Transcript Climate Change and Air Quality: What We Can Expect

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 Campbell
Environmental Protection Office
Toronto Public Health
People can
spend a lot
of time
close to
pollution
sources
Presentation Overview
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“Healthy Public Policy”
Areas of activity
Integration of assessment tools
Policy questions of local
significance
Healthy Public Policy
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Fundamental concept in public health
Particularly relevant for environmental threats
to health
Advocates 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
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Exposure assessment and health
risk
Risk communication
Broad determinants of health (e.g.
social aspects)
Exposure Assessment & Health Risk
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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:
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Stack testing to establish emission rates of
PM10, heavy metals including mercury,
dioxins & furans
Ambient air monitoring before & after
crematorium started operations
Dispersion modeling
Comparison of modeled and actual ambient
levels
Benchmarks:
-
Ambient air quality criteria (OMOE)
Toxicological criteria (RfD & RsD from US EPA)
St John’s Crematorium (Toronto)
Results and Conclusions:
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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
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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 if
Coal-Fired
Predicted if
Gas-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*
48*
70
200*
0*
1,933*
2,800*
8,000*
2,800*
Mercury (kilograms)
Carbon Dioxide
(kilotonnes)
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?
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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 risk
To influence decision makers
What’s Involved in Conducting a BOI Study?
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Is a form of risk assessment
Applies risk coefficients from existing
epidemiological studies worldwide
Uses community-specific data on daily
pollution levels
Uses 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 illness
Hb =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
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1,700 premature deaths/year
6,000 hospitalizations/year
Would likely not have occurred when they did
without exposure to air pollution
Preventable
Increases severity or frequency of common
medical conditions and illnesses
Impact of 2000 BOI Study
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Gave rise to first Smog Summit in June 2000
Catalyzed creation of 20/20 The Way to
Clean Air
Initiated low-sulphur fuel purchases by City
Gave rise to further research – Condition
Critical: Fixing our Smog Alert Warning
System
Increased participation in policy discussions
Facilitated NGOs in advocating for clean air
Risk Communication
Studies that influence communication
policies:
 Toronto Air Quality Index - Health Links
Analysis
 Condition Critical: Fixing the Smog
Warning System
 Evaluation of smog advice
The Air Quality Index (AQI)
Increasing severity of
health effects
AQI Scale
Category
0 - 15
Very Good
16 - 31
Good
32 - 49
Moderate
Smog Alert
50 - 99
100+
Poor
Very Poor
At AQI = 50, OMOE
calls Air Quality
Advisory
Mixed Messages
Health Evidence
AQI
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Toronto’s air quality is
“good” or “very good”
almost all the time
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Triggers smog alerts
only in the summer
months
(based on 2000 study)
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Toronto’s air pollution
leads to 1,000
premature deaths and
5,500 hospitalizations
each year
Air pollution affects
health year round
Distribution in Health Outcomes by AQI
Category
(based on 2000 study)
% of Health Outcomes
Health Outcome
Very Good
Good
Moderate
Poor
Premature
Deaths
64
32
3
<1
Respiratory
Hospitalizations
61
35
3
<1
Cardiac
Hospitalizations
47
35
14
4
All Outcomes
58
34
7
1
Why the AQI Misrepresents
Health Risk
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It did not include fine particulates
(PM10/PM2.5)
It is based on out-of-date air quality
standards
It is based on a single “driver” pollutant,
not the total mix of AQI pollutants
Number of days
Days of “Poor” Air Quality in Toronto resulting from
inclusion of PM2.5 in the AQI
18
16
14
12
10
8
6
4
2
0
9
4
5
7
8
10
2
3
1997
PM2.5 not in AQI
1998
1999
2000
Additional days when PM2.5 included in AQI
Evaluation of Smog Advice
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Personal 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
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Air emissions and health status studies
related to Ashbridges Bay Treatment
Plant
Health Impact Assessment –
Designated bus route
Ashbridges Studies
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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 Studies
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Overall, 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 Studies
Policy recommendation arising:
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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
Cumulative impact is:
Total
impact of
all
emission
sources
=
Impact of
current
ambient air
pollution
levels
+
Impact of
modelled
new source
contribution
Environmental Justice Aspects
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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
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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
Outcomes Examined
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Vehicle pollution
Stress (commuting; driving)
Equity issues (who benefits)
Commute time
Accident rates
Integration of Assessment Tools
Policy
Options
Health
Burden
Air
Emissions
Ambient
Levels
How to Deal with Different Health Outcomes?
Pyramid of Health Effects
Toronto Annual Estimates for Inhalable Particulates (PM10)
Premature mortality (acute)
177
Cardiovascular hospitalization
421
Respiratory hospitalizations
597
Adult chronic bronchitis
1,186
Emergency room visits
5,981
Bronchitis in children
11,997
Asthma symptom days
71,930
Some Policy Questions of Local Significance
How does health burden shift if:
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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