Lecture 4

Environmental Health

By Dr Fatima Alkhaledy
M.B.Ch.B;F.I.C.M.S/C.M.
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Environmental 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.

Water Pollution

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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

Groundwater

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

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Water 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

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Waste 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


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Waste Disposal
What You Can Do to Reduce Garbage
Products with least amount of packaging
Products made of recycled paper or recyclable products
Avoid using foam or paper cups
Store food in glass jars and reusable plastic containers
Recycle newspapers, glass, cans, paper, and any other recyclables
Do not throw electronic items
Start a compost pile
Stop junk mail

Why does sewage need to be treated?

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To improve the quality of wastewater so it can be discharged in waterways without seriously disrupting the aquatic environment or causing human health problems.




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Global Air Pollution Issues
Major causes:
Introduction of atmospheric pollutants in unusual amounts
Changing the concentrations of natural atmospheric components


Significant impacts:
Ozone depletion
Global warming

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Air 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

Air 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
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What You Can Do To Prevent Air Pollution
Cut back on driving
Keep your car tuned up
Buy energy-efficient appliances
Replace incandescent bulbs
Homes well insulated
Plant trees and shrubs
Proper disposal of ozone-depleting appliances
Keep house well ventilated
Don’t smoke
Clean and inspect chimneys, furnaces and other appliances

Solid Wastes

Classification
Municipal
Hazardous

Disposal methods

Unacceptable
Acceptable
Alternatives

FOOD SANITATION

According to Centers for Disease Control (CDC), the following factors contribute to mainly to foodborne illness:
63% Inadequate Cooling and Cold Holding Temperatures
29% Preparing Food Ahead of Planned Service
27% Inadequate Hot Holding Temperatures
26% Poor Personal Hygiene/Infected Persons
25% Inadequate Reheating

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Population Growth
World’s population currently estimated at 6.5 billion.
150 people every minute.
Increasing by 76 million per year
To exceed 9.1 billion by 2050
How Many People Can the World Hold?
Food
Available land and water
Energy
Minimum acceptable standard of living


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Factors That Contribute to Population Growth
High fertility rates
Lack of family planning resources
Lower death rates
Population

Thank You

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