Evidence on behaviour of low concentration DDT in laboratory sorption experiments

In an investigation of ¹⁴C labelled DDT interaction with suspended marine particulate matter, some difficulties in using blank systems occurred due to differences in adsorption by walls of vessels. Great differences were noted for adsorption of DDT onto walls of containers when comparing systems in the presence and absence of suspended particulate matter.The most acceptable results of an investigation for the distribution of DDT between liquid phase and suspended matter were obtained where both the amount of solute adsorbed on suspended matter and the equilibrium concentration in the liquid phase were measured. Where measurements of adsorbed solute on the solid phase were impossible (for instance in kinetics investigations) more realistic results were obtained if the solute was only measured in the liquid phase disregarding blanks.