Uptake of chlorohydrocarbons from soil by lipid-containing semipermeable membrane devices (SPMDs)

Chlorohydrocarbons (CHCs) were surveyed in contaminated lake shore soil in Central Finland with polyethylene membranes containing synthetic triolein (SPMDs). High levels of hexachlorobenzene (HCBz) and PCBs were found in a significant number of the SPMDs exposed 28 days to 35 soil sampling locations along the 350 meter long shoreline. Distributions of HCBz and PCBs were different as demonstrated by two maximas of HCBz and four maximas of PCBs observed. Soil was also analyzed at selected locations for concentrations of CHCs, organic carbon (OC) and moisture. Steady state environmental fate modeling and simple equilibrium partition estimates based on analytical results both gave the same steady state concentrations in SPMD lipid for HCBz and PCB congeners. This indicates that HCBz and PCB concentrations in soil did not change significantly during the 28 day exposure. Uptake rates from soil to SPMD lipid were estimated and found not to correlate with moisture or OC. Approximation of the total contamination at the bulk shore soil gave 4.2 kg for HCBz and 3.4 kg for sum of PCBs.