Cadmium concentration in water and sediment from lake Lau Kawar, North Sumatra

Abstract

Heavy metals are easy to bind organic matter and settle to the bottom of the waters and unite with sediments, which is cadmium. Cadmium (Cd) is found from volcanic eruptions, from various human activities, and is carcinogenic. This study aims to analyze the concentration of cadmium in water and sediment in Lake Lau Kawar. Water samples were collected by purposive sampling at three stations using Horizontal Bottle samples. Sediment samples were collected compositely using an Eckmann grab then analyzed by the Atomic Absorption Spectrophotometer method. Descriptive data analysis used comparative quantitative methods, namely comparing the level of cadmium in water and sediment in Lau Kawar Lake with the quality standards set by WHO and IADC/CEDA. The water quality in Lake Lau Kawar is in good condition. The concentration of heavy metal Cd in water and sediment still meets the established water quality standard criteria. The source of Cd contamination in the lake, which comes from the volcanic ash of Mount Sinabung, is only carried in low quantities. The largest source of contamination comes from the activities of residents as fertilizers and pesticides used on agricultural land.