The Dutch PCB/Dioxin Study. Development of a method for the determination of dioxins, planar and other PCBs in human...

A method for the determination of dioxins, planar PCBs and other PCBs in human milk is described. The work is part of a big Dutch project, (seven institutes participates) in which 400 human milk samples from two areas (Rotterdam and Groningen) taken at two different times (10 and 42 days) after delivery had to be analysed for planar PCBs, dioxins and other PCBs (1st sampling) and only other PCBs (2nd sampling). Planar compounds are determined with GC/HRMS, other PCBs with GC/ECD. As type of analytes for 1st and 2nd sampling are different the method was focussed on these analytes. After fat extraction, clean up was carried out on GPC and alumina columns. Only in case of analysis of planar compounds and other PCBs, chromatography on porous graphitised carbon was carried out after which GC-HRMS (planar compounds) and GC/ECD (other PCBs) was performed; otherwise GC/ECD after alumina clean up was performed. The method is validated through recovery experiments with standards (other PCBs, labelled planar compounds), comparison of results for other PCBs obtained with the two different clean-up procedures, reproducibility of "quality control samples" for planar compounds blanc chemicals.