Determination of organochlorine levels in Antarctic skua and penguin eggs by application of combined focused open-vessel microwave-assisted extraction, gel-permeation chromatography, adsorption chromatography, and GC/ECD

Levels of organochlorines (PCBs, DDT, toxaphene, chlordane, hexachlorobenze ne (HCB), hexachlorocyclohexanes (HCHs), dieldrin, Q1) were determined in e ggs of both penguins (Adelie Pygoscelis adeliae, Chinstrap Pygoscelis antar ctica, Gentoo Pygoscelis papua) and skuas (South Polar Skua Catharacta macc ormicki, Brown Skua Catharacta antarctica lonnbergi, Mixed Pair Skua Cathar acta maccormicki x lonnbergi) from the Antarctic. Focused open-vessel microwave-assisted extraction (FOV-MAE) was performed f or the extraction of entire, partly lyophilised eggs (approx. 50 g). After gel-permeation chromatography(GPC) and adsorption chromatography on deactiv ated silica gel, the quantitation was performed by GC/ECD on two capillary columns of different polarity. Compounds of technical toxaphene (CTTs) were determined after separation of the PCBs. The sample clean-up method was va lidated with certified reference material SRM 1588. In general, skua eggs revealed higher organochlorine levels than penguin eg gs. Main contaminants in skua eggs were p,p'-DDE, PCB 153, and PCB 180 with levels about 10 - 350 mu g/kg wet weight without shell (ww). Eggs of pengu ins were topped by levers of hexachlorobenzene (HCB) and p,pl-DDE (2 - 22 m u g/kg ww), respectively. In skua eggs, the most abundant CTTs were B9-1679 (Parlar #50) > B8-1413 (Parlar #26) > B9-1025 (Parlar #62) > B8-1412, the levels were about 1-20 mu g/kg ww. In penguin eggs, however, the order was B8-1413 (Parlar #26)> B9-1679 (Parlar #50) > B8-1412 > B9-1025 (Parlar #62) , and the levels ranged from 0.02 - 0.8 mu g/kg ww. A so far unknown heptac hloro compound labelled Q1 caused an abundant peak in some samples. Levels of Q1 (2 - 126 mu g/kg ww in skua eggs and 0.3 - 1.2 mu g/kg ww without she ll in penguin eggs) were estimated relative to the ECD response factor of t rans-nonachlor.