SCREENING ASSAY FOR DIOXIN-LIKE COMPOUNDS BASED ON COMPETITIVE-BINDING TO THE MURINE HEPATIC AH RECEPTOR .2. APPLICATION TO ENVIRONMENTAL-SAMPLES

A series of environmental samples, comprising fly ash, caustic wash wa ter from regeneration of a petrochemical reforming catalyst,fish homog enates, soil, and pulp mill sludge, were analyzed for dioxin-like comp ounds by an assay involving competitive binding of a reference radioli gand and an extract from the sample to mouse hepatic Ah receptor; the results were compared with GC/MS. The bioassay generally gave higher T EQ values than GC/MS, further analysis by GC/MS in most cases identifi ed much of the additional Ah receptor-active material as coplanar PCBs and PAHs.