Cadmium accumulation on coastal surficial sediments from Yaeyama Islands, Okinawa

Abstract

Cadmium (Cd) of coastal surficial sediments from four islands (25 sites) in the Yaeyama region, Okinawa, was examined for an initial assessment of Cd pollution. Sediment samples sieved through a 63-μm mesh were leached by 0.5 N hydrochloric acid, and extracted Cd was determined using a flameless atomic absorption spectrophotometer. The concentrations of Cd analyzed from the study sites were in the range of 0.017 to 0.316 μg/g. Generally, Cd contamination in the study region has not been particularly remarkable; however, high concentrations were observed near the mouths of rivers that run through agricultural fields and in harbors, suggesting Cd pollution sources, such as phosphate fertilizer and sewage sludge, attributed to anthropogenic activity.