Combinatorial Biochemical and Chemical Analyses of Polychlorinated Dibenzo- p -dioxins and Dibenzofurans in Agricultural Soils from Chongming Island, Shanghai, China

We compared polychlorinated dibenzo-p-dioxin and dibenzofuran (PCDD/F) concentrations [expressed as toxic equivalent quantities (TEQs)] in agricultural soil samples from Chongming Island (Shanghai, China) determined using two analytical approaches, an enzyme-linked immunoassay (EIA) method and a high resolution gas chromatography–high resolution mass spectrometry (HRGC/HRMS) method. The PCDD/F concentrations in all 31 soil samples were at background levels (7.30–16.7 pg EIA-TEQ/g from the EIA analysis and 0.526–1.99 pg WHO-TEQ/g from the HRGC/HRMS analysis). Although, the EIA method overestimated the PCDD/F concentrations compared with the concentrations determined using the HRGC/HRMS method. The absence of false-negatives showed by the EIA analysis verified that this method is useful for preliminary sample screening (prior to HRGC/HRMS analysis) and the preliminary characterization of potentially contaminated sites.