Memorandum submitted by the Campaign for
Clean Air in London (CCAL) (AQ 18)
ONE OF THE WORST PUBLIC HEALTH FAILINGS OR
"COVER-UPS" IN MODERN HISTORY WITH OVER 250,000 PREMATURE
DEATHS DUE TO POOR AIR QUALITY IN THE UK UNDISCLOSED OVER 10 YEARS*
INTRODUCTION
1. I am writing on behalf of the cross-party
Campaign for Clean Air in London (CCAL) to submit a memorandum
to the Environment Audit Committee's (EAC's) inquiry into Air
Quality which opened on 21 October and closes on 14 December 2009.
Thank you for the opportunity for do so. The EAC's announcement
of the inquiry can be seen at:
http://www.parliament.uk/parliamentary_committees/environmental_audit_committee/
eacpn211009.cfm
2. The purpose of CCAL is to achieve, urgently
and sustainably, at least World Health Organisation (WHO) recommended
standards of air quality throughout London. CCAL operates under
the auspices of The Knightsbridge Association, an amenity society.
Further details of CCAL's mission and its supporters can be found
at www.cleanairinlondon.org.
3. CCAL supports strongly all the comments
made by ClientEarth and Environmental Protection UK in their responses
to this inquiry (except if in conflict with this letter in which
case this letter prevails):
CCAL calculation for the UK using COMEAP 2009's
6% coefficient and methodology described in Appendix 3. In other
words, the Government seems to have decided not to disclose since
1998 an updated estimate of the number of premature deaths due
to exposure to dangerous airborne particles (PM2.5 or PM10). There
is a separate question as to whether the 250,000 figure is a substantial
underestimate.
SUMMARY
4. No effective strategy: In CCAL's carefully
considered view, the UK does not have an effective strategy to
comply fully with air quality laws and shows no sign of developing
one. The EAC's inquiry is therefore timely.
5. At separate public meetings in November
and December 2009, highly respected members of COMEAP (the Committee
on the Medical Effects of Air Pollution) were referring still
to 8,100 premature deaths per year due to PM10 in urban areas
of Great Britain (Table 1.1 on page 3 of the COMEAP 1998 report).
CCAL can find no other official number disclosed by the Government
for total premature deaths due to PM2.5 or PM10 in the UK since
1998. The COMEAP 1998 report was titled `Quantification of the
Effects of Air Pollution on Health in the United Kingdom' and
recommended a coefficient of 0.75% per 10 µ/m3 PM10 (eg 1.07%
PM2.5) See also:
http://www.advisorybodies.doh.gov.uk/comeap/statementsreports/airpol7.htm
6. CCAL estimates, using COMEAP's 2009 recommendation
of a 6% coefficient per 10 µbg/m3 PM2.5, there were around
35,000 premature deaths due to dangerous airborne particles (PM2.5)
(which would be the same for PM10 based on current government
advice) in the UK in 2005 (and perhaps 51,537). See Appendix 2
and paragraph 25 below.
7. Failings or `cover-up' of the real health
impact: Assuming CCAL is correct, pending a better estimate from
the Government, it is not unreasonable to assume there have been
some 350,000 premature deaths due to PM2.5 and/or PM10 over the
last 10 years compared to the 81,000 premature deaths one might
have assumed from COMEAP or government published figures. In CCAL's
view, this `gap' of over 250,000 may represent one of the biggest
public health failings or `cover-ups' in modern history. Action:
We need clarity now on the actual and Precautionary Principle
figures.
8. CCAL is concerned separately, based on
a close reading of the Peer Review of the COMEAP 2009 report,
that COMEAP may be substantially underestimating the health impact
at 6% per 10 µbg/m3 PM2.5. Higher coefficients of 12%, 15%,
16% and/or 17% are possible.
9. Modeling is not `fit for purpose': The
Government's modeling of air quality concentrations over the last
decade has not been `fit for purpose'. It has pointed and continues
to point to expected sharp reductions in concentrations of dangerous
air pollutants. Each year, the Government registers apparent `surprise'
when actual results show the opposite picture. What is more alarming
is that the UK has justified less monitoring of air pollution
than other countries on the back of its commitment to modeling.
This is not acceptable and again endangers public health and the
successful planning and delivery of an effective strategy to improve
air quality. Action: Future strategy should assume no change in
concentrations under business as usual until modeling is proven
to be reliable.
10. No coherent delivery chain: The almost
total disjunction between the Government's responsibility, on
behalf of the Member State, and the `work towards compliance'
duty on local authorities has been a recipe for failure. In general,
local authorities (and the Mayor of London) seem to have little
appetite to take action they are not required to take. Action:
The Environment Agency should be given national responsibility,
authority, accountability and adequate resources to ensure full
compliance everywhere with air quality laws (perhaps as in the
USA; proposed at Heathrow; and/or in relation now to flooding).
Alternatively or additionally, a very clear chain of delivery
needs to be defined for each layer of government and others. See
also Appendix 5.
11. Next steps: Many steps need to be taken
to improve air quality in the UK and comply fully with air quality
laws. These include: scrapping COMEAP and replacing it with a
body more like the Health Effects Institute in the USA; giving
the Mayor of London sole responsibility for complying immediately
with EU limit values for PM10; using everything including the
`kitchen sink' to ensure full compliance with EU limit values
for nitrogen dioxide (NO2); and launching a major campaign to
build public understanding of the health risks of poor air quality
and the actions needed to minimise them.
12. The opportunity: Protecting public health
and complying with air quality laws also offers many co-benefits.
The UK could show at the 2012 Olympics how air pollution and wider
sustainability issues can be tackled successfully in major cities.
Ridicule is in prospect if air quality is not tackled.
HEALTH AND
ENVIRONMENTAL RISKS
CAUSED BY
POOR AIR
QUALITY
Warning: CCAL has a lay understanding of epidemiology
but has made every reasonable effort to ensure the accuracy of
its statements on health risks.
Health risks—Dangerous airborne particles
(see also Appendix 1)
13. Dangerous airborne particles are usually
categorised by size: fine particles called PM2.5 (less than 2.5
micrograms per cubic metre (?/m3)); coarse particles called PM2.5-10;
and PM10 (less than 10 ?/m3). PM2.5 arises largely from combustion
and PM2.5-10 arises largely from mechanical processes eg tyre
and brake wear. A recent EEA/ETC report estimated that within
Europe about 70% of PM10 comprises PM2.5. ie 0.75% per 10 µbg/m3
PM10 = 1.07% per 10 µbg/m3 of PM2.5.
14. Note: COMEAP's advice is that there
is little risk in the coarse fraction so its health impacts are
often not quantified ie all the risk for PM10 is contained in
PM2.5. Some scientists disagree and consider that toxicity appears
across the PM fraction. CCAL has adopted COMEAP's stance for simplicity
ie the number of premature deaths due to PM2.5 and PM10 is the
same.
15. CCAL's understanding of the timeline
of knowledge about the health risks of PM2.5 and PM10 is set out
in Appendix 1 and more briefly below.
16. In 1998, in its report titled "Quantification
of the Effects of Air Pollution on Health in the United Kingdom",
COMEAP proposed in paragraph 9.18 on page 57 a hazard rate (or
risk coefficient) for short-term exposures of 0.75% per 10 µbg/m3
PM10 as a 24-hour mean for all ages. It felt there was insufficient
data to allow acceptably accurate quantification of [long-term]
health effects.
17. In March 2001, in its report titled
"Statement and Report on Long-Term Effects of Particles on
Mortality", COMEAP proposed a hazard rate (or risk coefficient)
for long-term exposures of 0.1% per 1µbg/m3 drop in annual
mean PM2.5 for those aged 30 years and over (ie 1.0% per 10 µbg/m3).
18. In June 2009, in its report titled "Long-Term
Exposure to Air Pollution: Effect on Mortality", COMEAP proposed
in paragraph xiii on page 3 a hazard rate (or risk coefficient)
for long-term exposures of 6.0% per 10 µbg/m3 increase in
annual mean PM2.5 for those aged 30 years and over.
19. CCAL urges the EAC to consider the Peer
Review comments submitted on COMEAP's draft report (see Appendix
1 of COMEAP 2009) which include serious criticisms of COMEAP's
choice of coefficients and of the elicitation process used by
COMEAP to choose the recommended coefficient:
See: http://www.dh.gov.uk/ab/COMEAP/DH_108151
20. CCAL urges the EAC to consider Defra's
report on the impact of delay in complying with air quality laws
on race. It is titled `UK notification to the European Commission
to extend the compliance deadline for meeting PM10 limit values
in ambient air to 2011, Race Equality Impact Assessment (England)'.
See Appendix 6.
21. CCAL is not aware of any update on the
total societal costs of poor air quality since Table 2.14 on page
90 of the Defra 2007 Air Quality Strategy (AQS):
http://www.defra.gov.uk/environment/quality/air/airquality/publications/stratreview-analysis/chap-2-icgb.pdf
While 6% remains the COMEAP 2009 recommendation,
the range for 2005 societal costs is £8.582 billion to £20.165
billion. The 7 to 8 months average national impact in life expectancy
appeared in the Foreword of the same 2007 AQS.
22. Applying COMEAP 2009 recommendations
using the Precautionary Principle suggests a coefficient of 15%.
Even however at a lower 12%, the societal costs were £16.238
billion to £38.115 billion in 2005 (per Table 2.14 in the
2007 AQS).
Government or COMEAP statements re premature deaths
due to PM2.5 in the UK in 2005
23. At separate public meetings in November
and December 2009, highly respected members of COMEAP were referring
still to a 1998 COMEAP figure of 8,100 premature deaths per year
due to PM10 in urban areas of Great Britain (Table 1.1 on page
3 of the COMEAP 1998 report). CCAL can find no other official
number disclosed by the Government for total premature deaths
due to PM2.5 or PM10 in the UK since 1998. The COMEAP 1998 report
was titled `Quantification of the Effects of Air Pollution on
Health in the United Kingdom'. See also:
http://www.advisorybodies.doh.gov.uk/comeap/statementsreports/airpol7.htm
The public events were the Environmental Protection
UK autumn conference on 12 November 2009 and the Royal Society
of Chemistry's annual conference on 9 December 2009.
CCAL's lay calculation of premature deaths due
to PM2.5 in the UK in 2005
24. The European Topic Centre on Air and
Climate Change estimated in its paper titled `Health Impacts and
Air Pollution—An exploration of factors influencing estimates
of air pollution impact upon the health of European citizens'
in December 2008 estimated that there were 51,537 premature deaths
attributable to exposure to ambient PM10 concentrations in the
UK in 2005 (Table 1.1 on page 8):
See: http://air-climate.eionet.europa.eu/reports/ETCACC_TP_2008_13_HealthImpact_AirPoll
25. CCAL has calculated the number of premature
deaths due to PM2.5 in the UK in 2005 using three separate methods
(see Appendix 2).
26. CCAL estimates that between 33,000 to
40,000 people died prematurely due to PM2.5 (or PM10) in the UK
in 2005 assuming the COMEAP 2009 6% coefficient. The number may
be as high as 51,537 (see paragraph 25 above). Note that levels
of PM2.5 have been broadly static over the last 10 years.
27. Assuming CCAL is correct, pending a
better estimate from the Government, it is not unreasonable to
assume there have been some 350,000 premature deaths due to PM2.5
and/or PM10 over the last 10 years compared to the 81,000 premature
deaths one might have assumed from COMEAP or government published
figures. In CCAL's view, this `gap' of over 250,000 may represent
one of the biggest public health failings or `cover-ups' in modern
history.
28. CCAL is concerned separately, based
on a close reading of the Peer Review of the COMEAP 2009 report,
that COMEAP may be substantially underestimating the health impact
at 6% per 10 µbg/m3 PM2.5. Higher coefficients of 12%, 15%,
16% and/or 17% are possible.
CCAL's lay calculation of premature deaths due
to PM2.5 in London boroughs in 2005
29. CCAL has similarly calculated the number
of premature deaths due to PM2.5 in London in 2005 for each London
borough (Appendices 3 and 3A). CCAL estimates that there were
between 3,500 (assuming a 6% coefficient) and 6,500 (assuming
a plausible 12% coefficient) and 7,900 (using a wider 15% coefficient)
premature deaths due to PM2.5 in London in 2005. The actual numbers
may be around 10% higher depending on average population-weighted
exposures in outer London. These numbers dwarf the 1,031 premature
deaths due to PM10 in 2005 that the Government told Mayor Livingstone
which were based on a coefficient of 0.75% per 10 µbg/m3
increase in PM10 (per COMEAP's 1998 recommendation) (refer to
CCAL letter to Mayor Johnson dated 20 September 2009).
Health risks—Nitrogen dioxide (NO2) (see
also Appendix 4)
30. At Environmental Protection UK's autumn
conference on 12 November 2009, CCAL recollects Professor Jonathan
Ayres, Chairman of COMEAP, making a personal comment (ie not official
COMEAP policy) to the whole meeting that public exposure to ambient
concentrations of nitrogen dioxide in the urban environment is
`irrelevant' for public health. CCAL recollects Professor Ayres
went on to emphasise though that NO2 has the advantage of being
very easy to monitor and it is a reliable indicator of hazardous
vehicle emissions. Despite these important clarifications, CCAL
considers that Professor Ayres' personal comments could be a source
of public confusion and therefore merit clarification from the
Government.
Environmental risks
31. CCAL draws the EAC's attention to the
European Commission's press release dated 12 December 2007 which
included estimates of the cost impact of air pollution on biodiversity.
See:
http://europa.eu/rapid/pressReleasesAction.do?reference=MEMO/07/571&format=HTML&
aged=1&language=EN&guiLanguage=en
Summary health issues and the effective communication
of them
32. A cynic might say that COMEAP in 2009
chose not to increase its coefficient of total mortality for PM2.5,
despite significant new research published n 2005 and 2006, because:
it did not wish to `run' ahead' of WHO advice (2006); the European
Commission's CAFÉ programme; and/or Defra's Air Quality
Strategy (2007). A cynic might also suggest that COMEAP may have
been concerned about presenting health impact coefficients much
higher than those it had identified in 1998 and 2001.
33. CCAL's carefully considered view, influenced
by comments in the Peer Review of COMEAP 2009, is that COMEAP
is likely to have understated (perhaps very substantially) in
2009 the health impact of poor air quality.
34. Further, CCAL considers that the Precautionary
Principle should be followed when public health is at risk. On
this basis, COMEAP's 2009 recommendations point to coefficients
of 12% or 15% per 10 µbg/m3 PM2.5.
35. Irrespective of the correct coefficient
for total mortality, CCAL considers it important to communicate
the health impact of poor air quality appropriately (ie in a manner
which is meaningful and most useful) to different audiences. There
are four common metrics: premature or attributable deaths; total
(eg national) years of life lost (YLL); average reduction in life
expectancy across the whole UK population; and years lost per
statistical victim. In CCAL's experience, premature death and
years of life lost per statistical victim are the most effective
measures to use for communication with the general public. Clearly,
as with all risks, it is important to explain the meaning of the
metric carefully. YLL may be appropriate for economists et al.
36. Please note that CCAL has not mentioned
the health impact of other forms of air pollution in this memorandum
eg ozone (O3) and sulphur dioxide (SO2).
37. In CCAL's view, Londoners should be
warned that up to one person in eight who died in Greater London
in 2005 may have done so due to exposure to dangerous airborne
particles (assuming only average UK population-weighted exposures
in London). Research published in 2001 by Professor Nino Kunzli
suggests that those who die prematurely due to dangerous airborne
particles may do so, on average, 9.8 years early. On this basis,
the health impact of poor air quality in London is similar or
greater to that for alcoholism, obesity and/or smoking.
STEPS THAT
NEED TO
BE TAKEN
TO ENSURE
THAT AIR
QUALITY TARGETS
WILL BE
MET IN
FUTURE
38. Many steps need to be taken to improve
air quality in the UK and comply fully with air quality laws including
those set out below.
39. The Government must `grip' the UK's
serious air quality problem and deliver on its responsibilities.
40. The Government must disclose as a matter
of urgency its assessment of the number of premature deaths due
to dangerous airborne particles (PM2.5) in each region of the
UK in 2005 (or preferably a more recent year) (using at a minimum
COMEAP 2009's 6% coefficient) together with a Precautionary Principle
number (eg the 15% coefficient). Also an estimate of the years
of life lost per statistical victim. These metrics are provided
for other health risks eg obesity and smoking.
41. The Government should scrap COMEAP or
revamp it to ensure its independence, effective governance and
focus on highlighting multiple metrics and adopting explicitly
a faster review of evidence and the use of the Precautionary Principle
approach to protect public health. CCAL would favour replacing
COMEAP with a body more like the Health Effects Institute in the
USA with its Independent Board of Directors (with legal duties).
See: http://www.healtheffects.org/index.html
42. The Government must weigh benefits and
costs against the need to meet air pollution deadlines whether
for air quality or climate change.
43. The Government should give the Mayor
of London legal responsibility for ensuring full compliance with
air quality laws for PM10 immediately.
44. The Government needs to take a strong
lead on ensuring compliance with air quality laws for NO2. In
CCAL's view this may require `every measure available including
the kitchen sink'. See Defra's write up of its NO2 measures workshop
dated 4 August 2009.
45. It is imperative that planning takes
place now to ensure full compliance with air quality laws for
PM2.5 since these are likely to drive public health benefits once
EU limit values for PM10 and NO2 are met.
46. CCAL has proposed 65 recommendations
to improve air quality in London (Appendix 7). Many are relevant
nationally. These include `The London Matrix', `The London Principle'
and `The London Circles'.
47. The Government must maximise economy
of scale benefits by taking an active lead and giving directions
on measures such as inner-city low-emission zones (to avoid national
waste and chaos).
48. The Government must drop its myopic
focus on CO2 to the exclusion of other air pollutants. In particular,
its approach to diesel has been a significant cause of poor quality
in our biggest cities.
49. A major public understanding campaign
should be launched to warn people about the dangers of poor air
quality and the measures individuals can take to reduce its impact.
50. Government should press the European
Commission and the WHO to update urgently (and well before 2013)
their recommendations for the health impact of poor air quality
based on the most up to date scientific research referred to in
this memorandum or otherwise.
51. Protecting public health and complying
with air quality laws will show how air pollution and sustainability
can be tackled successfully. The 2012 Olympics offers an opportunity
to do so.
APPENDIX 1
HEALTH RISKS—DANGEROUS AIRBORNE PARTICLES
52. Dangerous airborne particles are usually
categorised by size: fine particles called PM2.5 (less than 2.5
micrograms per cubic metre (?/m3)); coarse particles called PM2.5-10;
and PM10 (less than 10 ?/m3). PM2.5 arises largely from combustion
and PM2.5-10 arises largely from mechanical processes eg tyre
and brake wear. A recent EEA/ETC report estimated that within
Europe about 70% of PM10 comprises PM2.5. ie 0.75% per 10 µbg/m3
PM10 = 1.07% per 10 µbg/m3 of PM2.5
53. Note: COMEAP's advice is that there
is little risk in the coarse fraction so its health impacts are
often not quantified ie all the risk for PM10 is contained in
PM2.5. Some scientists disagree and consider that toxicity appears
across the PM fraction. CCAL has adopted COMEAP's stance for simplicity
ie the number of premature deaths due to PM2.5 and PM10 is the
same.
54. CCAL's understanding of the timeline
of knowledge about the health risks of PM2.5 and PM10 is set out
below.
55. Initially, scientists considered that
the health impacts of air pollution included respiratory problems
and perhaps cancer. They used time series studies that analysed
the rise in deaths around the time of air pollution `episodes'.
Subsequent research identified the dominance of cardiovascular
disease as a cause of death. Long term, so-called cohort studies,
undertaken over decades have tracked the health impact of PM2.5
and found a lack of `threshold' ie no safe level of exposure.
56. The two studies most widely cited in
the literature are based on the American Cancer Society (ACS)
and Harvard Six Cities cohorts (COMEAP 2009, page 174). The ACS
cohort study followed several hundred thousand people in metropolitan
areas across the USA.
57. In 1998, in its report titled "Quantification
of the Effects of Air Pollution on Health in the United Kingdom",
COMEAP stated in paragraph 9.18 on page 57:
"We have taken as a coefficient of effect
an increase of 0.75% per 10 µbg/m3 PM10 as a 24-hour mean.
On this basis, we estimate that PM10 contributes to the advancement
of around 8,100 deaths in the urban population of Great Britain
annually".
"In the view of this subgroup and COMEAP,
in addition to the effects recorded here, it is likely that long-term
exposure to air pollutants also damages health. At present there
are insufficient data to allow acceptably accurate quantification
of these effects and the sub-group was not confident in applying
UK estimates of exposure-response coefficients from long-term
studies undertaken elsewhere. However, if estimates made elsewhere,
especially in the USA, do apply in the UK, they suggest that the
overall impacts may be substantially greater than those we have
as yet been able to quantify". Paragraph 1.14 on page 3:
See: http://www.advisorybodies.doh.gov.uk/comeap/statementsreports/airpol7.htm
It seems the full report can no longer be purchased
or accessed online. CCAL has a copy.
58. In other words, based on time series
studies, COMEAP 1998 proposed a hazard rate (or risk coefficient)
for short-term exposures of 0.75% per 10 µbg/m3 PM10 as a
24-hour mean for all ages. It felt there was insufficient data
to allow acceptably accurate quantification of [long-term] health
effects.
59. In March 2001, in its report titled
"Statement and Report on Long-Term Effects of Particles on
Mortality", COMEAP stated in paragraph 59 (iv) on page 23:
"Although intended as only a rough comparison,
this does suggest that the gain in life years from the cohort
studies is at least 10 fold greater than estimates from the time
series studies alone".
"For long-term exposures it stated in the
Table in paragraph 10 on page 3 "0.1% based on a 1 µbg/m3
drop in annual mean PM2.5 [for those aged 30 years and over].
Estimate considered most likely to be around this size":
See: http://www.dh.gov.uk/ab/COMEAP/DH_108596
60. In other words, based on cohort studies,
COMEAP 2001 proposed a hazard rate (or risk coefficient) for long-term
exposures of 1.0% per 10 µbg/m3 drop in annual mean PM2.5
for those aged 30 years and over.
61. Kunzli et al (2001) stated in `Assessment
of Deaths Attributable to Air Pollution: Should We Use Risk Estimates
Based on Time Series of on Cohort Studies':
"In our impact assessment, we assumed that
cases' deaths were due to cardiorespiratory disease and that these
air pollution-related deaths had the same age distribution as
all persons who died from cardiorespiratory diseases. Thus, the
amount of time lost, per statististical victim, turned out to
be 9.8 years, which corresponds to a change in life expectancy
of approximately 0.6 years in the total population":
See: http://aje.oxfordjournals.org/cgi/reprint/153/11/1050
Note: Professor Kunzli's 0.6 years (ie 7.2 months)
is very similar to the Government's current seven to eight months
(across 61 million people).
62. Pope et al (2002) proposed in `Lung
Cancer, Cardiopulmonary Mortality, and Long-Term exposure to Fine
Particulate Air Pollution' an average adjusted mortality relative
risk associated with a 10 µbg/m3 change in fine particles
measuring less than 2.5 ?m in diameter of 1.06 (95% CI 1.02-1.11):
See: http://jama.ama-assn.org/cgi/reprint/287/9/1132
63. Jerrett et al (2005) stated in `Spatial
analysis of air pollution and mortality in Los Angeles'. This
study was based on data selected from the ACS cohort for the period
1982-2000:
"After controlling for 44 individual covariates,
all cause mortality had a relative risk (RR) of 1.17 (95% confidence
interval = 1.05-1.30) for an increase of 10 µbg/m3 PM2.5
and a RR of 1.11 (0.99-1.25) with maximal control of both individual
and contextual confounders":
See: http://www.ncbi.nlm.nih.gov/pubmed/16222161
64. COMEAP published an Interim Statement
on 18 January 2006 recommending the use of coefficient based on
the average exposure period reported by Pope et al 2002 as:
"...our best, current, estimate of that
linking PM2.5 and all-cause mortality in the UK' (COMEAP 2009,
page 60)"
"Our interim conclusion is then that the
effects on mortality of long-term exposure to a mixture of air
pollutants, represented by PM2.5, are best characterized by the
following coefficient, expressed in terms of the percentage change
in relative risk of all cause mortality per 10 µbg/m3 change
in annual average PM2.5:
with 95% CI (1.02-1.11)
"We note this represents a change from that
provided in our last report. This reflects the expansion of the
evidence-base in this area and our deeper understanding of the
effects of pollutants, and other factors, on health". COMEAP
2009, page 61:
See: http://www.dh.gov.uk/prod_consum_dh/groups/dh_digitalassets/@dh/@ab/documents/digitalasset/dh_096803.pdf
65. In 2006, the World Health Organisation
published updated global guidelines on air quality. This recommended
a coefficient of 6% per 10 µbg/m3 increase in PM2.5 which
has been used by the European Commission and others in the CAFÉ
(Clean Air for Europe) studies:
See: http://www.euro.who.int/Document/E90038.pdf
66. Laden et al (2006) stated in `Reduction
in Fine Particulate Air Pollution and Mortality, Extended Follow-up
of the Harvard Six Cities Study':
"We found an increase in overall mortality
associated with each 10 µbg/m3 increase modeled either as
the overall mean (rate ratio [RR], 1.16; 95% confidence interval
[CI], 1.07-1.22) or as exposure in the year of death (RR 1.14;
95% CI, 1.13-1.44)":
See: http://ajrccm.atsjournals.org/cgi/reprint/173/6/667
67. In 2007, Defra published its Air Quality
Strategy which adopted the 6% coefficient per 10 µbg/m3 increase
in PM2.5.
68. Pope et al (January 2009) stated in
`Fine-Particulate Air Pollution and Life Expectancy in the United
States':
"A decrease of 10 ug per cubic meter in
the concentration of fine particulate matter was associated with
and estimated increase in mean (+/-SE) life expectancy of 0.61+/-0.20
year":
See: http://content.nejm.org/cgi/reprint/360/4/376.pdf
69. In June 2009, in its report titled "Long-Term
Exposure to Air Pollution: Effect on Mortality", COMEAP stated
in paragraph xiii on page 3:
"Best estimate of 1.06 with 95% confidence
interval 1.02-1.11.
"Our representation of the uncertainty regarding
the coefficient linking the relative risk of death from all-causes
to long-term exposure to PM2.5 is given in the figure.
"For the purposes of conducting impact assessments
regarding all-cause mortality and assessing policy interventions
designed to reduce levels of air pollutants, we have recommended
that the full distribution of probabilities be used as an input
into Monte Carlo analysis, the approach we favour. Alternatively,
we suggest that the plausible `low' and `high' values of 1.01
and 1.12, respectively, based approximately on the 12.5% and 87.5%
percentiles of the overall range of plausibility, could be used
in sensitivity analyses.
"We also recommend that the wider interval
of 0 to 15% (relative risk 1.00 and 1.15) be included in any report
on quantification of risks from long-term exposure to particulate
air pollution represented by PM2.5":
See: http://www.dh.gov.uk/ab/COMEAP/DH_108151
COMEAP went on to state on page 60:
"We have chosen the coefficient based on
the averaged exposure period reported by Pope et al (2002) as
our best estimate, current, estimate of that linking PM2.5 and
all-cause mortality in the UK. This coefficient is based on the
largest available cohort study".
70. Commenting on this and other criticism
of it for excluding key scientific research, COMEAP stated in
paragraph 1 on page 179 "A cut-off date of early 2006 was
adopted for published work which was considered in detail. We
note that this, unfortunately, excludes an important and influential
review by Pope and Dockery (2006) and recommend reading of that
review to readers of this report".
71. In other words, based on cohort studies,
COMEAP 2009 proposed a hazard rate (or risk coefficient) for long-term
exposures of 6.0% per 10 µbg/m3 increase in annual mean PM2.5
for those aged 30 years and over.
72. CCAL urges the EAC to consider the Peer
Review comments submitted on COMEAP's draft report (see Appendix
1 of COMEAP 2009) which include serious criticisms of its choice
of coefficients and of the elicitation process used by COMEAP:
See: http://www.dh.gov.uk/ab/COMEAP/DH_108151
73. CCAL urges the EAC to consider Defra's
report on the impact of delay in comply with air quality laws
on race. It is titled `UK notification to the European Commission
to extend the compliance deadline for meeting PM10 limit values
in ambient air to 2011, Race Equality Impact Assessment (England)'.
74. CCAL is not aware of any update on total
societal costs since that in Table 2.14 on page 90 of Defra's
Air Quality Strategy 2007 (AQS):
http://www.defra.gov.uk/environment/quality/air/airquality/publications/stratreview-analysis/chap-2-icgb.pdf
While 6% remains the COMEAP 2009 recommendation,
the range for 2005 societal costs is £8.582 billion to £20.165
billion. The seven to eight months appeared in the Foreword of
the same Defra AQS.
75. Applying COMEAP 2009 recommendations
using the Precautionary Principle suggests a coefficient of 15%.
Even however at a lower 12%, the societal costs were £16.238
billion to £38.115 billion in 2005 (per Table 2.14 in the
Defra AQS referred to above).
APPENDIX 2
CCAL's LAY CALCULATION OF PREMATURE DEATHS
DUE TO PM2.5 IN THE UK IN 2005
76. The European Topic Centre on Air and
Climate Change estimated in its paper titled `Health Impacts and
Air Pollution—An exploration of factors influencing estimates
of air pollution impact upon the health of European citizens'
in December 2008 that there were 51,537 premature deaths attributable
to exposure to ambient PM10 concentrations in the UK in 2005 (Table
1.1 on page 8):
See: http://air-climate.eionet.europa.eu/reports/ETCACC_TP_2008_13_HealthImpact_AirPoll
77. CCAL has calculated the number of premature
deaths due to PM2.5 in the UK in 2005 using three separate methods.
CCAL's first estimate—The European Environment Agency's
report titled `Spatial assessment of PM10 and ozone concentrations
in Europe (2005)' provides (in Figure 3.4 on page 20) an estimate
of around 650 premature deaths per million ie 61 times 650 = 39,650
premature deaths due to PM10 (or PM2.5) in the UK in 200:
See: http://www.eea.europa.eu/publications/spatial-assessment-of-pm10-and-ozone-concentrations-in-europe-2005-1
78. CCAL's second estimate is based on the
methodology in its letters to Mayor Johnson dated 20 September
and 17 November 2009 respectively.
The total number of UK deaths (all ages) in
2005 was 582,700 (Annex B, Table B1 on page 97 of the report via
the link below):
http://www.statistics.gov.uk/downloads/theme_population/KPVS32_2005/KPVS2005.pdf
Less 1.9% to get deaths of people aged 30 and
above (per CCAL letter to Mayor Johnson dated 17 November) = 571,629
deaths.
Exposed to 10.144 µbg/m3 PM2.5 as the UK
population-weighted average for 2005 (see Appendix 3).
Gives for PM2.5 and PM10 (ie assuming PM2.5
and PM10 premature deaths are the same as seems to be current
government policy):
| 6% adjusts to 5.74% |
= | 32,811 premature deaths |
| 12% adjusts to 10.86% | = |
62,079 premature deaths |
| 15% adjusts to 13.22% | = |
75,569 premature deaths |
| | |
Therefore, assuming COMEAP's 6% coefficient (2009) gives
32,800 premature deaths for 2005 using the same 6% assumption
and the same other parameters (ie 10.144 µbg/m3 of anthropogenic
(ie man-made) PM2.5) used in the Defra AQS 2007.
79. CCAL's third estimate uses the methodology indicated
by Professor Kunzli et al (2001):
A calculation of the equivalent to 7 to 8 months across 61
million people.
Using (say) 7.5 months, as the average for 61 million people,
CCAL calculates:
(Premature deaths in 2005) x (105 x 9.8 x 12) = (7.5 months
x 61m). Hence, premature deaths for 2005 constant levels of PM2.5
is 37,050.
Where 105 is the number of years for the whole cohort to die
and 9.8 is the average life lost per victim and 12 converts it
to months.
80. CCAL therefore estimates that between 33,000 to 40,000
people died prematurely due to PM2.5 (or PM10) in the UK in 2005
assuming COMEAP 2009's 6% coefficient. The number may be as high
as 51, 537.
81. Assuming CCAL is correct, pending a better estimate
from the Government, it is not unreasonable to assume there have
been some 350,000 premature deaths due to PM2.5 and/or PM10 over
the last 10 years compared to the 81,000 premature deaths one
might have assumed from COMEAP or government published figures.
In CCAL's view, this `gap' of over 250,000 may represent one of
the biggest public health failings or `cover-ups' in modern history.
82. CCAL is concerned separately, based on a close reading
of the Peer Review of the COMEAP 2009 report, that COMEAP may
be substantially underestimating the health impact at 6% per 10
µbg/m3 PM2.5. Higher coefficients of 12%, 15%, 16% and/or
17% are possible.
APPENDIX 3
AGREED CALCULATION OF PREMATURE DEATHS DUE TO PM2.5 IN
LONDON IN 2005
CCAL and the Health Protection Agency (HPA) have used national
average annual PM2.5 concentrations from Defra's Air Quality Strategy
2007 to calculate the Attributable Deaths in London in 2005 due
to exposure to PM2.5 and the following further assumptions:
(i) London has the same anthropogenic PM2.5 (ie man-made fine
particles) annual average population-weighted mean as the whole
UK of 10.144 µbg/m3 (gravimetric) (see Table 2.11 on page
87 of Volume 3 of Defra's Air Quality Strategy 2007) in 2005.
(ii) http://www.defra.gov.uk/environment/quality/air/airquality/publications/stratreview-analysis/chap-2-icgb.pdf
(iii) Note that Defra assumed (on page 87) the level of non-anthropogenic
PM2.5 to be constant and estimated it to be about 3.37 µbg/m3
annual average population-weighted mean.
(iv) Dr Heather Walton of the Health Protection Agency confirmed
in a presentation to the Air Quality Summit held on 30 November
2009 that Inner London is estimated to have exposure levels for
PM2.5 50% higher than the UK national average ie 15.216 µbg/m3;.
(v) 52,995 total deaths in London in 2005 from Table 4.1b
on page 57 of National Statistics: Key Population and Vital Statistics,
Local and Health Authority Areas. These deaths comprised 17,650
in Inner London and 35,345 in Outer London. See: http://www.statistics.gov.uk/downloads/theme_population/KPVS32_2005/KPVS2005.pdf
(vi) The death rate of those dying before 30 years of age
as 1.9% of total deaths from Table 6.1 on page 47 of National
Statistics, Population Trends, No. 124, Summer 2006. See: http://www.statistics.gov.uk/downloads/theme_population/PT124.pdf
(vii) Calculated that there were 52,995 x (1—0.019)
= 51,988 total deaths in London in 2005 of people aged 30 and
above split between 17,315 in Inner London and 34,673 in Outer
London; and
(viii) Applied the recommendations from COMEAP's 2009 Report
to use a coefficient of 6% per 10 µbg/m3 of PM2.5 as the
best estimate of Attributable Deaths, with a sensitivity of 12%
and a wider interval of 15% (which COMEAP said should be used
in any report on quantification of risks from long-term exposure
to air pollution represented by PM2.5).
The calculation of premature deaths is explained in the footnote
on page 46 of the COMEAP 2009 Report. It says:
"If the new concentration change in population-weighted
mean for the policy interest is -x µbg/m3 (with a negative
sign as the analysis usually concerns reductions), then the new
RR [Relative Risk] for an x µbg/m3 reduction is calculated
as 1.06-x/10 [assuming 1.06 is the RR for a 10 µbg/m3 increase
in PM2.5]. As the equation represents a curved relationship, concentration
increments need to be identified as increases or decreases—the
new RR will have a different value for a given concentration increment
depending on whether it is for an increase or a decrease".
CCAL and the HPA have therefore used the above log-linear
function to scale the results to ensure an accurate number and
applied the resulting RR to the number deaths of people of 30
years of age and older.
The agreed calculations for London in 2005 using the different
coefficients and assuming 1.5 times UK average population-weighted
exposures for Inner London and 1.0 times for Outer London are:
| 6%: | Attributable Deaths = 17,315 x (1—1.06-15.216/10.000) + 34,673 x (1—1.06-10.144/10.000) = 3,459
|
| 12%: | Attributable Deaths = 17,315 x (1—1.12-15.216/10.000) + 34,673 x (1—1.12-10.144/10.000) = 6,508
|
| 15%: | Attributable Deaths = 17,315 x (1—1.15-15.216/10.000) + 34,673 x (1—1.15-10.144/10.000) = 7,900
|
| |
Previously CCAL had simply applied the RRs of 1.06, 1.12
and 1.15 figures for the 10.144 µbg/m3 reduction in PM2.5
as indicated on page 46 of the COMEAP Report 2009 can be done
as an approximation. The differences for a 15.216 µbg/m3
and 10.144 µbg/m3 reduction in PM2.5 become:
Instead of 6%: 1—1.06-15.216/10.000 = 8.48%
1—1.06-10.144/10.000 = 0.0574 ie 5.74%
Instead of 12%: 1—1.12-15.216/10.000 = 15.84% 1—1.12-10.144/10.000
= 0.1086 ie 10.86%
Instead of 15%: 1—1.15-15.216/10.000 = 19.16% 1—1.15-10.144/10.000
= 0.1322 ie 13.22%
APPENDIX 4
HEALTH RISKS—NITROGEN DIOXIDe (NO2)
83. At Environmental Protection UK's autumn conference
on 12 November 2009, CCAL recollects Professor Jonathan Ayres,
Chairman of COMEAP, making a personal comment (ie not official
COMEAP policy) to the whole meeting that public exposure to ambient
concentrations of nitrogen dioxide in the urban environment is
`irrelevant' for public health. CCAL recollects Professor Ayres
went on to emphasise though that NO2 has the advantage of being
very easy to monitor and it is a reliable indicator of hazardous
vehicle emissions. Despite these important clarifications, CCAL
considers that Professor Ayres' personal comments could be a source
of public confusion and therefore merit clarification from the
Government.
84. In a written question on 27 October 2009, Lord Berkeley
asked:
"To ask Her Majesty's Government what harmful air pollutants
are likely to be present in ambient air when concentrations of
nitrogen dioxide (NO2) are high; and in what proportions".
85. Lord Davies of Oldham replied in a statement:
"Nitrogen dioxide (NO2) arises directly and indirectly
from combustion processes. Concentrations are generally highest
close to their emission sources, primarily road transport followed
by the power generation industry and other industrial and commercial
sector sources.
"The nature of the combustion processes and fuel used
will determine the presence of other pollutants, such as particulate
matter, polycyclic aromatic hydrocarbons, benzene, carbon monoxide
and sulphur dioxide. It is not possible to define the proportions
that these pollutants may be present in at any particular location
at any one time. Proportions will vary with time, the distance
from sources, meteorology, and chemistry depending on the type
of combustion processes and emissions released":
See: http://www.theyworkforyou.com/wrans/?id=2009-10-27a.138.0
86. Please see COMEAP's statement on the quantification
of the effects of long-term exposure to nitrogen dioxide on respiratory
morbidity in children (October 2009):
See: http://www.dh.gov.uk/ab/COMEAP/DH_108150
87. Please note that WHO confirmed in 2006 its concerns
about the health impact of exposure to NO2. In this respect, Dr
Michal Krzyzanowski (who lead that report) expressed a personal
view to CCAL that there has been much less research into the health
effects of NO2 than that for PM2.5 and PM10. He commented similarly
to CCAL that NO2 concentrations should not be made worse by measures
to reduce other pollutants.
88. Please note that recent research by David Carslaw
that indicates NO2 levels may not fall as levels of oxides of
nitrogen (NOx) fall eg with newer standards for European vehicle
emissions.
APPENDIX 5
THE DELIVERY CHAIN FOR AIR QUALITY
89. The almost total disjunction between the Government's
responsibility, on behalf of the Member State, and the `work towards
compliance' duty on local authorities is a recipe for failure.
In general, local authorities (and the Mayor of London) seem to
have little appetite to take action they are not required to take.
Action: The Environment Agency should be given national responsibility,
authority, accountability and resources to ensure full compliance
everywhere with air quality laws (perhaps as in the US, proposed
at Heathrow and in relation now to flooding. Alternatively, a
very clear chain of delivery needs to be defined for each layer
of government.
90. Britain's Transport Infrastructure Adding Capacity
at Heathrow: Decisions Following Consultation published by the
Department for Transport in January 2009 paragraph 64 on page
24 stated:
"On air quality, the Environment Agency would be responsible
for overseeing monitoring and analysing air quality data. Because
background emissions, emissions from surface transport, both airport-related
and non-airport-related, and aviation emissions are contributory
factors to air quality around Heathrow, the Agency would report
any breaches to both Secretaries of State. The CAA, in respect
of noise, and the Environment Agency, in respect of air quality,
will have the necessary powers to ensure that relevant parties
take their share of the remedial action needed to comply with
the respective legal limits. The Agency would take account of
its duties and relevant guidance provided by the Secretary of
State for Environment, Food and Rural Affairs, in agreement with
the Secretary of State for Transport":
http://www.dft.gov.uk/pgr/aviation/heathrowconsultations/heathrowdecision/decisiondocument/decisiondoc.pdf
91. Defra Air Quality Forum on 24 February 2009 minutes:
"CCAL were concerned that the Mayor for London and local
authorities were only required to work towards the achievement
of the air quality objectives. They suggested that the Secretary
of State should issue a direction under the legislation, which
stated that "at a minimum, the Mayor and the local authorities
should commit to use their best efforts to implement successfully
actions to improve air quality in London, when it exceeds limit
values, which are meaningful when judged in the context of all
their available powers and the deadlines applicable under UK and
European law". CCAL considered this would allow the necessary
actions to be enforceable by various people at local and national
level":
http://www.defra.gov.uk/environment/quality/air/airquality/panels/forum/documents/aqforum-minute-090224.pdf
13 December 2009
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