Analisis Logam Berat Cadmium (Cd), Cuprum (Cu), Cromium (Cr), Ferrum (Fe), Nikel (Ni), Zinkum (Zn) pada Sedimen Muara Sungai Asahan di Tanjung Balai dengan Metode Spektrofotometri Serapan Atom (SSA)

Abstract

This study was done in Tanjung Balai waters.Observation were carried out at 3 sampling points,1 station were 3 mils and 2 stations others 4 mils and 5 mils from coastal line. The analysis of heavy metals in sediment is held in North Sumatera University laboratory, sample is dried in the air in 3 days, crushed, sifted, at the oven 105 0C more than 6 hours, taken 1 gram sample, disolved in HNO3 concentrated, is heated until 80 0C more than 30 minutes, cooled down, diluted, then the heavy metals Cd, Cu, Cr, Fe, Ni, Zn are analysed by the SSA machine. The outcomes of analysis showed the rate of each heavy metal as follows : Rate Heavy Metal of Ferrum (Fe): 103,2465 mg/Kg,rate heavy metal of Zinkum(Zn):27,4147 mg/Kg, rate heavy metal of Nicel (Ni) : 4,8358 mg/Kg, rate heavy metal of Cuprum (Cu) : 3,4597 mg/Kg, rate heavy metal of Cadmium(Cd) and Chrom(Cr) undetectable (too small). Rate heavy metal of : Cadmium (Cd), Cuprum (Cu), Chrom (Cr), Ferrum(Fe), Nicel (Ni), Zinc (Zn) have not exceeded threshold grade that has been defined by Reseu National d’Observation 1981 for sediment.

Penelitian dilakukan diperairan Tanjung Balai.Sampel diambil di tiga (3) stasiun, dengan 1 stasiun berjarak 3 mil dan 2 stasiun lainnya berjarak 4 mil dan 5 mil dari garis pantai. Analisis kandungan logam berat pada sedimen dilakukan di laboratorium USU, sampel dikeringkan diudara terbuka 3 hari, digerus, diayak, dioven pada suhu 105 0C ± 6 jam, diambil 1 gram sampel, dilarutkan dalam HNO3 PEKAT, dipanaskan hingga suhu 80 0C ± 30 menit, dinginkan, diencerkan lalu logam berat Cd, Cr, Cu, Fe, Ni, Zn dianalisis dengan mesin SSA. Hasil analisis menunjukkan kadar masing-masing logam berat: Kadar logam berat Besi (Fe) :103,2465mg/Kg, kadar Zinkum(Zn):27,4147 mg/Kg, kadar Nikel(Ni):4,8358 mg/Kg, kadar Kuprum (Cu): 3,4597 mg/Kg dan kadar Kadmium(Cd) dan Khrom(Cr) tidak terdeteksi. Maka dari hasil analisis itu dapat disimpulkan bahwa kadar logam berat : Kadmium (Cd), Cuprum (Cu), Chrom (Cr), Ferrum (Fe), Nikel Ni), Zinkum (Zn) belum melampaui nilai ambang batas yang ditetapkan Reseu National d’Observation 1981 untuk sedimen.