Total Volatile Organic Compounds (TVOCs) in Indoor and Outdoor Urban Atmospheres at a Terai Region of Northern India

Volatile organic compounds (VOCs) are an important class of air pollutants and even at a trace amounts; these compounds have a high potential hazard to human health due to their carcinogenic nature. In particular, highly reactive VOCs, which are reported to be toxic and also may participate in numerous reactions in the atmosphere to form secondary air pollutants including ground level ozone and secondary organic fine particles. Thus, an investigation of indoor/outdoor TVOC was conducted at selected locations in Gorakhpur in order to ascertain the contamination levels. The concentrations of TVOC were measured at two locations in the city of Gorakhpur, which covers residential and roadside areas. The samples were collected for the period of three consecutive days for indoors and outdoors, at each microenvironment. TVOC levels were measured using a portable data logging Ion Science PhoCheck+ photo-ionization detector (PID). TVOC concentration for combined indoor/outdoor air was 65.03 ppb and 161.08 ppb at residential and roadside site respectively. At residential site, the indoor and outdoor mean concentration of TVOC was 90.45 ppb and 39.62 ppb respectively. The average indoor concentration at roadside site was 173.52 ppb whereas at outdoor it was 148.68 ppb. At both the sites, the indoor TVOC levels were higher than that at outdoors.