OCCURRENCE, DISTRIBUTION AND BIOACCUMULATION BEHAVIOUR OF HYDROPHOBIC ORGANIC CONTAMINANTS IN AN URBAN WATERSHED IN SINGAPORE

Abstract

Emerging organic contaminants (EOCs) are gaining more attentions due to their relatively high production volume and environmental concentrations currently. In this research, occurrence, fate and partitioning behaviour in water-sediments-biota system of EOCs have been fully investigated and compared with the well understood hydrophobic organic compounds (HOCs), such as organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs). EOCs exhibited high levels in water, while legacy POPs were observed at high concentrations in sediments and biota, exceeding guidelines in some cases. In the section of bioaccumulation, we found that the bioaccumulation potential generally correlated to the hydrophobicity. Finally, a bioaccumulation model was carried out to predict the bioaccumulation potential of the HOCs in this urban freshwater catchment. The present study provides fundamental information to help assess exposure risks and potential impacts to ecological and human health.