(357c) Use of Ldpe Passive Samplers for Monitoring PAHs in the Water Column of a Suburban, Freshwater Oil-Spill Site

Polycyclic aromatic hydrocarbons (PAHs) are common components of petroleum products that are sometimes released to surface and ground water via leaks and spills, often threatening water quality and ecosystem health. Contaminants that dissolve into water are most readily available for biological uptake and exposure, and can be monitored using passive sampling techniques. This study used low-density polyethylene (LDPE) polymer sampling strips deployed for a period of four weeks in the riverine environment of a Grafton, MA canal that is heavily contaminated by Bunker-C heating oil. The PAHs that were sorbed by the LDPE from the aqueous phase were measured using gas chromatography-mass spectrometry (GC-MS). To permit calibration of the method, involving corrections for possible bio-fouling and differences in compound sampling rates, equilibrium dynamics were established using the loss of deuterated PAH reference compounds impregnated in the LDPE prior to deployment. Results using the LDPE samplers suggest that PAH concentrations previously determined by water grab-samples may overestimate the equilibrium water content of PAHs of concern. Results suggest the value of use of passive samplers in oil-spill contaminated sites, as an alternative to simple water grab samples.