APES Unit 7

How does radon gas typically enter homes, and why is it dangerous?

Radon enters through cracks in foundations from soil containing uranium, and it is dangerous because it is a radioactive carcinogen linked to lung cancer.

How does temperature affect NOx formation during combustion?

NOx formation increases exponentially with flame temperature, especially above certain thresholds.

How does noise pollution affect aquatic animals like whales?

It causes stress, hearing loss, disrupted communication, and can interfere with migration and mating behaviors.

How do nitrogen oxides (NOx) form during combustion?

NOx forms when N2 combines with O2, especially during high-temperature combustion processes.

What health effect does carbon monoxide (CO) have on humans?

It binds to hemoglobin, reducing oxygen transport and causing suffocation in high concentrations.

What are natural sources of atmospheric CO2 and particulate matter?

Lightning, forest fires, volcanic eruptions, respiration, and decomposition.

What are the primary pollutants released from coal combustion?

CO, CO2, SO2, NOx, toxic metals (mercury, arsenic, lead), and particulate matter (PM).

What are examples of secondary air pollutants?

Tropospheric ozone (O3), sulfuric acid, sulfate, nitric acid, and nitrates.

What distinguishes PM10 from PM2.5?

PM10 particles are less than 10 micrometers in diameter, while PM2.5 particles are less than 2.5 micrometers, with PM2.5 capable of penetrating deeper into the lungs.

What distinguishes primary from secondary air pollutants?

Primary pollutants are emitted directly from sources, while secondary pollutants form in the atmosphere from primary pollutants through chemical reactions.

What is the primary effect of thermal inversion on air pollution levels?

Thermal inversion traps pollutants closer to the earth's surface, increasing pollution and respiratory health risks.

How does asbestos pose a health risk indoors?

Disturbed asbestos fibers can become airborne and cause lung diseases, including asbestosis and lung cancer.

How does thermal inversion affect air pollution levels?

It traps cold, polluted air near Earth's surface beneath a layer of warmer air, increasing pollution and health risks.

What are the effects of noise pollution on wildlife?

Disrupts animal communication, migration, and can cause physiological stress and hearing damage.

What natural process releases N2 in the atmosphere that can form NOx?

Lightning strikes convert N2 into NOx compounds.

Why are indoor air pollutants a concern in developing countries?

Because of indoor biomass burning with poor ventilation, leading to high concentrations of CO, PM, NOx, and VOCs, causing health issues.

What are the six criteria air pollutants identified by the Clean Air Act (1970)?

SO2, NOx, PM, CO, VOCs, and ground-level ozone.

How do temperature inversions occur?

They occur when a warm front moves over a cooler air mass or when hot urban surfaces cool overnight, trapping cold air near the surface.

How does aquatic noise pollution affect marine animals like whales?

It causes stress, disrupts communication and migration routes, and can lead to hearing loss.

What factors increase smog formation in urban areas?

Higher VOC emissions, increased vehicle traffic, more sunlight, warmer temperatures, and higher electricity demand.

What is the primary health effect of carbon monoxide (CO) exposure?

CO binds to hemoglobin, displacing oxygen and causing suffocation.

Why is CO2 not considered one of the six criteria air pollutants in the Clean Air Act?

Because CO2 does not directly lower air quality from a human health standpoint but is a greenhouse gas that contributes to global warming.

What is the difference between PM10 and PM2.5?

PM10 particles are less than 10 micrometers, while PM2.5 particles are less than 2.5 micrometers; the latter penetrate deeper into the lungs.

How does asbestos pose a health risk indoors?

Asbestos fibers can become airborne when disturbed, causing lung diseases such as asbestosis and mesothelioma.

What health effect does carbon monoxide (CO) have on humans?

CO binds to hemoglobin, displacing oxygen, and can cause suffocation and death in high concentrations.

What are the effects of noise pollution on wildlife?

Disrupts animal communication, migration, causes physiological stress, and can damage hearing.

How does radon enter homes and why is it a concern?

Radon diffuses from soil through cracks in foundations and is a radioactive carcinogen linked to lung cancer.

What was the impact of the EPA's phaseout of lead from gasoline starting in 1974?

It resulted in a 98% reduction in lead air concentrations in the US from 1980 to 2019.

What are the main precursors and conditions for photochemical smog formation?

NO2 broken down by sunlight into NO and O, VOCs reacting with NO, and sunlight driving O3 formation, especially in warm, sunny conditions.

What are common pollutants trapped during a thermal inversion?

Smog, particulate matter (PM), ozone, SO2, and NOx.

What is the effect of thermal inversion on air pollution?

It traps pollutants near the Earth's surface, leading to increased respiratory problems and environmental damage.

What are the environmental impacts of NOx emissions?

They cause respiratory irritation, lead to tropospheric ozone formation, and contribute to acid precipitation.

What are common sources of VOCs in indoor environments?

Adhesives, paints, cleaning products, plastics, and fabrics that release volatile organic compounds.

Why is indoor air pollution a major health concern in developing countries?

Because of the widespread use of biomass fuels like wood and manure for cooking indoors with poor ventilation, leading to high concentrations of pollutants.

Which natural sources release CO2 and PM into the atmosphere?

Forest fires, decomposition, volcanic activity, and respiration of living organisms.

What are common indoor sources of VOCs?

Household cleaners, adhesives, formaldehyde in particleboard, and emissions from plastics and fabrics.

How does flame temperature influence NOx formation?

Higher flame temperatures exponentially increase NOx formation, especially above certain thresholds.

What is the main cause of the trend in confirmed blood lead levels (BLLs) above 10 μg/dL from 1997 to 2015?

The reduction in leaded gasoline and lead-based paints due to environmental regulations has led to a significant decline in blood lead levels among children.

What pollutants are commonly trapped during a thermal inversion?

Smog, PM, ozone, SO2, and NOx are trapped, worsening air quality.

What health issues are associated with air pollutants during a thermal inversion?

Respiratory irritation, asthma flare-ups, worsened COPD, emphysema, and increased hospitalization.

How do temperature inversions occur?

Inversions occur when a cooler air mass is trapped beneath a warmer air layer, preventing vertical mixing.

What are examples of secondary air pollutants?

Ozone (O3), sulfuric acid, and nitric acid are secondary pollutants formed from primary emissions.

How does thermal inversion impact air pollution levels?

Thermal inversion traps pollutants near the Earth's surface, increasing pollution and associated health risks.

What are the effects of noise pollution on wildlife?

It disrupts communication, migration, and can cause physiological stress and hearing damage.

Why was lead phased out of gasoline starting in 1974?

Lead damages catalytic converters and is neurotoxic, so phasing it out reduced lead pollution and health risks.

How does acid rain affect soil and water pH levels?

Acid rain decreases soil and water pH, leading to soil acidification and water toxicity, which can harm plant and aquatic life.

How do environmental efforts since the Clean Air Act impact acid rain levels in the US?

They have significantly decreased acid deposition by reducing SO2 and NOx emissions from major sources like power plants and vehicles.

What is the difference between PM10 and PM2.5?

PM10 includes particles smaller than 10 micrometers, while PM2.5 includes finer particles smaller than 2.5 micrometers, with PM2.5 able to penetrate deeper into lungs.

How does radon gas typically enter homes, and why is it dangerous?

Radon seeps through cracks in foundations from underlying uranium-rich rocks, and its decay products can cause lung cancer.

What are the main natural sources of atmospheric CO2 and particulate matter?

Lightning, forest fires, respiration, decomposition, volcanoes, and sea spray are primary natural sources.

How do nitrogen oxides (NOx) form during combustion?

NOx form when nitrogen gas (N2) reacts with oxygen (O2) at high combustion temperatures.

What is the primary source of SO2 emissions, and what impacts does it have?

SO2 mainly comes from coal combustion, causing respiratory issues, visibility reduction, and acid precipitation.

What are the ecological effects of low pH levels on aquatic species?

Low pH levels cause mortality in sensitive insects, plants, fish, mollusks, and crustaceans, and can lead to harmful algal blooms.

What factors increase smog formation in urban areas?

Increased VOCs, vehicle traffic, sunlight, and temperature accelerate smog formation.

What are the effects of NOx emissions on the environment and human health?

NOx cause respiratory irritation, contribute to smog and acid rain, and facilitate ozone formation.

What are the main precursors of photochemical smog?

NO2, VOCs, sunlight, and warmth are key precursors that lead to ozone formation in smog.

What are common indoor sources of VOCs?

Adhesives, cleaning products, paints, plastics, and fabrics release VOCs into indoor air.

What are common indoor sources of VOCs?

Adhesives, paints, cleaning products, and certain plastics release VOCs that can irritate respiratory tissues.

How does asbestos pose a health risk indoors?

Disturbed asbestos releases fibers into the air, which can cause lung cancer and asbestosis.

How does aquatic noise pollution affect marine animals like whales?

It causes stress, hearing loss, disrupted communication, and can interfere with migration routes.

How does a catalytic converter reduce vehicle emissions?

It contains metals that catalyze reactions converting NOx, CO, and hydrocarbons into less harmful gases like N2, CO2, and H2O.

How does aquatic noise pollution affect marine animals like whales?

It causes stress, hearing loss, and disrupts navigation and communication, affecting migration and reproduction.

What is the primary purpose of pollution credits in air quality regulation?

They incentivize companies to reduce emissions by allowing them to sell excess reduction credits to others exceeding limits.

Why is indoor air pollution a major health concern in developing countries?

Due to reliance on biomass fuels like wood and charcoal for indoor cooking and heating, which release pollutants in poorly ventilated spaces.

How does asbestos pose a health risk indoors?

When disturbed, asbestos fibers become airborne and can cause lung diseases such as asbestosis and mesothelioma.

How does radon gas typically enter homes, and why is it dangerous?

Radon enters through foundation cracks and is dangerous because it is radioactive and increases lung cancer risk.

What is the difference between PM10 and PM2.5?

PM10 particles are less than 10 micrometers, while PM2.5 particles are less than 2.5 micrometers and penetrate deeper into lungs.

What distinguishes primary from secondary air pollutants?

Primary pollutants are emitted directly from sources; secondary pollutants form in the atmosphere through chemical reactions.