Trace Organic Pollutants in Soil Samples

The contents of target compounds in the soil samples were determined by the isotope dilution method. The detection limits for PCBs, PCNs, and PCDD/Fs were 0.11–0.79, 0.03–0.20, and 0.24–0.61 pg/g, respectively. The recovery ranges for ¹³C-labelled PCBs, PCNs, and PCDD/Fs were 49–80%, 51–82%, and 47–104%, respectively, which met the requirements for the determination of trace organic pollutants in environmental media [13 ,14 ]. A blank sample was analyzed for each batch of six to seven soil samples and treated in the same way as the soil samples. In the blank samples, some PCB and PCN congeners with low levels of chlorination were detected, but their contents were all less than 5% of those in the samples. Therefore, the soil samples were not blank corrected.