Written evidence submitted by John Bryson, Francis Pope, Catherine Muller, Zongbo Shi, Suzanne Bartington, Lee Chapman, Omid Ghaffarpasand, Roy Harrison and William Bloss (AQU0032)


This submission had been written and compiled by the West Midlands Air Quality Improvement Programme. WM-Air is a NERC funded initiative, led by the University of Birmingham, working in collaboration with over 20 cross sector partners, to apply environmental science expertise to support the improvement of air quality, and associated health, environmental and economic benefits, across the West Midlands. The WM-Air team draws on the University of Birmingham’s internationally leading research expertise in air pollution science and its health and economic impacts. The focus is on the identification of solutions that will transform air quality by developing new approaches to measuring air pollution sources and levels, new tools to predict air quality and associated health and economic impacts and new awareness and capability that will lead to new regional policy measures and solutions.


  1. Did the UK Government’s 2019 Air Quality Strategy set out an effective and deliverable strategy to tackle the UK’s poor air quality and address the issues raised in our 2018 report? Has the UK Government put in place the necessary structures and resources to deliver its strategy?  


Greater focus has been placed in the Air Quality Strategy to protect human and environmental health. Nevertheless, the overall strategy still lacks a core health equity focus, given the known relationships between poor air quality, deprivation, and adverse health outcomes. Specifically, the relatively narrow focus on NO2 by local authorities urgently needs to shift to a broader range of pollutants, considering the health geography of affected populations. Specifically, particulate matter (PM) should be investigated, including improvements in monitoring capabilities. Indoor air quality is still largely overlooked (although of increasing concern amongst the wider public) with the focus upon ambient pollutant levels. The importance of limiting indoor air pollutants is critical in a number of settings including educational and health care. This becomes even more critical when the links between COVID-19 and household related air quality issues are considered.[1]


Delivery will be exceptionally challenging for local authorities which face significant financial deficits following COVID-19, which are estimated at £11Bn in June 2020,[2] which is likely to lead to widespread restructuring and radical budget savings across local Government. This may support improved structures integrated Local Air Quality Management strategy delivery and input from a wider range of local partners; recognised to be currently challenging within two-tier authorities. Enhanced powers and resources will be essential to achieve effective delivery of the strategy and this notably includes working collaboratively across administrative boundaries.


Some effective strategies are proposed in the Air Quality Strategy to tackle poor air quality. However, there are missing elements in this strategy that will have a major impact on this country’s ability to improve air quality in the future, including a limited ability to understand the sources and processes controlling secondary pollutants, particularly PM2.5 and ozone. As a result, the UK’s ability to develop the most effective mitigation measures are currently impaired.


a)      A large fraction of pollutants is derived from the regional background, including the European continent. Therefore national and international coordination is a key aspect in tackling air pollution. This means, for example, that solutions to enhancing air quality in the West Midlands require interventions that are outside any influence or control of the West Midlands Combined Authority. Thus, solutions need to be identified to address the different scales at which pollution is created – from the regional, national and international. The UK must engage with EU countries to address air pollution. It is noted, that in certain geographic locations, PM2.5 increased rather than decreased during the COVID-19 lockdown. This is in part due to the long-range transport of air pollution from the continent.


b)     The Clean Air Strategic Partnership Fund has provided support for enhancing the UK’s ability to understand air pollution and to predict air quality. But a long-term strategy to further support the development of air quality observation and prediction capability is needed.


c)      It is critical that an appropriate set of monitoring stations are established to provide regional background readings of air pollution for the core population centres. Currently, the background network is too sparse to be effective.


d)     NO2 is the key pollutant targeted by Clean Air Zones (CAZs) and is the government’s current priority. CAZs do not necessarily improve overall air quality, which needs to consider air pollutants other than NO2. Furthermore, poorly implemented CAZs have the potential to only displace sources of air pollution rather than remove them.


e)      Monitoring capability of PM2.5 and PM10 are too limited, especially outside London. Chemical speciation of PM2.5 is even more limited. This has a major impact on the UK’s ability to validate models and to predict future PM pollution. Low cost monitoring may provide part of the solution to greater monitoring capacity and capability, but calibratory and quality assurance issues must be well understood for this approach to be effective.[3] [4]


In terms of action plans that are designed to mitigate the transportation sector’s contribution to local and national emission inventories, it seems that the strategies have been developed properly and could notably improve UK air quality.


It is important that CAZs are introduced where they are required and as soon as is possible. Every CAZ should be monitored to avoid any impacts related to plan continuation bias. Thus, monitoring must be related to on-going diagnostics to ensure that interventions are identified to prevent any air pollution displacement associated with the introduction of a CAZ. This monitoring should include an agile approach to policy implementation that includes rapid local adjustments to the CAZ boundary/geography. The key must be the development of a CAZ geography that minimize overall population exposure to air pollution.


  1. Will the Environment Bill provide England with a robust legal framework to define and enforce air quality limits? 


The Environmental Bill will have positive impacts on the transportation sector. It could accelerate fleet refurbishment and even encourage the shift toward cleaner fuels and towards carbon-free/low-emission transportation.[5] However, the Environmental Bill should be designed to balance reductions in fleet emissions with socio-economic benefits.


There are clear gaps and potential legal loopholes with regard to enforcement of smoke control zones and sales of approved stoves/solid fuels. Resources within local authorities are likely to be a limiting factor in relationship to effective legal enforcement.


There are some interesting loopholes. For example, 150,000 HGV journeys per year are made in the UK along the UK-Ireland landbridge. This route is of critical importance for Ireland; 40% of Ireland’s unitised exports to the EU continent are transported via the UK landbridge with an estimated value of €18.2 billion. This represents a third country’s contribution to UK air pollution and, more importantly, the Irish HGV fleet is quite a lot older compared to the UK fleet and thus creates more pollution. The UK should be concerned with the number of HGV journeys along the landbridge. There should be a strategy in place to ensure that the landbridge is only accessible to low-emission HGVs. Similar considerations should be undertaken for mainland Europe HGVs.


  1. What progress had the UK Government made on reducing air pollution and enforcing legal pollution limits before the Covid-19 pandemic?


Broadly levels of UK air pollutants have decreased in recent decades, although the decline in PM concentrations has plateaued in recent years.


Air quality management at a local level has been a policy failure, with repeated breaches of air quality limits (e.g. annual NO2) including in those areas outside the Clean Air Zone cities remit. This failure is not just in the large cities as there are breaches in smaller towns and cities that also need to be addressed. The lack of joined up thinking between the carbon benefits of diesel vehicles and air pollution disadvantages of diesel vehicles is a clear example of where too little analysis was performed on the wider implications of a policy decision (to encourage dieselification of the fleet).


A key weakness is that the UK has yet to adopt an integrated approach to reducing air pollution. Such an approach must be based on ensuring that all strategies, policies, and regulations are developed to enhance air quality[6]. Thus, the problem with air quality policy is that it tends to sideline the problem within a designated air quality policy and related policy infrastructure. This isolates air quality from the primary policy areas that play a critical role in contributing to air quality. Every policy should be both air quality and climate change compliant or, the worst-case scenario should be that a policy intervention should be air quality and climate change neutral in its impacts.


Achieving an improved understanding of the unintended consequences of public policy decisions across Govt departments and taking actions to mitigate these at a policy formulation stage could mitigate such conflicts and impacts in future years. Analyses of core Government strategies (e.g. Industrial Strategy, Clean Growth Strategy, 25-Year Environment Plan, NHS Long Term Plan) undertaken within the Clean Air SPF ANTICIPATE study identified a broad range of emerging policies with potentially negative impacts upon ambient air quality.[7]


  1. What does the early evidence from the COVID-19 pandemic say about the impact of poor air quality on health, and health inequalities for disadvantaged communities and other at-risk groups, and possible policy responses?


The COVID-19 lockdowns has caused a rapid decrease in NO2 in many locations because of the reductions in traffic emissions. Similar reductions in PM have not been observed because of the more regional nature of this pollutant type. The reductions in NO2 has potential health benefits to the whole population, and in particular to those with high susceptibility: the young, the old and those with pre-existing medical conditions exacerbated by air pollution e.g. asthma and COPD.


The relationship between air pollution, health inequity and COVID-19 morbidity/mortality is likely to be highly confounded by socio-demographic factors, including income deprivation, gender, ethnicity, household structure, housing characteristics, lifestyle and behavioural and health access factors. However, it is recognized that specific pollutants are respiratory mucosal irritants and long-term exposure to NO2/PM2.5 increases the risk of a range of chronic health conditions, known to be associated with poor outcomes from COVID-19 infection. Further research is required to fully understand these relationships, including ongoing research undertaken in partnership between the University of Birmingham and University Hopsitals Birmingham NHS Foundation Trust.[8]


Specifically, impacts of indoor air pollution exposure, relationships with pre-existing conditions and factors related to health-seeking behaviours require further investigation, utilizing robust observational studies (e.g. case-control, cohorts) rather than reliance upon ecological/cross-sectional studies. Anecdotally, the ratio of time spent indoors and outdoors is highly dependent on housing provision. For example, under lockdown conditions, it was much easier for those with gardens to exercise outside for longer than the allowed one hour per day.  The provision of green space in the towns and cities of the UK vary widely from location to location, which likely affected the ability to exercise. Hence there are clear links between the public health issues of air pollution, exercise, obesity and physical inactivity.

  1. What are the current and emerging risks and opportunities for air quality posed by:

a) Short-term policy and societal changes in response to the pandemic, for example changes to transport to reduce the risk of transmission, and; b) Medium and long-term actions to promote economic recovery.


There is little change in PM2.5 concentrations that can be attributed to the lockdown, illustrating the potential challenge for policy-making to meet the legal limit. There is insufficient modelling and scientific capability to predict what policy action(s) will be sufficient to bring down PM2.5 levels and meet the Air Quality Strategy goals.


The response of air pollution to COVID-19 lockdowns provided a unique opportunity to understand the adequacy and inadequacy of potential mitigation actions in protecting public health.[9] For example, while significant reductions in mobility led to a decrease in NO2 concentrations, the degree of change is not as large as the mobility data identified: 60-80% decrease in traffic volumes but only ~20% decrease in NO2 concentrations in London based on the urban background sites. The mobility decrease did not result in a decrease in PM2.5. Further research in required on PM2.5 to identify core intervention opportunities to limit emissions and secondary particle formation.


Working from home may increase in the future but the use of public transport will likely reduce in the short-term due to concerns with virus transmission; these have opposite effects on air pollutant emissions. Increased non-motorized transport options (walking and cycling) will be beneficial for air pollution. There is anecdotal evidence that cheap vehicles, with greater polluting ability, are being purchased to replace public transport options in some households.


Working from home will also have implications for heating based emissions, with heating individual households generally being more inefficient than office based solutions. The implications of heating based emissions will become more apparent as the colder months approach.


Increases in web-based shopping and reductions in the use of physical shops will have implications for transport and hence air pollution. It will likely reduce private vehicle usage but will much increase final mile deliveries for online deliveries. Emissions regulations on these final mile vehicle, which are typically diesel powered lights good vehicles (LGVs), could have a significant effect on air quality.


In the long-term, air pollution emissions from traffic will reduce. But it is likely that this is insufficient to tackle secondary pollution (PM2.5 and O3), as shown from the response of air quality to COVID-19.  For example, O3 at the roadside sites increased substantially due to the lockdown measures (reduced NO titration effect).


The following risks/opportunities linked to COVID-19 can be identified for the transportation sector:


  1. Major alterations to travel demand and travel capacity related to the shift to remote working with lifestyle implications for urban residents, but also implications for those not able to engage in remote working.
  2. The spatial distribution of energy demand and energy consumption altered and the impacts on emissions and air quality needs to be modelled.
  3. During lockdown there was a shift towards walking and bicycles, but with the easing of lockdown there has been a shift from public to private transport which contributes to air pollution. 
  4. Policy discussions are urgently required regarding the implications of COVID-19 on land use planning and on building design[10].


  1. What are the current and emerging risks and opportunities for air quality posed by: b) Medium and long-term actions to promote economic recovery.



-          Changes in lifestyle behaviour related to COVID-19 including increases in recreational levels of physical activity, which if sustained has the potential to improve physical and mental health and hence population wellbeing.

-          Major, radical changes in health service delivery. It is important to note that the NHS is responsible for approximately 5% of road traffic and has the potential to contribute to longer term improvements in ambient air quality in areas of high health service usage. NHS partners have noted positive benefits from delivering e-consultations for outpatient services and by restricting visitor access, reflecting recommendations made within the ANTICIPATE study.[11]

-          There is emerging evidence of lifestyle changes including smoking cessation during the lockdown period which may have longer term benefits for respiratory health services.

-          Major opportunity for active travel investment - including emergency active travel schemes and potential for redirection of leisure budgets towards active travel.

-          Reducing shipping/aviation activity.



-          Long-term health impacts due to delayed access to health care for those with chronic health conditions.

-          Rebound effects in relation to public transportation choices due to social distancing/reduced public transport capacity/public health messaging. These rebound effects will increase air pollution.

-          Poorer indoor air quality due to changes in time-activity patterns in indoor/outdoor environments

-          The distribution, disposal or incineration of PPE must be considered as a pollutant source.

-          Financial impacts on local authorities including the need to introduce emergency budget cuts. It is important that any alteration has a neutral or positive impact on air quality and its wider impacts.

-          Delays to progressing Environment Bill and legal delivery framework.  



[3] Crilley, L.R., A. Singh, L.J. Kramer, M.D. Shaw, M.S. Alam, J.S. Apte, W.J. Bloss, L.H. Ruiz, P. Fu, W. Fu, S. Gani, M. Gatari, E. Ilyinskaya, A.C. Lewis, D. Ng’ang’a, Y. Sun, R.C.W. Whitty, S. Yue, S. Young, and F.D. Pope (2020) ‘Effect of aerosol composition on the performance of low-cost optical particle correction factors’ Atmospheric Measurement Techniques, http://doi.org/10.5194/amt-2019-370

[4] Crilley, L., M. Shaw, R. Pound, L. J. Kramer, R. Price, S. Young, A. C. Lewis and F. D. Pope (2018) ‘Evaluation of a low-cost optical particle counter (Alphasense OPC-N2) for ambient air monitoring’ Atmospheric Measurement Techniques, 11, 709-720. http://dx.doi.org/10.5194/amt-2017-308.

[5] Ghaffarpasand, O., D.C.S. Beddows, K. Ropkins and F.D. Pope (2020) ‘Real-world assessment of vehicle air pollutant emissions subset by vehicle type, fuel and EURO class: New findings from the recent UK EDAR field campaigns, and implications for emissions restricted zones’ Science of the Total Environment, 734, 139416, https://doi.org/10.1016/j.scitotenv.2020.139416.

[6] Andres, L., Bakare, H.,  Bryson, J.R., Khaemba, W., Melgaço L. & Mwaniki G. (2019), ‘Planning, temporary urbanism and citizen-led alternative-substitute place-making in the Global South’, Regional Studies, DOI: 10.1080/00343404.2019.1665645

[7] Bartington, S., Moller, S., Hamilton, I., and Gilbert N. (2019) Summary of four UK government strategies.


[8] https://www.researchsquare.com/article/rs-35617/v1

[9] https://www.birmingham.ac.uk/news/latest/2020/07/air-and-noise-quality-study-oxford.aspx

[10] Andres, L., Bryson, J.R., Denoon-Stevens, S., Bakare, H., du Toit K. and Melgaço L., (2020), ’Viewpoint Calling for responsible inclusive planning and healthy cities in Africa’, Town Planning Review,  https://doi.org/10.3828/tpr.

[11] Recommendations for mitigating air quality impacts associated with

the ‘NHS App’

Nigel Gilbert1, Suzanne Bartington2, Ian Hamilton3, Sarah Moller4, Kirstie Hatcher1, Emma Pearce5 and Valentine Seymour1. Policy Brief 2020