ENVIRONMENTAL HEALTH

FUNDAMENTALS OF ENVIRONMENTAL HEALTH 1.The Environmental System Man-Environmental Relationship 2. Principles Of Environmental Control 3. Emerging Environmental Health Problem 4. Areas Of Environmental Health Concerns

DEFINITION OF TERMSEcology- The study of the relationship between organisms and their environment

Ecosystems - These are interdependent natural systems consisting of organisms and their environment. - All ecosystems consist of two components: Living or abiotic component Non-living or the non-abiotic component - Freshwater ecosystems - Marine water ecosystems

Environment- the sum total of an organisms external conditions and influences which affect its life and development.

Environmental health - the aspect of public health that is concerned with those forms of life, substances, forces and conditions in the surroundings of man that may exert and influence on mans health and development

Environmental Health Engineering- branch of engineering which is concerned with the protection of human populations from the effects of adverse environmental factors.

ENVIRONMENTAL HEALTH CONCERNS Access To Safe Water Supply Disposal Of Human Wastes Disposal Of Solid Wastes Disposal Of Hazardous And Toxic Wastes Air Pollution Use Of Persistent Chemicals Rapid Urbanization And Industrialization

Emerging Environmental Health Problems- lack of access to safe water supply- inadequate sanitary facilities- inadequate sanitary landfill- toxic and hazardous wastes- hospital waste- expired drugs- industrial slags- chemical waste- global warming- chemicals- rapid urbanization

NORMAL AIR IN THE TROPOSPHERE: 21% - OXYGEN 78% - NITROGEN

CO2 Cycle

Soil Functions Soil provides a platform for the activities of human society or land-based animals Soil provides the habitat for decomposer organisms which have essential role in the cycle of carbon and mineral nutrients Soil acts a purifying filter on water containing dissolved and colloidal constituents

water use in the Philippines

Water ResourcesMARINE WATER 7,098 islands 13,411 km. Coastline 1,123 M sq.km. of Sea Area 82% of provinces are in the coastline zone RIVERS 421 river systems 18 major river basins (drainage area is 1400 sq. km.) Cagayan River is the largest (area is 27280 sq km)

LAKES 72 natural lakes Laguna De Bay is the largest Lake Taal occupies a huge volcanic crater Lake Lanao is the largest in Mindanao

WETLANDS (swamps, mangroves) 100,000 hectares freshwater swamps Agusan Marsh Candaba Swamp

GROUNDWATER 14% of total water resource potential Estimated storage capacity is 1.22 million cu m 50% of the population use groundwater for drinking Extraction is regulated by NWRB

2,200 mm annual average rainfall11 Tropical cyclones average per year

Ecosystem Function Producers Consumers Herbivores Carnivores Omnivores Detritivores or Decomposers

LAND POLLUTIONIssues and Problems Mine Wastes And Tailing Disposal Siltation Of River Systems Heavy Metal Pollution Small Scale Mining

WATER POLLUTION Four of the major river systems in Metro Manila are biologically dead Out of the 421 rivers in the country 50 rivers were polluted and 16 were biologically dead Critical areas: Metro Manila, Southern Tagalog and Central Luzon Several beaches were polluted by organic wastes Laguna Lake depth reduced from 7 meters to 2.8 meters Nitrogen and phosphorus load increased by 10.8% to 24% Laguna Lake BOD levels: Suitable for fish production12 of the tributaries high levels Heavy metal contamination of inland waters in Mindanao and Luzon : industrial sources - Metro Manila, Central Luzon, Southern Tagalog, and Cebu mining sources - CAR and CARAGAPesticide pollution in rural areas is from agricultural runoff 58% of ground water sampled is contaminated with fecal coliform and needs treatment 31% of illnesses monitored for a five-year period were water-related diseases

Sources of Wastewater Domestic source Industrial source Storm water Agricultural runoff

WATER-RELATED DISEASES WATER BORNE WATER WASHED WATER BASED WATER INSECTRELATED

Economic Consequences

PRINCIPLES OF ENVIRONMENTAL CONTROL 1. ISOLATION separation by distance 2. SUBSTITUTION use of alternative materials, processes, and operations 3. SHIELDING use of barrier 4. PREVENTION Restriction of activities Immunization against diseases Use of prophylactic agents5. TREATMENT 5.1 Destruction applicable to biological hazards 5.2 Conversion of harmful substance to less harmful ones 5.3 Removal of harmful substances 5.4 Dispersion and dilution applicable to air and water pollutants

POTABLE and ADEQUATE WATER SUPPLY SOURCES: public water supply or individual supply source Water usage and classification Level of service QUALITY: - should meet requirements of PNSDW - Health aspects - regular sampling and test - Treatment methods QUANTITY: 90 liters per cap/day min

WATER SUPPLY SYSTEM Objectives of Water Supply System 1. To supply safe and wholesome water to consumers 2. To supply water in adequate quantity 3. To make water easily available to consumers so as to encourage personal and household cleanliness Wholesome water is one which is not polluted, free from toxic substances as well as excessive amounts of minerals and organic matters that may impair the quality of water. Potable water/Safe water is one that is suitable for domestic use and therefore safe to drink.

REQUIREMENTS OF PUBLIC WATER SUPPLY 1. Physically, chemically and bacteriologically safe. 2. Reasonably soft and neither scale forming nor corrosive. 3. Plentiful since shortage will force people to use doubtful sources. 4. Low in cost so that majority of the population can afford to be connected.

INSTITUTIONS INVOLVED IN WATER SUPPLYDENRPrincipal environment and water shed agency.

EMBEnforces water quality and effluent standards. Monitors quality of surface water.

DOHSets and monitors drinking water standards. Formulates and implements sanitation programs to address environmental and water related diseases.

LWUAPromotes and oversees the devt. of provincial waterworks and sewerage; acts as special lending institution for local water districts.

NWRBRegulate the use of water sources and does overall coordination of water resources management and development.

DOSTConducts research & devt. programs with DENR for prevention and abatement of water pollution.

MWSSResponsible for water systems in M.M. and its adjacent areas.

MWCIPrivate firm serving the waterworks and sewerage system of the eastern part of M.M.

MWSIPrivate firm serving the waterworks and sewerage system of the western part of M.M.

LLDARegulates and controls the pollution of the Laguna de Bay region, including the sewage works and industrial waste disposal systems.

LGUsShare responsibility in providing basic services, including enforcement of sanitation laws.

Water Supply and SanitationNational- 13,923,267Households with access to safe water supply 10,817,911 (78.3%) Households with sanitary toilet 9,649,470 (69.3%)

NCR-1,964,408Households with access to safe water supply 1,403,245 (71.4%) Households with sanitary toilet 1,320,502 (67.2%)

Region IV-2,161,159Households with access to safe water supply 1,635,664 (75.7)Households with sanitary toilet 1,534,696 (71.0)

WATER SOURCES1. Groundwater portion of the rainwater which has percolated into the earth to form underground deposits and called aquifer (water- bearing soil formations). Groundwater as a source of water supply can be extracted through the following: Groundwater Sources Shallow wells Natural spring Deep & artesian wells Horizontal galleries Infiltration galleries

a. Wells can be tapped by digging a hole or sinking pipes into the ground and installing water-drawing equipment. Wells are classified according to the following: - Deep Well are wells with depths greater than 20 meters constructed in areas characterized by aquifers located at a depth of more than 20 meters below ground surface. - Shallow Well are wells with depth of not more than 20 meters and are recommended for rural water supply development, particularly level I and II services. - Dug Well normally circular or rectangular in shape, with a diameter ranging from 1 to 1.5 meters.

b. Springs- spring water occurs when water in water-bearing stratum reaches the surface of the ground. Spring can be developed by enlarging the water outlet and constructing an intake structure for water catchment and storage.

DISADVANTAGE OF GROUND WATER SUPPLY- not available for large consumers - flow is uncertain - water is usually harder than surface water - pumping adds to the cost - rich in mineral content

2. Surface water is a mixture of surface run-off and groundwater. Surface sources include rivers, lakes, streams, ponds and impounding reservoirs. Usually more turbid Bacterial count is larger Water quality is variable Water temperature varies Warmer than wells during summer

DISADVANTAGE OF METEORIC WATER SOURCES varies from roof storage for individual home use larger prepared catchment areas for commercial use seasonal in occurrence water is corrosive rainwater is not sufficient to supply requirements

IMPROVED DRINKING WATER (WHO Definition) Improved drinking water sources are defined in terms of the types of technology and levels of services that are more likely to provide safe water than unimproved technologies. Improved water sources include household connections, public standpipes, boreholes, protected dug wells, protected springs, and rainwater collections.

Unimproved water sources are unprotected wells, unprotected springs, vendor-provided water, bottled water (unless water for other uses is available from an improved source) and tanker truck-provided water.

WATER USAGE AND CLASSIFICATIONClassificationBeneficial Use

Class AAPublic Water Supply Class I. Intended for waters having watersheds which are uninhabited and otherwise protected which require only approved disinfection in order to meet the PNSDW.

Class APublic Water Supply Class II. For sources of water supply that will require complete treatment (coagulation, sedimentation, filtration, disinfection) in order to meet the PNSDW.

Class BRecreational Water Class I. For primary contact recreation such as bathing, swimming, diving, etc. (particularly designed for tourism purposes).

Class C1) Fishery Water for propagation and growth of fish and other aquatic resources; 2) Recreational Water Class II (Boating ,etc.) 3) Industrial Water Supply Class I For manufacturing processes after treatment.

Class D1) For agriculture, irrigation, livestock watering, etc. 2) Industrial Water Supply Class II for cooling, etc. 3) Other inland waters

Uses of Water

Factors Affecting Per Capita Consumer1. Climate 2. Class Of Consumer 3. Quality Of Water 4. Industries And Commerce 5. Pressure In The Distribution System 6. Metering The System 7. Sewage Facilities 8. Number Of Inhabitants 9. Size Of Community 10. Cost

WATER-RELATED DISEASES1. Water- Borne Diseases- occur when the pathogen is in water which is drunk by a person which may then become infected - Methemoglobinemia, Cholera, Botulism, Typhoid, Hepatitis A, Dysentery, Cryptosporidiosis, Minamata Disease (mercury poisoning)

2. Water Washed- a disease whose transmission will be reduced following an increase in the volume of water used for hygienic purposes, irrespective of the quality of the water. - Trachoma, Cholera, Botulism, Typhoid, Hepatitis A, Dysentery, Enterobiasis, Ascariasis, Trichomoniasis, Trichuriasis, Pediculosis/Scabies

Three Main Types1. INFECTION OF THE INTESTINAL TRACT 2. INFECTION OF THE SKIN AND EYES 3. INFECTION CARRIED BY LICE

3.Water-Based- Disease due to infection by parasitic worms which depend on aquatic intermediate hosts to complete their cycle - Schistosomiasis, Chlonorchiasis, Fasciolopsiasis

4. Water Insect Related- Diseases transmitted by insects which either breed in water or bite near water - Malaria, Filariasis, Dengue

WATER SUPPLY SYSTEM1. SOURCES AND DISTRIBUTION 2. WATER QUALITY CHARACTERISTICS 3. QUALITY STANDARDS 4. HEALTH ASPECTS 5. WATER TREATMENT WATER SUPPLY- LEVEL OF SERVICE Level 1 (Point source) a protected well or a developed spring with an outlet but without a distribution system

Level 2 (Communal faucet system) a system composed of a source, a reservoir, a piped distribution network, and communal faucets.

Level 3 (Individual household connection) a system with a source, a reservoir, a piped distribution network and household taps.

LEVEL 1- POINT SOURCE a protected well or a developed spring with an outlet but without a distribution system Access to water supply facilities Farthest user not > 250 m. from the point source 1 Facility per 15 households Generally for rural areas where houses are scattered too thinly to justify a distribution system

LEVEL 2- COMMUNAL FAUCET SYSTEM a system composed of a source, a reservoir, a piped distribution network, and communal faucets. Access to water supply facilities Farthest house is not > 25 m. from communal faucet system 4 to 6 households per faucets Generally for rural areas where houses are clustered LEVEL 3- INDIVIDUAL HOUSEHOLD CONNECTION a system with a source, a reservoir, a piped distribution network and household taps. Access to water supply facilities The house has service connection from the system One or more faucets per household Generally for high-density built-up areas

The 2007 Philippine National Standards for Drinking WaterDOH ADMINISTRATIVE ORDER NO. 2007 0012

METHODS OF WATER TREATMENT 1. Removal of floating materials 2. Removal of suspended solids and color a. By sedimentation b. By coagulation c. By filtration 3. Removal of bacteria a. Same as in 2 b. Supplemented by disinfection 4. Removal or neutralization of taste, odor, minerals, and dissolved gases a. By aeration b. By treating the water with chemicals c. By means of special equipment or methods 5. Removal of hardness a. By membrane filtration b. By treating the water with chemicals

AerationAeration is the process by which gaseous phase, usually air, and water are brought into intimate contact with each other for the purpose of transferring volatile substances to or from the water. Volatile substances oxygen, carbon dioxide, nitrogen, hydrogen sulfide and methane.

CoagulationCoagulation is a process of combining small particles into larger aggregates.

FlocculationFlocculation is the physical process of producing contacts to form flocs.

SedimentationSedimentation is the process of solid-liquid separation using gravity settling to remove suspended solids. Type I settling out of discrete non- flocculent particles in dilute suspension. Type II settling out of flocculent particles in dilute suspension.

FiltrationFiltration processes are used primarily to remove suspended particulate material from water. Particulates removed may be those in the water source or those generated in treatment processes. Particulates clay, silt, microorganisms, colloidal and precipitates of iron and alum.

Disinfection of Water Supply- Disinfection is used to control the spread of communicable water borne diseases by killing pathogenic microorganisms found in drinking water. Chlorination is the most widely used disinfectant for water supplies

Effects required of a disinfecting agent in water supply: Bacterial effect the capacity to destroy pathogenic microorganisms in a given treatment process Residue or remnant effect the ability to disinfect water that is recontaminated in the distribution system due to seepage of pathogens into the pipes.

PrecipitationPrecipitation Method by Lime Soda Ash Process use of quick lime (calcium oxide), hydrated lime (calcium hydroxide) and soda ash (sodium carbonate). Ion-exchange Methods by Zeolite Softeners use of synthetic zeolite chemicals

Membrane Filtration ProcessesReverse Osmosis is a pressure driven process that retains all ions and passes water. Electrodialysis is a process in which ions are transferred through membranes from a less concentrated to a more concentrated solution as a result of the passage of direct current. Ultrafiltration is a pressure driven process for fractionating and concentrating solutions containing colloids and high-molecular weight materials.

WASTEWATERUSED WATER WASTE IN LIQUID FORM CONTAINING POLLUTANTS

composition of wastewater99.99% liquid0.01% solid

Preliminary Treatment

Tertiary TreatmentDissolved inorganic Reverse osmosis Distillation Oxidation of NH4+ to NO3- and denitrification of NO3- to N2, both by biological processes

Water Stabilization Pond

THE NEED FOR WASTEWATER TREATMENT protect receiving waters from faecal contamination protect receiving waters from oxygen depletion and ecological damage produce microbiologically safe eflluents for agricultural and aquacultural reuse

MOT of Excreta transmitted diseases

Category I non-latent, unable to multiply, low infective dose viruses, protozoa, enterobious, hymenolepistransmission foci: domestic, personal contamination control: improve domestic water supply, health education, improved housing

Category III latent, very persistent, no multiplication, no intermediate host geohelminths: ascaris, trichuris, hookworm, strongyloides transmission foci: yard, field and crop contamination control: treatment before land application, provision of toilets

Category IV latent, persistent, intermediate host(cow or pig) transmission foci: yard, field and fodder contamination control: provision of toilets, treatment before land application, thorough cooking, meat inspection

Category V latent, persistent, able to multiply, one or more intermediate aquatic hosts all water based helminths: schistosomiasis, clonorchiasis, fasciolopsiasis transmission foci: contaminated water control: provision of toilets, treatment before discharge, control of snails, cook fish and aquatic vegetation Category VI insect-related diseases diseases transmitted by mosquitoes which preferentially breed in polluted water

Complimentary InputsImprove water supplies (i, ii, iii & v) treatment to kill/remove Pathogens (ii, iii, iv & v) cooking of meat, fish & aquatic vegetables (iv & v) insect control (vi)health education (all categories)

GENERAL CONSIDERATIONS IN THE DISPOSAL OF EXCRETA 1. Wastes must not contaminate any drinking water supply. 2. They must not give rise to a public health hazard by being accessible to insects, rodents or other possible vectors which may come into contact with food or drinking water. 3. They must not give rise to public health hazard by being accessible to children. 4. They must not violate laws or regulations governing water pollution or sewage disposal. 5. They must not pollute or contaminate the waters of any bathing beach, shellfish- breeding ground, or stream used for public or domestic water-supply purposes, or for recreational purposes. 6. They must not give rise to a nuisance due to odor or unsightly appearance.

EXCRETA DISPOSAL

I. PIT LATRINEa. Conventional Pit LatrineCommon toilet facility in remote rural areas Consists of pit, squatting plate, foundation & structure Smells badly, breeding areas for insects Children may be afraid of falling into the pit b. Overhung Latrine c. Batch Compost Latrine d. Ventilated Improved Pit LatrineImportant Actions in the Pit Liquid portion of excreta seeps into the soil Solids are broken to simpler compounds by biological digestion Water is used only for hand washing or cleaning floor

2. POUR FLUSH TOILETAdvantages: Inexpensive Long-term solution Use low volume water Can be upgraded to connect to sewer Min. odor, insect and fly breeding In-house location

3. SEPTIC TANK

SEWERAGE AND SEWAGE DISPOSAL- Sewage disposal applies to the act of getting rid of sewage by any method. It may be done with or without previous treatment of the sewage.

Three Categories of Sewer Systems 1. Settled Sewer System2. Simplified Sewer System3. Conventional Sewer System

Settled Sewerage System Interceptor tank per house Regular emptying of vault Transport of liquid fraction of sewage Small-bore pipes: 3 to 4 Pipes laid in gardens or sidewalks Shallow excavation Simple inspection units Small decentralized tx stations

ADVANTAGES OF SMALL BORE PIPES 1. Being smaller in size, sewers will be economical 2. No risk of stream pollution 3. Quantity of sewage to be transported is small less cost.

Simplified Sewerage System Conveys black and gray water Small-bore pipes: 4 Self-cleansing flow Used in dense areas Pipes laid in gardens and sidewalks No deep excavation Small or no pumping stations Small decentralized tx plants

Conventional Sewerage System Transports gray and black water Pipes follow roads/streets Deep excavation Protection against heavy traffic Manholes give entrance to pipes Pumping stations Sewage treatment plants Disadvantage of Combined System Bigger sewers involve large excavation Dry weather flow being a small amount would result to silting up due to low velocity of flow Cost of pumping and treatment would increase due to large quantity of sewage Overflowing under worst condition may endanger public health