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ITEM EX5
Supplement

EXECUTIVE – 7 DECEMBER 2004

AIR POLLUTION – SCRUTINY REVIEW

Supplementary Report from the Scrutiny Review Group

As was mentioned at the City Executive Board meeting on 30 December, it has been drawn to our attention that our report does contain some misconceptions and misplaced emphasis. The text which follows seeks to clarify the position. It is put forward with the benefit of advice from the service officers of the two Councils.

We are satisfied that these points of clarification do not impact on the recommendations in our report, which we commend to you.

The required process and framework for air quality management:

1. Air quality management policy is clear, local government has duties prescribed under Part IV of the Environment Act 1995, that includes a statutory framework within which local authorities have to work. Health based air quality objectives are defined for seven pollutants in UK air quality regulations (Air Quality(England) Regulations 2000 (as amended)), and UK National Air Quality Strategy. The health based standards are derived from World Health Organisation Guidelines and European Union Directives.
2. The process of air quality management in Oxford has involved assessing local air quality in two stages, in relation to the pollutants defined in the National Air Quality Strategy, defining areas and sources of pollution, where any air quality objectives are exceeded.
3. Round 1 of the Local Review and Assessment Process involved three separate reports, Stage 1&2, Stage 3, and Stage 4. These reports were carried out between 1999 and 2003. These reports were based upon emissions data heavily dependent upon modelled traffic data. The overall conclusion confirmed between stages 3 and 4, was that air quality close to trafficked streets, with some nearby housing, in central Oxford would not meet the annual mean objective for nitrogen dioxide in 2005 of 40 microgrammes per cubic metre. Following public consultation on the results of the Stage 3 report, the City Council declared an Air Quality Management Area (AQMA) in September 2001.
4. Following the Stage 4 report, the extent of the AQMA was slightly extended. It was confirmed that emissions from motor vehicle traffic was the major contributor to the local pollution problem. The Stage 4 report contained a series of measures for consideration in an action plan, with predictions of air quality improvements attributable to each measure.
5. The Local Air Quality Management process guidance was revised in 2003 (LAQM PG(03)). This enabled a review of the process to include a second round of air quality reviews and assessments, designed to facilitate a continuous annual review process where air quality problems exist, development of action plans, and integration into Local Transport Plans (LTP’s).
6. The intervention of OTS centred on the measures introduced in 1999, led to major revisions in the patterns of local traffic, leading to a revised local traffic model. Data from the revised traffic model was incorporated in the Stage 4 report for central Oxford, but revised data for the ring road was not assessed until Round 2 of the local air quality review process.
7. Round 2 reports, the Updating and Screening Assessment, and Detailed Assessment (DA) were carried out during 2003-4. These reports began the review process afresh and identified busy trafficked junctions as additional sources of additional AQMA’s in Oxford. The DA report currently subject to public consultation identifies housing areas close to some busy junctions, notably in the vicinity of Green Road Roundabout that are recommended for inclusion as a new AQMA. The USA report highlighted there could be more junctions with localised air quality exceedences that have yet to be identified.
8. The DA report also indicated that long term local air quality issues are not confined to nitrogen dioxide. The reduction of the annual standard for particulate matter for 2010 means that levels of particulate matter require long term monitoring. Recent Airwatch reports also show that objectives for ozone are not being achieved. The combination of exceedences of objectives for nitrogen dioxide, particulate matter and ozone is recognised by DEFRA as a typical pattern of pollution in urban areas within the UK.

To clarify the position in paragraphs 1 and 5:

9. There are 2 standards for nitrogen dioxide in the National Air Quality Strategy:

The Annual Mean standard	40 µg/m3 (21ppb)	This standard is to protect against long-term damage. It is based on a safe level for a person to be exposed to, on average, over the long term.
The Hourly standard 18 exceedences of this level are allowed in each year. That is to say that 98% of the hours in a year the nitrogen dioxide must be below this level.	200 µg/m3 (105ppb)	This standard is to protect against short-term irritation. It seems to be safe to breath air at this level for an hour or two each day so long as the average exposure over a year is less than 40 µg/m3.

10. Exceedences for Nitrogen Dioxide are at roadside locations in the central streets and some busy junctions outside the central area; levels at background sites are within the standards for hourly and annual average for nitrogen dioxide. The National Air Quality Strategy specifies that the hourly standard is more relevant for roadside sites. Further advice and discussion should be sought on appropriate standards for development of the action plan. The most recent reports on local air quality conducted by the City Council establish that the annual objective for nitrogen dioxide is exceeded in central Oxford but the hourly objective is also predicted to be exceeded in some of the busy trafficked streets in central Oxford. The DA report also confirmed that eight city centre streets included within the AQMA are also predicted to have exceedences of the hourly mean objective of 200 microgrammes per cubic metre. (The regulations allow for 18 exceedences of the hourly mean).
11. Paragraph 15, illustrated by the graph on the front cover of the report, includes a comparison of diurnal averages at one city centre roadside site with the NAQS annual mean. Such a comparison is misleading. Full details of comparisons of local air quality to national guidelines and objectives can be found in the Airwatch 2003 report. For nitrogen dioxide there were 11 days in 2003 when objectives were exceeded, but none for 2002. 2003 was an exceptional year due to weather conditions, with similar high levels and increases recorded not only in the rest of the UK, but also throughout Western Europe. High levels of ozone caused by hot, sunny weather in June, July and August when temperatures reached record highs were mainly to blame. A significant amount of the poor air quality was caused by pollution blown in to the UK from abroad as well as local sources. The results of continuous monitoring in Oxford indicated an air quality objective had been exceeded as follows:

	2002	2003
nitrogen dioxide	0 days	11 days
ozone	17 days	54 days
particulate matter	3 days	8 days




12. The table below illustrates the recorded levels for Nitrogen Dioxide at Oxford Centre (St Aldates), noting that where exceedences have been recorded they are still in the LOW band as defined by DEFRA:

Oxford centre summary nitrogen dioxide 2003, 2002,

standard	Nitrogen Dioxide 2003 ppb (µg/m3)	Nitrogen Dioxide 2002 ppb
Mean Max hour data capture	37 (72) 136 (260) 98.2	31 104 99.2
DEFRA band (hrs) Low Moderate High Very High	8599 0 0 0	8691 0 0 0
Air Quality Regulations/Strategy number of exceedences: hourly mean annual mean	23 Exceeded	0 Exceeded

Definition of effect : DEFRA Air Pollution Bands (Air Quality Standards and Guidelines)

• When air pollution is LOW (1-3) effects are unlikely to be noticed even by those who are sensitive to air pollution. • When air pollution is MODERATE (4-6) sensitive people may notice mild effects but these are unlikely to need action. • When air pollution is HIGH (7-9) sensitive people may notice significant effects and may need to take action. • When air pollution is VERY HIGH (10) effects on sensitive people, described for HIGH pollution, may worsen. Air pollution can cause short-term health effects to sensitive individuals (people who suffer from heart disease or lung diseases, including asthma). Effects on sensitive people can be reduced by spending less time outdoors. 'Reliever' inhalers should lessen effects on asthma sufferers.

13. Paragraph 18 refers to 160 premature deaths due to pollution during December 1991. During that episode the levels reached at an urban background site peaked at 423 ppb (809μg m^-3) (p.50 Urban Air Quality in the United Kingdom QUARG 1993.) This is roughly 4 times the highest levels ever measured at any Oxford kerbside site. The reference to the December 1991 episode and to COMEAP’s estimate of deaths associated with PM10 gives the misleading impression that the health impacts of air pollution in Oxford are in some way comparable.
14. There are numerous studies and reports available accepted by UK government, that relate the health impact of increased urban exposures to particulate matter. The smaller fraction of particulate matter PM2.5 that is not routinely monitored in Oxford has been recently equated with an average reduction in life expectancy of six months for the UK population as a whole.(EU café report 2004). It would be expected that higher exposures in urban areas would give rise to higher levels than this.
15. Paragraph 21 discusses increases in nitrogen dioxide emissions in 9 of the 24 modelled street sections. The exercise of modelling is undertaken to aid understanding of the impact of behaviour of traffic on air quality, such as stopping and starting vehicles and localised congestion an increase in emissions does not necessarily equate to a similar change in air quality. When considering central Oxford as a whole, OTS has led to significant reductions in traffic emissions. However when taken on a street by street basis the changes in flows and mix of traffic has led in some cases to increases in emission, and subsequent air pollution has also been shown to increase in some streets, despite overall reduction in central Oxford. The result is a mixed picture in terms of the effect on air quality that have been seen since the introduction of OTS. In line with national trends there has been a small improvement in local air quality measured in Oxford year on year. The Oxford roadside concentrations measured show an average reduction of 2.2% per year in annual mean nitrogen dioxide. The hot summer of 2003 resulted in an average 10% increase in monitored levels of annual nitrogen dioxide at roadside sites, with increases in the number of hourly exceedence.
16. Paragraph 22 contains a table stating the level of emission by class without stating traffic composition for the same area. Table 2 is amended to include traffic composition in the AQMA:

Members of the Lead Member Review Group:

Councillor Jean Fooks
Councillor Biddy Hudson
Councillor Leslie Sibley
Councillor Susanna Pressel
Councillor Tony Hollander

December 2005

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