EESA10 midterm

Environment

is everything that affects a living organism

Factors of environment that effect human health

Air
Water
Soil
Biota
Manmade environment
(Created by society)

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

What is Environmental Health? (1)
According to the WHO:

“In its broadest sense, environmental health
comprises those aspects of human health,
disease and injuries that are determined or
influenced by factors in the environment.”

What is Environmental Health? (2)
According to the WHO:
“This includes the study of both the direct and the
indirect pathological effects of various:

❑ Chemical
❑ Biological
❑ Physical (only man-made)

Types of Hazards: Chemical Hazard

Chemicals in air, water, soil and food

Types of Hazards: Biological Hazard

Bacteria, viruses, parasites, allergens, animals such as bees and poisonous snakes

Types of Hazards: Physical Hazard (that are not environmental hazards)

Natural fires, tornados, hurricanes, volcanic eruptions, and earthquakes are not environmental health hazards (they are natural disasters or natural hazards)

Types of Hazards: Physical Hazard (that are environmental health hazards)

Housing, urban development, land use, transportation are environmental health hazards

Types of Hazards: Social or Behavioral Hazards and which are environmental health hazards

Poor diet, smoking, drugs, drinking, poverty are not environmental
health hazards (but the chemicals in a tobacco smoke are – second hand smoke)

Types of Hazards: Genetic Traits

Health risks associated with the chromosomal defect that causes
Down syndrome are not environmental health hazards

The Scope of Environmental Health

Core hazards:

Chemical

Biological

Physical

Hazards that influence core hazards:

genetic traits

social/behavioural

natural disasters

Boundaries are not sharp

Core concerns of Environmental Health, Focus on

chemical, biological, physical hazards

Core concerns of Environmental Health, Interactions with

genetic traits and with social/behavioral stressors

Core concerns of Environmental Health, Emphasis on

anthropogenic hazards

Core concerns of Environmental Health, Much more than just

pollution

Core concerns of Environmental Health, As branch of public health, the field of environmental health takes a

population perspective

Key Themes of this Course

• We make the world we live in and we live in the
world we make
• People living a modern Western lifestyle create,
use, and dispose of lots of “stuff”
• In an ecosystem, nothing ever goes away
• Therefore, our “stuff” and its byproducts are
transported and transformed, but they do not
disappear

• There has often been a lack of foresight in
adopting new products and technologies
• The natural environment is globally connected;
trade and travel are increasingly globalized
• Global disparities in development and health are
enormous
• Western-style development is not sustainable at
a global scale

Environmental Crisis: Human
Alteration of Earth
Atmosphere: CO2 increased ___ since ____

30% since the beginning of the
Industrial revolution

Environmental Crisis: Human
Alteration of Earth
Hydrosphere:

Geosphere:

Biosphere:

Industrialization:

Overpopulation and Overconsumption:

Hydrosphere: Polluted lake

Geosphere:1/3 to 1/2 of the land surface has
been transformed by human action

Biosphere: Deforestation

Industrialization: Release of chemicals into atomsphere

Overpopulation and Overconsumption: strains resources and leads to environmental degradation, the excessive use of resources beyond what is needed or sustainable, exacerbates the problem by depleting resources and contributing to pollution

____________ is the clearest
indicator of environmental threats to human health

The declining health of other organisms

Decline in number of
frogs (no single
factor is responsible)

Increase UV
Traces of toxic
chemicals
Infections (fungi and
bacteria)
Predators

Environmental Health
Environmental factors are responsible for

25 % of all
preventable diseases

In developing countries ______ infections
are heading the list

In developing countries diarrhea and respiratory infections
are heading the list

Protecting the environment has been a

mainstream of public health practices since 1878

general populations for studying environmental health

rich & poor, African Americans & Hispanic & Whites, Developed & developing countries

New york city study:

African American, Hispanic and low income populations
have been found to have hospitalization and death rate from asthma 3-5 times higher than those for all New York City residence

Chemicals in new york study:

Pollutant, African Americans, Hispanic, Whites
Particulates 16.5 34.0 14.7
Carbon monoxide 46.0 57.1 33.6
Ozone 62.2 71.2 52.5
Sulfur dioxide 12.1 5.7 7.0
Lead 9.2 18.5 6.0

Two case studies on outdoor air pollution:

London smog, Indonesian fires

London case study:

The Great Smog of London in 1952 was a severe air pollution event that impacted the city for five days, from December 5th to 9th. It was caused by a combination of industrial emissions and specific weather conditions that trapped pollutants near ground level. The smog was so dense that it brought the city to a standstill and resulted in thousands of deaths, primarily due to respiratory illnesses, due to sulfure dioxide and smoke

Cause:

The smog was a result of a combination of factors. London's heavy reliance on coal for heating and industrial activities, coupled with a high-pressure weather system that created a temperature inversion (warm air trapping cooler, polluted air near the ground), led to a buildup of pollutants. 

• Impact:

  The smog was incredibly dense, reducing visibility to near zero in many areas. Pedestrians and vehicles struggled to navigate the city, and public transportation was severely disrupted. The event resulted in an estimated 12,000 excess deaths, primarily due to respiratory problems. 

• Consequences:

  The Great Smog led to the passage of the Clean Air Act in 1956, which aimed to reduce air pollution by regulating the use of coal and promoting cleaner energy sources. The event is also considered a turning point in public awareness and government action regarding air pollution

Indonesian fires

Use of fires to clear land for agriculture, due to severe drought of El Nino, resulted in an unprecedented fire episode where more than 9 million hectares of land were burnt in Indonesia. Smoke from the fires hung as a huge blanket over Southeast Asia, covering large cities such as Kuala Lumpur and Singapore, restricting traffic (air, sea and land) and causing a severe health hazard.

Sources of Outdoor Air Pollution types of pollutant sources

Human sources: stationary → factory

Human sources: mobile → transportation

Natural sources: Weather, geological events → Volcanoe erruption

Primary outdoor air pollutants

CO, CO2, SO2, NO, NO2, hydrocarbons, particulates

Secondary outdoor air pollutants

HNO2, HNO3, SO3, H2SO4, H2O2, O3, PANs, most NO3 and SO4 2- salts

Key major sources of major air pollutants from burining fossil fuels

Vehicles gasoline/diesel, Electrical power plants coal or oil, Heating for buildings oil or natural gas, Manufacturing coal oil or natural gas

All burning of fossil fuels produces

CO2, PM

Health Effects of Outdoor Air Pollution

The effects depend on the dose or concentration:

Asthma, Chronic bronchitis, Pulmonary emphysema

Health Effects of Outdoor Air Pollution, Caused or exacerbated by exposure to air pollution

–Lung Cancer
–Heart disease
–Toxic poisoning
–Eye irritation
–Birth defects

Asthma caused by

Particulates and/or SO2 can irritate bronchial passages leading to severe difficulties in breathing

Chronic bronchitis caused by

• 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

Pulmonary emphysema caused by

• 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

Seven common outdoor air pollutants ;

___- air pollutants:

____- air pollutant

• Primary air pollutants
– Particulate matter
– Carbon monoxide
– Nitrogen oxides
– Sulphur oxides
– VOC (Volatile Organic
Compounds)
– Lead
• Secondary air pollutant
– Ground level Ozone

Particulate Matter is:

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

• Particulates classified by size

• PM10 —respirable
• PM2.5 —“fine” (mostly from combustion)
• Ultrafine particulates

Source of each type of PM:

Natural and mechanical sources → 2.5 to 10 microns

Combustion → 0.1 to < 2.5 microns

diesel combustion → < 0.1 microns

How each PM effects body:

respirable: settle in trachea and bronchi → removed via coughing

fine: reach small airways and aveoli → removed from aveoli

ultrafine: can pass into bloodstream

CO what it is and how it forms:

• Odourless, colourless gas
• Incomplete burning of carbon containing
fuels
• Heaters, woodstoves, gas stoves, fireplaces,
water heaters, automobile exhaust, and
tobacco smoke

• Fetuses, infants, elderly and people with heart
and respiratory illnesses are at high risk for
adverse health effects

What is confused for food poisoning or flu

carbon monoxide poisoning

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, Death

CO prevention

• 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), what is and how it forms

• Formed in any type of combustion process
• Involved in formation of ground level ozone
• Forms nitrate particles, and acid aerosols

what outdoor air pollutant forms acid rain and transports over long distances

Nitrate oxides

Sulphur Oxides (SOx), how it forms and how it is contaminant

• 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

Sulphur Oxides (SOx)

VOC (Volatile Organic Compounds), what it is and why contaminant

• Variety of organic compounds used as solvent
in industry, automobiles
• Hydrocarbons (HC): methane, butane,
propane
• Some produce photochemical smog

Lead (Pb) (outdoor air pollutant), what it is and why it is contaminant

• Metal
• Vehicles and industrial sources
• Leaded gasoline
• Deposit on soil and water
• Children accidentally can eat soil
• Particularly affects young children

(outdoor air pollutant) Lead is ____, effects are :

• 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) equation:

VOC + NOx + Heat + Sunlight = Ozone

O3 formations

• Summertime pollutant, time of the day, seasonal, climate
• Good in stratosphere
• Bad on a ground
• Transported on long distances

O3 effects

• 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 pick

What is smog, types of smog

• Smoke + fog = Smog (first used in 1905 in
England)
• Sulphurous smog- London type of smog or
industrial smog
• Photochemical smog - L.A. type of smog or
brown air

formation of photochemical smog

transportation creates NO, factories and gas stations create carbon dioxide and hydrocarbons. Reactions occur in atmosphere with compounds. Brown smog is formation of Nitric acid, PANs, formaldehyde and other aldehydes and Ozone with solar energy.

indoor air pollution vs outdoor

• Contains 2-5 times higher concentration of hazardous
pollutants than outdoor air

Sick building syndrome definition

– 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

Sick Buildings Syndrome most likely cause is ____ with __ %

Inadequate venting with 53 %

Probable causes of sick building syndrome

Inside source, outside source, microbiological, building material, inadequate venting, unknown

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 how it contaminates

• 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

What abestos is used in

• 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 might you 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 in body

- Affect the lungs and the membrane that surrounds the lungs

-Abestosis

- Plaques in the pleural membranes
- Lung cancer, mesothelioma
- Increase risk of getting other types of cancer
(stomach, esophagus, pancreas, kidney)
- Risk increases with smoking

Asbestosis

• Asbestosis- Scar-like tissue, not in
general public
– difficulty breathing,
– often cough,
– heart enlargement
– lead to disability and death

Formaldehyde, what it is and how it forms

• Volatile organic
compound (VOC),
naturally occurring gas,
colourless, and strong
smell
• Becomes a gas at normal
room temperature
• Also released by burning
wood and natural gas, by
automobile and by
cigarettes

Where formaldehyde is used (indoor air pollution)

• Glue or adhesives in pressed
  wood 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 how it forms and where it forms

• 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

Mold and Moisture, how to identify and remove

• 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 contains ___ compounds, __ are carcinogens

Contain 4 000 compounds (CO and Formaldehyde), 40 are carcinogens

A non-smoker exposed to secondhand smoke
has a ___ increased chance of developing lung
cancer

25%

Health Canada estimates that more than ___
non-smokers die from lung cancer each year
because of such exposure

300

• Environmental tobacco smoke (secondhand smoke) effects on adults and children and why concern:

– Adults: heart disease, heart attack, lung cancer,
hearing loss, eyes, nose and throat irritation
– Children: SIDS, asthma, pneumonia, bronchitis,
ear infection and hearing loss

• Smoking is on the rise in less developed
countries

Third hand smoke

smoke that gets on clothing and furniture

Radon Gas, what it is and how it occurs

● 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, how it occurs and why hazard

– Begins series of rapid breakdowns
– Radon and some progeny are alpha emitters;
lung cancer risk
– Often simple to detect and
remediate

Air Dust, how it occurs and why concern

• Heating and cooling -forced air system
• Dust particles
• Pollen or other debris
• Duct Cleaning Service Providers

cause exposures to :

Dust Mites, Pollen, Mold, Pet Dander, Bacteria / Viruses

Why earth is called Liquid Natural Capital:

• The Earth is a water planet
• Water covers 71% of the Earth’s surface
• Mostly salty water
• No species can live without water
• Sculpting the Earth’s surface
• Moderating climate
• Removing and diluting wastes and pollutants

major environmental concerns of water

Quantity of water, Quality of water

__ % is readily available fresh water

0.014%

most water is in the world at __ %

ocean and saline water at 97.4%

____ % is fresh water in the world with _ % is ice caps

2.6 % with 1.984 % ice caps

Water stress

<1700 cubic meters/year/person

Water scarcity

<1000 cubic meters/year/person

Some areas have lots of water but

the largest rivers are far from agricultural and population centers

Lots of precipitation arrives during a short period but

cannot be collected and stored