Variability in the Levels of BTEX at a Pollution Hotspot in New Delhi, India

It is a matter of concern that despite taking measures to control aromatic content in gasoline in India, the levels of volatile organic compounds are rising again in many of the Indian cities. The transport sector has been one of the major sectors which are re-sponsible for worsening the air quality of Delhi city. While thousands of toxic com-pounds are emitted from automobiles, industries, gasoline stations as well as service stations, however, volatile organic compounds are important due to their significant contribution to ozone formation, cancer, and non-cancer health risks. In this study, roadside levels of benzene, toluene, ethylbenzene and xylenes (BTEX) were investi-gated at the one of the major arterial road of Delhi city. Air samples were collected by activated coconut shell charcoal adsorbent tubes. The BTEX concentrations were de-termined by gas chromatography-flame ionization detector (GC-FID) technique. The mean concentrations of benzene, toluene, ethylbenzene and xylenes were, respectively, 60.22, 162.68, 49.42 and 25.25 μg/m3. The relative concentration distribution pattern and mutual correlation analysis indicated that in BTEX had sources other than vehicle emission at the study site. The samples collected, showed that BTEX had significantly higher concentrations in winter than those in spring and summer.