Modeling the fate of microplastics in the Sengkarang Estuary, Pekalongan City, Central Java, Indonesia

AbstractPlastic‐containing waste generated from industrial and household activities is usually discharged into rivers. Pekalongan Regency has several rivers that flow into the Java Sea, one of which is the Sengkarang River. Microplastic is a serious pollutant that has prompted enhanced research and experimentation. This study aims to determine the concentration and distribution of microplastics in water and sediment at the mouth of the Sengkarang River, Pekalongan. A total of 10 water samples and five sediment samples were collected from the river body to the deep water area around the Sengkarang River. Modeling of microplastic distribution is made using hydrodynamic modeling and particle tracking models using two‐dimensional mathematical model. The results showed that the abundance of microplastics ranged from 131 to 360 particle/m3 in water samples and 552.5–972.5 particle/kg in sediment samples. The most common types of microplastics found were fibers and fragments. The greatest abundance and distribution of microplastics are found in coastal areas in water samples and mangrove areas in sediment samples. The distribution of microplastics is influenced by tidal currents, wind directions, and also river water discharge.