2Environmental Health
• Planet supplies us with: food, water, air, and everything that sustains our life.• Historically environmental health focused on
preventing infectious diseases spread by water, waste, food, rodents, and insects.• Expansion of the modern day definition.
• Encompassing all the interactions of humans with their environment and the health consequences of these interactions.
3Water Pollution
Causes:• Rapid growth of human population• Industrial outputs
Contaminants:• toxic chemicals• human and animal excrements • heavy metals • pesticides • silt • fertilizers
Sources of pollution:• Point sources• Non-point sources
4Groundwater
• Groundwater resources are valuable:– Purity– Dependability– Costs of Transportation– Treatment costs
• Groundwater pollution:– Waste storage, treatment or disposal facilities– Septic systems– Pipes, materials transport and transfer operation
5Water Contaminants
• 1. Biological• Bacteria : Typhoid fever, Cholera, Shigella (dysentery), Salmonella
and E. coli• Viruses: Hepatitis A, poliomyelitis and Rotavirus.
– Resistant to disinfection by chlorination• Protozoans: Giardia Lambia, Cryptosporidium, amoebic dysentery.
– Resistant to disinfection by chlorination
• 2. Chemical• Industrial solvents, pesticides• Lead• Nitrates
6Waste Disposal
•Humans generate large amounts of waste.• Sewage• Septic system• Heavy metal like lead, mercury etc• Polychlorinated biphenyls (PCBs)
• Solid waste• Garbage like newspapers, plastic bags
etc.• Sanitary landfill
7Why does sewage need to be treated?
• To improve the quality of wastewater so it can be discharged in waterways without seriously disrupting the aquatic environment or causing human health problems.
8Recreational Waters
In the year 2000, there were 1,266 beach closings, in Southern California, 92% due to elevated bacteria of undetermined causes. The remaining 8% was due to rain advisories and known sewage discharge.
9Global Air Pollution Issues
• Major causes:• Introduction of atmospheric pollutants in unusual
amounts• Changing the concentrations of natural atmospheric
components
• Significant impacts:1. Ozone depletion2. Global warming
10Air Pollution in Los Angeles
• We have some of the worst air in the nation, and the highest number of emergency visits caused by smog and air pollution
• Air pollution contributes to heart disease, lung disease, asthma and lung cancer
11Air Pollutants with Greatest Impact on Health
Outdoor• Ozone• Carbon monoxide• Airborne particles• Nitrogen oxides• Lead• Sulfur oxides• Diesel emissions
Indoor• Smoking• Mold• Dust mites• Radon gas
Solid Wastes
Classification• Municipal• Hazardous
Disposal methods• Unacceptable• Acceptable• Alternatives
13Factors That Contribute to Population Growth
• High fertility rates• Lack of family planning resources• Lower death rates• Population
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