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61.
We recently reported a system for inactivating antineoplastics in which sodium hypochlorite is supplied by the electrolysis of sodium chloride solution. In this study, we designed an electrolysis apparatus for inactivating the cytotoxicity of antineoplastics in clinical wastewater using the system. The apparatus consists of an electrolysis cell with platinum-iridium electrodes, a pool tank, a circulating system for wastewater, a safety system for explosive gas and overflow, and an exhaust duct. The free chlorine concentration increased linearly up to 6500 mg l(-1), and pH also increased to 9.0-10.0 within 2h, when 0.9% sodium chloride solution was electrolyzed. We examined its efficacy with model and clinical wastewaters. The reciprocal of dilution factor for disappearance of cytotoxicity using Molt-4 cells was compared before and after electrolysis. In the model wastewater, that was 9.10 x 10(4) before electrolysis, and 3.56 x 10(2) after 2h of electrolysis. In the clinical wastewater (n=26), that was 6.90 x 10(3)-1.02 x 10(6) before electrolysis, and 1.08 x 10(2)-1.45 x 10(4) after 2h of electrolysis. Poisonous and explosive gases released by the electrolysis were measured; however, they were found to be negligible in terms of safety. The environmental load was evaluated by carbon dioxide generation as an index and it was found that the carbon dioxide generated by the electrolysis method was 1/70 lower than that by the dilution method with tap water. Moreover, the cost of the electrolysis method was 1/170 lower than that of the dilution method. This method was found to be both effective and economically valuable.  相似文献   
62.
We conducted congener-specific analysis of non-dioxin-like polychlorinated biphenyls (non-dioxin-like PCBs) in blood collected in February 2004 from 127 elderly residents living in Nakagawa Town, Fukuoka Prefecture, Japan. The present study is one of the few studies in which 56 non-dioxin-like PCBs congeners were measured in human blood. Of the 127 elderly residents, 51 were men (mean: 68.1 years) and 76 were women (mean: 68.1 years). Among 197 non-dioxin-like PCB congeners, 56 were identified in the blood of elderly residents. The arithmetic mean total concentrations of 56 non-dioxin-like PCBs congeners in the blood of elderly men and women in Nakagawa Town were 419 (median: 378) and 363 (median: 323)ngg(-1)lipid, respectively, and the concentrations were in the range of 172-1102 and 119-1226ngg(-1)lipid, respectively, indicating that the total concentrations in elderly men are significantly higher than those in elderly women. The contamination of non-dioxin-like PCBs in the blood of elderly men and women in Fukuoka Prefecture was found to have decreased compared to past levels. The ratios of hexachlorinated biphenyls (hexaCBs) to the total concentrations of 56 non-dioxin-like PCBs congeners in the blood of elderly men and women were 44.6% and 45.6%, respectively, which was particularly high compared with those of other congeners. 2,2',4,4',5,5'-HexaCB (#153) among hexaCBs congeners, the most abundant congener in the blood of elderly men and women, contributed approximately 23.0% and 23.5% to the total concentrations of 56 non-dioxin-like PCBs congeners, respectively. Furthermore, 2,2',3,4,4',5'-hexaCB (#138), 2,3,3',4',5,6-hexaCB (#163)/2,3,3',4',5',6-hexaCB (#164), 2,2',3,4,4',5,5'-heptaCB (#180), and 2,2',3,4,4',5,6'-heptaCB (#182)/2,2',3,4',5,5',6-heptaCB (#187) also showed high ratios to the total concentrations of 56 non-dioxin-like PCBs congeners detected in the blood of elderly men and women. A statistical examination of the relationship between the total concentrations of 56 non-dioxin-like PCBs congeners in blood and the age of elderly residents who were over 60 years indicated statistically significant correlations between the total concentrations of these PCBs congeners and the age of elderly women. However, similar correlations were not observed in elderly men. The results of the present study have indicated the current levels of non-dioxin-like PCBs in the blood of elderly men and women in Fukuoka Prefecture, Japan and can be used as baseline data for those over age 60.  相似文献   
63.
Two sets of new diastereomeric 4-nonylphenol (NP) isomers [4-(3,4-dimethylheptan-4-yl)phenol (344NP, NP-J, L) and 4-(3,4-dimethylheptan-3-yl)phenol (343NP, NP-K, P)] were separated from a commercial NP mixture. The mixture of these diastereomers was synthesized at the same time by a single Friedel-Crafts reaction of 3,4-dimethyl-4-heptanol and phenol, and the mixture was separated into individual NPs by HPLC equipped with Hypercarb column. For the first time, in this study the stereostructure-estrogenic activity relationship of NP diastereomers was investigated. The NP isomers (NP-L and NP-P) having the beta-methyl group over the benzene ring were found to be 2-4 times more estrogenic than their diastereomers (NP-J and NP-K). In the case of the other set of diastereomer [4-(3,5-dimethylheptan-3-yl)phenol, (353NP, NP-E, G)] containing gamma-methyl group in the molecule, the gamma-methyl proton signal (delta 0.49) in the more estrogenic isomer (NP-G) also appeared in a higher field than the corresponding methyl signal (delta 0.76) of the less estrogenic isomer (NP-E).  相似文献   
64.
Bottom sediments from Lake Jinzai in southwest Japan were analyzed to determine their chemical compositions and to assess the potential for ecological harm by comparison with sediment quality guidelines. The pollution status of lake sediments was evaluated by employing contamination factor (CF), pollution load index (PLI), and geoaccumulation index (I(geo)), focusing on a suite of elements in lakebed and core sediments. Elevated concentrations of As, Pb, Zn, Cu, TOC, N, and P were present in several layers of the upper core and other surface sediments. The elevated metal concentrations are likely related to the fine-grained nature of the sediments, reducing bottom conditions produced by abundant organic matter, and possibly minor non-point anthropogenic sources. Moreover, correlations between the concentrations of trace metals and organic carbon, nitrogen, phosphorus, and iron, suggest that these elements play a role in controlling abundances. Calculated CF, PLI, and I(geo) indicate that the sediments are strongly polluted with respect to As, moderately to strongly polluted with Zn, and moderately polluted with Pb and Cu. Metal concentrations exceed the New York State Department of Environmental Conservation (NYSDEC) lowest effect level and the Canadian Council of Ministers of the Environment (CCME) interim sediment quality guidelines that indicate moderate impact on aquatic organisms in the study area.  相似文献   
65.
The lead–zinc (Pb–Zn) mine in Kabwe City and the copper–cobalt (Cu–Co) mine in the Copperbelt Province are major mining areas in Zambia. To examine the effects of metal pollution on wildlife, wild black rats (Rattus rattus and Rattus tanezumi) were captured in Kabwe and Chingola (in the Copperbelt Province), and in Lusaka (a noncontaminated site). Wild black rats in Kabwe accumulated significantly higher concentrations of Pb and Cd in various organs than rats from Lusaka. In Chingola, significantly higher concentrations of Cu, Co, Pb, and Cd were accumulated in wild black rats than in rats from Lusaka. These results were in accordance with metal accumulation patterns in soil. From toxicological aspects, concentrations of Pb and Cd in rats were generally low. However, metallothionein-1 (MT-1) and metallothionein-2 (MT-2) mRNA expression levels in wild black rats from Kabwe were significantly higher than those in rats from Lusaka. A generalized linear model (GLM) showed that concentrations of Zn and Cu had positive effects on the MT-1 and MT-2 mRNA expression. These results suggest that wild black rats in Zambian mining sites were exposed to metals that accumulated in their organs, causing biological responses such as MT mRNA induction. GLM indicated that heme oxygenase-1 (HO-1) mRNA expression could be a marker for Cr exposure.  相似文献   
66.
In this study, we focused on water quality in an urban canal and the Mekong River in the city of Can Tho, a central municipality of the Mekong Delta region, southern Vietnam. Water temperature, pH, electrical conductivity, BOD5, CODCr, Na+, Cl?, NH4 +?N, SO4 2??S, NO3 ??N, and NO2 ??N for both canal and river, and tide level of the urban canal, were monitored once per month from May 2010 to April 2012. The urban canal is subject to severe anthropogenic contamination, owing to poor sewage treatment. In general, water quality in the canal exhibited strong tidal variation, poorer at lower tides and better at higher tides. Some anomalies were observed, with degraded water quality under some high-tide conditions. These were associated with flow from the upstream residential area. Therefore, it was concluded that water quality in the urban canal changed with a balance between dilution effects and extent of contaminant supply, both driven by tidal fluctuations in the Mekong River.  相似文献   
67.
Growth and feeding activities of the tintinnid ciliate Favella taraikaensis fed the toxic dinoflagellate Alexandrium tamarense were examined in laboratory experiments. Both growth and ingestion rates of F. taraikaensis as a function of the A. tamarense concentration were fitted to a rectangular hyperbolic equation. The maximum growth and ingestion rates of F. taraikaensis were 1.0 day–1 and 2.8 cells ind. h–1 (carbon specific ingestion rates: 3.5 day–1), respectively, which are both included in the range of previous data reported for Favella spp. feeding on other algae. The gross growth efficiency (GGE) of F. taraikaensis ranged from 0.26 to 0.49 (mean value 0.40) at the concentration of 10–800 cells ml–1, which is within the range of previous data on Favella spp. Also, the growth and ingestion rates and GGE of F. taraikaensis on A. tamarense were not significantly different from the values on another non-toxic dinoflagellate (Heterocapsa triquetra) at two different prey concentrations. This indicates that the toxicity of A. tamarense probably did not influence the feeding and growth activities of F. taraikaensis at concentrations of less than ca. 800 cells ml–1. To evaluate the grazing by F. taraikaensis on A. tamarense blooms in the field, the population dynamics of A. tamarense were simulated based on the growth and ingestion parameters of F. taraikaensis. As a result, the grazing impact by F. taraikaensis was considered to potentially regulate the development of A. tamarense blooms. If the toxicity of A. tamarense does not influence the growth and feeding activities of F. taraikaensis, the occurrence of such grazer plankton are considered to be important for predicting the course of A. tamarense bloom dynamics under natural conditions.Communicated by T. Ikeda, Hakodate  相似文献   
68.
Wastewater from clinical institutions contains a considerable amount of toxic substances. Among the toxic substances, antineoplastics may induce carcinogenesis, teratogenesis, and the emergence of mutant microorganisms in the environment. Although the incineration or chemical treatments of disposed antineoplastics are recommended, a high energy during incineration and a careful quality control during chemical treatment are required. In this study, we determined the conditions for the electrolytic treatment of an antineoplastic, epirubicin hydrochloride (EH), using two platinum electrodes with a constant current of 100 mA. We analyzed the cytotoxicity, mutagenicity and antibacterial activity of electrolyzed EH and compared them with those of unelectrolyzed EH. Nearly 100% cytotoxicity, mutagenicity and antibacterial activity were eliminated and HPLC did not detect an EH molecule, in the case of electrolysis for 6 h. We also examined the biological cytotoxicities of electrolyzed irinotecan hydrochloride, vincristine sulfate, mitomycin C, paclitaxel, methotrexate and cisplatin, and found that 72.1-99.999% toxicity was eliminated by electrolysis under the same conditions. The biological toxicity of a mixture of these drugs was determined to be decreased by approximately 99% by electrolysis under the same conditions.  相似文献   
69.
Concentrations of p,p'-DDE, polychlorinated biphenyl congeners (PCBs), polychlorinated-dibenzo-p-dioxins (PCDDs), -dibenzofurans (PCDFs) and -naphthalenes (PCNs) were measured in bluefin tuna, swordfish, common cormorants, and barn swallows collected from Italy. Average concentrations of PCBs in livers of tuna, swordfish, cormorant, and swallows were 930, 745, 1420 and 1230 ng PCBs g-1, w.w. respectively. p,p'-DDE was found in tuna, swordfish, cormorant, and swallow livers at mean concentrations of 82, 135, 166 and 95 ng DDE g-1, w.w. respectively. PCNs were found in all the samples analyzed, although at concentrations less than those reported for biota from the Baltic Sea. PCBs, particularly, non-ortho coplanar PCBs accounted for 80-90% of the total TEQs in tuna and swordfish. Relative contribution of PCDDs/DFs to TEQs was greater in cormorants and swallows compared to that in fishes. PCDD/DF congeners accounted for up to 80 and 45% of the total TEQs in cormorants and swallows, respectively.  相似文献   
70.
Larvae of marine organisms often need specific resources or environments at settlement, and their success at settlement might be strongly influenced by the abundance and distribution of such specific resources. The larvae of hermit crabs need small shells to settle, so it is thought that the distribution and abundance of small shells influence the settlement pattern of hermit crabs. To investigate the influence of small shell distribution on the settlement of pagurid hermit crab larvae, we conducted a field experiment at an intertidal rocky shore in Hakodate Bay, Japan. From the line-transect sampling in the field, we found that Pagurus middendorffii settled extensively in the offshore side of the intertidal zone while P. nigrofascia settled in the uppermost area of the intertidal zone. Small shells were most abundant in a narrow shallow trough, slightly offshore from the uppermost area of the intertidal zone. For both species, settler abundance was high where adults were abundant, but settler abundance did not appear to be related to shells abundance. An experiment to clarify settlement patterns showed that larval recruits tended to be similar to those in the line-transect sampling of settlers. Thus shells may not be a primary factor affecting settlement patterns at relatively large scale within the intertidal flat. However, when we analyzed the relationship of settlers and shells separately within each transect, the distribution of settlers was well explained by shell resource availability. Therefore on a smaller scale, shell availability may influence the number of settlers. Settlement periods of P. middendorffii and P. nigrofascia fully overlapped, so their larvae probably were affected by similar transport factors, such as current and tidal movement. Nevertheless they showed different spatial patterns of settlement.Communicated by T. Ikeda, Hakodate  相似文献   
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