OUTDOOR AIR POLLUTION POLLUTANTS THAT AFFECT HEALTH

What is our air made of? Nitrogen 78% Oxygen 21% Water Vapor 0.01% at poles, 4% at tropics Argon less than 1% CO 2 0.038% Trace of particulates, CH 4 (methane), O 3 (ozone), and N 2 O (nitrous oxide)

Layers of the Atmosphere Troposphere Where the air we breath and our weather occurs Where most air pollution stays Location of greenhouse effect Has the most air pressure Stratosphere Location of the ozone layer Planes often fly in this layer Mesosphere Very thin air layer where meteor showers occur Thermosphere Where astronauts orbit within Thinnest layer of air molecules seen here

Discuss With A Partner For each pair, discuss which type of weather condition will reduce air pollution and which one will increase air pollution? For each choice, explain why! HOT vs COLD WET vs DRY WINDY vs STILL AIR

Place the terms into the correct category!! Things related to increasing pollutants to the air Things related to removing pollutants from the air Which column do these belong in? For each, write a sentence as to what this is and why it fits into its category. Catalytic Converter Electrostatic Precipitators Fluidized-bed Combustion Thermal Inversions Wet Scrubbers

Place the terms into the correct category!! Things related to adding pollutants to the air Things related to removing pollutants from the air Thermal Inversions Catalytic Converters Electrostatic Precipitators Fluidized-bed Combustion Wet Scrubbers

What term does this represent?

Common Primary Air Pollutants What is a Primary Pollutant? Any pollutant that comes from a direct source. The pollutant is not formed due to a chemical combination of other pollutants Common Outdoor Primary Pollutants CO NO x SO 2 Particulate Matter (PM) VOCs Lead

Common Secondary Air Pollutants What are Secondary Pollutants? Any pollutant that must be made when other pollutants chemically combine. Common Secondary Pollutants O 3 (Ground-level Ozone) Formed when VOCs and NO x molecules interact amongst sunlight Largest part of photochemical smog Photochemical Smog Hazy mix made up of mostly ozone along with other pollutants Industrial Smog Hazy mix made up of mostly from reactions between SO 2 and PM

Factors Increasing Outdoor Pollution Weather Factors Lack of wind High temperatures allow chemical reactions to occur Low precipitation and low humidity Urban buildings slow winds Mountains block wind movement

Factors Increasing Outdoor Pollution Thermal Inversion Normal weather patterns have air pollutants follow the warm air moving to cold air higher in the air In a thermal inversion, cold air settles at surface and is capped by a warm air mass Pollutants move up to the upper atmosphere. However, they hit the warm layer and stop moving The air pollutants stay near the city and reduce air quality

Factors Reducing Outdoor Pollution Weather Factors Windy climates move pollutants away Precipitation brings particles to the ground Cool, less sunny areas provide less opportunity for making secondary pollutants Time allows particulates to settle and for chemistry to change some chemicals Ocean spray brings particles to ground

Factors Reducing Outdoor Pollution Build tall smokestacks pollutants get placed high in the air for dispersal Use more fuel-efficient machines/ vehicles Use clean energies (solar, wind) versus fossil fuels (like coal, oil) Electrostatic Precipitators Particle-filled exhaust is fed through a negative charge plate to make particles negatively charged Exhaust then goes through a positively charged collection area Particles stick to collection area Exhaust comes out with less PM

Factors Reducing Outdoor Pollution Scrubbers The exhaust is fed through a scrubber It is sprayed with water and/or various chemicals Liquids grab and/or neutralize exhaust pollutants Waste materials collect at the bottom of the scrubber Can remove SO 2, PM, mercury

Factors Reducing Outdoor Pollution Fluidized-bed Combustion Fuel is burned in a hot bed of bubbling ash and sand. Hot air is blown through ash to make it act like a fluid. These conditions cause the fuel to burns at a lower temperature This results in lower emissions of air pollutants compared to regular combustion. Removes NO x, SO 2, PM

Factors Reducing Outdoor Pollution Catalytic Converters Used in vehicles Captures exhaust to change it to inert gases Changes: Hydrocarbons to water CO to CO 2 NO x to N 2. Problems: Can reduce fuel efficiency Need to be really hot to work can ignite Releases greenhouse gases

INDOOR AIR POLLUTION

Indoor Air Pollution In developed nations, indoor air pollution is usually a bigger health risk than outdoor air pollution Sick-building Syndrome (SBS) buildings in which people get sick in when they spend time in them (get better when not in them) 1 of 5 U.S. buildings are sick

Famous Indoor Air Pollutants Radon colorless, odorless, radioactive gas Sources: From natural decay of uranium in rocks and soil Usually enters home via cracks in basement or foundation Method to Reduce Exposure: Seal floors and walls of house Vent gas outside of house Health Problems: Radon is inert, but it decays into polonium. This causes lung cancer over repeated exposure

Asbestos Famous Indoor Air Pollutants Sources: Insulation used in older insulating materials since it retains heat well Method To Reduce Exposure: Removal of asbestos-containing materials (asbestos abatement) Cover & seal materials with asbestos Do not disturb materials with asbestos Health Problems: Sharp microscopic fibers cause lung damage when inhaled; Can ultimately lead to mesothelioma (a form of lung cancer) US has banned asbestos, but it is still used in many developing nations

Mold Famous Indoor Air Pollutants Sources: Water from leaks or flooding Poorly ventilated areas in damp environments Method To Reduce Exposure: Clean affected spots Pump water out of home Replace damaged surfaces Health Problems: Coughing and wheezing Throat irritation Possible skin irritation

Famous Indoor Air Pollutants Formaldehyde colorless gas Sources: Flooring Furniture Glues and resins Method To Reduce Exposure: Buy materials with low or no levels or formaldehyde Buy low to no-voc products Open windows and ventilate the house frequently Health Problems: Eye irritation Lung and breathing irritation

Indoor Air Pollution In developing nations, indoor cooking stoves cause the most exposure to indoor air pollution. Most stoves burn wood or biomass Leading pollutants are: Particulate matter (PM) linked to lung irritation, bronchitis, and lung cancer Carbon monoxide (CO) linked to CO poisoning Solution: Vent stoves out of house via chimney; Open windows; Cook outside

Air Pollution and Health According to WHO, 3 million people die early each year due to air pollution 73% of deaths related to indoor pollution In U.S., 150,000-300,000 people die a year due to air pollution. Most are related to inhalation of particulates from coal burning power plants 125,000 people in U.S. a year get cancer from breathing fumes from vehicles (especially diesel fumes)

Factors Increasing Outdoor Pollution Grasshopper Effect Pollutants from tropical areas are transported to polar areas due to wind/water currents This explains how pollution can get to areas without large populations (like the arctic/antarctic)