CPHM FINALS (environmental health

• ENVIRONMENTAL HEALTH

  • branch of publ health devoted to prevent illness thru managing env & changing ppl’s behavior to reduce exposure to biological agents of disease & injury (aspects of human health: quali of life determine by physical)
  • practice covers the assessment, correction, ctrl & prevention of env’al elements that can adversely affect the human health
• ENVIRONMENTAL HEALTH

  What Problems Do We Face?

  Traditional Hazard

  • related to poverty & insufficient development
  • TB -Schistosomiasis -Malaria -Dengue - Filariasis

  Modern Hazard

  • related to rapid dev that lack of health & env safeguards

  CD:

  • SARS/COVID-19
  • Avian Flu -Diabetes
  • HIV/AIDS

  NCD:

  • HPN
  • Diabetes
  • COPD (chronic obstructive pulmonary disease)
• Environmental Sanitation

  • the ctrl of every factors in the physical env such as water. Air, soil, excetal & food as well as insect/ rodent. Chemical, solid & liquid wastes w/c have a sig effect on the physical dev, health & survival

  Importance of env sanitation:

  • Promotes health
  • Prevents disease transmission
  • Eliminates breeding places of insects & rodents that carry germs Improves qual of life
  • Protects env from pollu
• The Code on SANITATION of the PH (Presidential Decree No. 856)

  • The ultimate obj is to improve the way of Filos by directing publ health services towards the protection & promotion of the health of our ppl

  Goal of Env Sanitation

  • Water sanitation
  • Food sanitation
  • Community waste mngmt
  • Rodent ctrl
  • Vector ctrl
  • Air pollu ctrl Occupational health
  • Radiologic health
  • Sanitary housing
  • Disaster mngmt
• Water Supply & Sanitation

  • is a prime necessity & a basic need for existence (ppl survv w/o food but not ater even if bdy contains 60% water)
  • used for drinking, bathing, cooking, washing & maintaining general cleanliness in & around house
  • is one of the top priority acts in the field of env’al sanitation (by sanitation inspector)
• Types of Water Supply

  Lvl I (Point Source)

  • a protected well (shallow & deep well/ developed spring/rainwater) w/ an outlet but w/o a distribution system
  • normally serves around 15-25 households
  • the farthest user is not more than 250m from point source

  Lvl II (Communal Faucet Syst/Stand Posts)

  • syst composed of a source, a reservoir, a piped distribution network & a communal faucet located not more than 25m from the farthest house
  • generally, suitable for rural & urban areas whr houses are clustered densely populated areas
  • usually, 1 faucet serves 4-6 households
• Types of Water Supply

  Lvl III (Waterworks System)

  • syst w/ a source, transmission pipes, a reservoir & a piped distribution network for household taps
  • generally suited for densely populated areas
  • ex. MWSS, Maynilad, Maynilad Water
  • *Lvl III syst may include a lvl I syst w/ piped distribution network for household taps

  →Doubtful Sources

  1. Undeveloped springs (may contain pathogens)

  2. Open dug wells (no protective covering)
• Sources of Water Contamination

  • Location of toilet
  • Poor sanitary practices
  • Failure to clean water tanks
  • Illegal connection to pipes
  • Leaking pipes
  • Failure to protect water wells
  • Poor drainage of excess water
  • Bathing & washing near the source
• Types of Water

  Potable water

  • safe, clean, free from contaminants & pollu, reco for drinking purposes & food prep

  Polluted water

  • water w/c has suffered impairment on its physical qualities

  Contaminated water

  • -contains infectious agents, materials & toxic or poisonous substances, condemned for drinking purposes
• Types of Water according to source

  Rainwater

  • source of all freshwater, distilled pure water w/c may get contaminated at atmosphere during collection & storage

  Surface water

  • natural flow of water above ground including rivers, lakes, springs & streams

  Underground water

  • below the layers of the earth usually clean & safe except when located near the source of pollu (ex septic tank)

  Piped water

  • distribution to houses by means of pipes usually treated
• Impurities in Water (contaminants includes dissolved & suspended subst. that contri in cloudiness & turbidity in water)

  Physical impurities

  • inert suspension of floating substances that are carried by water that causes cloudiness/turbidity

  Chemical impurities

  • dissolved constituents of water w/c account mostly for the color of water

  Biologic/Bacteriologic impurities

  • include microscopic plants & animals other than bact present in water

  Radiologic impurities

  • results of nuclear weapon testing & discharge of radioisotopes & other radioactive wastes into water courses
• Examinations of Water

  Physical exam tests (physical attributes of water)

  Turbidity

  • degree of cloudiness/muddiness

  Color

  • due to presence of colored subst in solution (ex. vegetable matter & Fe salts)

  Odor

  • should be absent/very faint to be accepted for drinking d.

  Taste

  • algae, decomposing organic matter, dissolved gases & phenolic subst may cause taste
• Examinations of Water

  Chemical exam

  Hardness/Softness

  • due to Ca/Mg; has a laxative effect; causes scaling in boilers, pots & kettles

  pH (alkalinity/acidity)

  • acidic water is corrosive to metallic piping syst & alkaline water has a laxative effect

  Organic nitrogen

  • A constituent of all waste protein products from sewage, kitchen waste & all dead organic matter
  • Increased content should be suspected of possible contaminants
• Examinations of water

  Toxic substances

  • If present in appreciable concent is hazardous to human health
  • Includes arsenic, cadmium, chromium, lead, mercury, etc.
• Examinations of water

  Microbiological Examination

  • MOs in drinking water must not be present
  • water contaminated by sewage or by human & animal excreta can cause an epidemic water borne disease (diarrhea (typhoid, dysentry, cholera, etc))

  2 basic methods of Bacteriologic Exam

  1. Multiple Tube Fermentation - test for coliform - E. Coli: index of fecal contamination & serves as an indicator grp in bacteriologic analysis of water
  2. Membrane Filtration Method/ Standard Plate Count ~used for enumerating coliforms or the total viable popu of bact present in sample
• Methods of treatment of Water

  1. Filtration/straining- used of cloth/filters to filter water impurities
  2. Boiling of water for at least 2-5 mins
  3. Chemical disinfection- chlorination
• Other treatment methods

  Aeration

  • process whereby water particles are brought into intimate contact w/ air for the purpose of affecting the exchange of gas; peculiar taste & odor are removed

  Softening

  • method of removing Ca & Mg salts w/c affect the qual of water

  Fluoridation

  • treatment process aimed at preventing dental carries or tooth decay esp among children

  Coagulation/sedimentation w/ chemicals in setting basin

  Used of physical disinfectants like heat & radiation

  Contact treatment

  • removal of taste, odor, color of water by the use of activated charcoal as absorbent
• Methods of treatment of Water

  Food Sanitation

  Publ Health Importance of Food:

  Nutrition

  • food provides essential nutrients needed by our body

  Disease

  • food serves as vehicle/reservoir for food-borne diseases

  Food-borne infection

  • caused by living organisms (ex bact & parasite) entering body w/ food as vehicle for transmission

  Food borne/intoxication

  • myb caused by bact toxins/chemicals, may also be naturally occurring poisons present in plants, mushroom, fishes & spoiled foods
• Terms associated w/ Food Sanitation

  Food Control

  PURE FOODS LAW

  • this law ensures safety of foods & safeguard against adulteration & misbranding of processed foods as to qual, quantity & source

  Food Management

  • gov nutrition policies ascertaining the amnts of nutrients needed by popu to be fed

  i. Formulation & promotion of food production goals

  ii. Increasing efficiency of marketing food

  iii. Educ in nutrition & food values

  iv. Improvement of social distribution of food

  v. improvement & conservation of nutritive values of food
• Terms associated w/ Food Sanitation

  Food Technology

  • the economic application of laws & processes of biology, physics, chemistry & engr’ing in the prep & preservation of food products

  Food Handlers

  • ppl who handle food. Not only those who cook & serve in publ eating & drinking est but also include indvs in far off places (ex milker on the farm & those processing of foods)
• →Four Rights in Food Safety

  1.Right Sources

  ● Always buy fresh meat

  ● Always look at the expiry date

  ● Avoid buying canned foods w/ dents, bulges & broken seals

  
  

  2. Right Preparation

  3. Right Cooking

  4. Right Storage
• Methods of Food Preservation

  Refrigeration

  • low temp (0-4C) prevents bacterial action. Natural flavor myb maintained

  Drying

  • removes moisture from food stuff essential for bact growth & multipl’tion since bact need water/moisture to live & multiple so drying will kill the bact

  Salting

  • addition of relatively large amnt of common table salts to preserve food. Salt is bacteriostatic

  Pickling/souring - using weak acid

  Sugaring

  • storage of foods in syrup containing more than abt 50% sugar as sucrose/dextrose
• Methods of Food Preservation

  Smoking

  • rapid drying over smoke. The preserving action come from some preservatives in the smoke. Usually done in meat & fish

  Canning & Sterilization- cooking & preserving in airtight tin cans
• Food may be altered as follows:

  Mixing- if any substance has been mixed or added so as to increase the quantity but lowers the quality

  Substitution- fraudulent substi of cheaper article

  Subtraction of valuable constituents

  Concealing inferiority

  Addition of adulterants

  Misbranding- imitation, mislabeling

  Foods from sick animals or contaminated vegs.
• Community Waste Management

  • Waste materials consist of human excreta, garbage, refuse & industrial waste

  REFUSE

  • solid & semi-solid waste material other than human excreta & divided into 3

  Garbage

  • Solid wastes resulting from processing, preparation, & consumption of foods (ex left over vegetables, animals & fish materials)

  Public health importance:

  • serve as breeding place of flies & oth. Insects
  • harborage of rats & other vermin
  • offensive odor
  • garbage fed to hogs (lessen waste)
• Community Waste Management

  Rubbish

  Combustible (materials)

  • discarded furniture(wood), paper, yard trimmings. Considered as fire hazard

  Non-combustible

  • tin cans, ceramic, glass waste, metals. Breeding places of mosquitoes & other insects, can cause wound injuries

  Ashes

  ● Left over from burning wood/charcoal

  ● Irritant to eyes & nose
• Types of Waste Acc to Use

  Household waste

  ~Biodegradable - waste that can decompose in soil after a long period of time

  ~Non-biodegradable - do not decompose in soil

  Hazardous waste

  Also known as industrial waste

  imm & long-term risk to man, animals, plants, & environment

  any discarded solid/liq that:

  ● Contain carcinogenic compounds

  ● Catches fire easily (gasoline tinners)

  ● Reactive/unstable enough to explode or release toxic fumes
• 3 Basic Methods of Refuse Disposal

  1. Storage- adequate size w/ cover (if open, bcme breeding places of vectors nd inse)
  2. Collection- at least once a day w/ total coverage (min; once a wk)
  3. Final disposal (grbge coll/ grbge unit)
• Proper Excreta and Sewage Disposal

  EXCRETA- feces, urine & discharges from nose & skin

  SEWAGE- water w/ discharge of human body tog w/ liq waste from households & factory

  Related Diseases:

  Bact Infec- typhoid, cholera, bacillary dysentery, gastro-enteritis Viral infec- infectious hepa, poliomyelitis

  Protozoan infec- amoebiasis

  Helminthic inflec- ascaris, hookworm, schistosomiasis

  Mode of Transmission (excreta-related disease)

  ~water ~soil ~arthropods ~hands
• How to Control Transmission

  1. Proper excreta disposal
  2. Treatment of wastewater prior to discharge
  3. Good personal hygiene
  4. Proper food handling/storage
  5. Water disinfection
  6. Eliminate breeding place of insects
  7. Treatment of infected indvs (deworming)
  8. Health education
• Household w/ Sanitary Toilet

  • Households w/ flush toilets connected to septic tanks &/or sewerage syst or any another approved treatment syst, sanitary pit or ventilated improved pit latrine
  • Toilet

  Sanitary Toilet - approved type of toilet used for receiving & disposing human waste

  Unsanitary Toilet - Type of facility used for receiving & disposing human waste w/c dont fall under category
• Lvls of Toilet Use

  Indv Household Toilet -an excreta disposal syst that serves a single dwelling unit

  Shared Toilet -excreta disposal syst used by 2-3 households (10-15 indvs)

  Communal Excreta Disposal System -serves a grp of dwelling toilet facility shared by 2 or more households

  Public Toilet -a toilet facility located at public spaces like markets & bus stations (intended 4 public use)

  School -toilet facility located in a school essentially for use of students
• Approved Type of Toilet Facilities

  Type I

  • Non-water carriage toilet facility requiring no water to wash excreta into the receiving space/pit (ex ventilated improved pit latrine, sanitary pit privy)
  • Toilet facilities requiring small amnt of water (ex pour-flush toilets)

  *Ventilated Improved Pit (VIP) Latrine

  • an on-site toilet facility wherein pit receives excreta directly from the user & therefore dont require water for flushing; it comprises a lined pit, vent pipe w/ a fly screen, cover slab & a superstructure w/c allows entry of fresh air into the pit
• Approved Type of Toilet Facilities

  Type II

  • Water carriage type having a pour-flush or flush-type toilet facility & a septic vault/tanks as the disposal facility

  *Pour-Flush Toilet w/ Septic Tank

  • has a bowl w/ a water-seal trap. It’s as hygienic as the conventional tank-flush toilet & requires only small vol of water for flushing
• Type III

  • Water carriage type w/ pour-flush type toilet facilities connected to septic tanks/or to sewerage system to treatment plants

  Unapproved Type of Toilet Facilities

  Pit Latrine/Open Pit Privy

  • A pit of at least the same dimension as the sanitary pit privy, provided w/ pit flooring, w/ or w/o riser & seat & w/o cover to protect from flies & rodents

  Overhung

  • Struc provided w/ flooring & w/ an opening built above body of water or above ground w/o pit under it, used for defecation/disposal of human waste. It may be a part of house or a separate struc outside of house
• The Code on SANITATION of the PH (Presidential Decree No. 856)
• Approved Type of Toilet Facilities

  Rodent Control

  →Public health importance:

  ● Rodent cause harm by serving as:

  Disease transmission- rats can be source or reservoir of infec (ex plague, leptospirosis, rat bite fever, marine typhus, salmonellosis)

  Food Damage

  Material Damage
• Approved Type of Toilet Facilities

  Characteristics of rat:

  Habits are motivated

  • forms of motivation: food, water, shelter, sex

  Well-developed special sense

  • good tactile sensation (touch) coz of whiskers, good sense of smell but poor eyesight

  Prolific

  • reproduce rapidly w/ a period of gestation of 25 days, 6-14 times a yr, adult at 3 mos
• Characteristics of rat

  Food habits

  • tend to bring food to nest & share w/ others

  Have nocturnal habit

  • sleep at daytime & active at night

  Teeth w/ prominent incisors w/o canine teeth

  • only the front portion of incisors are covered w/ enamel, so they keep growing & become pointed to prevent this, they gnaw & destroy
• Rodent Control:

  Prevention & Control Measures

  Temporary:

  • Mechanical ways -use of traps, manual killing
  • Fumigation & poisoning

  Permanent:

  • Rat proofing structure
  • Environmental sanitation
  • Cleanliness & proper waste disposal