波罗的海灰海豹（Halichoerus grypus）和环斑海豹（Phoca hispida botnica）的肾损害

波罗的海中的灰海豹和环斑海豹种群在60～70年代期间发生严重减少的现象。成年动物曾显示出（目前仍显示出）一系列损害现象，特别是雌性动物的生殖器官、肠、皮肤、肾、肾上腺以及颅骨（波罗的海海豹综合症）等的损害。本报告提供了1977～1996年期间在波罗的海本体和波的尼亚湾收集的76只灰海豹和29只环斑海豹肾脏光学显微病变的形态和盛行情况。血管小球的特殊变化是毛细血管壁的弥散性变厚以及毛细血管壁或被膜壁中存在大而圆的透明体。远曲小管和集合管的特殊变化包括通过多层细胞增殖使正常上皮发生病灶性置换。这些病变的盛行及程度与年龄有关，因此也就是与接触环境毒物的时间长短有关。肾损害在波罗的海灰海豹身上比在环斑海豹身上明显。在来自瑞典动物园的5只灰海豹身上也记录下了类似的发现。这些动物在其生命的大部分时间内都是以波罗的海中的鱼类为食的。在5只波罗的海灰海豹和动物园灰海豹中的其中一只身上进行了显微镜检测。主要是根据一只波罗的海灰海豹身上的发现进行电子显微镜检的结果包括肾小球毛细血管壁的肾小球膜间位以及肾单位远基部位细胞增殖中居间细胞的特征。来自苏格兰海岸的11只灰海豹和来自斯瓦尔巴群岛23只环斑海豹被作为参照物。这些参考海豹没有一只显示出有上述的特殊损害现象。作者认为，波罗的海环境中的有机氯污染是造成这些肾脏病变的一个因素。     

Abnormal karyotype in the chorion,not confirmed in a subsequently aborted fetus

An abnormal fetal karyotype, containing a del 16(q21-qter) as an extra chromosome, was diagnosed in all 14 metaphases examined in a sample of chorionic villous biopsy material. After elective abortion a mosaicism for this cell-line together with a normal one was detected in the chorionic tissue. Fibroblast cultures from several fetal skin biopsies all revealed a normal karyotype.     

Partitioning behavior of polychlorinated biphenyls

Partitioning of polychlorinated biphenyls (PCBs) among several idealized environmental compartments was investigated using equilibrium conditions. Simulations with single equilibrations suggested that PCB mixtures do not weather significantly. However, simulations with multiple equilibrations of a selected phase with renewed phases suggested that PCB mixtures have the potential to weather. These simulations were strongly influenced by temperature; both the compositions and total amount of the PCBs in each phase at equilibrium changed significantly with temperature. These simulations lend support to the hypothesis that lower and higher chlorinated PCBs behave differently in the environment.     

On the perchlorination of 2-hydroxybiphenyl and 2-(2,4-dichlorophenoxy)-4,5,6-trichlorophenol and their methyl ethers

2-Hydroxybiphenyl and 2-(2,4-dichlorophenoxy)-4,5,6-trichlorophenol and their methyl ethers were perchlorinated with four different reagents of various strengths. It was shown that perchlorination is not a reliable method in the analysis of these compounds. Pure octachlorodibenzofuran and nonachlorohydroxybiphenyl were, however, synthesized by the perchlorination procedure.     

Polybrominated diphenyl ethers and traditional organochlorine pollutants in fulmars (Fulmarus glacialis) from the Faroe Islands

The observed high-level burdens of organohalogens among the residents of the Faroe Islands, needs to be explained. Long-finned pilot whale (Globicephala melas) blubber and meat are known sources of environmental exposure. The present study focus on the organohalogen contamination of the fulmar (Fulmarus glacialis). The compounds quantified in fulmar muscle, fat, and egg are PCBs, DDTs, hexachlorobenzene (HCB), and polybrominated diphenyl ethers (PBDEs). The dominating pollutants are the 4,4'-DDT metabolite 4,4'-DDE and the two PCB congeners, CB-153 and CB-180, which are present in geometric mean concentrations of 7100, 4700 and 2500 ng/g lipid weight (l.w.), respectively, in adult fulmar muscle. 4,4'-DDT and HCB concentrations are approximately 250 ng/gl.w., each. Concentrations in the eggs are about 50% of the fulmar muscle levels, due to differences in lipid amounts, 4% in muscle and 10% in the eggs, the exposure contribution on a fresh weight basis is almost the same. As a result, both the egg and the adult fulmar muscle may lead to a significant exposure risk, if consumed by humans. BDE-153, the most abundant PBDE congener in fulmar muscle, with a geometric mean concentration of 6.5 ng/gl.w., is much lower than the individual PCB congeners and 4,4'-DDE concentrations. In the adult fulmar muscle, the relative PBDE congener pattern is different from that previously observed in biota, with BDE-153 and BDE-154 as the dominating congeners, rather than BDE-47. In contrast, BDE-47 is the most abundant congener in juvenile muscle and subcutaneous fat. The summation operatorPBDE concentrations are almost the same in egg, muscle (adult and juvenile) and subcutaneous fat (juvenile). For the polybrominated biphenyl (BB-153) the concentrations are considerably higher in the adult bird and egg than in the juvenile bird; this is also seen for the PCB and 4,4'-DDE concentrations. PCB concentrations found in fulmar egg and muscle are in the same range as seen in the pilot whale, i.e. 590-5700 ng/gl.w. for CB-153. Hence humans are also exposed to PCBs at a reasonable degree via intake of fulmar and/or fulmar egg and not only via pilot whale blubber.     

Algal tests with soil suspensions and elutriates: a comparative evaluation for PAH-contaminated soils

An algal growth inhibition test procedure with soil suspensions is proposed and evaluated for PAH-contaminated soil. The growth rate reduction of the standard freshwater green alga Pseudokirchneriella subcapitata (formerly known as Selenastrum capricornutum) was used as the toxicity endpoint, and was quantified by measuring the fluorescence of solvent-extracted algal pigments. No growth rate reduction was detected for soil contents up to 20 g/l testing five non-contaminated Danish soils. Comparative testing with PAH-contaminated soil elutriates and soil suspensions showed that the suspensions had toxicity endpoints 2.5-3000 times lower than tests with the corresponding elutriates. Algal growth inhibition tests with soil suspensions are recommended for screening purposes as a supplement to elutriate testing. Experiments with a phenanthrene-spiked soil, showed that the sorbed compound did not contribute to the toxicity. However, the soil did act as a reservoir for phenanthrene, allowing desorption to occur continuously during the algal test which maintained higher concentrations of phenanthrene in the dissolved phase. Phenanthrene-spiked soil incubated for 90 days before algal testing, resulted in a reduction of the toxicity to P. subcapitata by a factor of 76 (from EC10 = 0.3 to 23.6 g soil/l). However, during this 90-day period the total concentration of phenanthrene in the soil decreased by 38% (from 322 to 199 mg/kg) indicating that phenanthrene in the aged soil had become less bioavailable.     

<Emphasis Type="Italic">Drosophila melanogaster</Emphasis> virgins are more likely to mate with strangers than familiar flies

Recent evidence shows that females of many species can discriminate against males and/or male phenotypes they have mated with previously. However, these studies have not tested whether actual mating is necessary to induce the avoidance behaviour. A preference for strangers may have evolved because it avoids multiple matings with similar genotypes. Alternatively, there may be selection against mating with familiar individuals directly. By choosing its first mate among unfamiliar individuals (which are less likely close relatives than are those encountered early in life), a virgin might disentangle some of the potential benefits of avoiding genetic incompatibility and inbreeding in the offspring from the costs of remating. In this study, we test whether Drosophila melanogaster flies bias their mate choice towards strangers according to previous, non-copulatory, experience. Based on 173 trials over 12 weeks, virgin females presented with two virgin males were 59% more likely to mate with a novel male than the one which she had been housed with for 8 h the day before. Hence we present the first report showing that a dipteran can distinguish between previously encountered and not previously encountered conspecifics.