4- Environemental & Water Sanitation.pptx

Primary Health Care Lecture 4 Environmental Sanitation & Safe Water Supply Elements of PHC … Reminder 1. Health education. 2. Environmental sanitation & safe water supply. 3. Maternal & child health. 4. Immunization. 5. Proper nutrition. 6. Control of local endemic diseases. 7. Treatment of commo...

Primary Health Care Lecture 4 Environmental Sanitation & Safe Water Supply Elements of PHC … Reminder 1. Health education. 2. Environmental sanitation & safe water supply. 3. Maternal & child health. 4. Immunization. 5. Proper nutrition. 6. Control of local endemic diseases. 7. Treatment of common diseases & injuries. 8. Provision of essential drugs. Why We Need to Study the Environment? • We need to understand our interactions with the environment to creatively solve environmental problems. • We need to understand the rapidly changing global conditions to stop or modify the adverse changes. Definitions • Environment: all the living and non-living things around us: 1.Physical : water, soil, buildings, radiation etc. 2.Biologic: plants, animals, insects, bacteria, viruses. 3.Social: customs, cultures, habits, income, occupation, religion etc. • Environmental science is the study of: – How the natural world works. – How the environment affects humans Sanitation Sanitation is the hygienic means of preventing human contact from the hazards of wastes to promote health. Wastes that can cause health problems: • Human and animal: feces and solid wastes. • Domestic wastewater: sewage and sullage. • Industrial and agricultural wastes. • Appliances in disuse wastes like: cars, Special Names Garbage: Garbage is putrescible, animal and vegetable wastes resulting from the handling, storage, sale, preparation of food, cooking, and serving of food. Recyclable material: Recyclable material is solid waste that is processed and returned to the economic mainstream in the form of raw materials or products. Hazardous waste: Hazardous waste is a waste with properties that make it dangerous or potentially harmful to human health or the environment. Types of Sanitation  Basic sanitation • Refers to the management of human feces at the household level.  On-site sanitation • The collection and treatment of waste is done where it is deposited. Examples are the use of pit latrines, septic tanks.  Food sanitation • Refers to the hygienic measures for ensuring food safety. Types of Sanitation (Cont.)  Environmental sanitation The control of environmental factors that form links in disease transmission. Subsets of this category are: solid waste management, water and wastewater treatment, industrial waste treatment and noise and pollution control.  Ecological sanitation A concept and an approach of recycling to nature the nutrients from human and animal wastes. Ecological Sanitation Household & Industrial Waste • With changes in socio-economic conditions, there has been a trend toward increased household and industrial waste. • The situation is becoming difficult to cope with using the present incineration facilities and landfills. • For these reasons, a resource recovery and recycling policy is being promoted as an important measure. Environmental Health Administration The environmental health administration directs: • Environmental sanitation, • Food sanitation, • Milk & meat sanitation, • Water & waste disposal programs. So, it is deeply involved in the daily life of all citizens. Housing Environment • Housing and indoor environment have significant effects on physical, mental and social health and wellbeing. • Unsafe house can cause unintentional injuries like falls, drowning, poisoning, fires & choking. • Health threats can arise from indoor polluted air (e. g.; by use of solid fuels), noise, humidity and mold growth, temperature, presence of hazardous substances (e. g.; asbestos, lead and volatile organic compounds), bad hygiene and sanitation, and overcrowding. Substandard Housing Examples • • • • • • • • Inadequate sanitation. Lack of clean water. Lack of heating or cooling. Inappropriate ventilation. The presence of insects or vermin. Structural hazards. Faulty weather protection. Fire hazards. Water Sanitation • There can be no state of positive health and well being without safe water. • Water is not only a vital environmental factor to all forms of life but it has a great role to play in socio economic development of human population. • MDGs included safe water and sanitation in the attainable goals. • Water is integrated with other PHC components because it is an essential part of health education, food and nutrition and also MCH. How Water Affects Health? 1. Inadequate quantities of water affect the personal hygiene leading to health problems. 2. Consuming contaminated water may cause diarrhea, typhoid, viral hepatitis A, cholera, or dysentery (waterborne diseases). Safe Water This has been defined as water that is a. Free from pathogenic agents. b. Free from harmful chemical substances. c. Pleasant to taste i.e. free from color and odor. d. Usable for domestic purposes. Water Requirement A daily supply of 150 - 200 liters per capita is considered as an adequate supply to meet the needs for all urban domestic purpose. Sources of Water 1. Rain 2. Surface water e.g.; rivers. 3. Ground water e.g.; wills. Water Pollution Water contains impurities of two kinds: 1. Natural 2. Human made • Natural impurities are not essentially dangerous. They include dissolved gases (nitrogen, carbon dioxide, hydrogen sulphide) and dissolved minerals (salts of calcium, magnesium, sodium), suspended impurities like clay, slit sand and mud. • More serious aspect of water pollution is that caused by human activities urbanization and industrialization like: 1. Sewage. 2. Industrial waste. 3. Agricultural pollutants e.g.; pesticides. Biological & Chemical Harms of Water Biological Harms: 1.Those caused by the presence of an infective agents: a.Viruses : viral hepatitis A, hepatitis E, poliomyelitis, rotavirus. b.Bacteria: typhoid fever, bacillary dysentery, cholera c.Protozoa: Amebiasis, giardiasis d.Helminthes: roundworm, threadworm. 2. Those due to the presence of an aquatic host. e.Snail: schistosomiasis (Bilharziasis). f. Cyclopes: fish tape worm Chemical Harms: Detergents solvents, cyanides, heavy metals, minerals and organic acids, nitrogenous substances, bleaching agent, dyes. Purification of Water 1. Boiling: should be rolling boil for 10-20 minutes. 2. Storage. 3. Chemical disinfection: A. Chlorine (powder – solution – tablets). B. Iodine. C. Potassium permanganate. 3. Filtration. 4. Ozone gas. 5. Ultraviolet radiation. 6. Multi stage reverse osmosis purification of water. Disinfection Useful disinfectant in water supplies should: 1. Destroy pathogenic organisms present. 2. not leave products of reaction which makes water toxic or give color to water. 3. Have ready and dependable availability at reasonable cost permitting convenient safe and accurate application to water 4. Posses the property of leaving residual concentration to deal with small possible recontamination 5. be detected by practical rapid and simple analytical technique in the small concentration. Parameters in Drinking Water Physical Parameters Parameter Color Taste and odor Turbidity pH Limit < 15 TCU Should be acceptabl e < 1 NTU 6.5 - 8.5 Nephelometric Turbidity Un its (NTU) Total Dissolved Solids (TDS) Important Chemical Substances Constituents Barium Fluoride Lead Mercury Nitrate (as NO3) Nitrite (as NO2) Selenium Maximum limit (mg/liter) 0.7 1.5 0.01 0.006 50 3 0.04 Bacteriological Indictors • The primary bacterial indicator recommended for this purpose is the coliform group of organism as a whole. • Coliform organism include both fecal and non fecal organisms. • Typical example of fecal is E. coli and non fecal group is Klebsiella aerogens.