Environmental Monitoring and Assessment (2005) 100: 217–234 c  Springer 2005 ALIPHATIC AND POLYCYCLIC AROMATIC HYDROCARBONS IN SEDIMENTS OF KAOHSIUNG HARBOUR AND ADJACENT COAST, TAIWAN CHON-LIN LEE ∗ , MING-TSUEN HSIEH and MENG-DER FANG Department of Marine Environmental and Engineering, National Sun Yat-sen University, Kaohsiung, Taiwan, ROC ( ∗ author for correspondence, e-mail: linnohc@mail.nsysu.edu.tw) (Received 18 June 2003; accepted 2 December 2003) Abstract. Surficial sediment samples collected from Kaohsiung Harbour and its nearby coast were analyzed for aliphatic hydrocarbons and parent polycyclic aromatic hydrocarbons (PAHs). According to our results, the average total concentrations of n-alkanes (n-C 12 to C 35 ) and aromatics (15 PAHs) were 4.33 µgg −1 dry weight (ranged 0.46–22.60) and 0.59 µgg −1 dry weight (ranged 0.09–1.75), respectively. The highest concentrations of aliphatic and aromatic hydrocarbons were recorded in stations near the estuaries of Qianzhen River and Love River, respectively. Aliphatic hydrocarbons in the samples indicate that there has been significant non-petrogenic, possibly terrestrial, contribution in the sediment of the open coast of Kaohsiung Harbour and that there has been dominant contribution from petrogenic sources in the sediment of the inner harbour. PAHs, detected in the samples, however, indicated a higher pyrolytic contribution in open-coast samples and a higher petrogenic contribution in the inner harbour. Overall, sediment concentrations of total alkanes in this study were comparable to those found in Victoria Harbour, Hong Kong and are higher than those found in Xiamen Harbour, China. Concentrations of total PAHs in inner Kaohsiung Harbour sediments were relatively lower than those found in Victoria Harbour, Hong Kong and Xiamen Harbour, China, but comparable to those found in Hsin-ta Harbour, Taiwan and Incheon Harbour, Korea. In comparison with several effect-based sediment quality guidelines, most PAH concentrations found in samples taken from inner harbour stations exceeded the Threshold Effect Level of Florida indicating a slight possibility of adverse effects. Keywords: aliphatic hydrocarbons, Kaohsiung Harbour, oil pollution, PAHs, sediment 1. Introduction Aliphatic hydrocarbons (AHCs) and polycyclic aromatic hydrocarbons (PAHs) are two major classes of compounds that have attracted most investigations of petroleum related hydrocarbons (Benlahcen et al., 1997; Guzzella and Paolis, 1994). They en- ter the marine environment from various sources. Accidental oil spills, although most newsworthy, are not the only sources of those compounds in the marine envi- ronment. AHCs can be of both petrogenic and biogenic origin, while PAHs can be petrogenic, pyrolytic and biogenic. Both AHCs and PAHs are often used to iden- tify hydrocarbon sources. The level of PAHs in the ecosystem, in particular, has received some attention because they potentially have carcinogenic and estrogenic