Special Session on Better Air Quality in Asia (II)

Noor Fatihah Mohamad Fandi1, Juliana Jalaludin This email address is being protected from spambots. You need JavaScript enabled to view it.1,2, Mohd Talib Latif3, Haris Hafizal Abd Hamid3, Mohd Fairus Awang1

1 Department of Environmental and Occupational Health, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
2 Department of Occupational Health and Safety, Faculty of Public Health, Universitas Airlangga, 60115 Surabaya, East Java, Indonesia
3 Department of Earth Sciences and Environment, Faculty Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia


Received: November 12, 2019
Revised: June 10, 2020
Accepted: June 18, 2020

 Copyright The Author(s). This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are cited.

Download Citation: ||https://doi.org/10.4209/aaqr.2019.11.0574  

Cite this article:

Fandi, N.F.M., Jalaludin, J., Latif, M.T., Hamid, H.H.A. and Awang, M.F. (2020). BTEX Exposure Assessment and Inhalation Health Risks to Traffic Policemen in the Klang Valley Region, Malaysia. Aerosol Air Qual. Res. 20: 1922–1937. https://doi.org/10.4209/aaqr.2019.11.0574


  • Personal exposure to toluene was highest among the outdoor traffic policemen.
  • T/B ratio value shows vehicle emissions are the main source of BTEX.
  • CR value of benzene and ethylbenzene at 95th percentile exceeded acceptable limit.
  • Exposure duration and BTEX concentrations had influenced on the estimated risks.
  • RPE with organic vapor and particle cartridge is effective in reducing cancer risk.


Benzene, toluene, ethylbenzene, m,p-xylene, and o-xylene (collectively referred to as BTEX), which are prevalent in the ambient air of urban environments, potentially cause chronic health effects, particularly among outdoor workers. Aim of this study was to evaluate BTEX concentrations in the Klang Valley of Malaysia and assess the health risks to urban traffic police officers, whose duties include controlling the traffic flow and enforcing traffic laws. Air samples were collected with low-flow personal samplers during the officers’ work shifts outdoors, and the BTEX content was then analyzed via gas chromatography-mass spectrometry (GC-MS) coupled with thermal desorption (TD). A probabilistic method based on Monte Carlo simulation was applied to determine the cancer risk (CR) and hazard quotient (HQ), and a sensitivity analysis was performed to identify the greatest contributors to the estimated risks. The total BTEX concentration in the samples averaged 211.83 µg m–3, with the largest component being toluene (averaging 89.08 µg m–3 in concentration), followed by m,p-xylene (37.25 µg m–3), o-xylene (35.80 µg m–3), benzene (25.82 µg m–3), and ethylbenzene (23.89 µg m–3). The average CR value for benzene (5.31 × 10–6) as well as the 95th percentiles of the CR values for benzene and ethylbenzene (1.70 × 10–5 and 2.12 × 10–6, respectively) exceeded the acceptable level of exposure (1.0 × 10–6). The HQ values for all of the BTEX species were less than one. The sensitivity analysis revealed that the most influential parameter in increasing the estimated CR and HQ was the exposure duration, followed by the BTEX concentration. The estimated CR indicates that the prolonged exposure to benzene and ethylbenzene experienced by traffic police officers exacerbates the risk of adverse health effects. These results, which provide baseline data for determining the occupational risk to individuals who are exposed to BTEX while working on or near a road, emphasize the need for additional regulations, including the use of appropriate respiratory protective equipment.

Keywords: BTEX; Urban traffic police officers; Health risk assessment; Sensitivity analysis; Klang Valley.

Aerosol Air Qual. Res. 20 :1922 -1937 . https://doi.org/10.4209/aaqr.2019.11.0574  

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