The Environment and Human Health
Two types of Environment:
- encompasses all living and non-living things occurring naturally on Earth.
- 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.
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
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
contributes to the risk of developing cardiovascular and respiratory diseases, as well as of lung
c) Chlorofluorocarbon (CFC) - is an organic compound that contains carbon, chlorine and fluorine,
produced as a volatile derivative of methane and ethane.
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.
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.
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.
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:
– bacteria, viruses and parasites
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
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
Waterborne diseases caused by polluted Recreational Water:
Rashes, ear ache and pink eye
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.
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.
causes cancer of the liver, pancreas, breast
contributes to leukemia, lymphoma and testicular cancer
- 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
causes cancer, spina bifida & other birth effects, autism, liver disease, endometriosis,
reduced immunity, chronic fatigue syndrome, psychological disorders, and nerve & blood
d) PBDE (Polybrominated diphenyl ethers)
- organobromine compounds that are used as flame retardants (BFRs).
causes skin disorders, such as acne and hair loss
- a man-made chemical used as pesticide
a probable human carcinogen
causes liver, kidney, and thyroid cancers.
- 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.
causes heavy metal chronic fatigue, dizziness, tendency to diabetes, high blood pressure,
intestinal spasms, dry skin and metallic taste in mouth.
- a soft, malleable, and corrosion resistant material
- a metal with no known biological benefits to humans.
causes anemia and kidney damage & reproductive damage.
- a mineral fiber that has been used commonly in a variety of building construction materials for
insulation and as fire retardant
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.
causes annoyance & aggression, hypertensions, high-stress levels, tinnitus, hearing loss and sleep
Types of Food Poisoning:
Food Infection - refers to the presence of bacteria or other microbes which infect the body after
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
Store food at proper temperature
Use safe water and raw materials
- consists of particles or electromagnetic waves that are energetic enough to detach electrons from
atoms and molecules, thus ionizing them.
- may lead to direct DNA damage
- treatment of skin conditions such as psoriasis and vitiligo
By: Ellen Gold B. Pinili
Dr. Mary Evangeline F. Gajunera