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A simple, quick, inexpensive and easily reproduced thin-layer chromatographic method for the separation and quantitation of organochlorine pesticides and polychlorinated biphenyls (PCB's) was developed using an aluminum oxide plate, which was developed in a triethylamine: hexane solvent, with steam and U.V. treatment for visualization. The recoveries reported are mostly in the range of 90 to 100%. Polychlorinated biphenyls (PCB's) were first noted by Reisborough1 as materials present in wildlife samples that could give rise to interference in analysis of organochlorine pesticides. Of late analysis of PCB's has become as important as analysis of the pesticides. In both groups of materials many individual components exist and separation of the two groups by some method prior to the generally used gas-liquid chromatographic methodology is essential. Early separation methods were based on liquid-solid chromatography on florisil, silicic acid-celite, alumina, silica-gel and charcoal2,3,4,5,6. Careful activation conditions had to be followed and reports on unsuccessful attempts to duplicate work have appeared. Thin-layer chromatographic (TLC) methods have been used to separate these two groups of materials. The bulk of the T.L.C. methods however are only semiquantitative or confirmatory. We wish to describe a thin-layer separation technique that we have developed which separates PCB's and the common organochlorine pesticides. Elution of spots and analysis of the eluants by gas liquid chromatography indicated the method is quantitative. Further studies using untrained personnel indicated that the method is easily reproduced. [ABSTRACT FROM PUBLISHER]

Tissue from a harp seal given methyl mercury at a concentration of 0.25 mg/kg in its diet for 61 days, was highly contaminated with mercury. Over 70% of the mercury in the seal's liver (64.0 p.p.m.) was in the inorganic form indicating a demethylating system in this organ. Most of the mercury in the liver, spleen and kidney of an untreated seal was also in the inorganic form. In contrast, over 75% of the mercury in the adrenals and gonads (14.2 and 13.0 p.p.m., respectively) of the treated seal was methyl mercury. Mercury was not detectable in the gonads and not analyzed in the adrenals of the untreated seal. Biosynthesized (in vitro) cortisol, corticosterone, cortisone, and 11-ketotestosterone were isolated and identified from the adrenal incubations, and delta4-androstene-3,17-dione and testosterone were isolated and identified from ovarian incubations from both untreated and methyl mercury (in vivo) treated seals. The ovaries and adrenals from both seals appeared to be normal under the light microscope. The ovaries from both seals were in the same follicular phase, but in vitro incubations of tissue from these organs indicated that the methyl mercury and treatment caused a marked alteration of steroid biosynthesis in tissue from the treated seal. The altered pattern of steroid biosynthesis was also demonstrated by autoradiography, and it is suggested that this technique could be used as an indicator of incipient contamination by a pollutant.