air pollution v s s nair - nov 24
TRANSCRIPT
Air Pollution
V. S. S. Nair
Nov 24, 2010Institution of Engineers
DRINK 2 liters of water
BREATHE 15,000 liters of airMore than 10 liters every
minute!
In one day, we…
We can …
Live without food for more than 10 days
Survive without water for 3 days
NOT MORE THAN 3 MINUTES WITHOUT AIR
BUT…
AIR
Supplies the Oxygen necessary for all functions of the body including
brain
AIR
reaches 100 sq. meters of surface area of the lungs
Exercise & Breathing Exercise improves the body’s ability to deliver
oxygen It can increase the intake of air by as much as 10
times When we exercise in polluted air, we increase our
contact with pollutants; and increase our vulnerability to health damage
Air pollution is a key risk factor for a number of diseases andpoor general health
Air PollutionWho is at risk?
Children Elderly Prior heart or lung disease patients Diabetics Persons who work/exercise outdoors Otherwise healthy adults and children
Air PollutionHealth Problems
Impaired fertility Birth defects Respiratory infections Asthma Emphysema Lung Cancer Heart attacks Strokes Premature death
Air PollutionPyramid of effects
Lung function changes, immune cell responsesHeart rate or heart rate variability responses
Asthma attacks, medication use,symptoms
Doctor Visits
Hospital Admissions
Death
Air PollutionMain Pollutants
Ozone Particulates, especially PM 2.5 Air-borne toxics Mercury
Air Pollutants:Ground level Ozone
Ultra-violet light
Volatile Organics
Nitrogen oxides
Air Pollutants:Ground level Ozone
Nitrogen oxides
50% From Traffic
50% From Power plants
and Industry
Air Pollutants:Ground level Ozone
Seasonal variationDaily variation
OutdoorsDoes not penetrate buildings
Air Pollutants:Ground level Ozone
Caustic Gas – clear, colourless, odourless Oxidises proteins, lipids in the mucosal fluid
layer Highly irritating to lung linings Increases lung secretions, decreases
oxygenation Sets off airway bronchospasm Recruits inflammatory cells Increases responses to allergens Damages infection fighting responses Chronic lung damage/remodeling
Asthma Epidemic
50% in Children
100% in Adults
Ozone and Asthma attacks
Hundreds of published studies conducted
around the world all show the same results:
More Ozone Pollution exposure leads to more asthma attacks
Dose = Response relationship
Airway Obstruction
Ozone reduces Lung function
FEV
1,
% C
HA
NG
E
BASELINE 2HR 4HR-60
-40
-20
0
Ozone causes Asthma
Exercising children exposed to Ozone:A cohort study
Time Outdoors = Asthma
McConnell, et al. Lancet 2002: 359: 386-91
Ozone: Asthma effects
More people with Asthma More asthma attacks More asthma medicine usage More doctor, Casualty and Urgent Care
visits More children and elderly in hospitals More school absences More lost work days
Ozone: other effects
Allergy symptoms
Respiratory infections
Ear infections
Emphysema attacks
Overall death rates
Air pollutants: Particulates
SulfatesNitratesPolycyclic Aromatic Hydrocarbons
(PAH)Soot/ CarbonDust
Particulate Physiology
Penetrate deeply into lungs to alveoli
Irritate lung linings – more AsthmaStimulate immune system
inflammatory proteins
Air pollutants: Particulates
Year round exposures
Penetrate buildings
Particulates: Cardiac effects
Vascular inflammation
Blood clotting protein levels
Cardiac arrhythmias
Blood pressure
Heart rate variability
Alters Cardiac conduction
Particulates: Cardiac effects
Vascular inflammation is more important than cholesterol in the development of cardio-vascular disease
Air Pollution andNext-day Heart attacks
Short-term exposure to particulates (PM 2.5) increases the incidence of heart attacks for one day following exposure
As air pollution goes up, the risk of heart attack goes up
Increased particulate air pollution and the triggering of Myocardial infarctionPeters et al.; Circulation, June 12, 2001, vol. 103
Air Pollution andStroke deathsFine Particulate matter and
gaseous pollutants are significant risk factors for acute stroke death
Women and the elderly are most susceptible to the effects of particulate air pollutants
More air pollutionexposure
More acutestroke deaths=
Effect of Air Pollutants on Acute Stroke Mortality. Hong et al.Feb.,2002; Environmental health perspectives, v. 110. no.2
Effects on otherwise healthy people
Asthma rates in adults
Pneumonia & respiratory infections
Lung cancer rates similar to
living with a smoker
Overall death rates
Faster decline in lung function with age
Effects on children – A generation at risk
Multiple birth defects – heart, neural tube
Higher infant mortalityMore asthma Impaired lung developmentPremature emphysema Increased respiratory infectionsHigher health care expenditures
Final thoughts
Health and economic issue Prioritise air quality improvement in
decision-making Over half the problem is traffic Massive hidden health costs in
transportation and power pollution Imposed risk on all population groups,
especially our children and elderly