on this page
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Markets
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Services
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Location
London
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Client
DEFRA
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Collaborators
University of Birmingham
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Completion date
03/2026
Introduction
Providing the UK government with evidence to inform future policy on black carbon and ultrafine particles and improve air quality outcomes.
Defra commissioned AtkinsRéalis to strengthen the UK evidence base on black carbon and ultrafine particles, two pollutants not specifically regulated in the UK. Limited monitoring data alongside a rapidly evolving research base created uncertainty around their health and environmental impacts.
AtkinsRéalis conducted reviews to better understand emerging UK and international requirements, including updates to the UNECE Gothenburg Protocol and the EU Ambient Air Quality Directive. This enables more informed, proportionate decision-making to protect public health and improve air quality.
Please note that you are now leaving the AtkinsRéalis website (legal name: AtkinsRéalis Group inc.) and entering a website maintained by a third party (the "External Website") and that you do so at your own risk.
AtkinsRéalis has no control over the External Website, any data or other content contained therein or any additional linked websites. The link to the External Website is provided for convenience purposes only. By clicking "Accept" you acknowledge and agree that AtkinsRéalis is not responsible, and does not accept or assume any responsibility or liability whatsoever for the data protection policy, the content, the data or the technical operation of the External Website and/or any linked websites and that AtkinsRéalis is not liable for the terms and conditions (or terms of use) of the External Website. Further, you acknowledge and agree that you assume all risks resulting from entering and/or using the External Website and/or any linked websites.
BY ENTERING THE EXTERNAL WEBSITE, YOU ALSO ACKNOWLEDGE AND AGREE THAT YOU COMPLETELY AND IRREVOCABLY WAIVE ANY AND ALL RIGHTS AND CLAIMS AGAINST ATKINSRÉALIS, AND RELEASE, DISCHARGE, INDEMNIFY AND HOLD HARMLESS ATKINSRÉALIS, ITS OFFICERS, EMPLOYEES, DIRECTORS AND AGENTS FROM ANY AND ALL LIABILITY INCLUDING BUT NOT LIMITED TO LIABILITY FOR LOSS, DAMAGES, EXPENSES AND COSTS ARISING OUT OF OR IN CONNECTION WITH ENTERING AND/OR USING THE EXTERNAL WEBSITE AND/OR ANY LINKED WEBSITES AND ANY DATA AND/OR CONTENT CONTAINED THEREIN.
Such waiver and release specifically includes, without limitation, any and all rights and claims pertaining to reliance on the data or content of the External Website, or claims pertaining to the processing of personal data, including but not limited to any rights under any applicable data protection statute. You also recognize by clicking “Accept” that the terms of this disclaimer are reasonable.
The information provided by Virtua Research cited herein is provided “as is” and “as available” without warranty of any kind. Use of any Virtua Research data is at a user’s own risk and Virtua Research disclaims any liability for use of the Virtua Research data. Although the information is obtained or compiled from reliable sources Virtua Research neither can nor does guarantee or make any representation or warranty, either express or implied, as to the accuracy, validity, sequence, timeliness, completeness or continued availability of any information or data, including third-party content, made available herein. In no event shall Virtua Research be liable for any decision made or action or inaction taken in reliance on any information or data, including third-party content. Virtua Research further explicitly disclaims, to the fullest extent permitted by applicable law, any warranty of any kind, whether express or implied, including warranties of merchantability, fitness for a particular purpose and non-infringement.
The consensus estimate provided by Virtua Research is based on estimates, forecasts and predictions made by third party financial analysts, as described above. It is not prepared based on information provided by AtkinsRéalis and can only be seen as a consensus view on AtkinsRéalis' possible future results from an outside perspective. AtkinsRéalis has not provided input on these forecasts, except by referring to past publicly disclosed information. AtkinsRéalis does not accept any responsibility for the quality or accuracy of any individual or average of forecasts or estimates. This web page contains forward-looking statements based on current assumptions and forecasts made by third parties. Various known and unknown risks, uncertainties and other factors could lead to material differences between AtkinsRéalis' actual future results, financial situation, development or performance, and the estimates given here.
The Challenge
Defra required a clear, evidence‑based understanding of black carbon and ultrafine particles to support future policy decisions. Neither pollutant is currently subject to specific UK regulation, and available monitoring data and emissions estimates are limited.
At the same time, international policy is evolving. Proposed updates to the UNECE Convention on Long‑Range Transboundary Air Pollution (CLRTAP) may introduce new requirements for black carbon, while the revised EU Ambient Air Quality Directive mandates ultrafine particle monitoring from 2027.
This created an urgent need to consolidate complex and fragmented evidence into a usable, policy‑ready foundation.
Please note that you are now leaving the AtkinsRéalis website (legal name: AtkinsRéalis Group inc.) and entering a website maintained by a third party (the "External Website") and that you do so at your own risk.
AtkinsRéalis has no control over the External Website, any data or other content contained therein or any additional linked websites. The link to the External Website is provided for convenience purposes only. By clicking "Accept" you acknowledge and agree that AtkinsRéalis is not responsible, and does not accept or assume any responsibility or liability whatsoever for the data protection policy, the content, the data or the technical operation of the External Website and/or any linked websites and that AtkinsRéalis is not liable for the terms and conditions (or terms of use) of the External Website. Further, you acknowledge and agree that you assume all risks resulting from entering and/or using the External Website and/or any linked websites.
BY ENTERING THE EXTERNAL WEBSITE, YOU ALSO ACKNOWLEDGE AND AGREE THAT YOU COMPLETELY AND IRREVOCABLY WAIVE ANY AND ALL RIGHTS AND CLAIMS AGAINST ATKINSRÉALIS, AND RELEASE, DISCHARGE, INDEMNIFY AND HOLD HARMLESS ATKINSRÉALIS, ITS OFFICERS, EMPLOYEES, DIRECTORS AND AGENTS FROM ANY AND ALL LIABILITY INCLUDING BUT NOT LIMITED TO LIABILITY FOR LOSS, DAMAGES, EXPENSES AND COSTS ARISING OUT OF OR IN CONNECTION WITH ENTERING AND/OR USING THE EXTERNAL WEBSITE AND/OR ANY LINKED WEBSITES AND ANY DATA AND/OR CONTENT CONTAINED THEREIN.
Such waiver and release specifically includes, without limitation, any and all rights and claims pertaining to reliance on the data or content of the External Website, or claims pertaining to the processing of personal data, including but not limited to any rights under any applicable data protection statute. You also recognize by clicking “Accept” that the terms of this disclaimer are reasonable.
The information provided by Virtua Research cited herein is provided “as is” and “as available” without warranty of any kind. Use of any Virtua Research data is at a user’s own risk and Virtua Research disclaims any liability for use of the Virtua Research data. Although the information is obtained or compiled from reliable sources Virtua Research neither can nor does guarantee or make any representation or warranty, either express or implied, as to the accuracy, validity, sequence, timeliness, completeness or continued availability of any information or data, including third-party content, made available herein. In no event shall Virtua Research be liable for any decision made or action or inaction taken in reliance on any information or data, including third-party content. Virtua Research further explicitly disclaims, to the fullest extent permitted by applicable law, any warranty of any kind, whether express or implied, including warranties of merchantability, fitness for a particular purpose and non-infringement.
The consensus estimate provided by Virtua Research is based on estimates, forecasts and predictions made by third party financial analysts, as described above. It is not prepared based on information provided by AtkinsRéalis and can only be seen as a consensus view on AtkinsRéalis' possible future results from an outside perspective. AtkinsRéalis has not provided input on these forecasts, except by referring to past publicly disclosed information. AtkinsRéalis does not accept any responsibility for the quality or accuracy of any individual or average of forecasts or estimates. This web page contains forward-looking statements based on current assumptions and forecasts made by third parties. Various known and unknown risks, uncertainties and other factors could lead to material differences between AtkinsRéalis' actual future results, financial situation, development or performance, and the estimates given here.
Our Role
AtkinsRéalis led structured literature reviews in collaboration with the University of Birmingham, combining consultancy and academic expertise to ensure robust and independent analysis.
Key contributions include:
- Synthesised over 1,000 research papers and more than 300 references
- Reviewed global approaches to monitoring, regulation and control
- Engaged international stakeholders, including the World Health Organization and European regulators
- Assessed sources, measurement methods, health impacts and policy gaps
Our work focused on translating complex scientific evidence into clear, actionable insight to support government decision‑making.
Please note that you are now leaving the AtkinsRéalis website (legal name: AtkinsRéalis Group inc.) and entering a website maintained by a third party (the "External Website") and that you do so at your own risk.
AtkinsRéalis has no control over the External Website, any data or other content contained therein or any additional linked websites. The link to the External Website is provided for convenience purposes only. By clicking "Accept" you acknowledge and agree that AtkinsRéalis is not responsible, and does not accept or assume any responsibility or liability whatsoever for the data protection policy, the content, the data or the technical operation of the External Website and/or any linked websites and that AtkinsRéalis is not liable for the terms and conditions (or terms of use) of the External Website. Further, you acknowledge and agree that you assume all risks resulting from entering and/or using the External Website and/or any linked websites.
BY ENTERING THE EXTERNAL WEBSITE, YOU ALSO ACKNOWLEDGE AND AGREE THAT YOU COMPLETELY AND IRREVOCABLY WAIVE ANY AND ALL RIGHTS AND CLAIMS AGAINST ATKINSRÉALIS, AND RELEASE, DISCHARGE, INDEMNIFY AND HOLD HARMLESS ATKINSRÉALIS, ITS OFFICERS, EMPLOYEES, DIRECTORS AND AGENTS FROM ANY AND ALL LIABILITY INCLUDING BUT NOT LIMITED TO LIABILITY FOR LOSS, DAMAGES, EXPENSES AND COSTS ARISING OUT OF OR IN CONNECTION WITH ENTERING AND/OR USING THE EXTERNAL WEBSITE AND/OR ANY LINKED WEBSITES AND ANY DATA AND/OR CONTENT CONTAINED THEREIN.
Such waiver and release specifically includes, without limitation, any and all rights and claims pertaining to reliance on the data or content of the External Website, or claims pertaining to the processing of personal data, including but not limited to any rights under any applicable data protection statute. You also recognize by clicking “Accept” that the terms of this disclaimer are reasonable.
The information provided by Virtua Research cited herein is provided “as is” and “as available” without warranty of any kind. Use of any Virtua Research data is at a user’s own risk and Virtua Research disclaims any liability for use of the Virtua Research data. Although the information is obtained or compiled from reliable sources Virtua Research neither can nor does guarantee or make any representation or warranty, either express or implied, as to the accuracy, validity, sequence, timeliness, completeness or continued availability of any information or data, including third-party content, made available herein. In no event shall Virtua Research be liable for any decision made or action or inaction taken in reliance on any information or data, including third-party content. Virtua Research further explicitly disclaims, to the fullest extent permitted by applicable law, any warranty of any kind, whether express or implied, including warranties of merchantability, fitness for a particular purpose and non-infringement.
The consensus estimate provided by Virtua Research is based on estimates, forecasts and predictions made by third party financial analysts, as described above. It is not prepared based on information provided by AtkinsRéalis and can only be seen as a consensus view on AtkinsRéalis' possible future results from an outside perspective. AtkinsRéalis has not provided input on these forecasts, except by referring to past publicly disclosed information. AtkinsRéalis does not accept any responsibility for the quality or accuracy of any individual or average of forecasts or estimates. This web page contains forward-looking statements based on current assumptions and forecasts made by third parties. Various known and unknown risks, uncertainties and other factors could lead to material differences between AtkinsRéalis' actual future results, financial situation, development or performance, and the estimates given here.
The Impact
The outcomes provided Defra with a clearer, evidence‑based foundation for future air quality policy.
They:
- Identify priority actions for monitoring and data improvement
- Highlight gaps in understanding of exposure and health impacts
- Support more consistent measurement and emissions reporting
- Inform integration of black carbon and ultrafine particles into climate and air quality policy
By strengthening the evidence base, the work enables proportionate, timely and effective policy responses that will help improve air quality, protect public health and support long‑term environmental outcomes.
Please note that you are now leaving the AtkinsRéalis website (legal name: AtkinsRéalis Group inc.) and entering a website maintained by a third party (the "External Website") and that you do so at your own risk.
AtkinsRéalis has no control over the External Website, any data or other content contained therein or any additional linked websites. The link to the External Website is provided for convenience purposes only. By clicking "Accept" you acknowledge and agree that AtkinsRéalis is not responsible, and does not accept or assume any responsibility or liability whatsoever for the data protection policy, the content, the data or the technical operation of the External Website and/or any linked websites and that AtkinsRéalis is not liable for the terms and conditions (or terms of use) of the External Website. Further, you acknowledge and agree that you assume all risks resulting from entering and/or using the External Website and/or any linked websites.
BY ENTERING THE EXTERNAL WEBSITE, YOU ALSO ACKNOWLEDGE AND AGREE THAT YOU COMPLETELY AND IRREVOCABLY WAIVE ANY AND ALL RIGHTS AND CLAIMS AGAINST ATKINSRÉALIS, AND RELEASE, DISCHARGE, INDEMNIFY AND HOLD HARMLESS ATKINSRÉALIS, ITS OFFICERS, EMPLOYEES, DIRECTORS AND AGENTS FROM ANY AND ALL LIABILITY INCLUDING BUT NOT LIMITED TO LIABILITY FOR LOSS, DAMAGES, EXPENSES AND COSTS ARISING OUT OF OR IN CONNECTION WITH ENTERING AND/OR USING THE EXTERNAL WEBSITE AND/OR ANY LINKED WEBSITES AND ANY DATA AND/OR CONTENT CONTAINED THEREIN.
Such waiver and release specifically includes, without limitation, any and all rights and claims pertaining to reliance on the data or content of the External Website, or claims pertaining to the processing of personal data, including but not limited to any rights under any applicable data protection statute. You also recognize by clicking “Accept” that the terms of this disclaimer are reasonable.
The information provided by Virtua Research cited herein is provided “as is” and “as available” without warranty of any kind. Use of any Virtua Research data is at a user’s own risk and Virtua Research disclaims any liability for use of the Virtua Research data. Although the information is obtained or compiled from reliable sources Virtua Research neither can nor does guarantee or make any representation or warranty, either express or implied, as to the accuracy, validity, sequence, timeliness, completeness or continued availability of any information or data, including third-party content, made available herein. In no event shall Virtua Research be liable for any decision made or action or inaction taken in reliance on any information or data, including third-party content. Virtua Research further explicitly disclaims, to the fullest extent permitted by applicable law, any warranty of any kind, whether express or implied, including warranties of merchantability, fitness for a particular purpose and non-infringement.
The consensus estimate provided by Virtua Research is based on estimates, forecasts and predictions made by third party financial analysts, as described above. It is not prepared based on information provided by AtkinsRéalis and can only be seen as a consensus view on AtkinsRéalis' possible future results from an outside perspective. AtkinsRéalis has not provided input on these forecasts, except by referring to past publicly disclosed information. AtkinsRéalis does not accept any responsibility for the quality or accuracy of any individual or average of forecasts or estimates. This web page contains forward-looking statements based on current assumptions and forecasts made by third parties. Various known and unknown risks, uncertainties and other factors could lead to material differences between AtkinsRéalis' actual future results, financial situation, development or performance, and the estimates given here.
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