Microplastic Pollution in the Inlet and Outlet Networks of Rawa Jombor Reservoir: Accumulation in Aquatic Fauna, Interactions with Heavy Metals, and Health Risk Assessment

RITA RAHMAYANTI, Dr. rer. nat Andhika Puspito Nugroho, S.Si., M.Si.

2021 | Tesis | MAGISTER BIOLOGI

Aliran sungai dianggap sebagai jalur penyebaran mikroplastik dari daratan ke berbagai sistem perairan. Pencemaran sungai yang terhubung dengan Waduk Rawa Jombor dapat meningkatkan konsentrasi mikroplastik di waduk. Air yang keluar dari reservoir akan membawa mikroplastik yang menyebar ke jaringan sungai di sekitar reservoir. Logam berat memiliki afinitas yang tinggi terhadap mikroplastik sehingga meningkatkan beban logam pada permukaan mikroplastik. Transfer mikroplastik di sepanjang rantai makanan mengarah pada kemungkinan peningkatan efek buruk pada organisme, terutama predator puncak. Penelitian ini bertujuan untuk mengevaluasi akumulasi dan karakterisasi mikroplastik di perairan, sedimen, dan fauna perairan (zooplankton, benthos, dan ikan); interaksi dengan logam berat (Pb, Cu, Cd, dan Zn); dan penilaian risiko kesehatan. Mikroplastik dikumpulkan dari enam lokasi pengambilan sampel. Kepadatan, jenis polimer, dan warna mikroplastik dianalisis, serta konsentrasi logam berat pada permukaan mikroplastik dan penilaian risiko kesehatan. Hasil penelitian menunjukkan kontaminasi mikroplastik pada tingkat sedang. Akumulasi mikroplastik pada fauna akuatik menunjukkan pola yang sama dengan mikroplastik di lingkungan. Konsentrasi mikroplastik pada fauna akuatik menunjukkan peningkatan melalui transfer trofik dan indikasi biomagnifikasi. Logam berat teradsorpsi pada permukaan mikroplastik dalam konsentrasi tinggi. Berdasarkan penilaian risiko kesehatan, kontaminasi mikroplastik pada ikan di inlet dan outlet Waduk Rawa Jombor masih aman, namun perlu pemantauan lebih lanjut karena kemungkinan bahaya kesehatan jangka panjang yang mungkin timbul.

Streams are regarded as a pathway for spreading microplastics from land to various aquatic systems. The contamination of streams connected to the Rawa Jombor Reservoir may increase microplastic concentrations in the reservoir. The water coming out of the reservoir will carries microplastics that spread out into the stream networks around the reservoir. Heavy metals have a high affinity for microplastics, increasing metal burdens on the surface of microplastics. The transfer of microplastics along the food chain leads to the possibility of increased adverse effects on organisms, mainly top predators. This research aims to evaluate the accumulation and characterization of microplastics in water, sediment, and aquatic fauna (zooplankton, benthos, and fish); interactions with heavy metals (Pb, Cu, Cd, and Zn); and health risk assessment. Microplastics were collected from six sampling locations. The density, type of polymers, and color of microplastics were analyzed, as well as heavy metal concentrations on the surface of microplastics and a health risk assessment. The results showed microplastic contamination at a moderate level. The accumulation of microplastics in aquatic fauna showed the same pattern as microplastics in the environment. Microplastic concentrations in aquatic fauna showed an increase through trophic transfer and indications of biomagnification. Heavy metals were adsorbed on the surface of microplastics in high concentrations. Based on the health risk assessment, microplastic contamination of fish at the inlet and outlet of the Rawa Jombor Reservoir is still safe, but further monitoring is needed because of the possible long-term health hazards that may arise.

Kata Kunci : microplastics, aquatic fauna, metal adsorption, health risk assessment