Kandungan Logam Berat Pb dan Cd dalam Sedimen di Pantai Trimulyo dan Pantai Tirang, Semarang

Abstract

Kandungan timbal (Pb) dan kadmium (Cd) di sedimen sebagian berasal dari limbah industri yang masuk ke perairan dan terakumulasi di muara sungai. Pantai Trimulyo berada di pesisir Semarang, dekat dengan Kawasan Industri Terboyo yang berpotensi membuang limbah logam berat ke peraian. Pantai Tirang juga berpotensi tercemar limbah logam berat dari industri di Kecamatan Tugu yang masuk ke aliran Sungai Tapak. Penelitian ini bertujuan untuk mengetahui kandungan logam Pb dan Cd pada sedimen di Pantai Trimulyo dan Pantai Tirang. Penelitian dilakukan dengan metode survei eksploratif dan penentuan lokasi pengamatan dengan metode purposive sampling. Sampel sedimen diambil sebanyak 3 kali pengulangan disetiap lokasi dengan sediment core. Sampel sedimen dianalisis di Laboratorium BBTPPI Semarang menggunakan alat Atomic Absorption Spectrophotometer (AAS) untuk menentukan kadar logam Pb dan Cd dalam sedimen. Hasil analisis kandungan logam Pb dalam sedimen menunjukkan bahwa konsentrasi logam berat tertinggi ditemukan di Pantai Tirang sebesar 49,16 mg/kg dan Pantai Trimulyo memiliki kandungan Pb tertinggi 23,78 mg/kg. Hasil analisis kandungan logam Cd dalam sedimen di Pantai Trimulyo dan Pantai Tirang sebesar >0,050 mg/kg. Pengukuran parameter lingkungan (suhu, salinitas, pH, DO, kecepatan arus dan kecerahan perairan) secara in situ menunjukkan konstribusi terhadap kandungan logam berat pada sedimen. Secara keseluruhan, kandungan logam berat Cd pada sedimen di setiap lokasi penelitian tidak melebihi baku mutu, sedangkan kandungan logam berat pada sedimen yang melebihi atau mendekati baku mutu yaitu logam berat timbal.

The sediments contain lead (Pb) and cadmium (Cd) from industrial waste were often found to enter nearby waters and accumulates at river mouths. Trimulyo Beach is adjacent to the Terboyo Industrial Estate on Semarang's coast, which has the potential to dump heavy metal waste into the waters. Heavy metal waste from industry in Tugu District that enters the Tapak River might also pollute Tirang Beach. The aim of the study is to determine the Pb and Cd content of sediments at Trimulyo and Tirang beaches. The research was conducted by using an exploratory survey method, and the research site was determined using a purposive sampling method. Using the sediment core, sediment samples were taken three times in each location. The levels of Pb and Cd metals in sediment samples were analysed using an Atomic Absorption Spectrophotometer (AAS) at the Semarang BBTPPI Laboratory. The analysis of the metal content of Pb in the sediment showed that Tirang Beach had the highest concentration of heavy metal at 49.16 mg/kg, and Trimulyo Beach had the highest Pb content at 23.78 mg/kg. The results showed that the Cd metal content in sediments at Trimulyo Beach and Tirang Beach was >0.050 mg/kg. Environmental parameters measured in situ (temperature, salinity, pH, DO, current velocity, and water clarity) made a contribution to the heavy metal content in the sediment. Overall, the heavy metal content of Cd in the sediment at each research location did not exceed the quality standard, while the lead heavy metal exceeded or approached the quality standard.