---

PH 270A Exposure Assessment and Control (F) [description]
 

---

Ongoing research projects:

• Mathematical modeling of contaminant emission and dispersion in air
• Probability modeling of airborne infectious disease transmission

Dr. Nicas has two primary research interests. First, he develops mathematical models to estimate exposure intensity to airborne chemical toxicants. Such models consider the pollutant emission rate and the dispersion pattern in air. Dr. Nicas uses two approaches - a traditional method based on deterministic differential equations and a probabilistic method involving Markov chain techniques. Second, he develops probability models for infection by airborne pathogens (e.g., M. tuberculosis, Y. pestis, C. immitis), with an immediate application to the risk-based selection of personal respiratory protection. Past research involved probability modeling of variability in the efficiency of personal respiratory protection, and theoretical risk analyses for M. tuberculosis infection and disease incidence among health care workers.
 

---

Recent Papers on Mathematical Modeling of Exposure Intensity
 
Nicas M, Plisko MJ, Spencer JW (2006) Estimating benzene exposure at a solvent parts washer. J Occup Environ Hyg. 3(5):284-91 [abstract]
 
Nicas M, Armstrong TW (2003) Computer implementation of mathematical exposure modeling. Appl Occup Environ Hyg. 18(8):566-71. [abstract]
 
Keil CB, Nicas M (2003) Predicting room vapor concentrations due to spills of organic solvents. AIHA J (Fairfax, Va). 64(4):445-54. [abstract]
 
Nicas M (2003) Estimating methyl bromide exposure due to offgassing from fumigated commodities. Appl Occup Environ Hyg. 18(3):200-10. [abstract]
 
Nicas M (2003) Using mathematical models to estimate exposure to workplace air contaminants. Chem Health Safety. 10(1):14-21. [abstract]
 
Nicas M, Jayjock M (2002) Uncertainty in exposure estimates made by modeling versus monitoring. AIHA J (Fairfax, Va). 63(3):275-83. [abstract]
 
Nicas M (2001) Modeling turbulent diffusion and advection of indoor air contaminants by Markov chains. AIHAJ. 62(2):149-58. [abstract]
 
Recent Papers on Infection by Airborne Pathogens
 
Nicas M, Sun G (2006) An integrated model of infection risk in a health care environment. Risk Anal. In press.
 
Jones RM, Nicas M, Hubbard A, Reingold A (2006) The infectious dose of coxiella burnetii (Q Fever). Appl Biosafety. 11:32-41.
 
Jones RM, Nicas M, Hubbard A, Sylvester M, Reingold A (2005) The infectious dose of Francisella tularensis (Tularemia). Appl Biosafety. 10:277-239.
 
Nicas M (2005) Use of a probabilistic infectious dose model for estimating airborne pathogen infection risk. J Intl Society for Respiratory Protection. 22:24-37.
 
Nicas M, Nazaroff WW, Hubbard A (2005) Toward understanding the risk of secondary airborne infection: emission of respirable pathogens. J Occup Environ Hyg. 2(3):143-54. [abstract]
 
Nicas M, Hubbard AE, Jones RM, Reingold AL (2004) The infectious dose of Variola (smallpox) virus. Appl Biosafety. 9(3):118-127.
 
Nicas M, Hubbard A (2002) A risk analysis for airborne pathogens with low infectious doses: application to respirator selection against Coccidioides immitis spores. Risk Anal. 22(6):1153-63. [abstract]
 
Nicas M, Neuhaus J, Spear RC (2000) Risk-based selection of respirators against infectious aerosols: application to anthrax spores. J Occup Environ Med. 42:737-748 [abstract]