LIPID-CONTAINING SEMIPERMEABLE-MEMBRANE DEVICES FOR MONITORING ORGANIC CONTAMINANTS IN WATER

A semipermeable membrane device (SPMD) is described for passive in-sit u monitoring of organic contaminants in water. The device consists of a thin film of neutral lipid (molecular mass generally greater-than-or -equal-to 600 Da), such as triolein, enclosed in thin-walled layflat t ubing made of low-density polyethylene or another nonporous polymer. M athematical models are developed for the device and fitted to concentr ation data from 2,2',5,5'-tetrachlorobiphenyl and phenanthrene flow-th rough exposures and dissipation experiments. Model estimates of the av erage concentrations of test chemicals in laboratory exposure water di ffered from the measured concentrations by <2-fold, indicating that it may be feasible to use the device to determine average concentrations of organic contaminants in natural waters.