Amit Masih

Contamination and exposure profiles of priority Polycyclic Aromatic Hydrocarbons (PAHs) in groundwater in a semi-arid region in India

The concentration of 13 PAHs in groundwater was measured at 12 locations of Agra. The mean concentration of TPAH in all samples was 31.86 ng L−1 and it ranges from 13.2 ng L−1 to 64.3 ng L−1. The 4-ring and 5-ring PAHs were found to be dominant in the groundwater of Agra region having 38.6% and 26.4% of the TPAH. The carcinogenic potency was estimated and it was found 2.7 ng L−1. Univariate Pearson correlation matrix shows a good correlation among all PAHs except B(a)P. The levels of PAHs in the groundwater can help in environment risk assessment of this area.

Seasonal and diurnal characteristics of surface level O3 and its precursors in the north-central part of India

Surface measurements of ozone and its precursor gases NO2 and CO have been made over an urban site of Agra (semi-arid region) for year 2005. O3, NO2 and CO show diurnal variations during all seasons. Overall increased concentration of O3 is majority attributed to increase in concentrations of NO2 and CO. The highest average concentration of O3 was observed in winters, followed by summers and monsoon. Similar trends were observed for NO2 and CO. Significant correlation was found for O3 with temperature and solar radiation whereas its correlation with relative humidity was not significant.

Exposure levels and health risk assessment of ambient BTX at urban and rural environments of a terai region of northern India

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 ml/min for 20-24 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 CS2 with occasional agitation and analyzed by GC-FID. The total BTX concentration ranged from 3.4 μg m-3 to 45.4 μg m-3 with mean value 30.95 μg m-3 and median 24.8 μg m-3. The mean concentration of total BTX was maximum during winter (39.3 μg m-3), followed by summer (28.4 μg m-3) and monsoon season (25.1 μg m-3). The mean concentration of BTX at urban site (11.8 μg m-3) was higher than that at rural site (8.8 μg 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 R2 value of 0.96 and 0.49 at urban and rural sites respectively. Higher R2 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.

Roadside BTEX Profiles in the Atmosphere at a Terai Region of Northern India

Transportation has turned into an escalating source that causes severe adverse effects on air quality. Over the last few decades, there has been a dramatic increase in the number of publications on traffic-related volatile organic compounds (VOCs), which indicates that automobiles in urban regions are the dominant source of benzene, toluene, ethylbenzene and xylene, commonly called BTEX. A monitoring program was designed and implemented to characterize roadside levels of BTEX during November, 2014 – February, 2015 at Gorakhpur – a terai belt of north India, on both weekdays and weekends. Samples of the air were collected at two sites namely, Nausad Traffic Junction (NTJ) and Golghar Traffic Junction (GTJ). Besides this, air samples were also collected at different distances (3 m, 10 m, 20 m, 30 m respectively) from the road. BTEX were sampled by SKC activated charcoal tubes and analyzed by GC–FID (Gas ChromatographyFlame Ionization Detector). Total BTEX concentration ranged from 9.8 61.3 μg m-3 at roadside sites, Gorakhpur. The total mean BTEX at Golghar traffic junction (GTJ) and Nausad traffic junction (NTJ) were 36.6 μg m-3 and 18.1 μg m-3 respectively. The concentrations of BTEX were plotted against distance from the road. The coefficient of determination (R2 values) for benzene, toluene, ethylbenzene and xylene were found to be 0.65, 0.98, 0.98 and 0.92 respectively. The average T/B and X/E ratios of both the sites together were 2.3 and 1.2 respectively. The higher traffic volume and traffic congestion on weekdays lead to remarkably higher BTEX levels than those observed on Sunday at both the sites. Toluene was found to be dominant followed by benzene, xylene and ethylbenzene. Appropriate traffic management and vehicle emission control should be applied to reduce the VOC pollution in the city. *Corresponding author: Amit Masih, Assistant Professor, Environmental Research Lab, Department of Chemistry, St. Andrew’s College, Gorakhpur, UP, India; E-mail: amitmasih10@yahoo.com Citation: Masih, A., et al. Roadside BTEX Profiles in the Atmosphere at a Terai Region of Northern India. (2017) J Environ Health Sci 3(2): 17. Roadside BTEX Profiles in the Atmosphere at a Terai Region of Northern India Amit Masih*, Anurag S. Lall and J.K.Lal Received date: March 08, 2017 Accepted date: April 27, 2017 Published date: May 02, 2017 DOI: 10.15436/2378-6841.17.1407 particulate matter (PM), including black carbon (BC), volatile organic compounds (VOCs) and semi-VOCs (e.g. polycyclic aromatic hydrocarbons) (Wang et al., 2009). Large amount of air pollutants are released from the vehicle fleet, especially fine particulate matter (PM2.5, particles with aerodynamic diameter less than 2.5 mm) and a range of toxic gases including volatile organic compounds (VOCs) because emission control measures are not strongly enforced for old vehicles and inadequate inspection allows these old vehicles to remain in use (Oanh et al., 2013). Benzene, toluene, ethylbenzene and xylenes (BTEX) collectively form a group of VOCs that are commonly related to the vehicle emission in urban areas worldwide (Monod et al., 2001; Skov et al., 2001). In urban areas, benzene is mainly airborne and generated by vehicular traffic. Atmospheric reactions of BTEX produce secondary pollutants, which in turn causes