Sample bottles

Journal Article Provides Further Evidence of Firefighter Exposures Through Skin and Importance of Rapid, Thorough Cleaning

May 25, 2022

The "Firefighters’ urinary concentrations of VOC metabolites after controlled-residential and training fire responses" peer-reviewed journal article, led by FSRI Advisory Board member Kenneth Fent and NIOSH’s Alex Mayer along with several co-authors from the FSRI and IFSI teams has been published in the International Journal of Hygiene and Environmental Health.

Firefighters are exposed to volatile organic compounds (VOCs) during structural fire responses and training fires, several of which (e.g., benzene, acrolein, styrene) are known or probable carcinogens. Exposure studies have found that firefighters can absorb chemicals like benzene even when self-contained breathing apparatus (SCBA) are worn, suggesting that dermal absorption contributes to potentially harmful exposures. However, few studies have characterized VOC metabolites in urine from firefighters. 

The purpose of this paper is to quantify and compare specific VOC metabolites in urine across two studies that included simulated fireground responses and training fire responses. Firefighters and firefighter students responded to a single fire scenario. A spot urine sample was collected before and three hours after the fire responses. Urine was also collected from instructors each day before they led three training scenarios and three hours after the training scenarios. 

Samples were analyzed for metabolites of VOCs to which firefighters may be exposed. 


In the residential fire study, urinary metabolites of xylenes (2MHA), toluene (BzMA), and styrene (MADA) increased significantly from pre- to post-fire. In the training fire study, MADA concentrations increased significantly from pre- to post-fire for both firefighter students and instructors. Urinary concentrations of benzene metabolites (MUCA and PhMA) increased significantly from pre- to post-fire for instructors, while metabolites of xylenes (3MHA+4MHA) and acrolein (3HPMA) increased significantly for firefighter students. The two highest MUCA concentrations measured post-shift from instructors exceeded the BEI of 500 µg/g creatinine. 


Some of the metabolites that were significantly elevated post-fire are known or probable human carcinogens ; thus, exposure to these compounds should be eliminated or reduced as much as possible through the hierarchy of controls. Given stringent use of SCBA, it appears that dermal exposure contributes in part to the levels measured here. 

This study provides further evidence that firefighters’ exposure to volatile organic compounds produced during structure fires and training fires can occur through the skin. Fire officers and training officers can make firefighters aware of these risks by highlighting the importance of cleaning the skin as rapidly and thoroughly as possible.

This manuscript is a component of the Cardiovascular & Chemical Exposure Risk in Today’s Fire Service. Data comes from a secondary analysis comparing samples collected from both the Fireground Study and the Training Fires Study. In particular, it is related to these manuscripts:

This study was supported by the U.S. Department of Homeland Security, Assistance to Firefighters Grant program (EMW-2013-FP-00766; EMW-2014-FP-00590; EMW-2016-FP-00379) and made possible through agreement with the CDC Foundation. The findings and conclusions in this paper are those of the authors and do not necessarily represent the official position of the National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention.

Click here to download the article.


About International Journal of Hygiene and Environmental Health:

The International Journal of Hygiene and Environmental Health serves as a multidisciplinary forum for original reports on exposure assessment and the reactions to and consequences of human exposure to the biological, chemical, and physical environment. Research reports, short communications, reviews, scientific comments, technical notes, and editorials will be peer-reviewed before acceptance for publication. Priority will be given to articles on epidemiological aspects of environmental toxicology, health risk assessments, susceptible (sub) populations, sanitation and clean water, human biomonitoring, environmental medicine, and public health aspects of exposure-related outcomes.

Assessing the Cardiovascular and Chemical Risks Faced by Firefighters
Cardiovascular and Chemical Exposure Risks on Today’s Training Ground