Measurements and PCA/APCS Analyses of Volatile Organic Compounds in Kaohsiung Municipal Sewer Systems, Southern Taiwan

Abstract

This study measured 71 volatile organic compounds (VOCs) collected using stainless steel canisters at 15 monitoring sites in two main Kaohsiung municipal sewers, A-Sewer and B-Sewer, during winter and summer periods in 2008 and 2009. The results indicate that the overall average of total VOCs, TVOC, in A-Sewer was 1173.51 ± 187.69 μg/m3, which was about 40% higher than that in B-Sewer (689.22 ± 151.64 μg/m3). However, TVOC in the winter/dry season was about three (or five) times that in the summer/wet season for A-Sewer (or B-Sewer). For the A-Sewer, chlorinated organics, aromatics, and alkanes were predominant, and altogether contributed to about 90.0% of the TVOC in winter and about 70.6% in summer, with alkenes, ethers, ketones, and sulfur compounds as minor components. For B-sewer, aromatics, alkanes, and chlorinated organics were predominant, and altogether contributed to about 94.1% of the TVOC in winter and about 74.3% in summer, while others were minor ones. The principal component analysis (PCA) and absolute component scores (APCS) models indicate that the percentage source contributions for A-Sewer were solvent usage (31.65 ± 11.27%), oil refineries and storage leaks (28.71 ± 11.52%), auto paintings (19.14 ± 9.74%), asphalt plants (17.05 ± 8.73%), and others (3.45 ± 3.95%). The percentage source contributions for B-Sewer were printing factories (45.35 ± 9.19%), oil refineries and storage leaks (31.78 ± 8.59%), solvent usage (18.64 ± 8.50%), and dry cleaning (4.23 ± 4.70%).