Introduction Population growth and industrial development along the coast have greatly influenced pollution loads into coastal ma- rine environment. Land-based activities are major source of pollution in the coastal waters of Indonesia. Based on several studies conducted in coastal areas, heavy metal contamina- tions are among the persistent issues in Indonesia. These heavy metals have potential negative impact on the health of marine living resources and the people who consume seafood products. Fate of metal contaminants in coastal ecosystem can be in the three compartments, seawater, sediments and biota (Fig. 1), and the development of research on this subject fol- lowed ideas that were developed during the last three decades. Metal pollution studies in water and sediments have been conducted by many researchers since early 1980s. Stud- ies of metal pollution based on concentration of metals in solute form can be really challenging especially when avail- ability of instruments and laboratory that meet the state of the art technology is limited. Because metal concentration in seawater is highly fluctuated, it is difficult to make a general trend of metal contaminants in a wide area. Hence, research of metal pollution has been directed to study of metals in sediments since 1990s. The first review of toxic trace metal pollution in sediments provided information on trace metal contamination in several coastal sediments of Indonesia (Arifin 2001). Solid and strategic actions are urgently needed to miti- gate the ever increasing metal contaminants in both biota and Heavy metal contamination in Indonesian coastal marine ecosystems: A historical perspective Zainal ARIFIN 1 , Rahma PUSPITASARI 1 and Nobuyuki MIYAZAKI 2,3 1 Research Centre for Oceanography–LIPI, Jl. Pasir Putih I, Jakarta 14430, Indonesia *E-mail: zainal.arifin@lipi.go.id 2 Ocean Research Institute, The University of Tokyo, 1–15–1 Minamidai, Nakano, Tokyo 164–8639, Japan 3 Present address: Ocean Policy Research Foundation, Kaiyo Senpaku Building, 1–15–16 Toranomon, Minato-ku, Tokyo 105–0001, Japan Received 4 November 2010; Accepted 18 May 2011 Abstract — Toxic heavy metals are one of the widespread environmental contaminants in Indonesian coastal waters. Research and monitoring on heavy metal contaminations have been conducted since 1980. The development of pollution studies may be di- vided into three phases: firstly, monitoring of heavy metal contamination focused on seawater (1979–1990); secondly, research and monitoring focused on biota and sediment (1990–2000); and the third phase, the research focused on bioassay and geochem- istry of heavy metals (2000–present). Most metals have been intensively studied in components of coastal ecosystem. An ele- vated heavy metal contamination has been mostly recorded in the northern coast of Java Island and the eastern coast of Sumatra Island, while coastal waters of Borneo and the Sulawesi Islands are, in general, relatively pristine. The concentration of heavy metals in water and biota is commonly very low. In contrast, heavy metals in sediments are relatively elevated in concentrations especially in areas where land-based activities exist such as industrial activities. Recent research has been directed on metal spe- ciation in sediments and development of bioassay using local species of organisms to reduce uncertainty when local managers have to make a decision on environmental issues related to ecological risk assessment. Key words: heavy metals, coastal waters, sediments, biota, Indonesia Coastal Marine Science 35(1): 227–233, 2012 227 Fig. 1. Fate of metal contaminants in coastal ecosystem (solid arrow) and the development of research during the last three decades (broken arrow).