| Title: | Exposure levels and health risk assessment of ambient BTX at urban and rural environments of a terai region of northern India |
| Author(s): | Masih A; Lall AS; Taneja A; Singhvi R; |
| Address: | "Environmental Research Lab, Department of Chemistry, St. Andrew's College, Gorakhpur, India. Environmental Research Lab, Department of Chemistry, St. Andrew's College, Gorakhpur, India. Electronic address: anuragsam7son@gmail.com. Department of Chemistry, Dr. BhimRaoAmbedkar University, Agra, India. Environment Response Team, United States Environment Protection Agency, New Jersey, USA" |
| DOI: | 10.1016/j.envpol.2018.07.107 |
| ISSN/ISBN: | 1873-6424 (Electronic) 0269-7491 (Print) 0269-7491 (Linking) |
| Abstract: | "Benzene, toluene and xylene (BTX) belong to an important group of aromatic volatile organic compounds (VOCs) that are usually emitted from various sources. BTX play a vital role in the tropospheric chemistry as well as pose health hazard to human beings. Thus, an investigation of ambient benzene, toluene and xylene (BTX) was conducted at urban and rural sites of Gorakhpur for a span of one year in order to ascertain the contamination levels. The sampling of BTX was performed by using a low-flow SKC Model 220 sampling pump equipped with activated coconut shell charcoal tubes with a flow rate of 250?ª+ml/min for 20-24?ª+h. The analysis was in accordance with NIOSH method 1501. The efficiency of pump was checked weekly using regulated rotameters with an accuracy of +/-1%. The samples were extracted with CS(2) with occasional agitation and analyzed by GC-FID. The total BTX concentration ranged from 3.4?ª+mug?ª+m(-3) to 45.4?ª+mug?ª+m(-3) with mean value 30.95?ª+mug?ª+m(-3) and median 24.8?ª+mug?ª+m(-3). The mean concentration of total BTX was maximum during winter (39.3?ª+mug?ª+m(-3)), followed by summer (28.4?ª+mug?ª+m(-3)) and monsoon season (25.1?ª+mug?ª+m(-3)). The mean concentration of BTX at urban site (11.8?ª+mug?ª+m(-3)) was higher than that at rural site (8.8?ª+mug?ª+m(-3)). At both the sites, T/B and X/B ratios were highest in monsoon and lowest in winters. Toluene against benzene plot shows R(2) value of 0.96 and 0.49?ª+at urban and rural sites respectively. Higher R(2) value at urban site clearly indicates similar sources of emission for benzene and toluene. At both the sites, the estimated integrated lifetime cancer risk (ILTCR) for benzene exceeded the threshold value of 1E-06 whereas the individual hazard quotients (HQ) for BTX did not exceed unity at any of the sites" |
| Keywords: | Air Pollutants/*analysis Benzene/*analysis Environmental Monitoring Humans India Neoplasms/epidemiology Risk Risk Assessment Rural Population Seasons Toluene/*analysis Urban Population Xylenes/*analysis Btx Hq Iltcr Terai zone Urban & rural environments; |
| Notes: | "MedlineMasih, Amit Lall, Anurag S Taneja, Ajay Singhvi, Raj eng EPA999999/ImEPA/Intramural EPA/ England 2018/08/05 Environ Pollut. 2018 Nov; 242(Pt B):1678-1683. doi: 10.1016/j.envpol.2018.07.107. Epub 2018 Jul 24" |
