human health and environment review

what is the environment?

Environment is everything that affects a living organism

Effects of environment on human health is so great

Air

Water

Soil

Biota

Manmade environment

(Created by society

your environment is your health but….

its not the only factor influencing your health

gene-environment interaction

Genetic makeup and environmental factor are

independent risk factors

• Models of gene-environment interaction

– Genetic makeup increases exposure to an

environmental risk factor

– Genetic makeup increases susceptibility to an

environmental risk factor

types of hazards

chemical hazard

biological hazard

physical hazard

social or behavioral hazards

genetic traits

core concerns of environmental health

Focus on chemical, biological, physical hazards

Interactions with genetic traits and with

social/behavioral stressors

Emphasis on anthropogenic hazards

Much more than just pollution

As branch of public health, the field of

environmental health takes a population

perspective

atmosphere

CO2 increased 30% since the beginning of the

Industrial revolution

hydrosphere

polluted lake

geosphere

1/3 to ½ of the land surface has been transformed by human action

environmental health

Environmental factors are responsible for 25 % of all

preventable diseases

In developing countries diarrhea and respiratory infections

are heading the list

Protecting the environment has been a mainstream of

public health practices since 1878

Rich & Poor

African Americans & Hispanic & Whites

Developed & developing countries

airborne hazards

outdoor air pollution and indoor air pollution

health effects of outdoor air pollution

The effects depend on the dose or concentration

Asthma

• Particulates and/or SO2 can irritate bronchial passages leading to severe

difficulties in breathing

• Prevalence in the US increased 34%

• The incidence among a children in Australia was one in five, a doubling of

the rate in less than 20 years

• Indoor air pollution is also significant cause

Chronic bronchitis

• Occurs when an excessive amount of mucus is produced in bronchi which

results in a lasting cough

• SO2 and smoking is related to Chronic bronchitis

some health effects of outdoor air pollution

Pulmonary emphysema

• Weakening of the wall of alveoli, they become enlarged and

loss their resilience

• Shortness of breath is the primary symptom

• NO2 is related to emphysema

–Lung Cancer

–Heart disease

–Toxic poisoning

–Eye irritation

–Birth defects

seven common outdoor air pollutants

Primary air pollutants

– Particulate matter

– Carbon monoxide

– Nitrogen oxides

– Sulphur oxides

– VOC (Volatile Organic

Compounds)

– Lead

• Secondary air pollutant

– Ground level Ozone

Particulate Matter

Particles found in the air (dust, soot, smoke, and liquid droplets)

• Vehicles, factories, construction sites, tilled fields, stone

crashing, and all kinds of burning

• Some formed in the air

• Serious health effects

• Big and small

Particulates classified by size

• PM10 —respirable

• PM2.5 —“fine” (mostly from combustion)

• Ultrafine particulates

Carbon Monoxide

Odourless, colourless gas

• Incomplete burning of carbon containing

fuels

• Heaters, woodstoves, gas stoves, fireplaces,

water heaters, automobile exhaust, and

tobacco smoke

• Bigger problem for indoor air pollution

1 000 people die each year in US as result of

CO poisoning (indoor air)

• Sometimes confused with flu or food

poisoning

• Fetuses, infants, elderly and people with heart

and respiratory illnesses are at high risk for

adverse health effects

health effects of carbon monoxide

Interferes with the delivery of

oxygen in the blood to the rest of

the body

• Worsen cardiovascular conditions

• Fatigue

• Headache

• Weakness

• Confusion

• Disorientation, loss of coordination

• Nausea, Dizziness, Deat

prevention meaning

Never leave a car engine running in a shed or

garage or in any enclosed space

• Proper selection, installation, and

maintenance of appliances

• Correct use of appliances

• Good ventilation

• Use CO detectors

Nitrogen Oxides (NOx)

Formed in any type of combustion process

• Involved in formation of ground level ozone

• Forms nitrate particles, and acid aerosols

• Contribute to formation of acid rain

• Transported over long distances

Sulphur Oxides (SOx)

Burning of coal and oil, extraction of metals from ore

• SO2 dissolve in water vapour to form acids

• Acids react with other gases and particles and form

sulphates

• Transported over long distances

• Respiratory illnesses, aggravates existing heart and

lung diseases

VOC (Volatile Organic Compounds)

Variety of organic compounds used as solvent

in industry, automobiles

• Hydrocarbons (HC): methane, butane,

propane

• Some produce photochemical smog (will be

explained later)

Lead (Pb)

Metal

• Vehicles and industrial sources

• Leaded gasoline

• Deposit on soil and water

• Children accidentally can eat soil

• Particularly affects young children

Lead is neurotoxicant

– Effects on

• IQ, cognitive & neurological performance more

broadly

• Cardiovascular mortality, increased lung cancer

risk, kidney toxicity, high blood pressure,

reproductive effects, and oral health impacts

– Heavier burden of exposure on poor,

nonwhite populations

Ozone (O3)

• Summertime pollutant, time of the day, seasonal, climate

• Good in stratosphere

• Bad on a ground

• Transported on long distances

• Lung damage (small airways)

• Shortness of breath, chest tightness, coughing and nausea

• Irritate and damaged eyes, nose, sinuses and throat

• Problem for people who exercise outdoors during the

concentration picks

smog

• Summertime pollutant, time of the day, seasonal, climate

• Good in stratosphere

• Bad on a ground

• Transported on long distances

• Lung damage (small airways)

• Shortness of breath, chest tightness, coughing and nausea

• Irritate and damaged eyes, nose, sinuses and throat

• Problem for people who exercise outdoors during the

concentration picks

airborne hazards

outdoor air pollution

indoor air pollution

indoor air pollution

Contains 2-5 times higher concentration of hazardous

pollutants than outdoor air

• Buildings more airtight to conserve energy, inadequate

ventilation

• People spend about 90% of their time indoors

• Children, pregnant women, elderly, and people with

chronic illnesses are more sensitive

sources of pollutants

Building materials and furnishing

• Asbestos insulation

• Wet or damp carpet

• Furniture made of certain pressed wood products

• Cleaning products and air fresheners

• Personal care and hobbies

Pesticides

• Cooking

• Bathing

• Heating (combustion of

oil, coal, wood)

• Radon

• Smoking

• Outdoor pollution

unhealthy construction materials and sick buildings

Sick building syndrome”

– Nonspecific symptoms experienced by occupants

of a building

• “Sick building” designation

– A building whose occupants experience such

symptoms

• Building-related illness

– Specific diagnosable illness, linked to specific

feature of building

health effects of indoor air pollution

Hard to detect by our

senses

• Symptoms are similar,

need years to develop

• Headaches, tiredness,

dizziness, nausea, itchy

nose, scratchy throat

• Asthma

• Cancer

six common indoor air pollutants

Asbestos

• Formaldehyde

• Mold and Moisture

• Secondhand Smoke

• Radon Gas

• Air Dust

asbestos

Group of six different

fibrous minerals

• Have separable, long,

strong and flexible

heating resistant fibers

asbestos in the environment

Do not evaporate into air or dissolve in water,

do not break down

• Fibers and particles may remain suspended in

the air and carried long distances

• Not able to move through soil

asbestos used in

Building materials (roofing

shingles, ceilings and floor tiles,

paper products, and asbestos

cement products)

– Friction products (automobile

brakes and transmission parts)

– Heat resistant fabrics,

packaging and coatings

how could people be exposed to asbestos?

In industrialized countries, nearly everyone has

asbestos fibers in their lungs

– Some risk of cancer

• People working in some industries

• People living near these industries

• During demolition work and remodeling

• From drinking water

(natural sources or asbestos

containing cement pipes)

health effects of asbestos

Affect the lungs and the membrane

that surrounds the lungs

• Asbestosis- Scar-like tissue, not in

general public

– difficulty breathing,

– often cough,

– heart enlargement

– lead to disability and death

health effects of asbestos

Plaques in the pleural membranes

● Thickened areas of tissue on the lung lining

● Lung cancer, mesothelioma

● Increase risk of getting other types of cancer

(stomach, esophagus, pancreas, kidney)

● Risk increases with smoking

● Not related with birth defects

● Low levels can be measured in urine,

faces, and mucus

formaldehyde is?

Volatile organic compound (VOC), naturally occurring gas, colourless, and strong

smell

• Becomes a gas at normalnroom temperature

• Also released by burning wood and natural gas, by automobile and by cigarettes

Glue or adhesives in pressedwood products (particleboards,MDF, plywood)

• Preservatives in some paints and cosmetics

• Coatings that provide permanent press quality to fabrics and draperies

• Finish used to coat paper products

• Certain insulation materials

health effects of formaldehyde

Allergic reactions

– Watery eyes, burning sensation in the eyes, nose and throat

– Skin rashes

• Nausea

• Coughing

• Chest tightness

• Asthmatic reactions

• Cancer

• Some people very sensitive

mold and moisture

Need moisture, does not need standing water, just requires high relative air humidity

– Bathrooms and

kitchens

– Gym areas

– Locker rooms

– Leaky roof areas

– Damp basements

– On or within wood,

paper, carpet and

foods

mold health effects

Major source of indoor allergens

• Trigger asthma

• Produce Toxins

• Produce Irritants

The way to control indoor mold growth is to

control moisture (maintaining the relative

humidity between 30-60%)

• Often undiscovered

• Produce tiny spores

• Discoloration and odour problems

second hand smoke

Contain 4 000 compounds (CO and

Formaldehyde), 40 are carcinogens

● A non-smoker exposed to secondhand smoke

has a 25% increased chance of developing lung

cancer compared with not exposed non-smoker

● EPA estimates that each year 3 000 lung cancer

deaths among nonsmoking adults in US

● Health Canada estimates that more than 300

non-smokers die from lung cancer each year

because of such exposure

environmental tobacco smoke

Adults: heart disease, heart attack, lung cancer, hearing loss, eyes,

nose and throat irritation

– Children: SIDS, asthma, pneumonia, bronchitis, ear infection and

hearing loss

• Prevalence is generally falling in most countries worldwide,

including many low- and middle-income countries (where

80% of the world's smokers live)

• Rates are stable or decreasing, while the absolute number of

smokers is not declining, and some countries still report rising

numbers.

– More than 8 million people projected to die from smoking-

related causes by 2030

radon gas

Colorless, odorless, tasteless

● Naturally occurring

● Radioactive decay of uranium

● From soil and rock into

basements and lower floors

indoor air

● Dissolved in groundwater,

pumped into wells and then

into homes

● In construction building

blocks

radon gas in buildings

Natural hazards in some regions

– Begins series of rapid breakdowns

– Radon and some progeny are alpha emitters;

lung cancer risk

– Often simple to detect and

remediate

air dust

Heating and cooling -forced air system

• Dust particles

• Pollen or other debris

• Duct Cleaning Service Providers