Environmental Health PDF

Environmental Health Asst. Prof. Dr. Basheer Al-Ali M.B.Ch.B ABHS/C.M Department of Family and Community Medicine College of Medicine/ Kerbala University  WHAT IS ENVIRONMENTAL HEALTH ? Environmental health is the field of science that studies how the enviro...

Environmental Health Asst. Prof. Dr. Basheer Al-Ali M.B.Ch.B ABHS/C.M Department of Family and Community Medicine College of Medicine/ Kerbala University  WHAT IS ENVIRONMENTAL HEALTH ? Environmental health is the field of science that studies how the environment influences human health and disease. Environmental health comprises those aspects of human health, including quality of life, that are determined by physical, biological, social, and psychological factors in the environment. It also refers to the theory and practice of assessing, correcting, controlling, and preventing those factors in the environment that can potentially affect adversely the health of present and future generations. Environmental hazards influence over 80% of the communicable and non-communicable diseases and injuries monitored by WHO. Overall, environmental hazards are responsible for about one-fourth of the total burden of disease worldwide. In developing countries, the burden of disease due to environmental hazards is heavily weighted towards communicable diseases. In developed countries, environmental hazards have a bigger impact on non-communicable diseases.  Environmental health hazards Industrial pollution Poor services of drinking water and sanitation Poor housing and town planning Lax control over eating establishments or food industry Poor quality roads Poor conditions in the workplace.  BASIC REQUIREMENTS FOR HEALTHY ENVIRONMENT Clean Air Safe and Sufficient Water Adequate and Safe Food Safe and Peaceful Settlements ‫مستوطنات سليمة‬ Stable Global Environment. AIR POLLUTION  Air pollution Is contamination of the indoor or outdoor environment by any chemical, physical or biological agent that modifies the natural characteristics of the atmosphere. It occurs when any harmful gases, dust, smoke enters into the atmosphere and makes it difficult for plants, animals and humans to survive as the air becomes dirty.  Air pollution is a major environmental risk to health. By reducing air pollution levels, countries can reduce the burden of disease from stroke, heart disease, lung cancer, and both chronic and acute respiratory diseases, including asthma. The lower the levels of air pollution, the better the cardiovascular and respiratory health of the population will be, both long- and short-term.  Atmospheric Composition Nitrogen 78.08% Oxygen 20.95% Argon 0.93% Carbon dioxide 0.04%  Types of Air Pollution Primary Air Pollutant Harmful substance that is emitted directly into the atmosphere (sulfur-dioxide emitted from factories) Secondary Air Pollutant Harmful substance formed in the atmosphere when a primary air pollutant reacts with substances normally found in the atmosphere or with other air pollutants (sulfuric acid). Air pollution may be DIVIDED into anthropogenic (man-made) & natural sources (e.g. dust storms & Volcanic action).  Factors contributes to Air Pollution A. Industrialization. B. Sharp increase in population size. C. Consumption of products. D. Urbanization. E. Mobility. F. Deforestation. ‫ازالة الغابات‬  Major Classes of Air Pollutants 1.) Carbon Monoxide 2.) Sulfur Dioxide 3.) Nitrogen Dioxide 4.) Particulate Matter 5.) Ground Level Ozone The other problems The greenhouse effect (Global warming) Thinning of upper ozone layer The greenhouse effect  The greenhouse effect is the process by which radiation from a planet's atmosphere warms the planet's surface to a temperature above what it would be without its atmosphere. A greenhouse gas (sometimes abbreviated GHG) is a gas in an atmosphere that absorbs and emits radiation within the thermal infrared range. This process is the fundamental cause of the greenhouse effect. The primary greenhouse gases in Earth's atmosphere are water vapor, carbon dioxide, methane, nitrous oxide, and ozone. water vapor 36–70% Carbon dioxide 9–26% Methane 4–9% Ozone 3–7%  Thinning of ozone layer Ozone Protects earth from UV radiation ozone molecules absorb UV light between 310 and 200 nm  Caused by human-produced bromine and chlorine containing chemicals Ex: CFCs The combination of loss of ozone shield & increase CO2 “from fuel consumption & destruction of rain forests” → ↑ CO2 → global warming or “Green house effect or phenomenon”. On average, a single chlorine atom is able to react with 100,000 ozone molecules before it is removed from the catalytic cycle. This fact plus the amount of chlorine released into the atmosphere yearly by chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) demonstrates how dangerous CFCs and HCFCs are to the environment  Effects of Ozone Depletion Higher levels of UV-radiation hitting the earth Eye cataracts Skin cancer Weakened immunity May disrupt ecosystems May damage crops and forests Water pollution Water is a basic human right & essential need. It has many uses including the irrigation of crops, the generation of electricity & for transport such as canals. In terms of protecting human health we are mostly concerned with the use of fresh water for domestic purposes. WHO currently estimates that over 1.1 billion people worldwide lack access to adequate supply of clean water. Uses of water in the domestic setting 1. Drinking. 2. Personal hygiene. 3. Cleaning e.g. cooking utensils. 4. Gardening e.g. garden vegetables.  QUANTITY Generally speaking a minimum of 20-40 liters per person per day is needed for drinking, personal hygiene & cleaning.  QUALITY The water should be free from chemical & biological contamination plus be acceptable in terms of color, taste & smell in accordance with the WHO Guidelines on the Quality of Drinking Water.  Water pollution is any contamination of water with chemicals or other foreign substances that are harmful to human, plant, or animal health. Water pollution occurs when a body of water is adversely affected due to the addition of large amounts of materials to the water. When it is unfit for its intended use, water is considered polluted. Worldwide, nearly 2 billion people drink contaminated water  The major sources of water pollution 1. Municipal, 2. Industrial, 3. Agricultural.  Sources of Pollution 1. Point (Direct) sources: e.g. effluent outfalls from factories, refineries, waste treatment plants etc… 2. Nonpoint (Indirect) sources: include contaminants that enter the water supply from soils/ atmosphere via rain water POLLUTANTS 1. fertilizers and pesticides 2. sewage and food processing waste 3. chemical contamination (e.g. from hazardous waste sites, industrial chemical wastes) 4. heavy metals ( e.g. lead, mercury) 5. organic material 6. petroleum 7. pathogens 8. suspended solids 9. radioactive substances THANK YOU