Download The Great Smog of 1952: Causes and Effects | PBHL 3100 and more Exams Community Health in PDF only on Docsity! The Great Smog of 1952 - London - Friday 5 to Tuesday, 9 December 1952 - Affected visibility significantly - Not thought of as major event - 4000 premature deaths and 100,000 sick - Later estimates: 10,000 premature deaths What caused it?? 1. Persistent thermal invasion (3-6 days)- cold, stagnant air trapped under a layer of warm air. 2. No wind movement/ stagnant wind 3. Enclosing topography 4. Pollution - Significant industrial pollution ie. Coal with high SO2 levels used in homes and industries - Local pollution (London) eg. Chimney smoke and diesel from cars, buses - High level buildup of toxins abt ground level Clean Air Act - These episodes provided the push for regulations to reduce emissions and air quality improvements - Clean Air Act of 1970 - NAAQs are regulated by EPA under this act - EPA’s Air Quality Index Criteria Air Pollutants - There are major outdoor air pollutants regulated by NAAQs (via EPA) 1. Particulate matter 2. Sulfur dioxide 3. Carbon monoxide 4. Nitrogen oxides 5. Ozone 6. Lead - Eastern States: high sulfate levels due to Power Plants - Western States: High NO and CO due to vehicle emissions - North West: high CO and NO due to wood burning - South West: high levels of windblown dust Health Effects - Increases hospital admissions and ER visits - Increased Resp. Symptoms - Declined pulmonary Function - Exacerbates chronic rresp. Disease and CVD - Lower overall mortality rates - Reduces visibility Particular matter - Products of combustion - First regulated total particulates - Six cities Study – death rates higher in most polluted cities - Smaller particles penetrate deeper into lungs - 1987 set standard for PM10 - 1997 set standards for PM2.5 - Lung cancer, other lung diseases, heart disease proportional to PM2.5 Sulfur Dioxide - Combustion of sulfur-containing fuels, especially coal - Irritates Nitrogen Oxides - Motor vehicles - Responsible for yellowish-brown smog - Irritates respiratory tract Ozone - Produced by sunlight acting on other air pollutants - Irritating to eyes and respiratory system - Increases mortality from cardiovascular and respiratory diseases Lead - Damages nervous system, liver and kidneys - Can be identified in blood - Pregnant women and children highly susceptible - Was used in leaded gasoline, banned in 1980s - Has decreased dramatically as an air pollutant - Major source is currently Metal Mining
