Figure 7. Correlation of P450RGS performed by WES and by CAS on 10 cleaned NYDMMP sediment extracts

Technical Note DOER-C8

July 1999

Figure 7. Correlation of P450RGS performed by WES and by CAS on 10 cleaned NYDMMP sediment

extracts (WES data are means of six replicates SD; CAS data are means of three replicates

SD)

CONCLUSIONS: The P450RGS and EROD assays are nearly equal in detecting dioxin and

dioxin-like compounds in the sediments, but the P450RGS is the more sensitive of the two assays.

In some cases in which the EROD assay could not detect the presence of dioxin and dioxin-like

compounds in the sample, the P450RGS assay was able to do so. The P450RGS assay also has the

capability of determining the predominance of either PAHs or dioxin/dioxin-like compounds

without using a cleanup step, although more definitive results are obtained by using cleanup. The

nonlabor costs incurred in testing two sediment samples are similar for the two assays, but the

P450RGS is considerably less time-consuming.