Microplastic contamination in coastal sediments along the northern Cirebon coast, West Java, Indonesia: A preliminary assessment

Microplastic pollution in coastal sediments is a growing concern in tropical Southeast Asia, yet published data for the north coast of West Java remain scarce. This study reports a preliminary survey of microplastic occurrence in surface sediments (0 to 5 cm) at four sites along the northern Cirebon coast, West Java, Indonesia: Kejawanan, Mundu, Gebang and Losari. One composite sample per site was processed by saturated NaCl density separation, filtration and stereomicroscopic examination. Forty-five suspected microplastic particles were recovered from 297.59 g of dry sediment, giving site abundances of 125 to 178 particles per kg dry weight (site mean 152), highest at Losari and lowest at Kejawanan. Fibres dominated the assemblage (29 particles, 64.4 per cent), followed by fragments (11), films (4) and a single pellet. Twenty particles measured below 1 mm, and no colour category was dominant. Because polymer identity was not confirmed spectroscopically, no blanks were processed, and the pooled count is only 45 particles, these values are upper bound estimates rather than verified concentrations, and no ecological risk classification is assigned. The fibre share is the result most exposed to airborne contamination, and two particles separate the highest and lowest sites, so the spread is not read as a gradient. Values fall below those reported for beach sediments elsewhere in Cirebon and for estuarine sediments in Surabaya and Jakarta Bay, most plausibly reflecting methodological heterogeneity. The results give a provisional reference point and identify the steps still required: spectroscopic confirmation, blank correction, larger processed masses and replication.