Bull. Environ. Contam. Toxicol. (1994) 53:618-626 9 1994 Springer-Verlag New York Inc. i Snvironrnental Contamination and Toxicology Hydrocarbons in Seawater and Sediment from the West Coast of Peninsular Malaysia A. R. Abdullah, N. M. Tahir, L. K. Wei Department of Chemistry, University of Malaya, 59100Kuala Lumpur, Malaysia Received: 8 September 1993/Accepted: 1 March 1994 The Straits of Malacca, along the west coast of Peninsular Malaysia, is one of the busiest waterways in the world with about 2000 vessels passing through it per month, of which about 25 percent are oil tankers of varying sizes (Daud 1984). In the course of their passage, the practices of tanker ballasting and pumping of bilges by non-tanker vessels result in considerable pollution in these waters. Collisions and groundings also cause oil spills in Malaysian waters. Oil contaminants not only pollute the high seas but also affects the near-coastal waters. Marine oil pollution, in particular that of near-coastal waters, may also be attributed to land-based activities such as the utilisation of petroleum related products, the direct discharge of untreated municipal and industrial wastes containing refined and partly weathered oils to sewers and rivers, and the discharge of effluents from refineries and other similar sources. There is, at present, little information available on the total hydrocarbon concentrations (THCs) in water and sediments in these waters. The present study was undertaken to determine the levels of hydrocarbons in water and sediments along the near-coastal areas of the Straits of Malacca. MATERIALS AND METHODS The locations of the sampling sites are shown in Figure 1. Sampling took place between the months of April 1992 and November 1992. Water samples were collected from a depth of 1 metre using glass Winchester bottles held in a stainless-steel frame and operated by handline. The analysis of THC in water was carried out in accordance with established procedures ( Keizer and Gordon 1973; Parsons et al. 1984). Briefly, water samples were extracted twice with dichloromethane, the extracts combined, and then dried over anhydrous sodium sulphate. Non- petrogenic polar materials were removed using a silica gel column. Correspondence to. A. R. Abdullah 618