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Cambridge Institute for Sustainability Leadership (CISL)


Gabriel is an active research expert in human exposure science with specific interests in addressing air pollution in rapidly urbanising cities in Africa and other LMICs through a) increasing awareness on the effects of air pollution and climate change on human health and the environment, b) increasing access and capacity to interpret air quality data, c) integrating this air pollution evidence into policy and practice and d) simplifying existing information related to air quality interventions – including related co-benefits and unintended consequences to make it easier for decision makers to anticipate the measures available to improve air quality.

Gabriel has a broad air pollution assessment and epidemiology background, with specific training and expertise in air pollution monitoring and modelling to understand exposure, using exposure feedback as an intervention, integrating evidence to policy and practice, and applying collaborative interdisciplinary research approaches to co-design interventions. Gabriel is passionate about promoting context-specific evidence informed and citizen science led approaches to tackle air pollution, climate change and always eager to learn and apply different societal nuances to design interventions.

Gabriel’s research approach is centred on interdisciplinary, collaborative, and participatory involvement of actors within and outside academia (community, commercial and policy) into the co-production and co-design of context-specific evidence informed strategies to address air pollution in urban settings in Africa and other LMICs. He currently works with actors in policy, business, academia, international development in various countries in Africa, the UK, Europe, Asia and the U.S.



Gabriel’s current research interests focus on the interconnectivity between environmental health and disease with a view to helping foster healthier and safer communities. Gabriel has a wider ambition to raise public awareness of air pollution exposure and engage stakeholders across African cities to address the air pollution problem using evidence informed policies and programmes. Gabriel is also interested in increasing capacity and integrate air pollution data in healthcare, policy and practice and increasing air pollution, climate change and health awareness. His approach is centred on collaborative participatory involvement of actors within and outside academia (community, commercial and policy) into the co-production and co-design of context specific interventions to address non-communicable disease risk by focusing on air pollution in rapidly urbanising settings.


  • 2020 to 2023: Prince of Wales Global Sustainability Fellow
  • 2019 to 2020: Founder, African Centre for Clean Air
  • 2015 to 2019: Postgraduate researcher, University of Aberdeen, Respiratory Group
  • 2013 to 2018: Operations Director, Green Heat Uganda
  • 2011 to 2013: Master’s student, Northeast Normal University
  • 2010 to 2011: Quality Assurance Specialist, Nile Breweries Limited


  • PhD Medical Sciences, University of Aberdeen
  • Pan African Thoracic Society Methods in Epidemiology Clinical and Research Operations Research (PATS MECOR Level 2), Liverpool School of Tropical Medicine
  • M.Sc. Organic Chemistry, Northeast Normal University
  • BSc Food Processing Technology; Kyambogo University

Other affiliations

  • 2021 to date: Honorary Visiting Fellow, MRC Epidemiology Unit, University of Cambridge
  • 2021 to date: Bye Fellow, Murray Edwards College, University of Cambridge
  • 2021 to date: Visiting Research Fellow, AirQo, Makerere University
  • Air Quality Faculty: Pan African Thoracic Society Methods in Epidemiology Clinical and Research Operations Research (PATS MECOR)
  • Biomass Reduction and Environmental Air Towards Health Effects (BREATHE) -Africa Partnership

Funding and awards

  • Air Quality and Non-communicable Diseases Fellowship Extension (PI) 2023
  • The National Research Council (NERC) Impact Grant: Discipline Hoping (DH) for Environmental Solutions Application (PI) 2021
  • Air Quality and Non-communicable Diseases Fellowship (PI) 2020
  • Systems of Cities: Urban Mobility in Kampala and its Surrounding Areas (PI)
  • Understanding Household Fuel Transitions: The Case of Namuwongo (Kampala). 2020. Collaboration study between ACCA, ACTogether, EASE Women’s enterprise and University of Birmingham (PI)
  • PATS MECOR Small grant. 2019. Determining the level of exposure to ambient air pollution among urban traffic-junction officers in Kampala, Uganda
  • BREATHE Small Awards 2018: Effect of cooking behaviour on exposure to household air pollution from different cooking fuels (PI)
  • Biomass Reduction and Environmental Air Towards Health Effects in Africa – BREATHE Partnership. MRC, UK. (Postgraduate Researcher)
  • UN Capital Development Fund (UNCDF) Clean Start.
  • Value addition in milk production using renewable energy. United States Africa Development Fund (Co-PI).


Key publications: 

Book chapters

Chapter 3: "The Impact of Gendered Roles in the Briquette Production and Supply Chain: Lessons Learned from Green Heat Ltd, Uganda" by Okello, G., Tumwesige, V., Angura, R. et al in Njenga, M., and Mendum, R., eds. 2018. Recovering Bioenergy in Sub-Saharan Africa: Gender Dimensions, Lessons and Challenges. Colombo, Sri Lanka: International Water Management Institute.



United Nations Environment Programme, Climate & Clean Air Coalition, African Union (2022). Integrated Assessment of Air Pollution and Climate Change for Sustainable Development in Africa - Summary for Decision Makers.

Gabriel Okello and Dr Jake Reynolds (2022). Pathways to e-mobility transitions in Uganda: Policy brief on transition to electric mobility. University of Cambridge Institute for Sustainability Leadership.

Gabriel Okello, Fredrick Mugisha, Irene Namaganda and William Avis. 2020. Understanding Household Fuel Transitions: The Case of Namuwongo (Kampala). A Systems Approach to Air Pollution – East Africa (ASAP-East Africa) project.

Gabriel Okello and William Avis (University of Birmingham). Systems of Cities: Urban Mobility in Kampala and its Surrounding Areas. (Under final review).


Peer reviewed journals

Okello, G., Nantanda, R., Awokola, B., Thondoo, M., Okure, D., Tatah, L., Bainomugisha, E., & Oni, T. (2023). Air quality management strategies in Africa: A scoping review of the content, context, co-benefits and unintended consequences. Environment International, 171, 107709.

Awokola, B., Okello, G., Johnson, O. et al (2022). Longitudinal Ambient PM2.5 Measurement at Fifteen Locations in Eight Sub-Saharan African Countries Using Low-Cost Sensors. Atmosphere 13, no. 10: 1593.  

Semple, S., Dobson, R., O’Donnell, R., Zainal Abidin, E., Tigova, O., Okello, G., & Fernández, E. (2022). Smoke-free spaces: A decade of progress, a need for more? Tobacco Control, 31(2), 250.

Woolley, K. E., Thomas, G. N., Kirenga, B., Okello, G., Kabera, T., Lao, X.-Q., Pope, F. D., Greenfield, S. M., Price, M. J., & Bartington, S. E. (2022). Association of household cooking location behaviour with acute respiratory infections among children aged under five years; a cross sectional analysis of 30 Sub-Saharan African Demographic and Health Surveys. Atmospheric Environment, 276, 119055. 

Singh, A., Dobbie, F., Kinnunen, T.I., Okello, G., Semple, S., Okyere, P.B., Logo, D.D., Lartey, K.F., McNeil, A., Britton, J., Bauld, L., & Owusu-Dabo, E.. (2021). Adherence to smoke-free policies in Ghana: Findings from a cross-sectional survey of hospitality venue owners and staff. Tobacco Prevention & Cessation, 7(January), 4. 

Awokola, B.I., Okello, G., Mortimer, K.J., Jewell, C.P., Erhart, A., & Semple, S. (2020). Measuring Air Quality for Advocacy in Africa (MA3): Feasibility and Practicality of Longitudinal Ambient PM(2.5) Measurement Using Low-Cost Sensors. International Journal of Environmental Research and Public Health, 17(19).  

Okello, G., Mortimer, K., Lawin, H. & Semple, S. 2020. Quantifying exposure to respiratory hazards in sub-Saharan Africa: a simple guide to some practical issues to help plan your study. AJRM 14, no 2.

Singh, A., Okello, G., Semple, S., Dobbie, F., Kinnunen, T.I., Lartey, K.F., Logo, D.D., Bauld, L., Ankrah, S.T., McNeill, A. & Owusu-Dabo, E. 2020. Exposure to secondhand smoke in hospitality settings in Ghana: Evidence of changes since implementation of smoke- free legislation. Tob. Induc. Dis. 2020;18(May):44

Okello G., Mortimer, K., Lawin, H., and Semple, S.. 2019. Quantifying exposure to respiratory hazards in sub-Saharan Africa: a simple guide to some practical issues to help plan your study. AJRM. Vol 14 No 2

Okello, G., Devereux, G. and Semple, S. 2018, "Women and girls in resource poor countries experience much greater exposure to household air pollutants than men: Results from Uganda and Ethiopia", Environment International, vol. 119, pp. 429-437

Gravely S, Nyamurungi KN, Kabwama SN, Okello G, Robertson L et al. 2018. Knowledge, opinions and compliance related to the 100% smoke-free law in hospitality venues in Kampala, Uganda: cross-sectional results from the KOMPLY Project. BMJ Open 2018;8:e017601. doi:10.1136/ bmjopen-2017-017601

Tumwesige, V., Okello, G., Semple, S., Smith, J. 2017. Impact of partial fuel switch on household air pollutants in sub-Sahara Africa. Environmental Pollution 231 (1)1021-1029.

Okello, G. 2017. Assessing Personal Exposure to Biomass fuel smoke in sub-Saharan Africa using GPS and Time-Activity Diaries data. Global Positioning System in Health Research Network. Issue Number: 11.


Online articles

Okello, G. (2021) Could electric motorcycles (e-bodas) reduce air pollution in Kampala and other rapidly growing African cities? UrbanBetter.

Okello, G. and Thondoo, M. (2023) Air pollution is a hidden pandemic in Africa - tips on how to reduce your exposure and help combat itThe Conversation.

Okello, G. (2022). Effective collaboration is a crucial pathway to tackling air pollution, climate change. NewVision.


Online outputs

RE:TV Terra Carta film showcasing sustainability conversation pivots and how policy, business, and finance leaders can accelerate transition to a sustainable economy that delivers for people, nature and climate. Available at:

RE:TV documentary film, entitled ‘Recirculating plastic’. 2021. This documentary film showcases innovation around plastic recycling and creating of green jobs (decent work). Available at:

Webinar for Air Quality, Urban Mobility and Governance in Kampala: an urbanising African city context. 2021. Available at:

Dr Gabriel  Okello
Prince of Wales Research Fellow

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