Air Chapter 12

Section 1: What Causes Air Pollution?

Primary and Secondary Pollutants Air Pollution – Harmful substances built up in the air to an unhealthy level Pollutants can be from human activity – industry soot Pollutants can be natural – volcanic ash Primary Pollutant – put into air directly by human activity Soot from smoke and fires Primary and Secondary Pollutants

5 Types of Primary Pollutants and Their Sources Primary and Secondary Pollutants

Primary and Secondary Pollutants Secondary Pollutant – form when primary pollutants react with each other or natural substances Ground Level Ozone – is formed when car emissions (primary) interact with oxygen and UV rays (both natural) Primary and Secondary Pollutants

Is air pollution new? Clean Air Act 1970 – In 1273 King Edward I declared burning coal illegal “Be it known that whosoever shall be found burning coal shall suffer the loss of his head” Clean Air Act 1970 – Overseen by Environmental Protection Agency (EPA) Regulates the emissions (what comes out the tailpipe) of automobiles The EPA required the gradual elimination of lead in gasoline. To date lead pollution has been reduced by more than 90 % in US. California – Zero Emission Law – Is that possible? Battery operated vehicles are the only “true” ZEVs (zero emission vehicles)

Industrial Air Pollution Industrial plants burn fossil fuels Burning releases – Sulfur Dioxide and Nitrous Oxide Power Plants emit 2/3 of ALL SO2 and 1/3 of ALL NO VOCs (Volatile Organic Compounds) - chemical compounds that form toxic fumes Given off by – Oil refineries, Dry Cleaners, Chemical plants Clean Air Act Requires Industries to use: Scrubber: cleans emissions of plants by washing it and filtering it Electrostatic Precipitator: uses static charges to get particulates to clump together and collect, clean gas continues on. (used in cement factories/coal burning plants) Industrial Air Pollution

Smog: Air pollution that hangs over urban areas and reduces visibility

Temperature Inversion: Air circulation usually stops pollution from accumulating to dangerous levels. Inversions trap pollution near the Earth’s Surface Temperature usually decreases with altitude But a warm layer above a cold layer will trap pollution (Hot air rises, right? Hot smoke rises, but if atmosphere is just as warm, the smoke stays put)

That’s all for 12.1 Time for a reading quiz

Section 2: Air, Noise, and Light Pollution

Effects of Air Pollution on Health Many air pollution effects are short term Can be reversed when exposure is decreased Short term effects: Nausea Headaches Eye Irritations Coughing Upper respiratory infections (bronchitis, pneumonia) Will make asthma worse

Effects of Air Pollution on Health Many air pollution effects are long term Cannot be reversed when exposure is decreased Long term effects: Emphysema Lung Cancer Heart Disease May damage lungs of young children

Air inside a building is sometimes WORSE than air outside Chemicals used in making carpets, furniture, paints can pollute indoor air Sick Building Syndrome – buildings with very poor air quality Found in hot climates where buildings are sealed to keep out heat. Fungi can grow and there is no release of the toxic chemicals released from carpet, paint etc. All builds up to drastically reduce indoor air quality Indoor Air Pollution

Indoor Air Pollution Preventing bad indoor air pollution Radon Gas Remove the source of the pollution Remove carpet, new paint Good ventilation to mix the indoor air with outdoor air Decreases the amount of pollution per unit of air Radon Gas Colorless, odorless gas – 2nd leading cause of lung cancer Occurs after uranium decays, found naturally in the earth, can seep into houses. Have a radon detector in the house Indoor Air Pollution

Indoor Air Pollution Asbestos A fire resistant substance used in building materials before the 1970s. When inhaled the fibers can cut and scar the lungs leading to breathing difficulties and heart failure. Billions of dollars have been spent in asbestos removal Indoor Air Pollution

Noise Pollution Defined as unwanted sound Noise kills nerve cells in the ear 12% of teens have permanent hearing loss Intensity of sound is measured in decibels 120 dB is at the threshold of pain. Noise levels greater than this can cause permanent damage. Protection from noise pollution: Mufflers on autos and yard equipment MP3 players in Europe can only go up to 100 dB Ear protection

Light Pollution Not a direct hazard to human health Does impact environment and enjoyment of night sky. Bigger threat is wasted energy Upward directed light is wasted, only goes to space

That’s all for 12.2 Time for a reading quiz

Section 3: Acid Precipitation

What Causes Acid Precipitation? Acid precipitation is rain with a high concentration of acids pH measures acid concentration Low numbers are more acidic. Below 7 is acidic. The closer to zero – the more acidic. Each change in pH (1 to 2) indicates a ten times difference in acidity Normal rain has a pH of 5.6, acid precipitation starts at 5.0 What Causes Acid Precipitation?

What Causes Acid Precipitation

How Does Acid Precipitation Affect Soils and Plants Acidification – Increase of acid in soils or lakes Acid chemically reacts with soil minerals Some nutrients are dissolved and washed away from where plants can use them Metals like aluminum are released into the soil and possibly absorbed High enough levels of these metals can be toxic How Does Acid Precipitation Affect Soils and Plants

Acid Precipitation and Aquatic Ecosystems Aquatic animals live within a very narrow pH range Acid rain changes pH level of lake and kills fish Acid precipitation leaches metals like aluminum from soil near lake/river Metals accumulate in fish bodies until reach toxic levels Acid Shock In the spring when acid snow melt and flows into rivers and lakes the sharp change in pH kills massive amounts of aquatic creatures

Acid Precipitation and Humans Humans depend on plants, animals, and seafood items for food If plants, animals, fish die off we lose food sources. Toxic metals taken in by plants, animals, fish also accumulate in us and can reach toxic levels Aesthetics – Statues and buildings are deteriorating due to acid rain

Controlling Acid Rain Acid rain is hard to regulate because the pollution that causes it blows with the wind. One country’s pollution could float into another country causing acid rain there. Countries are signing Air Quality agreements with each other to help reduce polluting emissions

That’s all for 12.3 Time for a reading quiz