Overview of air pollution: Overview of air pollution A/Prof Bin Jalaludin MBBS, MPH, PhD, MRCP (UK), FAFPHM South Western Sydney Area Health Service, and University of New South Wales


This talk: This talk Will give an overview of air pollution Will mainly focus on the common outdoor air pollutants Will discuss types of air pollutants Will discuss sources of air pollutants Will discuss health effects of air pollution


Air pollution – the problem : Air pollution – the problem Global Ozone layer depletion Greenhouse effect Regional Acid rain Haze and photochemical smog Local Indoor (homes, factories, offices)


Air pollution – the problem: Air pollution – the problem


Slide5: Effects of human activities on the atmosphere (NSW SOE 2000)


Ozone Layer Depletion: Ozone Layer Depletion Stratospheric ozone reduces harmful UV radiation Chloroflurocarbons (CFCs), methyl chloroform, carbon tetrachloride, halons, methyl bromide Montreal Protocol on Substances that Deplete the Ozone Layer


The vertical distribution of ozone in the atmosphere at mid-latitudes (Commonwealth SOE 2001): The vertical distribution of ozone in the atmosphere at mid-latitudes (Commonwealth SOE 2001) Source: after WMO (1999)


Postulated steps from the release of halocarbons to increase in UV related biological damage: Postulated steps from the release of halocarbons to increase in UV related biological damage Halocarbons release chlorine and bromine ‘radicals’ Increase in ultraviolet-related biological damage Stratospheric ozone layer depleted Chlorine and bromine ‘radicals’ destroy ozone molecules Increase in ultraviolet irradiance at ground level 1 2 3 4 Source: McMichael 1993


Slide9: Average stratospheric ozone concentrations for the month of October (NSW SOE 2000) Source: Bureau of Meteorology data, as at 1999


Slide10: Concentrations of ozone-depleting substances, Cape Grim, Tasmania (NSW SOE 2000) Source: CSIRO data, as at 1999


Past and future stratospheric chlorine levels (ppb, cumulative) of the major ozone-depleting substances (Commonwealth SOE 2001): Past and future stratospheric chlorine levels (ppb, cumulative) of the major ozone-depleting substances (Commonwealth SOE 2001) Source: Madronich and Velders (1999).


Greenhouse Gases: Greenhouse Gases Naturally occurring gases - CO, methane Anthropogenic gases – CO2, nitrous oxide, chlorofluorocarbons (CFCs)


Slide13: Source: CSIRO Atmospheric Research.


Slide14: Source: Bureau of Meteorology


Slide15: Global warming potentials of greenhouse gases Potentials are expressed as a multiple of the global warming potential of carbon dioxide. (Commonwealth SOE 2001)


Slide16: Carbon dioxide concentrations, Cape Grim, Tasmania (NSW SOE 2000) Source: CSIRO data, as at 2000


Slide17: Methane concentrations, Cape Grim, Tasmania (NSW SOE 2000) Source: CSIRO data, as at 2000


Slide18: Nitrous oxide concentrations, Cape Grim, Tasmania (NSW SOE 2000) Source: CSIRO data, as at 2000


Acid Rain: Acid Rain Emissions of oxides of sulphur and nitrogen produce Acid Aerosols - H2SO4, HNO3 (also regional pollutant) Coal fired (and oil fired) power plants Trans-boundary issue (especially in Europe and North America)


Health Effects of Global Environmental Changes: Health Effects of Global Environmental Changes


Possible adverse effects upon human health caused by global environmental changes: Possible adverse effects upon human health caused by global environmental changes A The designations ‘early’ and ‘late’ are notional, and indicate relative timing. (Based on McMichael, 1993.3)


Possible adverse effects upon human health caused by global environmental changes (cont.): Possible adverse effects upon human health caused by global environmental changes (cont.) A The designations ‘early’ and ‘late’ are notional, and indicate relative timing. (Based on McMichael, 1993.3)


Regional/Local Air Pollutants: Regional/Local Air Pollutants Criteria (Common) Air Pollutants - (ambient air quality standards established) Regional Photochemical smog - Ozone (O3) Haze - Particulates (PM) & Nitrogen Dioxide (NO2) Local Sulphur Dioxide (SO2) Carbon Monoxide (CO) Lead (Pb) Air Toxics - (often no standards)


Air toxics or Hazardous Air Pollutants (HAPS) – a definition: Air toxics or Hazardous Air Pollutants (HAPS) – a definition “gaseous, aerosol or particulate pollutants (other than the six criteria pollutants) that are present in the air in low concentrations with characteristics such as toxicity or persistence so as to be a hazard to human, plant or animal life”


Air Toxics / HAPS: Air Toxics / HAPS Diverse range of toxic compounds Volatile Organic Compounds (VOCs) formaldehyde: lung, eye, skin irritants benzene, 1,3-butadiene: carcinogens Persistent organic pollutants (POPs) DDT, PCB, dioxins: toxic, persistent, bioaccumulate Polycyclic Aromatic Hydrocarbons (PAHs) Benzo[a]pyrene: Incomplete combustion of organic matter – lung cancer, immune system suppression, respiratory problems Toxic Metals (associated with PM or as gases) Arsenic, cadmium, lead, mercury, nickel, chromium: persistent, bioaccumulate, toxic - kidney/liver damage, CNS disorders


Air Toxics / HAPs: Air Toxics / HAPs Diverse range of point and diffuse sources point sources: industries and other facilities emitting in a localised area diffuse sources: mobile sources (eg: road vehicles, boats), area based sources (eg: wood burning, dry cleaning, paints, thinners) Indoor / in vehicle exposures Increasing regulatory / public concern Generally little or no exposure data US EPA - list of 189 HAPs (1990)


Slide28: List of priority hazardous air pollutants (Commonwealth SOE 2001)


NEPMS (standards) to be developed for 5 air toxics in Australia: NEPMS (standards) to be developed for 5 air toxics in Australia benzene formaldehyde polycyclic aromatic hydrocarbons toluene xylenes


Criteria for selection for inclusion:: Criteria for selection for inclusion: Excluded air toxics from point sources Adequate ambient monitoring data exists Significant risk to human health Has highest mass emissions to the environment


Review of air toxics and health studies in Australia: Review of air toxics and health studies in Australia WA Department of Environmental Protection: Found 10 studies 9 studies addressed air toxics and health 1 study measured personal exposure 1 study in the ambient setting, 9 in occupational/indoor settings Formaldehyde was the most researched air toxic Source: State of knowledge report: Air toxics and indoor air quality in Australia. (EA, 2001)


Indoor air pollution: Indoor air pollution Indoor air can be defined as any non-industrial indoor space where a person spends a period of an hour or more in any day. This can include the air space in the office, classroom, motor vehicle, shopping centre, hospital and home.


Indoor air pollution: Indoor air pollution The quality of indoor air is influenced by two major factors: amount and quality of outdoor air getting in (ventilation rates, deposition and chemical decay) indoor sources of emissions of air pollutants


Indoor air pollution: Indoor air pollution In winter 80 - 90% of time indoors - mostly in own home A number of important indoor air pollutants Particles Environmental tobacco smoke (ETS) Oxides of nitrogen Formaldehyde Biological pollutants – house dust mites, moulds, etc


Particles in homes - no major sources: Particles in homes - no major sources Source: V Sheppeard, NSW Health


Fine particle (PM10) levels by number of smokers in house: Fine particle (PM10) levels by number of smokers in house Source: V Sheppeard, NSW Health


Fine particle (PM10) levels by main heating type: Fine particle (PM10) levels by main heating type Source: V Sheppeard, NSW Health


Slide39: Average levels of total suspended particles in selected Sydney clubs & hotels (NSW SOE 2001) Source: Cummins et al. 1990


Average weekly nitrogen dioxide levels in homes: Average weekly nitrogen dioxide levels in homes Source: V Sheppeard, NSW Health


Slide41: Peak 1-hour average concentrations of nitrogen dioxide, indoors & outdoors, 1987-97 (NSW SOE 2000) Source: Ferrari 1997


In car carbon monoxide levels: In car carbon monoxide levels Source: CARB 1998; V Sheppeard, NSW Health


Other in-car exposures (VIC EPA - mean personal concentrations while commuting to CBD (east route) - pilot trial): Other in-car exposures (VIC EPA - mean personal concentrations while commuting to CBD (east route) - pilot trial) Source: V Sheppeard, NSW Health


Air toxics in other microenvironments: Air toxics in other microenvironments Source: WA DEP; V Sheppeard, NSW Health


Burden of disease attributable to indoor smoke from solid fuels(% DALYs in each subregion)(The World Health Report 2002): Burden of disease attributable to indoor smoke from solid fuels (% DALYs in each subregion) (The World Health Report 2002)


Ambient air pollution: Ambient air pollution


A historical perspective of air pollution: A historical perspective of air pollution In 1273, England’s King Edward I passed a law prohibiting the use of at least one type of coal In the early 1400's, Henry V formed a commission to oversee the use of coal in the city of London In 1661, Charles II ordered the scientist John Evelyn to survey the effects of the increasing air pollution over the city. Evelyn recognised the relationship between the ‘dismal cloud’ over London and a number of fatal diseases but his warnings of the need for control were ignored


A historical perspective of air pollution (cont): A historical perspective of air pollution (cont) By the late 1800's industrialisation accompanied by the migration of people into cities increased the quantity and diversity of chemical pollutants entering the air In December 1873 weather conditions producing stagnant air and a temperature inversion  thick cloud of pollutants covering London for several days  about 1,150 deaths, making it one of the earliest air pollution disasters


A historical perspective of air pollution (cont): A historical perspective of air pollution (cont) Since 1873 at least 40 episodes of sudden buildups of air pollution have caused widespread casualties in the industrialised world


A historical perspective of air pollution (cont): A historical perspective of air pollution (cont) Several air pollution episodes occurred in London, England from December 1952 to 1962, with the most famous air pollution episode in December 1952 being responsible for an estimated 4,000 deaths.


London smog and deaths (1): London smog and deaths (1)


London smog and deaths (2): London smog and deaths (2)


Early Control Measures: Early Control Measures Government regulation UK Clean Air Act (1956) US Clean Air Act (1963, 1970 amendement) Standards for 6 air pollutants (called criteria pollutants) Reviewed every 5 years Cost-benefit analysis Victorian Clean Air Act (1958), NSW Clean Air Act (1961) Standards to establish “safe” thresholds Control strategies to reduce/prevent exceedences


Air Quality Standards: Air Quality Standards USA 1970 amendment to the 1963 Clean Air Act National Ambient Air Quality Standards (NAAQS) UK Expert Panel on Air Quality Standards established in 1991 Australia National standards in 1998


Slide58: Schedule 2 of the NEPM giving National Environment Protection Standards for ambient air quality (Commonwealth SOE 2001)


Primary / secondary pollutants: Primary / secondary pollutants Primary pollutants Particles NOx SO2 CO Secondary pollutant Ozone Particles (gaseous pollutants forming aerosols)


Types of air pollution: Types of air pollution Summer episodes (photochemical episodes) Secondary pollutants – O3, H2SO4, HNO3 Ozone is the index pollutant “White haze” Winter episodes Particles, SO2 “Brown haze”


Air pollution concentration: Air pollution concentration Complex interactions of many influences: quantities of pollutants emitted, the spatial and temporal distributions of these emissions rates of pollutant transport, dispersion and diffusion in the atmosphere meteorological conditions such as temperature and sunlight intensity atmospheric chemical reactions topography of the region


The role of the atmosphere in the air pollution source sink relationship: DISPERSION Vertical and horizontal – stability, turbulence, wind TRANSFORMATION Chemical reactions REMOVAL Settling, scavenging adsorption, impaction EMISSIONS Rate, type, source configuration RECEPTOR RESPONSE Health effects, vegetation damage, soiling, corrosion The role of the atmosphere in the air pollution source sink relationship


Sources of air pollution: Sources of air pollution Mobile sources Motor vehicles, rail, shipping, aviation Industry sources Power stations, petroleum refining, chemical manufacturing Area based sources – small point sources Service stations, combustion sources, lawn mowing


Slide64: Sources of 1995 to 1996 emissions for Port Phillip Region, Vic. (Commonwealth SOE 2001)


Slide65: Source: Commonwealth SOE 2001


Sources of emissions and exposure to benzene in the USA. (Commonwealth SOE 2001): Sources of emissions and exposure to benzene in the USA. (Commonwealth SOE 2001) Source: Data from Ott and Roberts (1998).


Anthropogenic emission sources – Sydney and Greater MAQS region: Anthropogenic emission sources – Sydney and Greater MAQS region


Pollutant emissions & VKT of vehicle fleet, Sydney: Pollutant emissions & VKT of vehicle fleet, Sydney


Slide69: Source: Carnovale et al. 1997 Contribution of wood burning to TSP, Sydney (NSW SOE 2000)


Why is air pollution an issue?: Why is air pollution an issue? Affects large numbers of people Involuntary exposure The health costs are enormous Also affects the health of flora and fauna Other health benefits from air pollution control – road trauma, physical activity


Burden of disease attributable to urban air pollution(% DALYs in each subregion)(The World Health Report 2002): Burden of disease attributable to urban air pollution (% DALYs in each subregion) (The World Health Report 2002)


Total Annual Economic Costs of Motor Traffic Air Pollution (AUD$m) (Bureau of Transport and Regional Economics 2003): Total Annual Economic Costs of Motor Traffic Air Pollution (AUD$m) (Bureau of Transport and Regional Economics 2003)


Adverse health effects estimated to be avoided by meeting the US EPA’s 80 ppb 8-h average daily maximum standard in New York City, NY. (Thurston 1997): Adverse health effects estimated to be avoided by meeting the US EPA’s 80 ppb 8-h average daily maximum standard in New York City, NY. (Thurston 1997) 2,000,000 Acute Respiratory Symptom Days/yr (i.e., person-days during which respiratory symptoms such as chest discomfort, coughing, wheezing, doctor diagnosed flu, etc. are experienced) 930,000 Restricted Activity Days/yr (i.e., person-days on which activities are restricted due to illness 180,000 Asthma Attacks/yr (i.e., person-days during which notably increased asthma symptoms, e.g., requiring extra medication, are experienced) 3,500 Respiratory ED Visits/yr 265 240 75 Non-asthma Respiratory Hospital Admissions/yr Deaths/yr Asthma Hospital Admissions/yr (0.01% of all adverse impact cases)


Environmental & human health effects of major air pollutants (NSW SOE 2000): Environmental & human health effects of major air pollutants (NSW SOE 2000) Source: NHMRC 1996; EPA 1997a


Environmental & human health effects of major air pollutants (cont.): Environmental & human health effects of major air pollutants (cont.) Source: NHMRC 1996; EPA 1997a


Slide81: Source: EPA 1993 (data from ANSTO) Size & distribution of particles in the atmosphere (NSW SOE 2000)


PM10 – Health effects: PM10 – Health effects Acute effects Decreased lung function Increased respiratory symptoms Hospitalisation/other health care visit Mortality Increased plasma viscosity,heart rate variability Chronic effects Increased mortality rates, reduced survival times, chronic cardiopulmonary disease, reduced lung function


Stylized summary of acute exposure studies, percent change in health end-point per 10 g/m3 change in PM10: Stylized summary of acute exposure studies, percent change in health end-point per 10 g/m3 change in PM10


Estimated percent changes in daily mortality associated with a 10 g/m3 increase in PM10 (with 95% confidence intervals) for a number of cities: Estimated percent changes in daily mortality associated with a 10 g/m3 increase in PM10 (with 95% confidence intervals) for a number of cities


Ozone - Acute Health Effects: Ozone - Acute Health Effects Decreases in lung function Increase in respiratory symptoms, asthma attacks Increase in restricted activity days Increase in hospital admissions especially respiratory admissions Increase in mortality


The effect of ozone on pulmonary function (after Kleinman et al., 1989): The effect of ozone on pulmonary function (after Kleinman et al., 1989)


Effects of ozone on respiratory symptoms (after Kleinman et al., 1989): Effects of ozone on respiratory symptoms (after Kleinman et al., 1989)


Asthma camp associations between O3 levels and both peak flow lung function change and asthma exacerbations (as indicated by -agonist medication use) (Thurston et al., 1997): Asthma camp associations between O3 levels and both peak flow lung function change and asthma exacerbations (as indicated by -agonist medication use) (Thurston et al., 1997)


Reported RR of respiratory hospital admission associated with a 100 ppb increase in daily 1-h max. O3 (Ito et al., 1999): Reported RR of respiratory hospital admission associated with a 100 ppb increase in daily 1-h max. O3 (Ito et al., 1999)


Reported RR of mortality associated with a 100 ppb increase in 1-h max. O3 (Thurston et al., 1999): Reported RR of mortality associated with a 100 ppb increase in 1-h max. O3 (Thurston et al., 1999)


Nitrogen dioxide – Health effects: Nitrogen dioxide – Health effects Decreases in lung function Increase in respiratory symptoms Increase in hospital admissions – asthma, COPD Increase in mortality – conflicting results


Potential human health effects of NO2: Potential human health effects of NO2 Source: Samet and Utell, 1990


Adjusted prevalence of respiratory infections in children of ten communities in Switzerland according to the mean NO2 level (from Braun-Fahrlander, 1997): Adjusted prevalence of respiratory infections in children of ten communities in Switzerland according to the mean NO2 level (from Braun-Fahrlander, 1997)


Carbon monoxide – health effects: Carbon monoxide – health effects Angina and ischaemic heart disease Hospital admissions – heart disease, asthma Mortality – all cause and heart disease


Relative risks of congestive heart failure admission among Medicare patients as a function of ambient pollutant levels: Relative risks of congestive heart failure admission among Medicare patients as a function of ambient pollutant levels Note: The multipollutant model included all four pollutants. All models included temperature, month, day of week, and year. Values refer to the relative risk associated with an increase of 10 ppm of carbon monoxide. From Morris et al. (1995). Reproduced with permission of authors and publisher.


Sulphur dioxide – Health effects: Sulphur dioxide – Health effects Decrease lung function – in those with asthma Increase in symptoms ED presentations Hospital admissions - respiratory Mortality – all cause, respiratory and CVS


APHEA studies: APHEA studies For a 50 ug/m3 increase in 24 hour average SO2: 3% increase in all cause mortality 4% increase in cardiovascular mortality 5% increase in respiratory mortality 2% increase in respiratory admissions (65+ years)


Types of studies: Types of studies Animal studies Human studies Experimental (chamber studies) Epidemiological (or observational) Cross-sectional Time series Case-control/ Case-crossover Cohort Randomised control trials


Health outcome measures in studies of air pollution: Health outcome measures in studies of air pollution


Some other health endpoints of interest: Some other health endpoints of interest Cardiovascular disease (AMI, heart failure) ECG changes Hospital admissions Mortality Perinatal outcomes Birth weight and gestational age Neonatal and infant mortality Cancer incidence – lung cancer


Determinants of exposure, dose and biologically effective dose that underlie the development of health effects (Modified from Jaakkola et al., 1994): Determinants of exposure, dose and biologically effective dose that underlie the development of health effects (Modified from Jaakkola et al., 1994)


Indirect methods of assessing exposure: Indirect methods of assessing exposure


Some issues in air pollution: Some issues in air pollution Multi- pollutant exposure Low dose exposure Size and composition of particles Threshold effects Shape of the response function Time activity patterns Confounding by season and weather


Uses of exposure response relationships: Uses of exposure response relationships Standard setting and risk assessment Cost benefit analyses Air pollution control programs


Study involving modeled air pollution data: Study involving modeled air pollution data


Slide106: A method for exposure assessment Population Air Pollution Exposure


Slide107: Green Scenarios TEST CASE- 25% reduction in motor vehicle usage - public transport, car pooling, home office


Selected references:: Selected references: Department of Environment and Heritage. (2001) State of the Environment Australia 2001.Canberra, Australia. http://www.erin.gov.au/soe/atmosphere/index.html (accessed October 2003) Department of Environment and Heritage. (2001) State of Knowledge Report: Air toxics and indoor air quality in Australia. Canberra, Australia. ISBN 0 642 54739 4. Holgate ST, Samet JM, Koren HS, Maynard RL. (eds.) (1999) Air pollution and health. Academic Press. London. McMichael AJ. (1993) Planetary overload: Global environmental change and the health of the human species. Cambridge University Press. New South Wales Environment Protection Authority. (2000) New South Wales State of the Environment 2000. http://www.epa.nsw.gov.au/soe/soe2000/index.htm (accessed October 2003) New South Wales Environment Protection Authority. (1998) Action for air. The NSW Government's 25-year air quality management plan. ISBN 0 7313 0160 9. Chatswood, Australia, Environment Protection Authority.


Slide110: Thank You