POTABLE and ADEQUATE WATER SUPPLY• SOURCES: public water supply orindividual supply source• QUALITY:• should meet requirements of PNSDW• regular sampling and test• health aspects• treatment methods• QUANTITY: 90 liters per cap/day min
AREAS OF ENVIRONMENTALHEALTH CONCERNS1. WATER SUPPLY 6. VECTOR CONTROL2. SANITATION 7. AIR RESOURCEMANAGEMENT3. WASTEMANAGEMENT8. OCCUPATIONALHEALTH4. SOIL POLLUTION 9. URBANIZATION5. FOOD SANITATION
WATER SUPPLY SYSTEM1. SOURCES ANDDISTRIBUTION2. WATER QUALITYCHARACTERISTICS3. QUALITYSTANDARDS4. HEALTH ASPECTS5. WATER TREATMENT10<<<NEXT>>>
14Water Supply SystemsWATER SOURCES1. Groundwater – portion of the rainwaterwhich has percolated into the earth to formunderground deposits and called aquifer(water-bearing soil formations).Groundwater as a source of water supplycan be extracted through wells and springs.
SURFACE WATER SOURCES2. Surface Water – is a mixture ofsurface run-off and groundwater.Surface sources include rivers, lakes,streams, ponds and impoundingreservoirs.15
163. METEORIC WATER SOURCES• VARIES FROM ROOF STORAGE FOR INDIVIDUALHOME USE• LARGER PREPARED CATCHMENT AREAS FORCOMMERCIAL USE• SEASONAL IN OCCURRENCE• WATER IS CORROSIVE• RAINWATER IS NOT SUFFICIENT TO SUPPLYREQUIREMENTS
17Water Supply SystemsWater Usage and ClassificationFresh Surface Waters (rivers, lakes, reservoirs,etc.)Classification Beneficial UseClass AA Public Water Supply Class I.Intended for waters havingwatersheds which are uninhabitedand otherwise protected whichrequire only approved disinfectionin order to meet the PNSDW.
18Classification Beneficial UseClass A Public Water Supply Class II.For sources of water supply that willrequire complete treatment(coagulation, sedimentation, filtration,disinfection) in order to meet thePNSDW.Class B Recreational Water Class I.For primary contact recreation such asbathing, swimming, diving, etc.(particularly designed for tourismpurposes).Water Usage and Classification
19Water Usage and ClassificationClassification Beneficial UseClass C 1) Fishery Water for propagation andgrowth of fish and other aquaticresources;2) Recreational Water Class II(Boating ,etc.)3) Industrial Water Supply Class IFor manufacturing processes aftertreatment.Class D 1) For agriculture, irrigation, livestockwatering, etc.2) Industrial Water Supply Class II forcooling, etc.3) Other inland waters
21Water Supply SystemsWATER SUPPLY-LEVEL OF SERVICELevel 1 (Point source) – a protected well or a developedspring with an outlet but without a distribution systemLevel 2 (Communal faucet system) – a system composedof a source, a reservoir, a piped distribution network, andcommunal faucets.Level 3 (Individual household connection) – a systemwith a source, a reservoir, a piped distribution networkand household taps.<<<NEXT>>>
22Classification of Water Supply Facilities• Level 1 (Point source) – a protected well or a developed spring withan 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 justifya distribution systemWATER SUPPLY-LEVEL OF SERVICE<<<BACK>>>
23Classification of Water Supply Facilities• Level 2 (Communal faucet system) – a system composed of asource, a reservoir, a piped distribution network, and communalfaucets.• 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 clusteredWATER SUPPLY-LEVEL OF SERVICE<<<BACK>>>
24Classification of Water Supply Facilities• Level 3 (Individual household connection) –a system with a source, a reservoir, a pipeddistribution network and household taps.• Access to water supply facilities• The house has service connection from thesystem• One or more faucets per household• Generally for high-density built-up areasWATER SUPPLY-LEVEL OF SERVICE
25Institutions Involved in WaterSupplyDENR Principal environment and watershed agency.EMB Enforces water quality andeffluent standards. Monitorsquality of surface water.DOH Sets and monitors drinking waterstandards. Formulates andimplements sanitation programsto address environmental andwater related diseases.
26Institutions Involved in WaterSupplyLWUA Promotes and oversees the dev’t.of provincial waterworks andsewerage; acts as special lendinginstitution for local waterdistricts.NWRB Regulate the use of watersources and does overallcoordination of water resourcesmanagement and development.
27Institutions Involved in WaterSupplyDOST Conducts research & dev’t.programs with DENR forprevention and abatement ofwater pollution.MWSS Responsible for water systems inM.M. and its adjacent areas.
28Institutions Involved in WaterSupplyMWCI Private firm serving thewaterworks and seweragesystem of the eastern part ofM.M.MWSI Private firm serving thewaterworks and seweragesystem of the western part ofM.M.
29Institutions Involved in WaterSupplyLLDA Regulates and controls thepollution of the Laguna de Bayregion, including the sewageworks and industrial wastedisposal systems.LGUs Share responsibility in providingbasic services, includingenforcement of sanitation laws.<<<NEXT>>>
30COMMON WATER QUALITYPROBLEMS IN WATER SUPPLYA. PhysicalCharacteristics Source/Cause ProblemTurbidity SuspendedparticlesCloudy waterColor Substances insolutionColored waterOdor Dissolved saltsand gasesDisagreeableodorTaste DissolvedsubstancesUnpleasant taste
31COMMON WATER QUALITYPROBLEMS IN WATER SUPPLYB. ChemicalCharacteristics Source/Cause ProblemHardness Dissolvedminerals of Ca &MgIncreased soapconsumption,formation ofscalesChloride Dissolved salts insewageSalty taste ofwaterIron Dissolved iron Staining offixtures, metallictaste
32COMMON WATER QUALITYPROBLEMS IN WATER SUPPLYC. BiologicalCharacteristics Source/Cause ProblemBacteriaVirusesparasitesSewage Water – RelatedDiseasesMicroscopicPlantsNutrients(N,P,K)Color, odor,taste<<<BACK>>>
33The 2007 Philippine NationalStandards for DrinkingWaterDOH ADMINISTRATIVE ORDER NO. 2007 – 0012
34Water Quality Issues• New information on many chemicals•Evolving agricultural, industrial, domesticpractices• Proliferation of water-refilling stationsas alternative (or main) sources ofdrinking water•Distinct standards for “processed” water<<<NEXT>>>
Type of Chemicals UseNumber of Tons Used peryear in the CountryPesticide AgriculturalPublic HealthConsumer UseNo available data3.04(a)No available dataFertilizers 1,353,224.38(b)Petroleum Products 2008: 101,200(c)*2009: 107,299(d)*Industrial ChemicalsA. PCL Manufacturing/processing594,904.51(e)B. ODS (transitional) 4,510,704.10 kg +29,034.00 kegs(f)Consumer Chemicals No available data*in thousand barrelsChemical Use by Categories
Chemical Waste GenerationType of Chemical WasteGeneration (tons/year)2008 2009Cyanide with Waste 5,551,042 81,517.10Acid Wastes 19,666,025 5,654.91Alkali Wastes 1,966,258 198,926.36Wastes with inorganic chemicals 532,251 45,818.05Reactive Chemical Wastes 1,406,982 7,547.36Inks/ Dyes/ Pigments/ Paint/ Latex/Adhesives/ Organic Sludge520,517 14,678.21Waste organic solvent 78,369,374 3,525.04Putrescible/Organic wastes 29,490 912,373.58Oil 3,743,566 295,907.10Containers 33,196,202 129,170.90Immobilized wastes 397,469 5,290.40Organic chemicals 2,154,458 210.29Miscellaneous waste (pathogenic orinfectious wastes, friable asbestoswastes, pharmaceuticals and drugs,pesticides, persistent organicpollutants)17,390,465 10,575.26TOTAL 164,924,099 1,711,194.55
37Water Quality Issues• Detection of naturally occurringhazardous substances in water sources•E.g. arsenic, fluoride• Inadequate monitoring capability•Inability of regulatory units to monitor allparameters• Need for new approaches in safemanagement of water supply
38STANDARD PARAMETERS AND VALUESFOR DRINKING WATER QUALITYI. Standard Values for Bacteriological QualitySource and Mode of Supply Bacteria Standard Value(No/100 ml)All drinking water supplies underall circumstancesE. Coli orthermotolerantfecal bacteria0Treated water entering thedistribution systemE. Coli orthermotolerantfecal bacteria0Treated water in the distributionsystemE. Coli orthermotolerantfecal bacteria0
39II. Standard Value for Biological OrganismsConstituent Permissible ValueTotal Count/ ml 10
40III. Standard Values for Physical andChemical Quantity: Health SignificanceA. Inorganic ConstituentsConstituent Maximum Level (mg/l)Antimony 0.005Arsenic 0.01Barium 0.3Boron 0.7Cadmium 0.003Chromium 0.05Cyanide 0.07Fluoride 1.0Lead 0.01Mercury (total) 0.001Nitrate 50.0Nitrite 3.0Selenium 0.01
42IV. Standard Values for Physical and ChemicalQuality: Aesthetic QualityConstituents Maximum Level (mg/l)Taste UnobjectionableOdor UnobjectionableColor 5 TCUTurbidity 5 NTUAluminum 0.2Chloride 250.0Copper 1.0Hardness 300 as CaCO3Hydrogen Sulfide 0.05Iron 1.0Manganese 0.5pH 6.5 - 8.5Sodium 200.0Sulfate 250.0Total Dissolved Solids 500.0Zinc 5
43V. Standard Values for Disinfectants andDisinfectant By-ProductsConstituent Maximum Level (mg/l)a. DisinfectantChlorine Residual 0.2 - 0.5b. Disinfectant by-productsBromate 0.025Chlorite 0.22,4,6 trichlorophenol 0.2Formaldehyde 0.9Phenolic substances 0.001Bromoform 0.1Dibromochloromethane 0.1Bromodichloromethane 0.06Chloroform 0.2
44VI. Chemicals of No Health Significanceat Concentrations Normally Found inDrinking WaterConstituent NoteAsbestos In accordance with thefindings of WHO, the DOHdoes not prescribe anystandard values for thesecompounds since they arenot hazardous to humanhealth at concentrationsfound in drinking water.SilverTin
45VII. Standard Values for RadiologicalConstituentsConstituent Maximum Level (mg/l)Gross alpha activity 0.1Gross beta activity 1.0<<<BACK>>>
46MINIMUM FREQUENCY OF SAMPLING FORDRINKING WATER SUPPLY SYSTEMSSource andmode of supplyPopulation served Minimum frequency ofsamplinga. Level I 90 – 150 Once in every 3 monthsb. Level II 600 Once in every 2 monthsc. Level III Less than 50005000 – 100000More than 1000001 sample monthly1 sample per 5000 popmonthly20 samples plus one sampleper 10000 pop monthlyd. Bottled Water Once every 2 monthse. Water refilling stations Once a monthf. Emergency supplies of drinking water Before delivery to users<<<BACK>>>
WATER-RELATED DISEASES WATER BORNE WATER WASHED WATER BASED WATER INSECTRELATEDMethemoglobinemiaCholeraBotulismTyphoidHepatitis ADysenteryCryptosporidiosisMinamata DiseaseTrachomaEnterobiasisAscariasisTrichomoniasisTrichuriasisPediculosis/ScabiesSchistosomiasisChlonorchiasisFasciolopsiasisMalariaFilariasis<<<BACK>>>
48WATER-BORNE DISEASESoccur when thepathogen is inwater which isdrunk by a personwhich may thenbecome infected,e.g. cholera andtyphoid.
49WATER-WASHED DISEASES• A DISEASE WHOSETRANSMISSION WILLBE REDUCEDFOLLOWING ANINCREASE IN THEVOLUME OF WATERUSED FOR HYGIENICPURPOSES,IRRESPECTIVE OFTHE QUALITY OF THEWATER.
50THREE MAIN TYPES OF WWD1. INFECTION OF THE INTESTINALTRACT2. INFECTION OF THE SKIN ANDEYES3. INFECTION CARRIED BY LICE
51WATER-BASED DISEASES• Disease due toinfection by parasiticworms whichdepend on aquaticintermediate hoststo complete theircycle, e.g.schistosomiasis,fasciolopsiasis.
52WATER-RELATED INSECTDISEASES• Diseasestransmitted byinsects which eitherbreed in water orbite near water,malaria, dengue andyellow fever.<<<BACK>>>
53METHODS OF WATERTREATMENT1. Removal of floating materials2. Removal of suspended solids andcolora. By sedimentationb. By coagulationc. By filtration3. Removal of bacteriaa. Same as in 2b. Supplemented by disinfection
54METHODS OF WATERTREATMENT4. Removal or neutralization of taste,odor, minerals, and dissolved gasesa. By aerationb. By treating the water with chemicalsc. By means of special equipment ormethods5. Removal of hardnessa. By membrane filtrationb. By treating the water with chemicals
55TYPES OF PRETREATMENTPROCESSES• Screening – remove and screen large objects• Bar screens• Wire mesh screens• Presedimentation – remove silts, sands andgrits• Microstraining – remove nuisance particles• Chemical pretreatment – controls the growthof algae• Use of copper sulfate
59COAGULATION/FLOCCULATION• Coagulation is a process of combiningsmall particles into larger aggregates.• Flocculation is the physical process ofproducing contacts to form flocs.
62SEDIMENTATION• Sedimentation is the process of solid-liquid separation using gravity settling toremove suspended solids.• Type I – settling out of discrete non-flocculent particles in dilute suspension.• Type II – settling out of flocculent particlesin dilute suspension.
63FILTRATION• Filtration processes are used primarilyto remove suspended particulatematerial from water. Particulatesremoved may be those in the watersource or those generated in treatmentprocesses.• Particulates – clay, silt, microorganisms,colloidal and precipitates of iron andalum.
65• Precipitation Method by Lime –Soda Ash Process – use of quicklime (calcium oxide), hydratedlime (calcium hydroxide) andsoda ash (sodium carbonate).• Ion-exchange Methods by ZeoliteSofteners – use of syntheticzeolite chemicals
66• Membrane Filtration Processes• Reverse Osmosis – is a pressure drivenprocess that retains all ions and passes water.• Electrodialysis – is a process in which ions aretransferred through membranes from a lessconcentrated to a more concentrated solutionas a result of the passage of direct current.• Ultrafiltration – is a pressure driven process forfractionating and concentrating solutionscontaining colloids and high-molecular weightmaterials.<<<BACK>>>
68ObjectivesAt the end of the session, theparticipants should be able to: discuss the various health effectscaused by these substances inwater describe the different physicaland chemical properties of water
69H A Z A R D SEXPOSUREPATHWAYDOSE-RESPONSEH EALTHEFFECTSWater QualityIngestion,Skin ContactAge, Sex,Nutritional Status,Genetics, etc.Various Infectionsand Poisoning(Physical, Chemicaland Biological)
70TurbidityColorOdorPhysical Characteristicsof water
71Turbidity• Caused by a wide variety of suspendedmaterials--colloidal to coarse dispersion• Common in surface waters• Sources: runoff from rain andflood (clay and silt),Streetwashings, Industrial wastes
72Environmentalsignificance of turbidity Filterability - more difficult andcostly Disinfection - interferes witheffectiveness ofdisinfection Aesthetics - undesirableappearance
73ColorApparent color: caused bysuspended matterTrue Color: caused by dissolvedvegetable or organicextracts
74 Imparts aesthetic problems toacceptability of waterPublic Health Significance ofColorInterferes with chlorination process byreacting with chlorine to form chloroformand other trihalomethanes(THM), orchlorinated organics. These may posecertain health risks to consumers
75Chemical Properties ofWater pH, acidity and alkalinity Water hardness Iron and Manganese Chloride Fluoride Sulfate
77pH, Acidity andAlkalinitypH - expresses the intensity of the acidand alkaline condition of waterpH ------------------ 7 ----------------- 14Acidic AlkalinepH - expresses the hydrogen ion conc.H2O ---------- H+ + OH-
78Forms of acidity in water : Carbon dioxide Mineral acidity (Nitric, sulfuric, phosphoricacids, etc) Carbon dioxide imparts pleasant taste Mineral acidity makes water unpalatablethat deters consumption Increases corrosivity of water andpotential for leaching heavy metalsEnvironmental significanceof acidity:
79Alkalinity - measure of thecapacity of water to neutralizeacids bicarbonates, carbonates andhydroxides borates, silicates and phosphatesAlkalinity imparts acrid (mapakla)taste to water
80Water HardnessHardness is caused by multivalentmetallic cations : CalciumMagnesiumStrontiumIronManganese
81Sources of HardnessContact of water with soil and rockformations Under low pH due to presence ofcarbon dioxide, water can dissolvebasic materials, i.e. limestoneformations Common in groundwater
82Classification of wateraccording to degree ofhardnessmg/L Degree of Hardness0 – 75 Soft75 – 150 Moderately hard150 – 300 Hard300 up Very hard
83Significance of Hardness Increases soap consumption toproduce foam or lather Produces scale in hot water pipes,boilers, and heaters Epidemiological studies indicatedinverse relationship betweenhardness of drinking water andcardiovascular diseases
84Iron (Fe) and Manganese(Mn) Present in soil in insoluble form Under certain acidic conditions, Fe andMn become soluble When exposed to air, these areconverted to insoluble form Imparts yellow stain color and rustytaste (Fe) and black stain (Mn)
85Chloride naturally occurring spray from ocean is carried inlandas droplets saltwater (sea) intrusion intoground water Irrigation water Human excreta Industrial wastessources:
86Significance of Chloride Imparts salty taste at concentrationsbeyond 250 mg/L No known adverse health effects topeople who consume more than2000 mg/L
87FluorideAt high concentrations promotedisfigurement of teeth in humans“mottled enamel” or dentalfluorosisAt low levels (less than 1.0mg/L),dental caries become prevalentSignificance:
88Sulfate At concentrations above 250 mg/L,impart cathartic (purgative)effect Promotes formation of scales inboilers and heatersSignificance in drinking water
89NitrogenInterferes with the water disinfectionprocess Nitrates at levels above 50 mg/L,may cause infantile hemoglobinemiaor “blue babies”Sources: naturally-occurring, organicwastes
90Phosphorus and Phosphates Together with nitrogen, phosphorusserve as nutrients for planktonscausing “algal blooms” Polyphosphates are used in publicwater supplies for controllingcorrosionSignificance
92ArsenicSources: dissolution of minerals and ores, geothermal springs Industrial effluents (powergeneration from coal-firedfurnaces, metal smelters) atmospheric deposition
93Health Effects of Arsenic Hyperkeratosis, blackfoot diseasemycardial schemia,liver dysfunction Inorganic arsenic is a documentedhuman carcinogen
94CadmiumSources: wastewater pollutionAir pollution depositionImpurities in galvanized pipes,solders and metal fittings
95Health Effects of Cadmium Main routes of exposure are inhalationand ingestion Kidney is the main target organ ofcadmium (Itai-itai disease) Cardiovascular diseases accompaniedby hypertension
97CyanideHealth effects:thyroid and nervous systemdysfunctionSource: industrial contaminationof drinking water sources
98LeadSources:• dissolution of lead in minerals and soil• Household plumbing fixtures, fittings,solder and pipes
99Lead At high concentrations, hematological,renal and neurological impairments,reproductive effects including impairedfertility and fetal wastage At lower levels include impaired growth ofchildren, and increases blood pressureHealth effects
100MercurySources:• inorganic and organic mercury arenaturally occurring in surface andgroundwater• Mining wastes where mercury is used forore processing• Industrial processing wastes- electricalapparatus, paper
101Mercury Teratogenic effects of organomercurialshave been documented Congenital fetal “Minamata disease”(neurological defects) Cerebral palsy, impaired learning andbehavioral disabilityHealth Effects
102Aldrin LindaneDieldrin MethoxychlorChlordane ToxyphaneEndrin 2,4-DHeptachlor 2,4,5- TOrganic constituents withhealth significanceWide range of health effects: carcinogen,teratogen, mutagen
103Chloroform* Phenolic substancesFormaldehyde BromoformBromate dibromochloromethane*Bromodichloromethane*By-products of waterdisinfection*THM- trihalomethane
104 carcinogenic effects effects on reproduction anddevelopment toxic effects on the liver and kidneyHealth effects of disinfectionby-products
107Common Treatment Processes Dissolved Impurities Dissolved inorganic• Oxidation-filtration for Fe and Mn salts• Hot or cold lime softening or other precipitation processesfor heavy metals• Chlorination for cyanides• Ion-exchange softening and dealkalization dionization• Reverse osmosis• Electrodialysis• Distillation• Oxidation of NH4+ to NO3- and denitrification of NO3- to N2,both by biological processes
108Common Treatment Processes Dissolved organic• Flocculation followed by Sedimentation,Filtration, ultrafiltration, activated carbon• Biological treatment• Chemical destruction by e.g. chlorination,ozonation, potassium permanganate• Ion Exchange scavenging
109Common Treatment Processes Suspended Impurities Colloids: organic and inorganic• Flocculation processes• Biological treatment for BOD reduction• Ultrafiltration Suspended inorganic• Sedimentation / screening inorganic Suspended organic• Sedimentation / screening• Filtration• Biological treatment for BOD
110Common Treatment Processes Living Matter Microorganisms – reduced by biological treatment• Microfiltration• Disinfection by chlorine, ozone or biocides• Ultraviolet or radioactive sterilization Gases• Thermal and/or mechanical degassing for removal of O2and CO2• Chemical scavenging (e.g. O2 removal by sulfite orhydrazine)• Dechlorination with activated carbon• Ion exchange
111General Methods ofWater Treatment Removal of floating materials, which is generallyaccomplished by screens Removal of suspended solids and color which may beaccomplished: By sedimentation – or permitting water to remain quiescent inlarge settling basin so that the suspended solids may settle tothe bottom. By coagulation - or applying to the water certain chemicalscalled coagulants that produce an insoluble gelatinous andflocculent precipitate which absorbs and entraps thesuspended solids in the water and thus hastens theirsedimentation By filtration – or passing the water through a layer of sand orother material that retains the suspended solids.
112General Methods ofWater Treatment Removal of bacteria which is accomplished by generally by the process mentioned for the removal ofsuspended solids supplemented by final disinfection with chlorine or otheracceptable physical or chemical agents to ensure thedestruction of bacteria that may cause disease Removal or neutralization of tastes, odors,objectionable minerals and dissolved gases which isaccomplished : By aeration, or exposing the water in thin films or droplets tothe oxygen of the atmosphere By treating the water with certain chemicals By means of special equipment or methods
Sanitation Code of the Philippines(PD 856) Requirements in the Operation of IndustrialEstablishments (RULE V) Section E: Disposal of Industrial Wastes• All toxic and hazardous wastes including nuclearwastes incident to the operation of the industrialplant shall be collected, stored or disposed of in amanner that will prevent health hazards, nuisanceand pollution in accordance with the guidelines setby DENR (RA 6969).• All industrial establishments discharging toxicwastes shall submit a copy of the method oftreatment approved and certified by the EMB-DENR .
Philippine Clean Water Act(RA 9275) Ch. 2 Art 1 Sec 8 – Domestic SewageCollection, Treatment and Disposal That all establishments including industrialcomplex and similar establishments must beconnected to a sewerage system. Sec. 12 – Categories of Industry Sector The Department shall revise and publish a listof categories of industry sector for whicheffluent standards will be provided for eachsignificant wastewater parameter.123
Philippine Clean Water Act(RA 9275) SEC. 14. Discharge Permits. The Department shallrequire owners or operators of facilities that dischargeregulated effluents pursuant to this Act to secure apermit to discharge. The discharge permit shall be thelegal authorization granted by the Department todischarge wastewater: Provided, That the dischargepermit shall specify among others, the quantity andquality of effluent that said facilities are allowed todischarge into a particular water body, complianceschedule and monitoring requirement.124
WATER-RELATED DISEASES WATER BORNE WATER WASHED WATER BASED WATER INSECTRELATEDMethemoglobinemiaCholeraBotulismTyphoidHepatitis ADysenteryCryptosporidiosisMinamata DiseaseTrachomaEnterobiasisAscariasisTrichomoniasisTrichuriasisPediculosis/ScabiesSchistosomiasisChlonorchiasisFasciolopsiasisMalariaFilariasis
ECONOMIC CONSEQUENCES• Total economic losses 67B• Health P 3B• Fisheries Production P 17B• Tourism P 47B• Other economic losses• Damage claims• Family income due to desire for bottled water(4.6B per year, Metro Manila)Source: Philippine Environmental Monitor 2003 <<<BACK>>>
156THE NEED FOR WASTEWATERTREATMENT PROTECT RECEIVING WATERS FROMFAECAL CONTAMINATION PROTECT RECEIVING WATERS FROMOXYGEN DEPLETION AND ECOLOGICALDAMAGE PRODUCE MICROBIOLOGICALLY SAFEEFLLUENTS FOR AGRICULTURAL ANDAQUACULTURAL REUSE<<<BACK>>>
162Hazardous Solid Waste• waste that posesubstantial dangerimmediately or over aperiod of time to human,plant or animal life. Itexhibit the following:• Toxicity• Ignitability• Corrosivity• Reactivity<<<BACK>>>
164Healthcare waste Includes all the waste generated byhealth care establishments, researchfacilities and laboratories. Also includes the waste originatingfrom “minor” or “scattered” sourcessuch as that produced in the courseof health care undertaken in thehome (dialysis, insulin injectionsetc.)
165Health Impact ofHealth Care WasteCharacteristics: Contains infectious agents Genotoxic Contains toxic or hazardouschemicals or pharmaceuticals Radioactive Contains sharps<<<BACK>>>
166Types of Health Care Waste Infectious waste Pathological waste Sharps Pharmaceutical waste Genotoxic waste Chemical waste Waste with high content of heavy metals Pressurized containers Radioactive waste
167Health Impact ofHealth Care WastePersons at Risk All individuals exposed to hazardoushealth care waste are potentially at risk,including those within health careestablishments that generate hazardouswaste, and those outside these sourceswho either handle such waste or areexposed to it as a consequence of carelessmanagement E.g. MDs, nurses, healthcare auxiliaries,maintenance personnel, patients, visitors,waste disposal workers, scavengers
168Health Impact ofHealth Care Waste Hazards from Infectious Waste andSharps1. Through a puncture, abrasion, orcut in the skin2. Through the mucous membrane3. By inhalation4. By ingestion
170Health Impact ofHealth Care Waste Hazards from Chemical andPharmaceutical Waste- Intoxication – acute or chronic exposure,skin absorption, inhalation or ingestion- Injuries e.g. burns- Examples – disinfectants, obsoletepesticides, chemical/pharmaceuticalresidues discharged into the seweragesystem
171Health Impact ofHealth Care Waste Hazards from Genotoxic Waste- Exposure to genotoxic substancesmay occur during preparation of ortreatment with particulardrugs/chemicals- Example: antineoplastic drugs- Carcinogenic, mutagenic, secondaryneoplasia
172Health Impact ofHealth Care Waste Hazards from Radioactive Waste- The type of disease dependent ontype and extent of exposure- Headache, dizziness and vomiting tomore serious problems- Genotoxic- Severe injuries e.g. destruction oftissues which may lead toamputation
173Waste Management Plan for aHealth-care Establishment Location and organization of collection andstorage facilities Design Specifications of the bags, garbagecollection systems Required material and human resources Responsibilities of the different categoriesof personnel of the hospital including theattendants and ancillary staff Procedures and practices Training Program
175Treatment and Disposal Technologiesfor Health Care Waste Incineration – a high temperaturedry oxidation process that reducesorganic and combustible waste toinorganic, incombustible matter andresults in a very significant reductionof waste volume and weight. Thisprocess is chosen for wastes that cannot be recycled, reused or disposedof in a landfill site.
176Waste types not to beincinerated Pressurized gas containers Large amounts of reactive chemicalswastes Silver salts and photographic orradiographic wastes Halogenated plastics e.g. PVC Waste with high mercury or cadmiumcontent e.g. thermometers, used batteries Sealed ampoules containing heavy metals
177Characteristics of wastesuitable for incineration Low heating value Combustible matter – 60% Non-combustible solids – 5% Non-combustible fines – below 20% Moisture content – below 30%
179Treatment and Disposal Technologiesfor Health Care Waste Chemical Disinfection – chemicalsare added to waste to kill orinactivate the pathogens resulting todisinfection rather than sterilization.This process is suitable for treatingliquid waste such blood, urine, stoolsor hospital sewage. May alsodisinfect microbiological cultures,sharps etc.
180Treatment and Disposal Technologiesfor Health Care Waste Wet Thermal Treatmentbased on exposure of shredded infectiouswaste to high temperature, high pressuresteam and is similar to the autoclavesterilization process. It inactivates mosttypes of microorganisms. It is required forthe waste to be shredded beforetreatment, for sharps – milling orcrushing. It is not appropriate foranatomical waste and animal carcassesand will not sufficiently treat chemical andpharmaceutical wastes.
181Wet Thermal Treatment Disadvantages:- the shredder is liable to mechanicalfailure and breakdown- the efficiency of disinfection is verysensitive to the operationalconditions
182Treatment and Disposal Technologiesfor Health Care Waste Microwave Irradiationmost microorganisms are destroyedby action of microwaves of afrequency of 2450 MHz and awavelength of 12.24cm. Theinfectious agents are destroyed byheat conduction
183Hospital Hygiene andInfection Control Epidemiology of NosocomialInfections- transition from contamination toinfection- sources of infection- routes of transmission
184Hospital Hygiene andInfection Control Prevention of Nosocomial Infections- Principles:a. Separate the infection sourcefrom the rest of the hospitalb. Cut off any route of transmission
185Hospital Hygiene andInfection Control Prevention of Nosocomial Infections- Isolation of the infected patientsand standard precautions- Cleaning- Sterilization- Disinfection- Hand Hygiene
186• In Metro Manila alone about 6,000 tons ofgarbage is generated per day.• People living near solid waste dumpsites areconstantly exposed to smoke fromspontaneous combustion.• A separate study by Torres et. al. and Bacude.t al. 1994 reported that groundwater neardumpsites are contaminated .
187PUBLIC HEALTH SIGNIFICANCE• aesthetic problems(eyesores, odor)• clogging of sewers,drains & river• breeding place ofinsects & rodents• surface &groundwater pollution• contributes to airpollution
Most PreferableLeast PreferableRecycleReduceReusePreventDisposeRecoverTreatEnd ofPipeGreenProcurement4 Rs190Hierarchy of Solid Waste Management
193SOLID WASTE COMPOSITION (Metro Manila)Composition Percent• Paper and Cardboard 22.37• Food and Kitchen Waste 19.15• Textiles 7.41• Rubber and Leather 1.85• Plastics 12.38• Yard Waste 21.47• Other Combustibles 6.82• Metal 1.93• Glass 1.54• Screenings <12mm 4.66• Hazardous 0.41_____________________________________________________Source: PRRP, 1990
194FUNCTIONAL ELEMENTS OF SOLIDWASTE MANAGEMENTGENERATIONSTORAGECOLLECTIONDISPOSALPROCESSINGANDRECOVERYTRANSFERANDTRNSPORT
195• it is difficult to control & varies with individualvalues and behavior• waste reduction at source is important tominimize waste generation• waste generation vary daily, weekly,monthly, and seasonallyWASTE GENERATION
196WASTE GENERATION• generation rate usually peak duringChristmas and summer seasons• quantities of SW generated is important inselecting collection equipment, collectionroutes, and disposal facilities• quantity of SW is needed for planningregulatory purposes
1981. Source reduction & recycling• thru design, manufacture & packaging ofproducts and longer useful life• selective buying patterns & the reuse ofproducts and materials• reusable products instead instead ofdisposable (plates, towel, etc)• use products with greater durability &repairabilityFactors Affecting Waste Generation
199Factors Affecting Waste Generation2. Public attitude & legislation• significant reduction can be attained ifpeople are willing to change habits &lifestyles to conserve natural resources3. Geographic & physical factors• warmer climate tends to generate morewaste• seasons of the year <<<BACK>>>
200 Why do you think “storage” is important inwaste management? this can have a significant effect oncharacteristics of waste, public health andaesthetic conditions this is a critical step in solid wastemanagement segregation is the primary step in wastereduction and recyclingSTORAGE
2011. effects on waste components biological composition absorption of fluids2. types of containers to be used depends on characteristics & types of SWand frequency of collectionCONSIDERATIONS FOR WASTESTORAGE
202CONSIDERATIONS FOR WASTESTORAGE3. location of container depends on the type of dwelling orcommercial/industrial facilities, the availablespace, and access to collection services4. public health and aesthetics production of odor and unsightly conditions potential breeding site of rodents and insectsthat are vectors of diseases<<<BACK>>>
203 gathering and hauling of wastefrom collection points to disposalsite 50-70% of total cost of solid wastemanagement is spent for collection frequency of collection and type ofcollection vehicles are criticalconcernsCOLLECTION OF SOLID WASTE
204COLLECTION OF SOLID WASTE need for proper timing duringcollection separate collection system forhazardous waste training of solid waste collection crew
205COLLECTION ROUTES• identifying point and frequency ofcollection• routes should be laid out (route maps)• in hilly areas, start from top andproceed downhill• start from the farthest point towards thedisposal site• areas with large quantities of SWshould be served first <<<BACK>>>
206• this involves (1) transfer of waste fromsmaller collection vehicle to largertransport equipment (2) subsequenttransfer of waste to disposal site• transfer takes place in a transfer station• Transfer station is recommended ifdisposal site is relatively far (>15km)TRANSFER AND TRANSPORT
207TRANSFER AND TRANSPORT• smaller collection vehicles are used tomaneuver in city streets• further segregation can takes place inTS• waste are treated and compacted inTS<<<BACK>>>
208• involves recovery of separated materials,processing and transformation of solidwaste• facilities for SW separation andprocessing are: material recovery facility,transfer station, combustion facilities anddisposal site• processing includes separation of wastecomponents by size (screening),separation of metals (magnets),composting, and combustionPROCESSING AND RECOVERY
209PROCESSING AND RECOVERY transformation process includesvolume reduction and recovery ofconversion products and energy•biological process - composting•chemical process - combustionconversion to energy (RDF)<<<BACK>>>
210DISPOSAL remaining waste afterwaste reduction,recycling, reuse andprocessing should beproperly disposed most commondisposal is SanitaryLandfill safe and reliable long-term disposal of solidwaste is necessary
Solid Waste Disposal OptionsDisposal Advantages DisadvantagesSanitaryLandfillsMinimumEnvironmental Pollution(e.g., groundwaterpollution)ExpensiveComposting Compost as soilconditioner / fertilizerMust be marketableWaste sortingIncineration Reduction of waste toland disposalRequires min. areaExpensive
217Food Safety Food safety is non-negotiable Serving safe food is not an optionbut an obligation of foodestablishments, manufacturers andsuppliers. Customers must be assured thatthe food they eat is safe.
218Objectives of Food Sanitation To ensure the consumption of safe andwholesome food To prevent the sale of food offensive tothe purchaser, or inferior in value andquality To cut down spoilage and wastage offood
219Food Contaminants Modes of Transmission Classifications Effects
220Modes of Transmission of Food-borne DiseasesInfectedAnimalsDiseasesSusceptibleIndividualSick personCarrierCarelessindividualIntestinaldischargesOpen Wounds,Boils, AcnePimplesRespiratoryand OralDischargesAirDrinking WaterHandsInsects/RodentsUtensilsPoisonsFOODDeathDisability<<<BACK>>>
221Classification of Contaminants Chemical contaminants Physical contaminants Biological contaminants<<<BACK>>>
222Chemical Contaminants Toxic metals Food service chemicals Pesticides Additives and Preservatives
223Chemical ContaminantsChemical Toxin Source Associated FoodsToxic metals Utensils & equipmentcontaining toxic metals(i.e. copper, brass, zinc)High acid foods,carbonatedbeveragesFood servicechemicalsCleaning products,polishes, lubricants,sanitizersAll foodsPesticides Used in preparationareas to control rodentsand insectsAll foodsAdditives andPreservativesUsed to enhance tasteor prevent spoilageAll foods
224Chemical Food PoisoningChemicals SourceAntimony Food cooked in poorly coated or chipped enameledcooking utensilsCadmium Chilled acid foods or drinks allowed to stand incadmium-plated metal containersCyanide Silverware not properly washed and sanitized afterdetarnishingZinc Acid foods cooked in galvanized iron kettlesLead Improperly washed fresh fruits and vegetables sprayedwith lead; food or water that has been in contact withlead pipes, lead-plated equipment, and lead-solderedpots and pansArsenic Improperly washed fresh fruits and vegetables sprayedwith arsenicFluoride Food or drinks with sodium fluoride (used to get rid ofcockroaches)Methyl Chloride Leaking mechanical refrigerators <<<BACK>>>
225Physical Contaminants Results from the accidentalintroduction of foreign objectsinto the food
230Pathogen Transmission RoutesCross-contamination• Transfer of harmful substancesor microorganisms to food
231Pathogen Transmission Routes Cross-contaminationUnclean and unsanitized handsCleaning cloths and spongesFood contact surfacesRaw or contaminated foods<<<BACK>>>
232Effects of Food ContaminantsAdverse Health EffectsAdverse Non-Health Effects<<<NEXT>>>
233Food-Borne Illnesses (FBI) Food-Borne Infection• Results when pathogens grow in theintestines after a person eats foodcontaminated with them Food-Borne Intoxication• Caused by eating food containingpoisonous toxins
234Classification of Food-Borne Illnesses (FBI)Food-Borne IllnessesBacteria Typhoid Fever Cholera BacillaryDysentery SalmonellaInfection Other gastro-intestinaldiseasesParasitic Ascariasis Ameobiasis Trichinosis Giardiasis Balintidiasis OthersBacteria Staphylococcal Botulism (C.Botulinum) Streptococcal Bacillus cereusPlant orAnimal Somemushrooms Some mussels Certain herbs Some fishes OthersChemicalAccident Arsenic Lead Cadmium Cyanide Antimony Nitrites DDT, etc.Viral Hepatitis A Rotavirus OthersFood-BorneInfectionFood Poisoning orFood Intoxication
236Microbial Food-Borne AilmentsPathogen Time Frame for Onset of SymptomsCampylobacter 1 to 10 days (usually 3 to 5 days)Clostridiumbotulinum12 to 36 hoursE. Coli 0157:H7 1 to 10 days (usually 3 to 5 days)Hepatitis A 1 to 7 weeks (usually 25 days)Listeriamonocytogenes4 days to several weeksSalmonella 6 hours to 3 days (average 18 hours)Staphylococcusaureus2 to 7 hoursVibrio vulnificus 1 to 3 days<<<BACK>>>
237Adverse Non-Health Effects High Medical Expenses Lost work and reduced productivity Lost business and reputation Increased insurance premium Retraining costs<<<BACK>>>
239Basic Safe Food Handling Rules1. Clean: Wash hands and surfaces often2. Separate: Don’t cross contaminate3. Cook: Cook to safe temperatures4. Chill: Refrigerate promptly5. Buy goods at only approved/ reputablesources6. Implement an integrated pest managementprogram7. When in doubt, throw it out!
240Control of Chemical Hazards Pesticides Additives and Preservatives Toxic metals Food service chemicals
241Control of Physical Hazards Do not use glasses to scoopout ice. Use only commercialfood grade plastics or metalscoops with handles. Do not chill glasses or anyfood items in ice that will beused for drinks.
242Control of Physical Hazards Do not store toothpicks or non-edible garnishes on shelves abovefood storage or preparation areas. Clean can opener before and aftereach use.
243Control of Physical Hazards Place and maintain protective shields onlights over food storage and preparationareas. Remove staple wires, nails, and similarobjects from boxes and crates awayfrom food preparation areas.
244Control of Biological Hazards Factors Affecting Growth of Bacteria•Type of food•pH•Temperature•Moisture•Oxygen•Time
245Methods of Food Processing Dehydrating Heat treatment Freezing Fermenting and similar inhibitions ofmicrobial growth Irradiating with gamma ray’s highenergy electrons
246Spoilage of Canned Foods:Classification of Deteriorated Cans Pinholes Leaks Swells (swellers) Springer or flipperDents are entry points for microbes!
247Spoilage of Canned Foods:Classification of Deteriorated Cans Pinholes• Tiny holes caused by action of food acidsduring prolonged storage Leaks• Due to improper sealing• Due to brittle metal• Due to corrosion
248Spoilage of Canned Foods:Classification of Deteriorated Cans Swells (swellers)• Both ends of cans bulge outward,which do not yield to fingerpressure• Caused by the production of gas bymicroorganisms that are not killedbecause of inadequate sterilizationof contents or by infection throughleaks• Methane or hydrogen sulfide (H2S)
249Spoilage of Canned Foods:Classification of Deteriorated Cans Springer or flipper• A condition of the can where one endhas a bulge which may be transformedto the other end by pressing thebulging end
250Spoilage of Canned Foods:Classification of Deteriorated CansSevere angularly dentedcan with crimping of bodySevere dent that bucklesend seam of a can
251Control of Food Handlers Handwashing Personal Hygiene Practices Sick or Injured Food Handlers Hygienic Food Preparation Practices
253The Four-Hour Rule Principle stating that cooked proteinfoods that have been held attemperatures between 40F and 140F(4C and 60C) for more than 4 hourswill be considered unfit forconsumption and must be destroyed
254Essentials of Food EstablishmentSanitation Healthy food handlers who are aware ofand who put into practice sanitary andhygienic food handling techniques Safety of food and drinks• Health departments exercising vigilance• Lab and physical exams• Precautions in handling insecticides, ratpoisons and other poisonous materials Adequate lavatory, toilet facilities andchange areas
255Measures to Control and PreventFood-Borne Diseases in FoodEstablishments Protection of food at all times frominsects and vermin Employment of food handlers who arehygienic and free from infectious diseases Storage of food subject to infection attemperature 45F (7C) or 140F(60C)
257Four Sanitary Requirements ofEquipment Used in Food Processing1. Designed andconstructed to whollyprevent contaminationof the product both inprocess and thereafter2. Process applieduniformly andeffectively to the food
258Four Sanitary Requirements ofEquipment Used in Food Processing3. Made of materials andin shapes that are easilycleanable4. Foolproof and tamper-proof in assembly for allparts vital to theprocess and protectionof the product
259Physical Requirements of FoodEstablishments Orderly workflow patterns to controlsafety and quality at all critical points• Plan task to enable employees to travel at the leastdistance• Avoid difficult patterns that cause collisions, falls orspills• Have work spaces and equipment ready when food isbrought out of storage
260Physical Requirements of FoodEstablishments Surfaces (walls, floors and ceiling):durable, non-absorbent, smooth andreadily accessible for cleaning Kitchen floors: non-skid, repel liquids,withstand strong cleaners
261Physical Requirements of FoodEstablishments Cold storage forperishable foods Sanitary dishwashers Restrooms for customersand employees
263Physical Requirements of FoodEstablishments Potable drinking watersupply facilities Water-tight plumbingsystem for water supplyand wastewater disposal
264Physical Requirements of FoodEstablishments Adequate lighting andventilation Garbage disposal andvermin control system Separate rooms for eating
265Recommended Dining Room AreasNo. of Employees Area (sq. m.)4 or less 10.805 11.706 12.607 13.508 14.409 15.3010 16.20
PROVISION OF DRINKING WATERFACILITY*267No. of Employees No. of SDW Facility1 - 50 151 - 100 2101 - 150 3151 - 200 4201 - 250 5*Refers to faucet, fountain, dispenser or any other suitablemeans
REQUIREMENTS FOR DRINKINGWATER FACILITIES268• Should be available within 200 ft from anylocation of worker• At least one sanitary drinking fountain forevery 50 employees• No cross-connections between drinkingwater supply and supply for industrialprocesses• Label water sources that are not potable• Drinking water should be protected frombackflow (from industrial processes)
PROVISION OF SANITATIONFACILITIES269• TOILET FACILITIES• Located as far as practicable but not morethan 200 ft from working stations• Adequate lighting & ventilation• Walls & floors constructed of imperviousmaterials• Separate toilet for each gender• Self-closing door
270Recommended Number ofSanitary Toilet Facilities
PROVISION OF SANITATIONFACILITIES271• WASHING FACILITIES• lavatories• showers• one shower should be provided for every 10employees of each gender• change rooms: with storage facilities• clothes drying facilities
278Physical Requirements of FoodEstablishments Potable drinking watersupply facilities Water-tight plumbingsystem for water supplyand wastewater disposal
279Physical Requirements of FoodEstablishments Adequate lighting andventilation Garbage disposal andvermin control system Separate rooms for eating
280Recommended Dining Room AreasNo. of Employees Area (sq. m.)4 or less 10.805 11.706 12.607 13.508 14.409 15.3010 16.20
281Administrative Requirements Sanitary Permit• application/renewal of sanitary permitfiled with Local Health Office• sanitary inspector conducts aninspection prior to issuance of permit Health Certificates• required for all food handlers
PARASITES AMONG FOODHANDLERSIN A TERTIARY HOSPITALBLASTOCYSTIS HOMINIS - 40.6%ENDOLIMAX NANA - 20.3%ENTAMEBA COLI - 13.6%GIARDIA LAMBLIA - 1.7%COCCIDIA - 1.7%
285What is 5S 5S is a systematized approach to:– Organize work areas– Keep rules and standards– Maintain discipline 5S utilizes– Workplace organization– Work simplification techniques 5S practice– Develops positive attitude among workers– Cultivates an environment of efficiency, effectivenessand economy
2865SJapanese English FilipinoSeiriSeitonSeisoSeiketsuShitsukeSortSystematizeSweepSanitizeSelf-disciplineSuriinSinupinSimutinSiguruhin angkalinisanSariling kusa
2875S Philosophy Productivity comes from the elimination ofwaste It is necessary to attack the root cause ofa problem, not just the symptoms. Participation of everybody is required.
288The Practice of 5S GoodHousekeeping Seiri (Sort)– Take out unnecessary items and dispose. Seiton (Systematize)– Arrange necessary items in good order. Seiso (Sweep)– Clean your workplace Seiketsu (Sanitize)– Maintain a high standard of housekeeping Shitsuke (Self-discipline)– Do things spontaneously without being told orordered.
289Sort (Seiri) Remove unnecessary itemsand dispose them properly.– Make the work easy byeliminating obstacles.– Eliminate the need to take careof unnecessary items.– Provide no chance of beingdisturbed with unnecessaryitems.– Prevent accumulation ofunnecessary items.
290Systematize (Seiton) Arrange necessaryitems in good order.– Prevent loss and wasteof time.– Easy to find and pickup necessary items.– Ensure first-come-first-served basis.– Make production flowsmooth and workeasy.
291Sweep (Seiso) Clean your workplacecompletely.– Keep environmentalcondition as clean as thelevel necessary for theproducts.– Prevent deterioration ofmachinery and equipmentand make checking ofabnormalities easy.– Keep workplace safe andwork easy.
293Sanitize (Seiketsu) Maintain a high standard ofhousekeeping and workplaceorganization at all times.– Maintain cleanliness and orderliness.– Prevent misoperation.– Make it easy to find out abnormality.– Standardize good practices.
294Self-discipline (Shitsuke) Train people to follow goodhousekeeping rules autonomously.
295Hard 5S Refers to all facets of the workenvironment: individual workstation– Furniture - tables, shelves, drawers,conference room– Equipment - computers, typewriter, faxmachine, copier– Layout of desk and equipment
296Soft 5S Office policies and procedures Dress code Sharing of responsibilities Telephone etiquette
297Benefits of 5S Reduces cost to a minimum Ensures delivery on time Safe for people to work in Make employee morale high High productivity Produces quality products and services
5 Basic Methods of Control300 Physical (mechanical)-use of mechanicaldevices or physical forces use of traps; shooting with bullets, darts; catching;clubbing Chemical-use of rodenticides, insecticidesand larvicides use of poisons which may be clasified into: Contact poison Stomach poison Fumigants Sterilants
301 Biological-limiting factors that affect their growth andreproduction such as food, space for their habitat. use of living rat predator and disease agent Environmental-cleanliness of the premises, properbuilding construction and maintenance Elimination of food by proper garbage disposal and foodstorage Elimination of breeding places (harborage) by proper refusestorage, satisfactory housekeeping and proper design andconstruction of buildings Rat-proofing of buildings – special construction to preventrats from going under, through and over to the building. Health education and Information
303CONTROL OF FLIES Musca Domestica - house fly Carriers of many diseases:dysentery, cholera, typhoid,diarrhea, conjunctivitis Fannia scaleris – latrine fly Breed in excreta, in fermentingand decaying garbage Carry the same diseases as thehouse fly
304Habits and Characteristics Housefly does not bite; stable fly is a vicious biter Housefly is about ¼ inch long, mouse gray or buff incolor Male is smaller than female The body, including the legs is covered with hairs The sticky hairs of the legs hold germs It dissolves sugar by depositing saliva on it. It rests on a quiet spot to clean head and proboscis,to digest and to vomit and suck up its half digestedfood.
305Life Cycle of House Flieseggspupalarvaeadult<<<NEXT>>>
306Egg Oval, white bright bodies 1 mm length No. of eggs (1 single fly): 1000-3000 in clusters of100 to 150 at a time Ave. batches laid in a lifetime: 2-4 batches; Max: 20batches Hatch out in 8 hours at 29-32°C Factors affecting # of eggs produced: Available food supply Climatic conditions Natural enemies<<<BACK>>>
307Larvae Grayish or creamy white, segmented (like a worm),smooth cylindrical ½ inch long Move by alternately contracting and expanding theirbodies (legless) Larvae stage: 4-7 days Highly motile, burrow into a fermenting mass, feedvoraciously, grow rapidly Optimum temp for growth: 32°C; killed at 64°C End of larval stage: become restless, migrate tocooler dryer surroundings (e.g. loose soil, undersurfaces of stones and boards)<<<BACK>>>
308 Mahogany brown, barrel shaped,developed from larval coating 6 mm long Immobile for 3-6 daysPupa<<<BACK>>>
309 Emerging from puparium, newborn adult fly crawls tentativelyuntil its wings have expanded fully and hardened. Flights: max- 500 to 1000 meters; min- 200 to 300 meters; whencarried by wind – up to 21 km Same size as when it emerges from pupa Lays eggs from 2- 20 days after emergence Eggs are deposited by female fly into a dung or other materialwhere heat generated by fermentation facilitates hatching andwhere moisture prevents drying Eggs are deposited within 8 hours of fresh manure only Length of life: 1 monthAdult fly<<<BACK>>>
310Breeding Places Human and Animal Excreta Garbage Rubbish dumps containing organicwastes Ground where liquid wastes are spilled
311Transmission of Disease Fly transmits disease through the legsand the digestive system It voids its digestive tract while feedingwhich contaminates food Produces 15-30 vomit spots and fecaldeposits in 24 hours
312Control Measures: Basis of control measures: habits andcharacteristics of housefly Preferred breeding material: horse manure Other breeding materials: animal manure, humanexcreta, fermenting vegetable wastes Larvae temperature susceptibility: 43 to 46 °C Mature larvae migrate from breeding material priorto pupation Pupa develop at or beyond the borders of mass ofbreeding material
313Control Measures: Larvae or adult insect crawl through loosemanure or earth Adult flies are attracted to food by odor Flies soar toward light Flies rest on vertical surface or hangingobject
314Methods of disposal of manure1. Disposal by contract2. Disposal of manure as fertilizer3. Disposal by drying4. Disposal by composting5. Disposal by incineration
315Disposal by contract Collection and transport contracted tosanitation group with the following rules: Manure to be collected early in the morning All manure should be completely carriedaway Vehicles should not allow spillage
316Disposal of manure as fertilizer Thinly spread on ground to dry quicklyor flowed under if manure is wet
317Disposal by drying Only in dry climates; if areas become wet, itturns into breeding places. Requirements: Grounds tamped and cleared of vegetation Manure is spread in layer not over 1 to 2 inchesthick Drying time: 4 to 7 days Area required: 1.1 sq m per animal
318Disposal by composting Manure is closely packed in a heap Heat generated in composting will killlarvae
319Disposal by incineration Manure may be staked in longwindrows, sprayed with oil and burned If manure is dried it can be burnedwithout oil
320Chemicals as larvicides If manure will not be used as fertilizer: Crude oil Waste oil Kerosene 2% solution of cresolNote: DDT is not effective against larvae
321Chemicals as larvicides If manure will be used as fertilizer Borax solution Hellebore Iron sulfate
322Chemicals as larvicides In dirty garbage can, privies or otherbreeding areas: Aldrin Dieldrin Organophosphate compounds
323Methods of control of adult flies Residual treatment Outdoor space sprays Fly trapping Fly paper and fly wire Swatting Screening Note: these are temporary measures andshould not be as substitute for excreta,garbage and waste control
324Residual treatment Chemicals are applied on surfaces(walls, leaves, etc) Housefly readily develops resistance toorganochloride or organophosphorus Less responsive to carbamate anpyrethrum type materials
325Outdoor space sprays Chemicals used for space treatmentsare more effetive than for residual/larvicidal applications Chemicals used: malathion, ronnel,fenthion, dichlorvos Resmethrin emulsion is highly effectivein reducing fly populations
326Fly trapping Two parts of fly traps Bait chamber – lowerdarker part of traps intowhich flies are enticed bythe odor of bait Trap chamber – upperand lighter part and isconnected with the baitchamber by an aperturethrough which the fliescrawl toward the lightafter having fed on thebait Location of fly traps Near breeding places:manure piles, latrines,garbage cans and dumps Near kitchens, aroundentrances to buildings,food preparing/ servingareas Baits – need not be asource of nuisance Fermented baits containalcohol Mixture of cereals,molasses yeast andwater
327Fly paper and fly wire Flies may be caught on wires or strips ofpaper coated with a sticky preparation Fly wire: Wire fence or wires made into pieces 450 – 900mm long and bent into a hooklet at one end;several wires may be twisted together Fly paper: Prepared by applying a thin coat of hot glue in apan to strips of paper 450- 900 mm long and 25 to50 mm wide
328Swatting An accessory measure by can givegood results if used especially beforemeal is served
329Screening Does not reduce flies but is the mostimportant measure in preventing fliesfrom gaining access to food Use wire mesh of 16 wires to an inchto exclude flies; 18 mesh wire toexclude mosquitoes<<<BACK>>>
331Mosquitoes – general description Known agents ofdiseases such asmalaria, filariasisand dengue Annoying and causediscomfort Frequently breed inbackyards or nearhouses
332Characteristics Slender, delicate insects that havescales on their wings and long antennae Mouthparts- for piercing and sucking;male mosquitoes DO NOT bite Female mosquitoes feed on the nectarof flowers or juices from plants
333Characteristics Female mosquitoes of most species layeggs on the water surface, wither singlyor in rafts, according to species Eggs hatch into larvae, change intocomma-shaped pupae and turn intoadult mosquitoes Life cycle from egg to adult: about 1week under favorable conditions
336Anopheles minimus flavirostris Most dangerous malaria transmitter inthe Philippines Prefers to breed in flowing clear waterat moderate elevations Prefers animal blood to human blood Has a short life span<<<BACK>>>
337Aedes poecilus Vectors of filariasis or elephantiasis inthe Philippines Breeds in the axil of abaca and bananaplants<<<BACK>>>
338Culex quinquefasciatus Breeds in artificial containers, groundpools and sewage Common house mosquito in the tropics<<<BACK>>>
339Aedes aegypti Carrier of dengue fever and yellow fever Adult is medium sized, with silvery markings on thelegs, abdomen and thorax Wings are clear Bites only in the daytime or in artificial light and itspoint of attack is the ankle Breeds ion containers within human habitations orbusiness buildings Lays eggs singly in water; or preferably in wet areasnear the water margin Larvae hand at 45 degrees while breeding throughthe water surface and dive when disturbed Life cycle: 12 to 15 days<<<BACK>>>
340General control measures Actions directed at water managementare irrigation, drainage, and liquid wastedisposal Health education
341Control of Mosquito larvae Larviciding Filling lowlands that have stagnantwater, if these cannot be drained Eliminating household sources such asempty containers (cans, bottles, usedcar tires, etc) left open Repairing leaks or openings form septictanks, cesspools, etc
342Control of adult mosquitoes Fogging – if there is sudden rise in mosquitodensity Insecticides: Pyrethrum - immediate killing of adult mosquitoes,low residual effect DDT – residual killing over a period of time onsprayed surfaces; cheap and effective; seriouspublic health consequence<<<BACK>>>
344Cockroaches Capable of spreading germsmechanically Objectionable in households and foodestablishment Impart disagreeable odor and taste tofood which they contaminate with theirfeces and materials regurgitated whilesfeeding
345Characteristics Growth is influenced by temperature, humidity, andavailability of food Contaminate food by running over it since they maycarry some disease organisms on their legs Troublesome in establishments where food is stored,cooked or served Spoils food and leave a roachy odor and particles offilth Brown, brownish black or tan. Flat bodied and foul smelling Mainly active at night or in dark places during the day
347Control measures Good housekeeping Building should be kept in good repair Food should be kept well-protected an dstored in tight-fitting containers, left-overs should not be exposed Garbage should not be left in indoorsovernight<<<BACK>>>
349 important vectors of disease Transmit pathogenic organisms from rat toman such as typhus and the plague Immediate hosts to some species of dog androdent tapeworms which occasionally infestman Bites are annoying to ma n, pets andlivestock Serious nuisance to housekeepersPublic Health Significance
350 Rat flea – responsible for transmissionof endemic typhus Human flea – usually infests houses Dog and cat fleaTypes of fleas
351 Small, wingless insects with mouth parts fitfor piercing and sucking Bodies are flattened form side to side Move around easily among the body hair ofanimals and can leap several inches Eggs are laid on the animal an don the flooror bedding of the animal. These are hatchedin a few days into larvae on the debris on theground or cracks of the floor.Characteristics
352 Live in dust in cracks, under carpets,and in cat or dog bedding Lifespan: 2 to 3 months Adult fleas attached themselves to theanimal and feed on their blood
354 Outdoor control Chemical sprays Indoor control Thoroughly vacuum floors, carpet, furniture, crevices aroundbaseboards, cabinets and other infested areas at least everyother day, pet bedding. Throw away vacuum bag in a sealedplastic bag after use because fleas can develop inside. Larvae Salt or carbolic acid applied on places where larva develops malathion On animals Carbaryl on cats and dogs Commercial dog shampooControl measures<<<BACK>>>
356Public Health Significance Capable of harboring and transmitting certaindisease organisms Bite really pierces and is blood sucking Inject a fluid which causes itchiness andirritation implicated in diseases such as plague,anthrax and relapsing fever Feed upon poultry, mice, rats and otheranimals
357Characteristics Unfed bedbugs are very flat. Becomeelongated and swollen when fed Food: blood or warm-blooded animals(humans) Both male and female bedbugs suck blood Mouth forms a sharp beak or proboscis whichthey can thrust into the skin Can survive for 9 months without food Crawl feely to their victims from their hidingplace
358Characteristics Believed to be activiely migratory at times,traveling by their own power form room toroom, besides being carried in clothes andbedding Lifespan of mature bed bug: 6 to 8 months Lays 200 eggs at an average of 3 to 4 x a day(when food and temperature are favorable) Ovideposition occurs only at temperatureabove 21°C with ample food. At thistemperature, eggs are hatched in 6 to 17days
359Characteristics Young bedbugs feed at first opportunity Accumulated in piles, cracks ofbedsteads or in places where bedbugshide during daytime Adult bedbugs can resist temperaturebelow freezing Temperature of 0 to 4°C with fairly highhumidity – lethal to large numbers
360Control measures Chemical control Malathion Deltamethrin or Cyflouthrin Dichorvos (DDVP)<<<BACK>>>
365Norway Rat Also known as brown, house or sewer rat Most common and largest burrowing domestic rat Adult weight: 16 or more ounces Fur: coarse, reddish brown Body: heavy-set, blunt-nose Tail: bicolored, shorter than body and head Ears: small, close set Droppings: large capsule shaped Sexual maturity: attained in 3-5 months
366Norway Rat Gestation Period: 22 days average Length of life: 1 year average Young : 8-12 per litter Number of weaned: average of 20 per year perfemale Harborage: ground level, burrows in ground andunder foundations of buildings, rubbish dumps Range : frequently 100-150 feet Food and water: omnivorous; garbage meat, fish andcereal grains Daily requirements: ½ to 1 ounce dry food and ½ounce of water
368Roof Rat Also known as grey, black and climbing rat Agile climber and medium-sized domestic rat Adult weight: 8-12 ounces Fur: black to slate gray, tawny above and grayishblack below Body: slender, pointed nose Tail: single color, longer than body and head Ears: large and prominent Droppings: spindle-shaped Sexual maturity: attained in 3-5 months
369Roof Rat Gestation Period: 22 days average Length of life: 1 year average Young : 6-8 per litter Number of weaned: average of 20 per year perfemale Harborage: above ground level, indoors in attics,between walls, in enclosed spaces Range : frequently 100-150 feet Food and water: omnivorous; vegetables, fruits andcereal grains Daily requirements: ½ to 1 ounce dry food and ½ounce of water
370House Mouse Smallest among the domestic rodents Adult weight: ½ ounces Fur: dusky gray Body: small slender Tail: semi-naked, about as long as body andhead Ears: moderately large and prominent Droppings: small, rod-shaped Sexual maturity: attained in 1-1/2 months
371House Mouse Gestation Period: 19 days average Length of life: 1 year average Young : 5-6 per litter Number of weaned: average of 30-35 per year perfemale Harborage: any convenient, place in walls, cabinetsand furnitures Range : frequently 10-30 feet Food and water: omnivorous; prefers cereal grains Daily requirements: 1/10 ounce dry food and 1/20ounce of water
372General Rodent Control Methods Preventive (environmental control) Elimination of food by proper garbage disposaland food storage Elimination of breeding places (harborage) byproper refuse storage, satisfactory housekeepingand proper design and construction of buildings Rat-proofing of buildings – special construction toprevent rats from going under, through and over tothe building. Health education and information
373General Rodent Control Methods Suppressive Measures Physical – use of traps; shooting with bullets,darts; catching; clubbing Chemical – use of poisons which may be clasifiedinto: Contact poison Stomach poison Fumigants Sterilants Biological – use of living rat predator and diseaseagent<<<NEXT>>>
INDUSTRIAL POLLUTIONCONTROLVictorio B. Molina, CE.,SE.,MPHAssistant Professor, Department of Environmental and Occupational Health,College of Public Health UP Manila
INDUSTRIAL POLLUTIONCONTROLOUTLINEState of EnvironmentalPollutionDiseases Related toPollutionPollution Control Measures•Air Pollutants•Solid Wastes•Liquid Wastes
HEALTH AND ENVIRONMENTENVIRONMENTHEALTHCOMMUNITY ECONOMY
DISEASES RELATED TOPOLLUTION•Health burden of diseases attributable toenvironmental pollution : 11 to 42% of all causes•Equivalent to 47 to 294 million days ofhealthy life lost (DHLL)Source: PEHAS (WB-UP-DOH 1990)
What is bioaccumulation andbiomagnification ?Bioaccumulation - increase inconcentration of a pollutant from theenvironment to the first organism in afood chainBiomagnification - increase inconcentration of a pollutant from onelink in a food chain to another.
Industrialization Exports increased by250% from 1986 to1991 2,300 hectares per yearare converted toindustrialareas and humansettlements
MAJOR FORMS OF INDUSTRIAL WASTESCOMBUSTIBLEWASTESOLID WASTESSLUDGE &SLURRY WASTEWASTEWATERCombustionSuspension inAtmosphereSurface orSubsurfaceDisposalSuspensionand/orSolubilizationFiltration andDecantationAtmosphereLandWaterTYPES OFINDUSTIRAL WASTEMODE OF RELEASE ENVIRONMENT OFDISPOSAL SITEparticulatesGaseousPollutantsAddedWaterVolatilizationSolidResiduesLiquidWasteErosion,LeachingIrrigation,FloodingAtmosphericFallout,PrecipitationSuspensionby Winds,SublimationEvaporation,EscapeofGaseousPollutantsAtmosphericFallout,Precipitation
AIR POLLUTIONWhat is air pollution?It is the presence of one or more aircontaminants in sufficient quantities, ofsuch characteristics, and of suchduration as to threaten human, plant oranimal life or to property, or whichreasonably interferes with the comfortableenjoyment of life or property.
Why is air pollution a majorenvironmental and occupationalhealth problem ? We breathe approximately 6 liters ofair every minute 8,640 liters of air per day The total surface area of the air sacsof our lungs is as big as a tennis court
Major Sources of Air PollutionEmissions from vehicles Fuel combustion from coal fired power plantsIndustrial processes Burning of solid wastes
Effects Of Air Pollution1. Limited VisibilityNoon Morning
Effects Of Air Pollution2. Economic damage to property
Effects of Air Pollution3. Annoyance to human senses
Effects of Air Pollution4. Damage to health Eye irritation – specific effect of photochemicaloxidants, aldehydes and particulate matter Acute respiratory infection – increased riskamong young children Acute bronchitis – direct irritating effects ofSO2, soot and petrochemical pollution Chronic bronchitis – aggravation of cough orsputum Asthma – aggravation from respiratory irritation
Decreased lung functions Reduced exercise performance Exacerbation of symptoms with chronicobstructive pulmonary disease (COPD) Headache – carbon monoxide causingmore than 10% carboxyhaemoglobin Lead toxicity – add to body burden Deaths – fine particulate increasingmortality in heart and lung diseaseEffects of Air Pollution
Specific Health Effects of CommonAir Pollutants1. Particulates (PM10 and PM2.5)2. Sulfur dioxide3. Oxides of nitrogen4. Ozone5. Carbon monoxide6. Volatile organic compounds7. Trace metals
1. PARTICULATES Associated with elevated risk of mortalityand morbidity (cough & bronchitis) Every 10 ug/m3 increase of PM10 isestimated to cause 1% increase in CVDdeath (WHO, 1997) Can cause pneumoconiosis inoccupational setting DENR Standard: TSP=250 ug/m3PM10=150 ug/m3
2. SULFUR DIOXIDE Water-soluble irritant gas affecting upperrespiratory tract Cause bronco-constriction and asthmaattacks Can attach to particulates and tend todeposit deeply in the lungs Cause of “acid rain” DENR standard: 180 ug/m3 (24-hr ave)
3. OXIDES OF NITROGEN Increase lower respiratory tract infections Increase incidence asthma Impair host defenses in the respiratory tract Reduce capacity of lungs to clear particlesand bacteria DENR standard = 150 ug/m3 (24 hr ave.)
4. OZONE Highly reactive compound that irritatesairways in the lungs Interferes with host defense mechanisms Secondary pollutant Trigger asthma attacks Can cause headache and fatigue Generate lower and upper respiratorysymptoms WHO guideline: 100 ug/m3 (8 hr exposure)
5. CARBON MONOXIDE Odorless and colorless gas Slightly heavier than air Has 200-300x more affinity tohemoglobin than oxygen Normal amount of CO in blood is 1% DENR standard: 10mg/m3 (8 hr ave)
6. VOLATILE ORGANIC COMPOUNDS About 261 VOCs have been detected inambient air Can cause irritation of the respiratory tract Can trigger asthma attack Can cause headache May have toxic and neurological effects
7. TRACE METALS E.g., Pb, Cd, Hg May affect nervous and respiratory system May affect liver and skin Pb can cause nerve damage, learningdisabilities and neurobehavioral problems inchildren Every 10ug/dL increase in blood Pb levelsis associated with 1-5 point decrement in IQof exposed children
AIR EMISSIONS FROM MOBILE SOURCESIN METRO MANILA, (tons/year)1990 2001 AREATOG 100,954 (93.5) 190,531.34 5,162 (4.8)CO 572,626 (99.2) 948,192 525 (0.09)NOX 66,216 (82.69) 109,760 276 (0.35)SOX 10,350 (11.75) No Data 12 (0.02)TPM 13,220 (10.6) 48,465 102,286 (82)PM10 11,450 (16.3) No Data 51,042 (72.9)Source: EMB-DENR,1990
RULE OF 1000“…states that a pollutant releasedindoors is 1000 times more likely toreach peoples lungs than a pollutantreleased outdoors.”World Health Organization, 1997 In urban areas most people spend morethan 70% of their time indoors at work,at home, or at school.
Effects of Air Pollution5. Changes in the ecology of thenatural environmenta. Acid Rainb. Greenhouse effect / El Niñophenomenac. Depletion of Ozone Layer
Control of Air Pollution1. Dilute in the atmosphere2. Prevent formation3. Reduce the quantity4. Change the process or equipment5. Apply air-cleaning technologies
Control of Air PollutionDilute in the Atmosphere
Air-cleaning TechnologyMethods Mode of Operation Suitable forMechanicalcycloniccollectorsWhirling around in afunnel followed bygravitation into a funnel.Coarse particles; orecrushing; trapping flyashElectrostaticprecipitatorsGas stream passes acrosselectrically charged platesand then discharged intoa storage hamperSmall particles (size >1/10 m)Power plant,incinerators, smelter andpaper millsWetscrubbersWashing outcontaminantsRemoval of SO2, H2S,HCl, crushing andgrinding plantsFabric filters(bag houses)Principle of vacuumcleanerCement plants, ironfoundries, steel furnaces
Solid Wastes•are all the wastes arising from humanand animal activities that are normallysolid and that are discarded as uselessor unwanted.Three General Types1. Municipal - domestic, residential2. Industrial - industrial activities3. Hazardous - poses substantial danger
433Common Impurities Dissolved Impurities Suspended Impurities Living Matters Gases<<<NEXT>>>
434Common Impurities1. Dissolved Impurities– Dissolved inorganic matter Minerals leaching into groundwater leading tohardness, alkalinity and other mineral contents. Fertilizer runoff, mostly phosphates, nitrate andsulfates Industrial discharges of all kinds, especially frommetal finishing trade Salinity (principally chlorides) from sea water orsaline ground water intrusion
435– Dissolve organic matter Natural impurities from decay of vegetable andanimal matter Domestic waste, general biological debris anddecay products, soap, detergents, Industrial discharges from e.g. food processing andintensive agriculture, tanning, papermaking, andorganic chemical industry. Includes fats, oils andsolvents Residues of pesticidesCommon Impurities<<<BACK>>>
436 Suspended Impurities– Colloids (organic and inorganic) Inorganic colloids such as clay, and iron ormanganese oxides Natural organic macromolecules and particles Industrial wastes from e.g. china clay or paperprocessing A component of sewage solidsCommon Impurities
437 Suspended Impurities– Suspended inorganic Natural materials, mostly sand Industrial materials from coal washings, miningwastes, lime and other sludge, oxide dust, fly ash,flue washings, etc.– Suspended organic Plant and animal particles Industrial and domestic productsCommon Impurities<<<BACK>>>
438 Living Matter– Microorganisms Algae, viruses, protozoa, micro-fungi, etc. Occurrence is promoted by nutrients and favorablebreeding grounds e.g. domestic sewage Exposure to light promotes algal growth– Larger life Fish, worms, crustaceans, insect larvae, etc. Occur naturally and may breed in large numberswhere food is plentiful Aquatic plants, floating and rootedCommon Impurities<<<BACK>>>
439 Gases– Oxygen and carbon dioxide occur in all natural waters.– Some underground sources contain high CO2, a fewcontains H2S.– NH3 can result from biological decay from industrialdischarge– Cl2 is often dosed deliberately.– Algal growth removes CO2 and may raise O2 to super-saturation in daytimeCommon Impurities<<<BACK>>>
440General Methods ofWater TreatmentRemoval of suspended solids and color which maybe accomplished:– By sedimentation – or permitting water toremain quiescent in large settling basin so thatthe suspended solids may settle to the bottom.– By coagulation - or applying to the water certainchemicals called coagulants that produce aninsoluble gelatinous and flocculent precipitatewhich absorbs and entraps the suspended solidsin the water and thus hastens their sedimentation– By filtration – or passing the water through alayer of sand or other material that retains thesuspended solids.
441General Methods ofWater TreatmentRemoval of bacteria which is accomplished by:– generally by the process mentioned for theremoval of suspended solids– supplemented by final disinfection with chlorineor other acceptable physical or chemical agentsto ensure the destruction of bacteria that maycause disease.
443General Methods ofWater TreatmentRemoval or neutralization of tastes, odors,objectionable minerals and dissolved gaseswhich is accomplished– By aeration, or exposing the water in thin filmsor droplets to the oxygen of the atmosphere– By treating the water with certain chemicals(eg., CuSO4 to control algae)– Using activated carbon.
444General Methods ofWater TreatmentRemoval of hardness, which is generallyknown as softening and is accomplished : Ion exchange By membrane filtration such as reverseosmosis, or nano filtration
Water Treatment Tech Sept2010 445Thank youand Good Day!
451 Water Treatment TechSept2010Factors affecting theEffectiveness of Disinfection Duration of contact between the disinfectingagent and the pathogens Nature and concentration of microorganisms /pathogens Dosage or strength of disinfecting agent Characteristic or condition of water duringdisinfection
452 Water Treatment TechSept2010Conditions for EffectiveDisinfection Low suspended solids ( 1 mg/L) – suspendedsolids may prevent the action of disinfectingagents with the pathogens Low organic matter and other oxidizablesubstances – may react with disinfectantsthereby reducing the effect the disinfectingagents with the pathogens.
Chlorination Properties of Chlorine– Chlorine is a poisonous, corrosive, greenish-yellow gas that has a sharp, suffocating odorand is 2 ½ times heavier than air. It is veryirritating to the mucous lining of the lungs, andits inhalation in large quantities may be fatal. Commercial Preparation of chlorine– Liquid Chlorine– Chlorine Gas– High Test Hypochlorite (HTH), granular– Bleaching Agent, NaOCl <<<BACK>>>
457 Water Treatment TechSept2010Ozonation Ozone is a naturally occurring component of fresh air. The ultra-violet rays of the sun reacting with the Earthsupper atmosphere, which creates a protective ozone layer,can produce it; or it can be created artificially with an ozonegenerator. The ozone molecule contains three oxygen atoms whereasthe oxygen molecule contains only two. Ozone is a veryreactive and unstable gas with a short half-life before itreverts back to oxygen. Ozone is the most powerful and rapid acting oxidizerproduced, and will oxidize all bacteria, mold and yeastspores, organic material and viruses
459 Water Treatment TechSept2010Application of Ozone Ozone is a strong oxidizing agent that can be used asdisinfectant Color removal Taste and odor removal Turbidity reduction Organics removal Microflocculation Iron and manganese oxidation Bacterial disinfection and viral inactivation
461 Water Treatment TechSept2010Effect of Ozone on Indicatorand PathogenicMicroorganisms Ozone is much more powerful oxidant thanchlorine Ozone concentration to inactivate:– 99.9% enteric viruses: 0.05 to 0.6 mg/L– 99.99% cryptosporidium oocysts: 1.1 mg/L– G. lamblia: 0.5 mg/L
Effect of Ozone on BacterialCellBacteria in Solution Ozone nears bacteria Ozone bonds withorganic cpds in cell wallThe free radical of ozonebreaks bonds in cell wallsOzone destroys integrityof cell wallO3 kills bacteria, releaseorganics
463 Water Treatment TechSept2010Ozone Generation Corona discharge principle:– Properly dried air, or oxygen itself is passedbetween a high-voltage electrode and aground electrode separated by a dielectricmaterial– In excess of 80% of the applied energy isconverted to heat that, if not rapidlyremoved, cause ozone to decompose
464 Water Treatment TechSept2010Generation of Ozone
466 Water Treatment TechSept2010Ultraviolet Radiation Oxidizing and germ-killing effect Ultraviolet radiation of water in the presence ofoxygen from the air appears to be the most naturalpurification and disinfection principle Inactivates pathogens by destroying the DNA thuspreventing replication
467 Water Treatment TechSept2010Ultraviolet Radiation Most sensitive to UV radiation are viruses andbacteria in vegetative forms, such as, Salmonellatyphosa, Vibrio cholerae, Shigella dysenteriae,Hepatitis virus and Mycobacterium tuberculosis. At higher doses, UV radiation can inactivateLamblia cysts and cryptosporidium oocysts. Spores could be resistant to UV radiation, thushigher doses are required to destroy them.
468Water Treatment Tech Sept2010UV Generators Germicidal lamp that converts electrical power intoUV-C<<<BACK>>>
472 Water Treatment TechSept2010Definition of Terms Feed – solution which enters the system and ispressurized Permeate – solution (usually purified water) whichpasses through the membrane and is collected foruse Concentrate (brine, retentate) – the solution, whichexists from the system, that has not passed throughthe membrane. It is enriched in particular rejectedmaterial
473 Water Treatment TechSept2010Applications of MembraneFiltration Suitable for removal of particulates from pre-treatedwater in the range of 0.1 to 100 µm provided thatthe total suspended solids do not exceed 100 ppm
474 Water Treatment TechSept2010Reverse OsmosisReverse Osmosis (RO)– pressure-driven process that retains virtuallyall ions and passes water.– The pressure applied exceeds the osmoticpressure of the salt solution against asemipermeable membrane and leaving saltsbehind.
484 Water Treatment TechSept2010Ultrafiltration Ultrafiltration is the process that uses semi-permeable membranes to separatemacromolecules in a solution.
485 Water Treatment TechSept2010Features of Ultrafiltration Size and molecular shape of solute areimportant factors in retention. UF membranes have much looser porestructure than RO membranes The degree of rejection of solute depends onmolecular weight cutoff (MWC) and themolecular weight of the solute
486 Water Treatment TechSept2010Membrane Properties UF membranes are available in CelluloseAcetate, polysulfone, acrylic and othernoncellulosic polymers UF membranes have been prepared frompolymers such as polycarbonate, polyvinylchloride, polyamides, polyvinyl fluoride
UF System applications Municipal water treatment plants of both surfaceand groundwater supplies Can remove total organic carbon, trihalomethaneand color NF membranes exhibit as high as 40% rejection ofsalts<<<BACK>>>
489 Water Treatment TechSept2010Nanofiltration (NF)Characteristics of NF Water softening using low-pressure ROmembranes Softening and organics removalaccomplished on low TDS and slightlybrackish water Molecular Wt Cutoff (MWC) membranesvary from less than 200 to 500 asopposed to tight RO membranes that
490 Water Treatment TechSept2010Process Performance andSelection Among 3 MembraneProcessesReverse Osmosis (RO)– Effectively removes most organics, bacterial andparticulate matter from water– Removes inorganic contaminants with ratesranging from 60 to 99%
491 Water Treatment TechSept2010 Nanofiltration (NF)– Rejects hardness, repel bacteria and virus andremove organic-related color without generatingundesirable chemical compounds such aschlorinated hydrocarbons– Applied to low-TDS water for softening and organicremoval Ultrafiltration (UF)– Applied to municipal systems– Removes organic contaminants<<<BACK>>>
492 Water Treatment TechSept2010DISTILLATIONDistillation Process When water is heated to boiling point it ischanged to gas, leaving behind the non-volatileimpurities When water vapor is cooled, it is changed oncemore to water, which is now free fromdissolved and undissolved non-volatile matter.
493 Water Treatment TechSept2010Impurities Removed byDistillation– Distillation process removes almost all impuritiesfrom water.– For removal of microorganisms, nitrate, sodium,hardness, dissolved solids, most organiccompounds, heavy metals, and radionuclides– Removes about 99.5 percent of the impuritiesfrom the original water
494 Water Treatment TechSept2010Impurities that are Not Removed– Distillation process may retain 0.3 to 0.5 percentof water impurities after treatment– Not removed:Some volatile organic contaminants (VOCs)Certain pesticides and volatile solvents– Bacteria may re-colonizes on the cooling coilsduring inactive periods
496 Water Treatment TechSept2010Uses of Distillation– Small scale application in laboratories– Preparation of purified water in pharmacy forinjection– Production of potable from sea and brackishwater
497 Water Treatment TechSept2010Treated Water Quality– Distillation removes with certainty any organism(bacteria, viruses, etc) from feedwater.– Theoretically, it removes all non-volatile matter.– In practice, carryover of dissolved and colloidalmatter into distillate takes placeE.g. Carbon dioxide, ammonium
Water Treatment Tech Sept2010 501WATER SOFTENINGUsing Ion Exchange ProcessIon Exchange ProcessA process by which one type of ion contained inwater is absorbed into an insoluble solid materialand replaced by an equivalent quantity of anotherion in the same chargeWhen resin has reached saturation (exhaustion), itis rendered operative again by regeneration.
502 Water Treatment TechSept2010Problems caused by Hard Water– Interferes with all types of cleaning tasks– Dishes and glassware washed withhardwater may be spotted when dry.– Causes films on glass shower doors, wallsand bath tubs– Hair washed in hardwater may feel stickyand look dull– Scale build up in hot water heater– Scale deposits corrode and clog plumbingfixtures
504 Water Treatment TechSept2010 Uses:– For upgrading municipal or private watersources in industry– Water softening– Purification of boiler needsIon-Exchange Process
Water Treatment Tech Sept2010 508ACTIVATED CARBONFILTRATION
509 Water Treatment TechSept2010Impurities removed byActivated Carbon (AC) Filters– Organic Chemicals that causeTaste, Odor, Color problems, Mutagenecity,Toxicity– Chlorine and chlorination by-products– Inorganic such as arsenic, chromium, mercury– Pesticides and Solvents– Polychlorinated biphenyls– Polycyclic aromatic hydrocarbons– Radon
510 Water Treatment TechSept2010Impurities not removed byAC Filtration– Microbes– Sodium– Nitrates– Fluoride– Hardness– Lead and other heavy metals are removedonly by specific types of AC filter
515 Water Treatment TechSept2010Exposure Time The process of adsorption is influenced by thelength of time that AC is in contact withcontaminants in water. Increasing in contact time allows greater amount ofcontamination to be removed.
Effects on Bacteria AC filters can be breeding ground for bacteria Organic chemicals are sources of food forvarious types of bacteria Pathogenic bacteria may cause illnesses tohuman such as typhoid, cholera, dysentery. Separate system to treat water for pathogensmust be applied.<<<BACK>>>