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Organochlorines (DDT, toxaphene, PCBs, chlordane, HCHs, dieldrin) were quantified in the blubber of eleven fur seals of the species Arctocephalus pusillus pusillus. The sample clean-up included microwave-assisted extraction (MAE), gel-permeation chromatography (GPC), adsorption chromatography on silica gel and quantitation with GC/ECD. Compounds of technical toxaphene (CTTs) were determined after separation from the PCBs. Highest levels arose for p , p ′-DDE (7–1000 μg/kg). A so far unknown compound labelled Q1 caused the second most abundant peak in the samples. Q1 was identified as a heptachloro compound by GC/MS in the electron capture negative ionisation and electron impact ionisation mode. Levels of Q1 were estimated relative to the ECD response factor of trans -nonachlor. These estimated Q1 levels ranged from 27 to 351 μg/kg being in the range or higher than the levels of PCBs (6–697 μg/kg), toxaphene (10–97 μg/kg), chlordane (3–159 μg/kg), and dieldrin (4–36 μg/kg). One sample which showed significantly higher DDT and PCB levels (but not toxaphene, dieldrin, Q1, and chlordane) than the others is most likely migrated from an area higher polluted with DDT and PCBs. Another one showed very low levels which were not explained. Except these samples, the levels determined in the blubber were among the lower levels reported for this kind of tissue. The data also confirmed that the organochlorine levels in Africa are varying from region to region, and that there is still a need for further research.

Levels of organochlorines (PCBs, DDT, toxaphene, chlordane, hexachlorobenzene (HCB), hexachlo-rocyclohexanes (HCHs), dieldrin, Q1) were determined in eggs of both penguins (Adelie Pygoscelis adeliae, Chinstrap Pygoscelis antarctica, Gentoo Pygoscelis papua) and skuas (South Polar Skua Catharacta maccormicki, Brown Skua Catharacta antarctica lonnbergi, Mixed Pair Skua Catharacta maccormicki x lonnbergi) from the Antarctic. Focused open-vessel microwave-assisted extraction (FOV-MAE) was performed for the extraction of entire, partly lyophilised eggs (approx. 50 g). After gel-permeation chromatography (GPC) and adsorption chromatography on deactivated 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 validated with certified reference material SRM 1588. In general, skua eggs revealed higher organochlorine levels than penguin eggs. Mai...

Objective To determine whether supplementation with the long-chain omega-3 polyunsaturated fatty acids eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) affects behavioral symptoms and cognitive impairments in children 6–12 years of age diagnosed with attention-deficit/hyperactivity disorder (ADHD). Study design The randomized, double-blind placebo-controlled 16 weeks trial was conducted with 95 children diagnosed with ADHD according to DSM-IV criteria. Behavior was assessed by parents, teachers and investigators using standardized rating scales and questionnaires. Further outcome variables were working memory, speed of information processing and various measures of attention. For a subgroup of 81 participants, erythrocyte membrane fatty acid composition was analyzed before and after the intervention. Results Supplementation with the omega-3 fatty acid mix increased EPA and DHA concentrations in erythrocyte membranes and improved working memory function, but had no effect on other cognitive measures and parent- and teacher-rated behavior in the study population. Improved working memory correlated significantly with increased EPA, DHA and decreased AA (arachidonic acid).

A Cl(7) component of technical toxaphene (CTT), previously detected in marine mammals and fish and referred to as "7-1", was isolated from contaminated estuarine sediment using preparative solid-liquid chromatography followed by reversed-phase HPLC. The structure of this compound, elucidated by GC/MS and (1)H NMR, was 2-endo,3-exo,5-endo,6-exo,8,8,10-heptachlorobornane (hereafter referred to as B7-1000). This newly identified CTT eluted in the nonpolar fraction from silica and shares the alternating endo-exo chlorine substitution pattern with other relatively nonpolar, persistent congeners (e.g., B8-1413 and B9-1679). Based on ECNI-MS response, levels of B7-1000 in tissue samples of various higher organisms including humans were as high as 16% of B8-1413. Enantioselective determination of B7-1000 using a modified cyclodextrin chiral stationary phase (beta-BSCD) resulted in enantiomer ratios that were depleted in adipose tissue of a marine bird (skua) and Weddell seal blubber (0.3 and 0.5, respectively), but not in elephant seal blubber (1.1). Elucidation of the structure of B7-1000 thus validates previous predictions of persistence based on structure-activity relationships, chromatographic properties, and molecular modeling.

Dependent on the species, feedstuffs and plants differ considerably in their iodine content. Among the I-poorest feedstuffs there are grain concentrates, extracted soybean and rapeseed oil meals, mixed feed (without I-containing mineral mixture) and grasses. The I content of the plants decreases with proceeding growth. The I intake of ruminants via vegetable feed and drinking water is affected by the distance of the site from the seaside and the geological origin of the soil material. Ruminants get considerably less iodine via feedstuffs and water in the southern territory of the GDR than in the central and northern areas. Therefore, mineral mixtures for cattle and sheep are supplemented with 18 mg KIO3 per kg mixture in the southern districts. The I analysis of 205 charges of mineral mixtures revealed only a mean I content of 7 (3.8-11.3) mg per kg mixture.