Mark Nicas PhD, MPH, CIH

Emeritus, Adjunct Professor, Environmental Health Sciences
Director, Industrial Hygiene Program
  • PhD - University of California, Berkeley, 1991
  • PH 270A: Exposure Assessment and Control I
  • PH 298-002: Exposure Assessment and Control II
Research Interests: 
  • Microbial exposure and risk assessment
  • Chemical toxicant exposure and risk assessment
  • Variability in respiratory protecton
  • Mathematical modeling of exposure to indoor air pollutants
  • Risk modeling of infection by airborne pathogens
Research Description: 

Dr. Nicas pursues research involving exposure/risk assessment for microbial pathogens and chemical toxicants. He investigates the transmission of respiratory infections by multiple exposure routes (inhalation of small and large cough particles, surface-to-hand-to-mucous membrane contact, droplet spray). He developed a Markov chain model that integrates exposure along these pathways, and has applied the model to pathway-apportionment of influenza transmission. He has developed models for the emission and dispersion of chemical pollutants in indoor air. Earlier work involved the risk of M. tuberculosis infection/disease among health care workers, and the efficacy of respiratory protection against airborne pathogens and chemical toxicants.

Current Projects: 
  • investigation of droplet spray exposure
  • investigation of influenza transmission pathways
Selected Publications: 

Nicas M, Jones RM. (2009) Relative contributions of four exposure pathways to influenza infection risk, Risk Analysis. 29:1292-1303

Jones RM, Nicas M. (2009) Experimental determination of supermicrometer particle fate subsequent to a point release within a room under natural and forced mixing. Aerosol Science Technol. 43:921-938

Nicas M, Neuhaus J. (2008) Predicting benzene vapor concentrations with a near field/far field model. J. Occup. Environ. Hyg. 5:559-568

Nicas M and RM Jones (2008) Relative Contributions of Four Exposure Pathways to Influenza Infection Risk, Risk Analysis, in review

Jones, RM, Y Masago, T Bartrand, C Haas, M Nicas and J Rose (2008) Characterizing the Risk from Mycobacterium tuberculosis in Commercial Passenger Aircraft using Quantitative Microbial Risk Assessment, Risk Analysis, in press

Nicas M and J Neuhaus (2008) Predicting Benzene Vapor Concentrations with a Near Field/Far Field Model, J. Occup. Environ. Hyg. 5:559-568

Nicas M and D Best (2008) A Study Quantifying the Hand-to-Face Contact Rate and Its Potential Application to Predicting Respiratory Tract Infection, J. Occup. Environ. Hyg. 5:347-352

Nicas M and G Sun (2006) An Integrated Model of Infection Risk in a Health Care Environment, Risk Analysis26:1097-1108

Nicas M (2005) Use of a Probabilistic Infectious Dose Model for Estimating Airborne Pathogen Infection Risk: Application to Respiratory Protection, J. Int. Soc. Respir. Prot. 22:24-37

Nicas M, W Nazaroff and A Hubbard (2005) Toward Understanding the Risk of Secondary Airborne Infection: Emission of Respirable Pathogens, J. Occup. Environ. Hyg. 2:134-145

Nicas M, A Hubbard, R Jones and A Reingold (2004) The Infectious Dose of Variola (Smallpox) Virus, Appl. Biosafety9:118-127

Nicas M and J Neuhaus (2004) Variability in Respiratory Protection and the Assigned Protection Factor, J. Occup. Environ. Hyg. 1: 99-109

Nicas M (2003) Estimating Methyl Bromide Exposure due to Offgassing from Fumigated Commodities, <em "="">Appl. Occup. Environ. Hyg. 18:200-210

Nicas M and A Hubbard (2002) A Risk Analysis for Airborne Pathogens with Low Infectious Doses: Application to Respirator Selection against Coccidioides immitis Spores, Risk Anal. 22:1153-1163

Nicas M and M Jayjock (2002) Uncertainty in Exposure Estimates Made by Modeling versus Monitoring, Am. Ind. Hyg. Assoc. J. 63:275-283

Nicas M (2001) Modeling Turbulent Diffusion and Advection of Indoor Air Contaminants by Markov Chains, Am. Ind. Hyg. Assoc. J. 62:149-158

Nicas M (2000) Regulating the Risk of Tuberculosis Transmission among Health Care Workers, Am. Ind. Hyg. Assoc. J.61:334-339

Other interests: 
  • Editor in Chief, Journal of Occupational and Environmental Hygiene (JOEH)
  • Member, American Industrial Hygiene
  • Association Member, Society for Risk Analysis
  • Member, American Biiological Safety Association
  • Exposure Assessment Strategies Committee, American Industrial Hygiene Association
Profile Updated: November 15, 2018