Human Impact on the Atmosphere Human Impact on the Atmosphere Chapters 18 and 19 Living in the Environment, 11 th Edition, Miller Advanced Placement Environmental Science La Canada High School Dr. E

Clean Air Act Originally signed 1963 – States controlled standards 1970 – Uniform Standards by Federal Govt. – Criteria Pollutants Primary – Human health risk Secondary – Protect materials, crops, climate, visibility, personal comfort

Criteria Air Pollutants EPA uses six "criteria pollutants" as indicators of air quality 1. Nitrogen Dioxide: NO 2 2. Ozone: ground level O 3 3. Carbon monoxide: CO 4. Lead: Pb 5. Particulate Matter: PM 10 (PM 2.5) 6. Sulfur Dioxide: SO 2 Volatile Organic Compounds: (VOCs) EPA established for each concentrations above which adverse effects on health may occur

Other Air Pollutants Carbon dioxide Carbon dioxide ChloroFluoroCarbons ChloroFluoroCarbons Formaldehyde Formaldehyde Benzene Benzene Asbestos Asbestos Manganese Manganese Dioxins Dioxins Cadmium Cadmium

...when polluted air is stagnant (weather conditions, geographic location) Los Angeles, CA Smog Forms

Photochemical Smog Primary Pollutants NO 2 + Hydrocarbons Auto Emissions UV radiation H 2 O + O 2 Secondary Pollutants HNO 3 O 3 nitric acidozone Photochemical Smog

Indoor Air Pollution

Why is indoor air quality important? 70 to 90% of time spent indoors, mostly at home Many significant pollution sources in the home (e.g. gas cookers, paints and glues) Personal exposure to many common pollutants is driven by indoor exposure Especially important for susceptible groups – e.g. the sick, old and very young – Allergies, asthma

Sources of Indoor Air Pollutants Building materials Furniture Furnishings and fabrics Glues Cleaning products Other consumer products Combustion appliances (cookers and heaters) Open fires Tobacco smoking Cooking House dust mites, bacteria and molds Outdoor air

Important Indoor Air pollutants Nitrogen dioxide Carbon monoxide Formaldehyde Volatile Organic Compounds (VOCs) House dust mites (and other allergens, e.g. from pets) Environmental tobacco smoke Fine particles Chlorinated organic compounds (e.g. pesticides) Asbestos and man-made mineral fibres Radon

Radon 55% of our exposure to radiation comes from radon colorless, tasteless, odorless gas formed from the decay of uranium found in nearly all soils levels vary

Radon: How it Enters Buildings Cracks in solid floors Construction joints Cracks in walls Gaps in suspended floors Gaps around service pipes Cavities inside walls The water supply

Radon: Reducing the Risks Sealing cracks in floors and walls Simple systems using pipes and fans

Clinically Recognized Building-Related Diseases –Pontiac Fever – Legionella spp. –Legionnaire's Disease –Hypersensitivity Pneumonitis –Humidifier Fever –Asthma –Allergy –Respiratory Disease Chronic Obstructive Pulmonary Disease