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Number of results: 5
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Abstract

In 1979- 1981 at the King George Island samples of adipose tissue of 5 pinniped species (L. carcinophagus, L. weddelli, H. leptonyx, M. leonina and A. gazella) were collected and the contents of chlorinated hydrocarbons (CHs) were determined with the gas chromatography method. The highest values were recorded in the leopard seal (432.3 -614.7 ppb DDT), the second highest values in the mature elephant seal (73.4 ppb DDT) and the third in the Weddell seal (54.4 — 69.1 ppb DDT). In the Weddell seal the highest level of HCH content (23.3 — 32.1 ppb) was recorded. A decrease in the content of pp'DDE in the adipose tissue of crabeater seal in successive years was recorded, the values being 36.8 ppb in 1979, 24.4 ppb in 1980 and 15.3 ppb in 1981, as well as an increase in the concentration of HCH (15.3 ppb in 1980 and 27.4 ppb in 1981). The contents of CHs in the adipose tissue of Antarctic pinnipeds are 100—1000 times lower than those in the Arctic seals.
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Abstract

In the region of Bransfield Strait and southern part of Drake Passage the highest amounts of chlorinated hydrocarbons (CHs — compounds of the DDT group, HCH isomers and PCBs) were found in the samples taken at the sampling station where the CHs bottom deposits were released to the upper layers due to the special hydrological situation at this station. Increased amounts of CHs were observed also in phytoplankton sampled close to the melting ice of glacier origin which was considered as a source of pollution. However, phytoplankton sampled from the waters covered with pack-ice exhibited the lowest rate of CHs accumulation. Slightly elevated CHs accumulation was found in sea ice diatoms. All the samples exhibited elevated amount of polichlorinated biphenyls, markedly higher than that of chloroorganic insecticides.
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Abstract

The objective of the paper is to use life cycle assessment to compare environmental impact of different technologies used in the process of water disinfection. Two scenarios are developed for water disinfection life cycle at ZUW Raba water treatment plant: (1) historical, in which gaseous chlorine is used as a disinfectant and (2) actual, in which UV radiation and electrolytically generated sodium hypochlorite are used for that purpose. Primary data is supplemented with ecoinvent 3 database records. Environmental impact is assessed by IMPACT2002+ method and its midpoint and endpoint indicators that are calculated with the use of SimaPro 8.4 software. The focus of the assessment is on selected life cycle phases: disinfection process itself and the water distribution process that follows. The assessment uses the data on flows and emissions streams as observed in the Raba plant. As the results of primal analysis show, a change of disinfectant results in quantitative changes in THMs and free chlorine in water supplied to the water supply network. The results of analysis confirm the higher potential of THMs formation and higher environmental impact of the combined method of UV/NaClO disinfection in distribution phase and in whole life cycle, mainly due to the increase of human toxicity factors. However, during the disinfection phase, gaseous chlorine use is more harmful for environment. But the final conclusion states that water quality indicators are not significant in the context of LCA, while both disinfection and distribution phases are concerned.
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Abstract

Polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT) and its metabolite, dichlorodiphenyldichloroethylene (DDE) can disturb the secretory function of the ovary and both contractions and secretory function of the uterus during the estrus cycle and pregnancy. Additionally, PCBs can pass through the placental barrier into allantoic and amniotic fluid. The presence of PCBs in these fluids is associated with higher frequency of spontaneous abortions and premature births in humans and animals. Therefore, the effect of PCBs, DDT and DDE on the connexins (Cx26, Cx32 and Cx43) and keratin 8 (KRT8) expression in bovine placentomes was investigated. The placentome slices from the second trimester of pregnancy were incubated with PCB153, 126, 77, DDT and DDE (each at doses of 1, 10 or 100 ng/ml) for 48 h. Then, the slices were stained using immunohistochemistry. The density of Cxs staining was measured with Axio- Vision Rel. 4.8 software in fetal-maternal connections and binuclear cells (BNC). None of the tested xenobiotics (XBs) affected the localization of Cxs and KRT8 in the fetal-maternal connection area, but the XBs affected the density of Cxs in fetal-maternal connections and binuclear cells (BNCs). Depend on the doses, in fetal-maternal connections all used PCBs changed the protein expression of different Cxs, while in BNCs, all tested XBs except DDT increased the expression of Cxs. None of investigated XBs affected on KRT8 expression. In summary, used XBs affect the expression of Cxs and change the quantitative relationships between them. Therefore, XBs can unfavorably influence function of the utero-placental barrier in cows.
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Abstract

Influence exerted by various concentrations (0.01 to 50 ppm) of some chlorinated hydrocarbons (Aroclor 1254, Aroclor 1242, pp'DDE, pp'DDT and Lindane (ɣ НСН)) upon the photosynthetic assimilation of 14C02 in Antarctic marine diatom assemblage dominated by Corethron criophilum and some species of Nitzschia (Fragilariopsis group) has been investigated. The photosynthesis was fully inhibited by Lindane (ɣ HCH) in all applied concentrations To smaller extent the photosynthetic process was inhibited in turn by Aroclor 1242, pp'DDE and pp'DDT successively. Aroclor 1254 proved to be the least toxic. The possibility of the decrease of the primary production of the Antarctic diatoms caused by the chlorinated hydrocarbons was discussed.
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