Aquatic Pollution and Coastal Management

Unit 4 : Pesticide pollution

4.5.Comparison of behavioral toxicity of chlorinated hydrocarbons(CLHCs) and related compounds
The ultimate fate of these pollutants including partitioning into various aquatic environmental compartments (water, suspended solids, sediments and biota) will depend on a number of factors including concentration, dilution, water solubility, biogeochemical processes taking place, adsorption to soils, suspended particulates and sediments, lipohilicity and bioaccumulation in living organisms.

The hydrophobic nature of CLHCs makes their presence in water to be at ultra-trace level (ng/l) and their accurate determination difficult. The adsorption of these compounds to particulate matter and sediments is an important mechanism for their removal from the water column. Consequently, the sediment component of aquatic ecosystems can be the ultimate sink of CLHCs similar to metals and petroleum hydrocarbons, and suspended particulates entering slow moving waters such as larger water bodies settle out and their associated CLHCs are added to the existing sediments component.