Memorandum submitted by the Institute of Air Quality Management (AQ02)


The monitoring and modelling of air quality in the UK is, in general, adequate.

The health and environmental risks of poor air quality are well understood in Defra and parts of DH/HPA but less well so elsewhere.

The delivery chain for achieving good air quality is wholly inadequate and pitifully resourced. It is also fragmented and the responsibility of many arms and agencies of central and local government, not all of which are playing their proper part in the process.

The primary means of improving air quality in England is to address emissions from road traffic. Although improvements in vehicle technology will play a part in this, the IAQM believes that much needs to done to understand the science of air pollution more fully and that the air quality objectives will only be achieved and maintained by influencing the behaviour of individuals and reducing the need for the use of the private car.


1. There is an extensive programme of air quality monitoring in the UK. In part this is the national Automated Urban and Rural Network (AURN) and in part it is regional and local networks operated by local authorities and other bodies. Although there are some arguments about just how well the data from these activities reflect the exposure of the public it is fair to say that there is only limited scope for improvement in this area.


2. The UK also makes considerable use of air quality modelling to provide estimates of air quality in areas where monitoring is not carried out. Although the absolute reliability of such modelling has been questioned, there is no evidence to suggest that the procedures are poorly executed.


3. The health and other environmental risks associated with poor air quality have been clearly identified by bodies such as the Committee on the Medical Effects of Air Pollution (COMEAP) and these have been acknowledged in those parts of Defra and DH/HPA with responsibilities for these matters. It must be realised, however, that this only represents current knowledge. Although much work has been done in this field in recent years there are still many questions that remain to be answered. What is clear, as the recent COMEAP report (Long-Term Exposure to Air Pollution: Effect on Mortality) states, is that a large number of deaths every year are advanced by the effects of air pollution and in particular by very fine particulate matter. There is still much debate over which specific element(s) of this are responsible for advancing deaths but the evidence is strong that particles are the main pollutant to address. There is also an acceptance in these bodies that road traffic is the predominant, although not the only, cause of air quality problems. This is especially the case in London but it is also a major factor in most other towns and cities in the UK.


4. It is much more questionable whether these risks are understood in other parts of Government. One difficulty in this is that Climate Change (CC) has dominated the "pollution agenda" in recent years with the consequence that measures have been introduced to address CC which have had adverse effects on air quality. One specific measure in this respect has been the encouragement of increased use of diesel vehicles. These do emit lower amounts of carbon dioxide but also emit greater quantities of particles and nitrogen dioxide, the main pollutant of concern (see also Para. 16).


5. The delivery chain for improving air quality is, at best, fragmented and often non-existent. There is a view held in some quarters that technological measures being introduced, especially in the road transport field, will deliver all the improvements that are needed. The evidence from monitoring shows that, following an improvement in air quality in the 1990s following the initial introduction of catalytic converters, there has been little further improvement in spite of supposed improved vehicle technology. It is worth noting that the largest step change in overall air quality was in 1992 with the introduction of the three-way catalytic converter. In particular this brought about improvements in carbon monoxide and total oxides of nitrogen. In contrast the effects on nitrogen dioxide concentrations were minimal. This is usually attributed to the fact that increases in the numbers of vehicles on the roads has swamped any benefits that may accrue from the technological improvements.


6. A further difficulty is the need for balancing approaches. Reference has already been made to the dominance CC issues have gained on the pollution agenda. There is a clear need for such global issues and, generally, local issues such as air quality to be treated in conjunction so that measures to address one do not have an adverse effect on the other and, where possible, have mutually beneficial effects.


7. Another issue of balance is that between national and local measures. National measures tend to be broad brush and, assuming they are effective, will produce overall benefits. There are, however, many cases where air quality problems arise as a consequence of local problems which are not amenable to control by national measures. Defra has recognised this in the early drafts of its submission to the EU for an extension in meeting the Limit Value for nitrogen dioxide by identifying areas where different types of traffic sources are responsible for air quality problems.


8. A major stumbling block to delivering improved air quality is a lack of co-ordination between the various parties involved in the process. This problem exists at both national and local level. In the national case, as has already been stated, Defra and DH/HPA have at least some understanding although this may not spread across the entire Departments. On the other hand there are other Government Departments; DfT, CLG, DECC and HMT for example, where there appears to be at best very limited awareness of air quality issues and, often, a total lack of understanding that air quality is still a major problem in terms of its health impacts and its wider environmental impacts. It is actually imperative that these Departments are involved in the Air Quality Management (AQM) process as each has an important part to play. Equally, although other Government Departments may not have quite the same direct involvement in AQM as these, they do have the potential to assist in delivering improved air quality by managing their own emissions.


9. DfT must be more closely engaged as traffic, and in particular road traffic, is the main cause of air quality problems in much of the UK. CLG has a major role in the planning process in particular and in local government in general. DECC must be involved to ensure a harmonisation of AQM and CC policies and HMT has an essential role in providing funding.


10. At a local level it is essential that similar links are established and maintained between the air quality professionals and the transport planners, climate change officers and development control planners. Although there are some local authorities where such links do exist there are many where they do not. There does not appear to be any consistent link between whether such relationships exist or not and whether an area has one or two tiers of administration. There are examples of good links where the highways functions are at a county council level and air quality is a district council function and of poor links where both functions are exercised in unitary authorities and vice versa.


11. There is another issue that is important at the local level. This is the question of Local Transport Plans (LTPs). There are a number of points that must be addressed here. First, in the current round of LTPs (LTP2) air quality was cited as one of the four key shared priorities with tackling congestion, improving road safety and improving accessibility. In spite of this research (Dotun Olowoporoku, University of the West of England, PhD thesis in preparation) shows that in many cases air quality has been treated as the fourth in order of priority. This is largely due to the requirement for the preparation of Joint LTPs by groups of local authorities of which maybe only one or two have Air Quality Management Areas.


12. The draft guidance for the next round of LTPs (LTP3) is likely to exacerbate this problem as air quality has been given a lower priority than was the case in LTP2. Given that when it was specifically listed as one of four, presumably equal, priorities air quality was nonetheless downgraded by many local authority Transport Planners it is unlikely that with the proposed LTP3 guidance the same Transport Planners will accord it the priority it needs.


13. The main problem in managing air quality is that the resources available are wholly inadequate. There is an apparent lack of proportion in the allocation of funds for various initiatives. This can be best illustrated by comparing the funding for various road safety measures and that for air quality work and the health impacts of road accidents and air quality. In the case of road safety there are numerous high profile campaigns, in particular the regular drink-driving campaigns, and many cases of extensive traffic management schemes, some of which may result in deterioration in local air quality. These measures are targeted at an annual death toll of approximately 3,000. In contrast, poor air quality which is believed to be responsible for at least 24,000 deaths advanced per year only attracts general attention when there is a major episode such as the London smog of 1952. Episodes such as this are, fortunately, rare and no subsequent episode has had the same impact. An episode in London in December 1991 was analysed in detail in a report for DoH (Anderson et al, 1995) which concluded that between 100 and 180 deaths during and after the episode could be attributed to air pollution. In July and August 2003 there were increases in deaths over and above what would have been expected. Many of these were attributed to the high temperatures experienced at the time but an analysis (Stedman JR, 2004) estimated that between 423 and 769 of the 2,045 "additional" deaths between 8 and 13 August were due to poor air quality; specifically particles and ozone. The range in this case is due to uncertainty in the magnitude of the effects of ozone.


14. It is, of course, necessary to strike a balance on this issue. It is appreciated that in a reasonably large proportion of, but not necessarily all, road traffic accidents the number of years of life lost by individual casualties will be greater than that lost by many individual victims of air pollution. It is, however, also necessary to consider the total loss of life years. The current estimate on this is an average of eight months per person per year which, based on a population of 60,000,000, equates to 40,000,000 years of life lost per year. In contrast, even allowing for a loss of 50 years of life per casualty in road traffic accidents, these equate to 150,000 years of life lost per year.


15. It is recognised that achieving improved air quality is not going to be an easy task. Part of the difficulty is that it is never going to be a simple task to quantify the outcomes of proposed measures in advance of their introduction. There is a need for more rigorous scientific research into air pollution. Although we do know far more now than was the case in 1952, there are still many questions that are unanswered.


16. Two major issues concern the two pollutants of greatest concern for LAQM: nitrogen dioxide and particulate matter. In the former case we have seen a marked reduction in the concentrations of total oxides of nitrogen (nitrogen dioxide + nitric oxide) but this is almost entirely due to reduced concentrations of nitric oxide. The Air Quality Expert Group (AQEG) produced a report (December 2007) on this which does identify some possible causes but also highlights a number of areas for further work. More recent work (Carslaw, 2009) suggests that increased concentrations of nitrogen dioxide that have been observed, particularly at roadside sites, are due to increased emissions of primary nitrogen dioxide from diesel-engine cars.


17. In the case of particles, there is still uncertainty as to whether particle mass is the most important metric and, if so, which size fraction, or whether particle numbers or surface area are the critical issue. There are also key questions on source attribution for particles and on whether different size fractions may have different health impacts. One school of thought suggests that the finer fractions may be most important in chronic effects, and in particular with advancing mortality, whereas the coarser particles may be responsible for acute effects such as triggering asthmatic attacks.


18. Although, as has been stated, it is difficult to be precise in identifying the outcomes of measures introduced to improve air quality, the current financial situation does present one opportunity in this respect. It is generally accepted that the majority of air quality problems in the UK arise from emissions from road traffic. There have been a number of reports that road traffic has reduced due to the financial crisis and this potentially presents us with an effective intervention study into the outcomes of reducing the amount of road traffic in the UK. Attempts to do so have been made in the past with short term events such as the fuel delivery problems in 2000. These events, however, were too short for any meaningful conclusions to be drawn as normal variations in air pollutant concentrations swamped any other effects.


19. Even if this opportunity does produce evidence on the amount of reduction in road traffic necessary to meet the EU Limit Values for air pollution there still remains the problem of achieving those reductions in the long term. This will require a major change in the mindset of the general population and, in particular, amongst users of the private car. It is certain that there will be a need for the use of innovative means of transport and for better, more flexible public transport to meet the needs of the travelling public. There is also the need for other measures to reduce the need for travel. There are current examples such as increased home working but these are often offset by the lack of local facilities which encourage people to use their cars to travel to out-of-town shopping centres.


20. This submission has concentrated on those issues that are associated with the Local Air Quality Management process in the UK. There are also air quality issues that lie almost wholly within the remit of Her Majesty's Government, although measures taken to improve local air quality will assist in achieving targets in these matters. One of these of concern both in relation to human health and to eco-systems is the steady increase in concentrations of background, tropospheric ozone. Others are a widespread problem with the deposition of nutrient nitrogen on sensitive habitats and a residual problem of acid deposition.




Anderson HR., Limb ES., Bland JM., de Leon AP., Strachan DP., Bower JS., 1995. The health effects of an air pollution episode in London December 1991. St. George's Hospital Medical School/UK Department of Health, London.

Stedman J R, Atmospheric Environment, Volume 38, Issue 8, March 2004, Pages 1087-1090.

Air Quality Expert Group report - Trends in primary nitrogen dioxide in the UK, Defra, December 2007.

Carslaw D, Latest Evidence and Future Prospects for Primary NO2 Emissions, Nitrogen Dioxide - Time for Compliance, November 2009.




1 December 2009