A study of the volatile organic compound emissions at the stacks of laboratory fume hoods in a university campus

Abstract

Volatile organic compounds (VOCs) are potentially harmful air pollutants that are commonly encountered in urban environments. Various chemicals known to produce VOCs are used in laboratory fume hoods; however little research has been done to show the effect of such chemicals and associated VOCs on the local air quality. This study aims to assess the concentration of various VOCs emitted from the exhaust stacks of rooftop fume hoods mounted on laboratory buildings, as well as to determine factors that contribute to different concentrations of commonly encountered VOCs. A total of six university campus buildings, comprising four laboratory buildings and two non-laboratory buildings as controls, were selected as case studies. VOCs were sampled using activated charcoal tubes in front of fume hood exhausts located on the rooftops of buildings and were analyzed GC/FID. Factors such as meteorological conditions and the amount of chemicals utilized in the building of interest were investigated. A total of 11 individual compounds were quantified in the samples collected. The concentrations of 11 VOCs at laboratory buildings were significantly higher (GM; 184.74 mu g/m(3), GSD; 3.38) than those of non-laboratory buildings (GM; 12.1 mu g/m(3,) GSD; 1.64, p < 0.001). The concentrations of 10 individual compounds emitted from laboratory buildings were significantly higher than those emitted from non-laboratory buildings (p < 0.001) with the exception of m- and p-xylene (p = 0.155). We found that the amount of chemical use was the predominant factor determining the composition and concentrations of VOCs found (p < 0.001). From this study, we suggest that installation of an air purification system in fume hood ventilation systems is necessary to prevent atmospheric pollution and adverse health effects in university populations, as well as supporting efforts towards creating 'green campus' environments. (C) 2013 Elsevier Ltd. All rights reserved.