Kandungan Logam Berat Merkuri pada Ikan Tuna (Yellowfin dan Bigeye) dan Tuna-Like (Swordfish) Hasil Tangkapan dari Samudera Hindia dan Samudera Pasifik

AbstrakKomoditi tuna dan tuna-like merupakan hasil perikanan yang memiliki nilai ekonomis bagi Indonesia. Namun, logam berat dapat terakumulasi di biota ini karena posisinya sebagai top predator.  Penelitian ini menganalisis 895 data sekunder hasil pengujian merkuri yellowfin tuna (Thunnus albacares), bigeye tuna (Thunnus obesus) dan swordfish (Xiphias gladius), yang merupakan data official control oleh Badan Karantina, Pengendalian Mutu dan Keamanan Hasil Perikanan (BKIPM). Tujuan penelitian adalah untuk menganalisis kandungan merkuri yellowfin tuna, bigeye tuna dan swordfish, serta korelasinya dengan berat ikan dan menganalisis data kontaminan merkuri yellowfin tuna, bigeye tuna dan swordfish terkait pencemaran habitat perairan asal bahan baku di Samudera Hindia dan Samudera Pasifik. Metode analisis menggunakan regresi linier dan analisis t-test. Pengujian merkuri menggunakan Atomic Absorption Spectrophotometric (AAS). Hasil analisis menunjukkan bahwa kandungan merkuri sangat bervariasi antar jenis, berat dan asal perairan. Dua jenis tuna dari kedua perairan mengandung merkuri <1,0 mg/kg, kandungan merkuri yellowfin tuna berkisar antara 0,06±0,06 mg/kg hingga 0,33±0,18 mg/kg, sedangkan bigeye tuna antara 0,05±0,02 mg/kg hingga 0,33±0,14 mg/kg. Berat kedua ikan tidak berkorelasi terhadap kandungan merkuri, namun pada bigeye tuna terdapat perbedaan konsentrasi merkuri yang signifikan antara kelompok berat 1-10 kg/ekor dengan ukuran yang lebih besar (>100 kg/ekor). Sebaliknya pada swordfish, kandungan merkuri meningkat dengan penambahan berat ikan, yang berkisar antara 0,08±0,01 mg/kg hingga 1,61±0,02 mg/kg. Terdapat 34% (>50 kg) swordfish dari Samudera Hindia yang kandungan merkuri nya melebihi batas 1,0 mg/kg. Kandungan merkuri tuna dan tuna-like hasil tangkapan di Samudera Hindia lebih tinggi dibandingkan Samudera Pasifik dan berbeda nyata, sehingga dapat mengindikasikan Samudera Hindia lebih tercemar merkuri. Study on Mercury Concentrations in Tuna (Yellowfin and Bigeye) and Tuna-like (swordfish) Caught from Indian and Pacific OceansAbstractTuna and tuna-like species are considered as highly economic fish species for Indonesia. However, as a high-tropic level predatory species, tuna may accumulate heavy metal contaminants. This study analyzed 895 secondary data of mercury levels in tuna and tuna-like species, based on official control conducted by Badan Karantina Ikan, Pengendalian Mutu dan Keamanan Hasil Perikanan (BKIPM). The objectives of this study were to analyze correlations between mercury contents in yellowfin, bigeye and swordfish with fish weight and fish habitats (Indian and Pacific Oceans). Mercury was analyzed using Atomic Absorption Spectrophotometric (AAS). The data was analyzed based on linear regression and t-test. The result found that mercury concentrations varied significantly among species, weight and fish habitats. Two tuna species from two habitats, have mercury concentration of <1.0 mg/kg. Mercury in yellowfin ranged from 0.06±0.06 mg/kg to 0.33±0.18 mg/kg, while in bigeye it ranged from 0.05±0.02 mg/kg to 0.33±0.14 mg/kg. For yellowfin and bigeye, mercury concentrations were weakly associated with fish weight, except in bigeye, there was a significant difference of mercury concentration between the fish at the group of 1-10 kg with the larger size (>100 kg). In contrast, a strong relationship between mercury content with fish weight was observed in swordfish, where mercury concentration increased with increasing fish weight. It ranged from 0.08±0.01 mg/kg to 1.60±0.02 mg/kg, and 34% of swordfish caught from the Indian Ocean (>50 kg of weight) have mercury content that exceeded 1.0 mg/kg. Mercury concentration of tuna and tuna-like caught from the Indian Ocean were significantly higher than those caught from the Pacific Ocean, which could indicate that the Indian Ocean was more polluted interm of mercury than the Pacific Ocean.