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Professor Claire Horwell

Professor of Geohealth

Professor of Geohealth in the Department of Earth Sciences+44 (0) 191 33 42253
Fellow of the Wolfson Research Institute for Health and Wellbeing+44 (0) 191 33 42253
Management Board Member in the Institute of Hazard, Risk and Resilience+44 (0) 191 33 42253


2019 - present


IHRR & Department of Earth Sciences, Durham University, UK

2014 - present Honorary Professor

UK Health & Security Agency (formerly PHE/HPA)

2012 - 2019 Lecturer/Sr Lecturer/Reader/Assoc Prof IHRR & Department of Earth Sciences, Durham University, UK
2012 - 2016 Co-Director IHRR, Durham University, UK
2011 - present Fellow Wolfson Institute for Health & Wellbeing, Durham University, UK
2003 - present Director International Volcanic Health Hazard Network
2007 - 2012 RCUK & NERC Fellow IHRR & Department of Earth Sciences, Durham University, UK
2005 - 2007 NERC Fellow Department of Earth Science, University of Cambridge, UK
2003 - 2005 Leverhulme Trust PDRA School of Earth Science, University of Bristol, UK
1999 - 2002 NERC CASE PhD student School of Earth Science, University of Bristol, UK
Career Research Highlights

I am founder/director of the International Volcanic Health Hazard Network, the umbrella organisation for volcanic health research and dissemination. I have acted as advisor to the World Health Organization, Public Health England and the UK Cabinet Office regarding the respiratory health hazards of volcanic ash. I also work with government and non-governmental agencies, around the world, helping them to prepare the health response for future volcanic eruptions, and responding during volcanic crises.

My research interest is in understanding the health hazards of natural and industrial mineral dusts and in helping communities to prepare for, and protect themselves from volcanic emissions and other particulate pollution crises. My research is split into several, interdisciplinary strands, which are conducted with multiple UK and international collaborators across the natural, social and medical sciences:

Are mineral particles harmful when inhaled?

i) Physicochemical analysis of particles: use of mineralogical and geochemical techniques to assess respiratory hazard. These are combined with my students' and collaborators’ toxicological assessements to determine potential respiratory hazard of volcanic ash, combusted biomass, diatomaceous earth, desert dust and coal dust.

ii) Fundamental questions surrounding the ‘structure-toxicity’ relationship of mineral particles and interacting elements (e.g. anthropogenic pollution), and the variable toxicity of crystalline silica are also addressed through mineralogical, geochemical and toxicological analyses. Petrological techniques are also employed to understand how crystalline silica forms in volcanic systems (paricularly lava domes).

iii) Exposure assessments to airborne particles is a key part of determining potential hazard. My group conducts air quality assessments using state-of-the-art portable aerosol monitors.

How can communities prepare for, and protect themselves from, airborne particulate crises? 

iv) Working with GOs, NGOs and behavioural psychologists and social anthropologists, we conduct social research within local communities to understand their lifestyles, cultural contexts, and how their risk perceptions influence their protective behaviours. We also investigate how their current protective strategies relate to official advice. 

v) We assess the effectiveness of community use of respiratory protection (from industry-certified RPE to cloth face-coverings) through laboratory tests and field trials, in collaboration with exposure scientists and PPE experts at the Institute of Occupational Medicine. 

vi) With social learning experts, we work with communities and local authorities to co-develop evidence-based printable and audio visual informational products which inform people on the most effective protection strategies for exposure reduction to airborne pollutants. Our products are available at

vii) We evaluate the ethical and legal aspects of agencies distributing or recommending different forms of respiratory protection for community use. 

Committee and Society Service

2022 - 2024 - Member of the Royal Society's Research Grants Board

2020 - 2022 - Member of the European Geosciences Union's Plinius Medal Committee

2017- 2020- President (and former President-elect and Founding Leader); GeoHealth Section, American Geophysical Union

2017 - 2020 - Council Member, American Geophysical Union

2015 - present - Member; Scientific Advisory Group for Emergencies (SAGE) for volcanic eruptions, UK Government

2014 – 2017— Chair, Nominations & Awards Committee; International Medical Geology Association

2013 – 2015— Member; Expert Advisory Group for Risk H55, UK Government Cabinet Office

2011 – present — Member; Public Health England's expert panel for future ashfall affecting the UK

2011 – present — Member of Scientific Steering Committee and Project Partner; Global Volcano Model

2011 – 2014 — Chair, Education Committee; International Medical Geology Association

2010 – 2011 — Member; Scientific Advisory Committee for Iceland Eruptions; World Health Organization

2005 – 2007 — Representative for Health for the ICSU 5 GeoUnions Initiative; International Union of Geodesy and Geophysics


2007 – 2012 — Research Councils UK: Fellow

2005 – 2011 — NERC Postdoctoral Fellow


Chapter in book

Journal Article