.

What are the common sources of plant nutrient pollutants?

Urban sewage, runoff from farms and gardens, and household wastewater.

What are the consequences of sediment pollution in water bodies?

Increased turbidity reduces sunlight availability, affecting aquatic ecosystems.

What types of diseases can be caused by infectious agents in water?

Diseases such as typhoid fever and cholera.

What are the main pollutants that can cause cancer in water?

Inorganic chemicals, organic chemicals, and sediments.

What role do fertilizers play in water pollution?

They contribute to nutrient pollution, leading to algal blooms and hypoxia.

What is the estimated number of people exposed to toxic levels of arsenic in Bangladesh?

Approximately 77 million people.

What has the WHO called the situation of arsenic exposure in Bangladesh?

The largest mass poisoning of a population in history.

What is a primary objective of government agencies regarding water quality?

To maintain water quality.

How is surface water from rivers treated for drinking?

It is usually chlorinated to kill bacteria and other microbes.

What happens to water after it has been used for drinking and domestic purposes?

It is collected and treated at a wastewater treatment plant before re-entering the environment.

What is one major source of water pollution mentioned in the notes?

Runoff.

How does land development affect water runoff?

Runoff increases as land is developed and water-absorbing land is covered with concrete.

What significant environmental law was passed by Congress in 1972?

The Federal Water Pollution Control Act, commonly known as the Clean Water Act.

What is the main purpose of the Clean Water Act?

To maintain and restore water quality, making it swimmable and fishable.

What did the Clean Water Act make illegal?

It became illegal to dump pollution into surface water without formal permission.