Article
Assessment of Occupational Exposure to BTEX in a
Petrochemical Plant via Urinary Biomarkers
Višnja Mihajlovi´c
1
, Nenad Grba
2,
* , Jan Su
¯
di
3
, Diane Eichert
4
, Smilja Krajinovi´c
5
, Milivoj B. Gavrilov
6
and Slobodan B. Markovi´c
6
Citation: Mihajlovi´c, V.; Grba, N.;
Su
¯
di, J.; Eichert, D.; Krajinovi´c, S.;
Gavrilov, M.B.; Markovi´c, S.B.
Assessment of Occupational
Exposure to BTEX in a Petrochemical
Plant via Urinary Biomarkers.
Sustainability 2021, 13, 7178. https://
doi.org/10.3390/su13137178
Academic Editor: João Carlos de
Oliveira Matias
Received: 20 May 2021
Accepted: 21 June 2021
Published: 25 June 2021
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1
Department of Environmental Engineering, Technical Faculty “Mihajlo Pupin”, University of Novi Sad,
23101 Zrenjanin, Serbia; visnjamihajlovic@uns.ac.rs
2
Department of Chemistry, Biochemistry and Environmental Protection, Faculty of Sciences,
University of Novi Sad, 21000 Novi Sad, Serbia
3
Institute of Occupational Health, 21000 Novi Sad, Serbia; jansudy@yahoo.com
4
Elettra-Sincrotrone Trieste S.C.p.A, 34149 Trieste, Italy; diane.eichert@elettra.eu
5
Department of Environmental Engineering and Occupational Safety, Faculty of Technical Sciences,
University of Novi Sad, 21000 Novi Sad, Serbia; smilja.krajinovic@gmail.com
6
Department of Geography, Tourism and Hotel Management, Faculty of Sciences, University of Novi Sad,
21000 Novi Sad, Serbia; gavrilov.milivoj@gmail.com (M.B.G.); slobodan.markovic@dgt.uns.ac.rs (S.B.M.)
* Correspondence: nenad.grba@dh.uns.ac.rs; Tel.: +381-21-485-2724
Abstract:
This work presents the results of the first Serbian monitoring campaign performed to
assess the occupational exposure of petrochemical industry workers to benzene (B), toluene (T),
ethylbenzene (E), and xylene (X), known collectively as BTEX. The following urinary biomarkers
were investigated: phenol, hippuric acid, o-Cresol, p-Cresol, and creatinine. BTEX compounds were
collected in 2014 using Casella passive samplers. Multivariate statistical analysis was performed
to put in evidence the correlation between the BTEX measured in air and the concentration of
urinary biomarkers. While the results indicate an elevated presence of benzene in the air in the
working environment studied that surpasses the national and European Occupational Exposure
Limits (OEL), the levels of the remaining (TEX) parameters measured were below the OEL. The high
relative standard deviations (RSD) for the concentrations of each BTEX compound (
68–161 mg m
−3
)
point toward an intensive occupational exposure to BTEX. This was confirmed by relevant urine
biomarkers, particularly by the mean values of phenol, which were ten and fourteen times higher than
the ones found in the control group (14–12 mg g
−1
of creatinine). On average, workers are at a higher
risk of developing cancer (6.1
×
10
−3
), with risk levels exceeding the US EPA limits. Benzene levels
should therefore be maintained under tight controls and monitored via proper urinary biomarkers.
Keywords:
petrochemical industry; air pollution; BTEX; urine biomarkers; multivariate analysis;
carcinogenic risks
1. Introduction
Oil and petrochemical processing and production complexes present significant chal-
lenges for occupational health and industrial safety. Aromatic hydrocarbons such as
benzene, toluene, ethylbenzene, and xylene (collectively labeled as BTEX) are natural
components of the petroleum stream and solvents in various industries [1]. Occupational
exposure to these agents may occur during production processes, maintenance of process
systems, evaporation, or leaking of poorly maintained underground fuel tanks. The occu-
pational exposure to benzene is regulated in the European Union by occupational exposure
limits (OEL), which are 3.25 mg m
−3
for benzene [
2
]. According to the same EU legislation,
limiting values are 192 mg m
−3
for toluene, 442 mg m
−3
for ethylbenzene, and
221 mg m
−3
for xylene [
3
,
4
]. The national Serbian legislation for these compounds is aligned with the
European limits [
4
,
5
]. Recent studies using urinary biomarkers showed that in occupa-
Sustainability 2021, 13, 7178. https://doi.org/10.3390/su13137178 https://www.mdpi.com/journal/sustainability
