Towards Healthy Public Policy:Assessing & Mitigating Health Burden from Air Policy Analysis for Air Quality and Health Workshop at Metro Hall, Toronto – May 19, 2005

Monica CampbellEnvironmental Protection OfficeToronto Public Health

People can spend a lot of time close to pollution sources

Presentation Overview

“Healthy Public Policy” Areas of activity Integration of assessment tools Policy questions of local

significance

Healthy Public Policy

Fundamental concept in public healthParticularly relevant for environmental threats

to healthAdvocates for shifts in public policies that

adversely impact health (eg. transportation, energy, urban form)

Need good assessment tools

Areas of Activity in Influencing Policies Related to Air

Exposure assessment and health risk

Risk communicationBroad determinants of health (e.g.

social aspects)

Exposure Assessment & Health Risk

Local point sources of community concern- St. John’s Crematorium (2000)- Lakeview coal-fired power plant (2000)

Ambient air pollution- Toronto Air-Pollution Burden of Illness study (2004)

St John’s Crematorium (Toronto)Method:

Stack testing to establish emission rates of PM10, heavy metals including mercury, dioxins & furans

Ambient air monitoring before & after crematorium started operations

Dispersion modelingComparison of modeled and actual ambient levelsBenchmarks:

- Ambient air quality criteria (OMOE)- Toxicological criteria (RfD & RsD from US EPA)

St John’s Crematorium (Toronto)Results and Conclusions:

Crematorium actual and modelled emissions were very low and far below provincial standards

Worst-case concentrations were at most 1% of AAQC and 25% of health criteria

Background levels of PM10 high and sometimes exceeded provincial standard but crematorium contribution very small

Lakeview Coal-Fired Power Plant

Modelling study (2000) to estimate ambient concentrations of NOx and SO2 with different operating conditions

Lakeview (1997 base year operating at 19% capacity) found to contribute:< 0.3% of ambient annual NOx in GTA;< 9.2% of ambient annual SO2 in GTA.

Annual Air Emissions from Lakeview Plant

1997 1998 Predicted ifCoal-Fired

Predicted ifGas-Fired

Operating Capacity 19% 28% 80% 80%

Electrical Generation(GW-h)

1,933 2,800 8,000 8,000

Sulphur Dioxide (tonnes) 13,420 18,820 45,600* 0*

Nitrogen Oxides (tonnes) 5,480 7,820 21,600* 2,000*

Mercury (kilograms) 48* 70 200* 0*

Carbon Dioxide(kilotonnes)

1,933* 2,800* 8,000* 2,800*Annual Emissions, Emission Rates & Operating Capacity provided by Environment Canada;Full Capacity – 1,140 MW x 8760 hours = 9.9864 million MWh (*Estimates)

Air Pollution Burden of Illness Study

Why Do One?

To estimate magnitude of health impact in cost-effective manner

To provide health status information on which to base public health programs

To communicate health riskTo influence decision makers

What’s Involved in Conducting a BOI Study?

Is a form of risk assessmentApplies risk coefficients from existing

epidemiological studies worldwideUses community-specific data on daily

pollution levelsUses community-specific data on adverse

health outcomes such as hospitalizations and mortality (e.g. for respiratory and cardiac causes)

Calculating Burden of Illness

Hp(outcomes/yr) = Hb x Fp

Where:Hp =estimated air-pollution burden of illnessHb =background rate of adverse health outcomes/year

Fp =fraction due to air pollution (Fp= Hp/unit x P; where Hp/unit is the ‘risk coefficient’

per unit pollutant from published epidemiological studies, and P is the effective annual pollutant concentration)

Air Pollution Burden of Illness - Toronto

1,700 premature deaths/year 6,000 hospitalizations/year Would likely not have occurred when they did

without exposure to air pollutionPreventable Increases severity or frequency of common

medical conditions and illnesses

Impact of 2000 BOI Study

Gave rise to first Smog Summit in June 2000Catalyzed creation of 20/20 The Way to Clean

AirInitiated low-sulphur fuel purchases by CityGave rise to further research – Condition

Critical: Fixing our Smog Alert Warning SystemIncreased participation in policy discussionsFacilitated NGOs in advocating for clean air

Risk Communication

Studies that influence communication policies:Toronto Air Quality Index - Health Links

AnalysisCondition Critical: Fixing the Smog

Warning System Evaluation of smog advice

The Air Quality Index (AQI)

AQI Scale Category

0 - 15

16 - 31

32 - 49

50 - 99

100+

Very Good

Good

Moderate

Poor

Very Poor

Smog Alert

At AQI = 50, OMOEcalls Air Quality Advisory

Incr

easi

ng s

ever

ity o

f he

alth

effe

cts

Mixed Messages

Toronto’s air quality is “good” or “very good” almost all the time

Triggers smog alerts only in the summer months

Toronto’s air pollution leads to 1,000 premature deaths and 5,500 hospitalizations each year

Air pollution affects health year round

AQI Health Evidence(based on 2000 study)

Distribution in Health Outcomes by AQI Category

(based on 2000 study)

% of Health OutcomesHealth Outcome

Very Good Good Moderate Poor

PrematureDeaths 64 32 3 <1

RespiratoryHospitalizations 61 35 3 <1

CardiacHospitalizations 47 35 14 4

All Outcomes 58 34 7 1

Why the AQI MisrepresentsHealth RiskIt did not include fine particulates

(PM10/PM2.5)It is based on out-of-date air quality

standardsIt is based on a single “driver” pollutant,

not the total mix of AQI pollutants

Days of “Poor” Air Quality in Toronto resulting from inclusion of PM2.5 in the AQI

7 810

3

5

9 4

2

02468

1012141618

1997 1998 1999 2000

Num

ber o

f day

s

PM2.5 not in AQI Additional days when PM2.5 included in AQI

Evaluation of Smog AdvicePersonal exposure monitoring that compares ‘typical day’

exposures to PM<1, PM2.5, VOCs and ozone levels among paired scenarios of individuals who did or did not follow smog alert advice

Tries to understand how much total daily exposures can be reduced by shifting individual behaviours

Collaboration among Chemical Engineering & Applied Chemistry at U of T, Health Canada, Environment Canada and Toronto Public Health

Incorporating Broad Determinants of Health: Social Aspects

Air emissions and health status studies related to Ashbridges Bay Treatment Plant

Health Impact Assessment – Designated bus route

Ashbridges Studies

Air emissions study modelled 17 key pollutants under 4 scenarios, including with full incineration and no incineration at sewage treatment plant

Health status study examined mortality, hospitalization and cancer rates in South Riverdale and Beaches community, in comparison to SES- matched communities

Ashbridges StudiesOverall, the emissions profile improved over time

as incinerator use was phased out and with projected improvements for odour control (including fugitive emissions)

Both communities had higher mortality and hospitalization rates (overall) than their respective comparison communities

South Riverdale has been burdened with more illness and pollution sources than other communities, although it is not possible to suggest a causal relationship

Ashbridges StudiesPolicy recommendation arising:

That the OMOE considers the cumulative impact of emissions from any new or modified industrial facility on adjacent residential areas with elevated rates of illness or mortality prior to issuing a C of A

‘Cumulative’ currently means taking into account all emission sources from a facility

TPH Perspective on Cumulative Impact

Total impact of

all emission sources

Impact of current

ambient air pollution

levels

Impact of modelled

new source contribution

= +

Cumulative impact is:

Environmental Justice Aspects

Should consider integrating social dimensions such as environmental justice concepts when developing public policy

Environmental justice concepts can lead to an examination of spatial distribution of pollution sources and correlations with community characteristics such as income levels, minority status or ethnicity.

Can take into account that people of lower income are more likely to be exposed to air pollution and likely more susceptible to adverse effects from air pollution

Health Impact Assessment

Methodology may be quantitative but typically includes a qualitative assessment of social aspects

HIA results supported introduction of congestion charges (“toll roads) in London, England

Toronto Public Health is completing a pilot HIA on the designated bus route planned to connect subway users to York University

Rapid Bus Route Pilot Health Impact Assessment

Vehicle pollutionStress (commuting; driving)Equity issues (who benefits)Commute timeAccident rates

Outcomes Examined

Integration of Assessment Tools

Policy Options

Air Emissions

Health Burden Ambient

Levels

How to Deal with Different Health Outcomes?

Premature mortality (acute)177

Cardiovascular hospitalization421

Respiratory hospitalizations597

Adult chronic bronchitis 1,186

Emergency room visits 5,981

Bronchitis in children

11,997

Asthma symptom days 71,930

Pyramid of Health Effects Toronto Annual Estimates for Inhalable Particulates (PM10)

Some Policy Questions of Local Significance

How does health burden shift if:

Network of surface designated transit lanes introduced? Road congestion pricing is introduced? Bicycle network is created that reduces space for cars? Older vehicles are required to be retrofit or retired? Zoning is changed to reduce urban sprawl? Existing point sources are required to meet health-based air

quality standards? Comprehensive energy conservation plan is implemented? Coal-fired power plants are replaced with natural gas?

For More Information

Visit our Healthy People Healthy Environment home page at:

www.toronto.ca/health/hphe