Health risk associated with inhalation exposure to aromatic hydrocarbons (BTEX) in the City of Novi Sad

Road traffic is one of the major sources of air pollutants, including aromatic hydrocarbons. The current study assessed the presence of benzene, toluene, ethylbenzene and xylenes (BTEX) in the City of Novi Sad's ambient air and the health risk for its inhabitants.

A total of 686 24h air samples were collected at two sites in the City of Novi Sad during 2024 and analyzed using a GC-MS method.

As expected on traffic sites, BTEX compounds were quantified in the majority of the samples: toluene 94.3% > benzene 88.3% > xylenes 75.6% > ethylbenzene 59.0%. The mean concentrations (µg/m³) of benzene and toluene were higher at urban traffic sites (1.7 vs. 1.3; 3.9 vs. 2.3), while ethylbenzene and xylenes reached higher means at suburban traffic sites (1.0 vs. 1.7; 2.6 vs. 4.2). Benzene's annual concentration was in compliance with the calendar year limit established by Directive 2008/50/EC. The hazard index (HI), calculated as a sum of hazard quotients related to reference inhalation concentrations of individual compounds, was used as a measure of non-carcinogenic risk. The HI values on suburban (0.087) and urban traffic sites (0.085) indicated no health risk. Benzene and xylenes were the main HI contributors (>98%). The carcinogenic risk was based on benzene and ethylbenzene inhalation risk units. In the case of children, it was very similar on suburban and urban traffic sites (2.1E-06 and 2.3E-06), while in the case of adults, it was slightly higher on urban traffic sites (9.1E-06 vs. 8.2E-06). However, the health risk was low regardless of the population group. As expected, due to its higher inherent carcinogenic potential as well as its higher population exposure level, benzene showed a 2.5-fold higher impact on carcinogenic risk than ethyl benzene.

Although the estimated values ​​of the risk indicators are low, it is of utmost importance to reduce exposure to carcinogenic compounds in ambient air.