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The Environment and Human Health Two types of Environment

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					The Environment and Human Health


Two types of Environment:
     Natural Environment
- encompasses all living and non-living things occurring naturally on Earth.

           Built Environment
- refers to the man-made surroundings that provide the setting for human activity.

Environmental factors which affect human health:

    AIR QUALITY- is defined as a measure of the condition of air relative to the requirements of one or
    more biotic species and or to any human need or purpose.

    Most common Air Pollutants:




    a) Carbon Dioxide and Methane

    Carbon Dioxide (CO2) – a colorless, odorless non-toxic greenhouse gas associated with ocean
    acidification, emitted from sources such as combustion, cement production, and respiration.
Methane (CH4) – a non-toxic greenhouse gas but is extremely flammable and may form explosive
mixtures with air.

Health Effects:
 CO2 and CH4 contribute to enhanced global warming which affects human health.
 Methane is an asphyxiant gas

b) Particulate Matter - consists of a complex mixture of solid and liquid particles of organic and
   inorganic substances suspended in the air

Major Components of PM:
 Sulfate                                                   Sodium Chloride
 Nitrate                                                   Carbon
 Ammonia                                                   Mineral dust and water

Two Classifications of PM:
 PM10 - particles with aerodynamic diameter of 10 µm
 PM2.5 - particles with aerodynamic diameter of 2.5 µm

Health Effects:
 contributes to the risk of developing cardiovascular and respiratory diseases, as well as of lung
   cancer.

c) Chlorofluorocarbon (CFC) - is an organic compound that contains carbon, chlorine and fluorine,
   produced as a volatile derivative of methane and ethane.

Health Effects:
 Overexposure may cause dizziness, loss of concentration, Central Nervous System depression
   and cardiac arrhythmia.
 It can cause asphyxiation in confined spaces

d) Sulfur Dioxide (SO2) - a colorless gas with a sharp odor and is produced from the burning of
   fossil fuels and the smelting of mineral ores that contain sulfur.

Health Effects:
    can affect the respiratory system and the functions of the lungs causes irritation of the eyes.
    causes coughing, mucus secretion, aggravation of asthma and chronic bronchitis.

e) Ozone (O3) - formed by the reaction with sunlight of pollutants such as nitrogen oxides and
   volatile organic compounds.

Health Effects:
    can cause breathing problems, trigger asthma, reduce lung function and cause lung diseases.

f) Nitrogen Dioxide (NO2) - a reddish brown gas with a pungent and irritating odor. It transforms in
   the air to gaseous nitric acid and toxic organic nitrates.
Health Effects:
    can irritate the lungs and lower resistance to respiratory infection.


WATER QUALITY - is defined as the physical, chemical and biological characteristics of water.

Water pollutants which may be present in our Drinking Water:

a) Microorganisms
   – bacteria, viruses and parasites

     Health Effects:
      waterborne diseases caused by drinking water polluted with microorganisms include typhoid,
        ameobiasis, giardiasis, ascariasis and hookworm.

b)   Synthetic Organic Chemicals (SOCs)

c) Additives like Chlorine
   a. disinfection by-products – toxic chemicals formed by the combination of chlorine and
      organic chemicals in water (ex.: THM)

d) Inorganic Chemicals and Metals
   – toxic minerals like lead, mercury and arsenic

     Health Effects:
      conditions related to water polluted by chemicals include:
             Cancer, including prostrate cancer and non-Hodgkin’s lymphoma
             Hormonal problems that can disrupt reproductive and developmental processes
             Nervous system damage
             Liver and kidney damage
            Exposure to mercury may cause:
           (in the womb): neurological problems including slower reflexes, learning deficits, delayed
           or incomplete mental development, autism and brain damage.
           (in adults): Parkinson’s disease, multiple sclerosis, Alzheimer’s disease, heart disease and
           even death

 Waterborne diseases caused by polluted Recreational Water:
        Rashes, ear ache and pink eye
        Respiratory infections
        Hepatitis, encephalitis, gastro enteritis, diarrhea, vomiting and stomach aches


TOXICS AND WASTE

a) PCB (Polychlorinated Biphenyl)
-    used as coolants in insulating fluids for transformers and capacitors, plasticizers in paints and
    cement, stabilizing additives in flexible PVC coatings of electrical wiring and electronic
    components, lubricating and hydraulic oils, surgical implants, and in carbonless copy paper.

    Health Effects:
        causes chloracne and rashes
        causes cancer of the liver
        enhances breast carcinogenesis

b) DDT (Dichlorodiphenyltrichloroethane)
-  one of the most well-known synthetic pesticides..
-  moderately toxic
-  has been administered orally on rare occasions as treatment for barbiturate poisoning.

    Health Effects:
            causes cancer of the liver, pancreas, breast
            contributes to leukemia, lymphoma and testicular cancer

c) Dioxin
-   a class of super-toxic chemicals formed as by-product of the manufacture, molding and burning
   of organic chemicals and plastics that contain chlorine.
-   the most toxic man-made organic chemical

    Health Effects:
        causes cancer, spina bifida & other birth effects, autism, liver disease, endometriosis,
            reduced immunity, chronic fatigue syndrome, psychological disorders, and nerve & blood
            disorders.

d) PBDE (Polybrominated diphenyl ethers)
-  organobromine compounds that are used as flame retardants (BFRs).

    Health Effects:
        causes skin disorders, such as acne and hair loss

e) Hexachlorobenzene
-  a man-made chemical used as pesticide

    Health Effects:
        a probable human carcinogen
        causes liver, kidney, and thyroid cancers.

f) Mercury
-   one of the few substances known to have no natural function in the human body.
-   small amounts can act as a cumulative poison ,collecting over a long period of time until they
   reach dangerous levels.
    Health Effects:
        causes heavy metal chronic fatigue, dizziness, tendency to diabetes, high blood pressure,
            intestinal spasms, dry skin and metallic taste in mouth.

g) Lead
-  a soft, malleable, and corrosion resistant material
- a metal with no known biological benefits to humans.

    Health Effects:
         causes anemia and kidney damage & reproductive damage.
        
h) Asbestos
- a mineral fiber that has been used commonly in a variety of building construction materials for
    insulation and as fire retardant

    Health Effects

     Asbestosis - Asbestosis is a serious, progressive, long-term non-cancer disease of the
        lungs. It is caused by inhaling asbestos fibers that irritate lung tissues and cause the
        tissues to scar.

        Symptoms: Shortness of breath and a dry, crackling sound in the lungs while inhaling

     Lung Cancer - People who work in the mining, milling, manufacturing of asbestos,
        and those who use asbestos and its products are more likely to develop lung cancer
        than the general population.

        Symptoms: coughing and a change in breathing, shortness of breath, persistent chest
        pains, hoarseness, and anemia.

     Mesothelioma -- Mesothelioma is a rare form of cancer that is found in the thin
        lining (membrane) of the lung, chest, abdomen, and heart and almost all cases are
        linked to exposure to asbestos.



NOISE POLLUTION

Health effects:
 causes annoyance & aggression, hypertensions, high-stress levels, tinnitus, hearing loss and sleep
   disturbances
   FOOD SAFETY

   Types of Food Poisoning:
    Food Infection - refers to the presence of bacteria or other microbes which infect the body after
      consumption.
    Food Intoxication - refers to the ingestion of toxins contained within the food, including
      bacterially produced exotoxins, which can happen even when the microbe that produced the toxin
      is no longer present or able to cause infection.

   Key Principles of Food Hygiene (WHO)
    Prevent contaminating food with pathogens spreading from people, pets & pests.
    Separate raw and cooked foods to prevent contaminating the cooked.
    Cook foods for the appropriate length of time and at the appropriate temperature to kill the
      pathogens.
    Store food at proper temperature
    Use safe water and raw materials


   IONIZING RADIATION
   - consists of particles or electromagnetic waves that are energetic enough to detach electrons from
      atoms and molecules, thus ionizing them.
Examples:
    Ultraviolet radiation
      - may lead to direct DNA damage
      - treatment of skin conditions such as psoriasis and vitiligo
    Microwave radiation
       By: Ellen Gold B. Pinili




               Subject:

    Environmental Science


              Instructor:

Dr. Mary Evangeline F. Gajunera

				
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