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The William Harvey Research Institute - Faculty of Medicine and Dentistry

Professor Nikolas P Lemos

Nikolas P

Director, Cameron Forensic Medical Sciences & Professor of Forensic Medical Sciences

Centre: Clinical Pharmacology and Precision Medicine

Telephone: +44(0) 20 7882 2576
Twitter: @ProfNPLemos 


Professor Lemos is a chartered forensic scientist who started his career in the field for analytical and forensic toxicology researching drug analysis in fingernails and other biological specimens. Lemos worked as Senior Lecturer at London South Bank University where he helped develop a new undergraduate course in forensic science. In 2001, he moved to St George’s University of London to be Head of the Forensic Toxicology Service of its Analytical Unit where he supervised the provision of toxicologic services to HM Coroners, Home Office Pathologists and Police Forces and co-supervised the research of numerous medical and graduate students who trained in the Analytical Unit.

In 2003, he became Chief Forensic Toxicologist and Director of the Forensic Laboratory Division at the Office of the Chief Medical Examiner of the City and County of San Francisco in California, USA. Professor Lemos co-ordinated the efforts of forensic pathologists, toxicologists, investigators and scientists towards accreditations by the National Association of Medical Examiners (NAME) and the American Board of Forensic Toxicologists (ABFT). He also spearheaded the design of the forensic laboratory spaces of the new Medical Examiner’s facility in San Francisco.

Lemos has academic affiliations in San Francisco, St Louis, and Athens. He is actively engaged in various national and international professional organizations and is a Member of the Chartered Society of Forensic Scientists, Fellow of the American Board of Forensic Toxicologists, Fellow of the Royal Society of Chemistry, and Fellow of the American Academy of Forensic Sciences. In 2018, Lemos was elected Chair of the Toxicology Section of the American Academy of Forensic Sciences.

Lemos consults and testifies in criminal and civil cases around the world. He has testified in over 325 cases and has offered opinions to assist the courts in response to subpoenas issued by both prosecutors as well as defence attorneys. He has organized and hosted numerous professional scientific meetings in the UK and USA including the 2011 Joint SOFT-TIAFT Meeting with over 1,500 participants from 60 countries.

He has co-authored over 85 peer-reviewed papers, abstracts, and book chapters including the first ever study of Cannabinoids in Fingernails (JAT, May 1999) and the first ever study of Cannabinoids in post mortem Toxicology (JAT, September 2011). He has previously served as Science Editor of Medicine, Science and the Law, the official journal of the British Academy of Forensic Sciences, and he is the holder of many scholarships, research and equipment grants and awards. In 2005 he was honoured with a Proclamation of Achievement by the 109th Congress of the United States of America “for dedicating his life and career to community safety and social awareness.”

Social Media

X: @ProfNPLemos 
Facebook: Prof Nikolas P Lemos 


  • Human Performance Forensic Toxicology
  • Toxicology of Driving Under the Influence Cases
  • Toxicology and Drug-Facilitated Crimes
  • Hair, Nail and Other Keratinous Matrices in Forensic Toxicology
  • Post mortem Forensic Toxicology
  • Post mortem Redistribution and Post mortem Interval in Forensic Toxicology
  • Pharmacology and Toxicology of Cannabis
  • Analytical and Forensic Laboratory Accreditation
  • Development and Validation of Analytical Methods in Forensic Toxicology
  • Epidemiology of Drugs and Poisons

Key Publications

  • Andreuccetti, G, CJ Cherpitel, HB Carvalho, V Leyton, ID Miziara, DR Munoz, AL Reingold, NP Lemos. Alcohol in combination with illicit drugs among fatal injuries in Sao Paulo, Brazil: An epidemiological study on the association between acute substance use and injury. Injury. 2018;49(12):2186-2192.
  • Hurstak, E, C Rowe, C Turner, E Behar, R Cabugao, NP Lemos, C Burke, P Coffin. Using medical examiner case narratives to improve opioid overdose surveillance. International Journal of Drug Policy. 2018; 54:35–42.
  • Andreuccetti, G, V Leyton, NP Lemos, ID Miziara, Y Ye, J Takitane, DR Munoz, AL Reingold, CJ Cherpitel, HB de Carvalho. Alcohol Use Among Fatally Injured Victims in Sao Paulo, Brazil: Bridging the Gap between Research And Health Services In Developing Countries. Addiction. 2017;112(4):596-603.
  • Labay, LM, JL Caruso, TP Gilson, R Jufer-Phipps, LD Knight, NP Lemos, IM McIntyre, R Stoppacher, LM Tormos, AL Weins, E Williams, R Zumwalt, BK Logan. Synthetic Cannabinoid Drug Use as a Cause or Contributory Cause of Death. Forensic Science International. 2016;260:31-39.
  • Lemos, NP, AC San Nicolas, JA Volk, EA Ingle and CM Williams. Driving Under the Influence of Marijuana versus Driving and Dying Under the Influence of Marijuana: A Comparison of Blood Concentrations of Δ9-Tetrahydrocannabinol, 11-hydroxy-Δ9-tetrahydrocannabinol, 11-nor-9-Carboxy-Δ9-Tetrahydrocannabinol and Other Cannabinoids in Arrested Drivers versus Deceased Drivers. Journal of Analytical Toxicology. 2015;39:588–601.
  • San Nicolas AC, NP Lemos, Toxicology findings in cases of hanging in the City and County of San Francisco over the 3-year period from 2011 to 2013, Forensic Science International. 2015;255:146–155.
  • Visconti, AJ, GM Santos, NP Lemos, C Burke and PO Coffin. Opioid Overdose Deaths in the City and County of San Francisco: Prevalence, Distribution, and Disparities, Journal of Urban Health. 2015;92(4):758-72.
  • Lemos NP. Driving Under the Influence of Synthetic Cannabinoid Receptor Agonist XLR-11, Journal of Forensic Sciences. 2014;59(6):1679-83.
  • Lemos NP. Ethanol Analysis in Postmortem and Human Performance Forensic Toxicology Cases, Academic Forensic Pathology. 2014;4(2):138-45.
  • Lung DD and NP Lemos. Fentanyl: Cause of Death or Incidental Finding? Postmortem Peripheral Blood Concentrations with and without Documented Transdermal Patch Use, Forensic Toxicology 2014;32(1):118–25.
  • Melinek J and NP Lemos. Forensic Considerations in Bariatric Surgery Patients, Academic Forensic Pathology. 2013;3(1):13–21.
  • Lemos NP and EA Ingle. Cannabinoids in Postmortem Toxicology. Journal of Analytical Toxicology. 2011;35(7):394–401.
  • Lemos NP. Methamphetamine and Driving. Science & Justice. 2009;49(4):247–9.
  • Lemos NP. Postcard from America – post-mortem forensic toxicology. Medicine, Science and the Law. 2005;45(3):185–6.
  • Lemos NP, F Bortolotti, G Manetto, RA Anderson, F Cittadini and F Tagliaro. Capillary Electrophoresis: A New Tool on Forensic Medicine & Science. Science and Justice. 2001;41:203–10.
  • Lemos NP, RA Anderson and JR Robertson. The Analysis of Methadone in Nail Clippings from Patients on a Methadone Maintenance Program. Journal of Analytical Toxicology. 2000;24(7):656–60.
  • Lemos NP, RA Anderson, R Valentini, F Tagliaro and RTA Scott. Analysis of Morphine by RIA and HPLC in Fingernail Clippings Obtained from Heroin Users. Journal of Forensic Sciences. 2000;45(2):414–9.
  • Lemos NP, RA Anderson and JR Robertson. Nail Analysis for Drugs of Abuse: Extraction and Determination of Cannabis in Fingernails by RIA and GC-MS. Journal of Analytical Toxicology. 1999; 23(3):147–52.
  • Agarwal AK and NP Lemos. Significance of Bile Analysis in Drug-Induced Deaths. Journal of Analytical Toxicology. 1996;20(1):61–3.


  • Westminster Coroner
  • Southwark Coroner
  • Metropolitan Police
  • City of London Police
  • Natural History Museum
  • St George’s, University of London
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