Abstract
Abstract Benzene, toluene, ethylbenzene, and xylene (BTEX) are a group of volatile organic compounds that human exposure to them may result in the development of some diseases, including cancer. Biological monitoring plays an important role in exposure assessment of workers occupationally exposed to chemicals. Several metabolites have been proposed for biological monitoring of individuals who are exposed to BTEX. There are a variety of extraction methods and analytical techniques for the determination of unmetabolized BTEX in exhaled air and their urinary metabolites. The present study aimed to summarize and review the toxicokinetics of BTEX and sample preparation and analytical methods for their measurement. Metabolites of BTEX are discussed to find out reliable ones for biological monitoring of workers exposed to these chemicals. In addition, analytical methods for unmetabolized BTEX in exhaled air and their metabolites were reviewed in order to obtain a comparison between them in term of selectivity, sensitivity, simplicity, time, environmental-friendly and cost. Given the recent trends in sample preparation, including miniaturization, automation, high-throughput performance, and on-line coupling with analytical instrument, it seems that microextraction techniques, especially microextraction by packed sorbents are the methods of choice for the determination of the BTEX metabolites.
Highlights
BTEX are volatile organic compounds (VOCs), consisting benzene, toluene, ethylbenzene, and xylene
According to the American Conference of Governmental Industrial Hygienists (ACGIH), “BEI® represents the levels of determinants that are most likely to be observed in specimens collected from healthy workers who have been exposed to chemicals to the same extent as workers with inhalation exposure at the threshold limit value–timeweighted average (TLV-TWA) [21]
Exhaled air and urine can be used as reliable and easyto-collect media for biological monitoring (BM) of workers exposed to BETX
Summary
BTEX are volatile organic compounds (VOCs), consisting benzene, toluene, ethylbenzene, and xylene. End of shift End of shift Prior to last shift of workweek End of shift End of shift End of shift at end of workweek End of shift aACGIH – threshold limit value-time weighted average bOSHA – permissible exposure limit-time weighted average cNIOSH – recommended exposure limit-time weighted average dBEIs – biological exposure indices tt-MA – trans,trans-muconic acid; MA – mandelic acid; MHA-methylhippuric acid; PGA – phenylglyoxylic acid; o-cresol – ortho-cresol; PMA – S-phenylmercapturic acid; Occupational exposure to chemicals can be assessed using air monitoring and/or biological monitoring (BM) In the former, air samples are collected in the breathing zones of the workers on a sampling medium in an active or passive way [14]. In passive sampling, containers or badges which collect chemicals based on diffusion are used Air monitoring makes it possible to determine the airborne levels of contaminants that a subject is exposed via inhalation [15,16,17]. The primary focus is on the techniques reported in the last 15 years for BTEX metabolites
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
