TCC＆TCS对废水处理中生物相的急性毒性试验

研究了TCC(3,4,4′-Trichlorocarbanilde)、TCS(2,2,4′-Trichloro-2′-hydroxydiphenyl)对废水生物处理中的原生动物的急性毒性作用。结果表明:TCC对原生动物的48h半数致死浓度LC_(50)为25000μg/L,TCS48hLC_(50)为23000μg/L,TCC＆ TCS浓度与原生动物的半数致死时间LT_(50)呈明显的负相关;TCC ＆ TCS对原生动物的最大无作用浓度分别为15mg/L和11mg/L,这提示污染源排放的废水到达曝气池时TCC ＆ TCS的含量应低于15mg/L和11mg/L。     

The use of bioluminescent biotests for study of natural and laboratory aquatic ecosystems

A set of bioluminescent tests was developed to monitor water quality in natural and laboratory ecosystems. It consisted of four bioluminescent systems: luminous bacteria, coupled enzyme system NADH:FMN-oxidoreductase-luciferase and triplet enzyme systems with alcohol dehydrogenase and trypsin. The set of biotests was applied for a small forest pond (Siberia, Russia), laboratory microecosystems polluted with benzoquinone and a batch culture of blue-green algae. Thereby effects of natural water compared to those of models of heavy pollution and “bloom” of blue-greens on the bioluminescent tests were revealed. The set of biotests was not affected by a natural seasonal variability of water quality in the unpolluted pond, but responded to the heavy pollution and the “bloom” of blue-greens. The set of biotests could be recommended as the alarm test to control the acute toxicity of natural water bodies.     

Mechanism of concentration addition toxicity: they are different for nonpolar narcotic chemicals, polar narcotic chemicals and reactive chemicals

According to the toxicity mechanism of the individual chemicals, the concentration addition toxicity mechanism is revealed for nonpolar-narcotic-chemical mixtures, polar-narcotic-chemical mixtures and reactive-chemical mixtures, respectively. For nonpolar-narcotic-chemical mixtures, the partitioning of individual chemicals from water to biophase was determined, and the result shows that their concentration additive effect results from no competitive partitioning among individual chemicals. For polar-narcotic-chemical mixtures, their toxicity are contributed by two factors (the total baseline toxicity and the hydrogen bond donor activity of individual chemicals), and it is the concentration additive effect for either of these two factors that leads to their concentration addition toxicity. In addition, the interactions between the reactive chemicals and the biological macromolecules are discussed thoroughly. The results suggest that the net effect of these interactions is zero, and it is this zero net effect that leads to the concentration addition toxicity mechanism for reactive-chemical mixtures.     

铬渣水泥固化及固化体浸出毒性的研究

铬渣水泥固化时要加入硫酸亚铁和添加剂矿渣、粉煤灰 ,硫酸亚铁可以部分地把六价铬还原为三价铬 ,能把得到的固化体六价铬浸出毒性降到低于国家标准 ,抗压强度可达 30MPa以上 ,可综合利用。与此同时 ,本文考虑日晒、振荡时间和固化体粒度对浸出毒性的影响以及固化体表面浸出率、模拟酸雨淋溶对固化体性能的影响。     

Melting and incineration plants of municipal waste. Chemical and biochemical diagnosis of thermal processing samples (emission,residues)

Control of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) in emissions and thermal residues from incinerators has been a cause of public concern for more than one decade. Recently, several studies showed that other persistent organic pollutants (POPs) such as coplanar polychlorinated biphenyls (co-PCBs) also have dioxin-like activity and are released from incinerators. Therefore, the present study was aimed at making a risk assessment about dioxin-like activity in extracts of thermal waste residues (e.g. combustion gas; fly ash, slag) from incineration and melting processes in Germany and Japan. For this purpose, polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs), coplanar polychlorinated biphenyls (co-PCBs), polychlorinated naphthalenes (PCNs) and polyaromatic hydrocarbons (PAHs) were analyzed by chemical analysis. Additionally, 2, 3, 7, 8-TCDD equivalents (EROD-TEQs) were determined by in vitro Micro-EROD bioassay using rat H4IIE hepatoma cells. EROD-TEQs could be correlated to I-TEQ values (from PCDD/Fs/co-PCBs) analyzed by chemical analysis resulting in a maximal sixfold higher estimate. Our study indicates minor influences of co-PCBs, PAHs and PCNs to the sum of dioxin-like toxicity in the extracts of thermal waste residues as determined here. Furthermore, we showed that the levels of dioxins and co-PCBs contained in slag from melting processes and bottom ashes from incineration processes were lower by 1-2 orders of magnitude than that in fly ash.     

Influence of water hardness on the bioavailability and toxicity of linear alkylbenzene sulphonate (LAS)

In the present work, the influence of Ca²⁺ concentration on the toxicity of single cut linear alkylbenzene sulfonate (LAS) homologues was studied. Precipitation boundary diagrams for each homologue were obtained, indicating turbid and clear zones depending on the LAS and Ca²⁺ concentrations. The separation between transparent and turbid zones is given by the so-called precipitation line. LAS toxicity to Daphnia magna was determined at concentrations close to this precipitation line. It was observed that when Ca(LAS)₂ precipitation progresses, LAS bioavailability decreases for test animals, and the toxicity diminishes even at high nominal LAS concentrations. According to the “free ion activity model” (FIAM), the toxicity of a given chemical compound is mainly due to the ionic species (Ca²⁺–LAS⁻) and not due to the precipitated molecule, Ca(LAS)₂. The significance of the present study is in connection with the assessment of LAS sorption/precipitation studies in soils and sediments, where in situ toxicity is strongly influenced by Ca²⁺/Mg²⁺ ions, according to the results presented in this work.     

用水生生物对重金属污染土壤进行生态毒理评价

应用斜生栅藻（Scenedesmus obliquus）和明亮发光杆菌T3（Photobacterium phosphoreum）急性毒性实验方法对重金属污染土壤的进行生态毒理评价，结果表明，斜生栅藻的生长繁殖率和发光菌的相对发光度与土壤中的重金属含量明显相关，并且随重金属投加量的增加，其生长繁殖率和发光度逐渐降低。对3种测试参数进行比较可知，斜生栅藻细胞数增长率是最敏感的土壤毒性检测指标。土壤的毒性在复合污染的条件下比在单一污染的条件下高很多。本研究的结果可以为污染土壤的优先修复提供理论依据。     

Uptake and Modeling of Pesticides by Roots and Shoots of Parrotfeather (Myriophyllum aquaticum) (5 pp)

Intention, Goal, Scope, Background Aquatic plants have a great potential to function as in situ, on-site biosinks and biofilters of pollutants. They are used for phytoremediation and phytotoxicity studies. Pesticide uptake studies are very important to predict contaminant accumulation, translocation, and transformation. There are a lot of models which have been developed for emergent plants, but there are not any existing models for submerged aquatic plants for assessing pesticide uptake. Objective In this study, uptake of selected pesticides in parrotfeather (Myriophyllum aquaticum) were studied and the results were modeled with the aid of Log Kow and the concentration of pesticides. At the end, the developed model was compared to other existing models. Methods The test was conducted with parrotfeather as a model plant. The bioassay and cultivation of this plant were examined. Pesticide uptake by roots and shoots was determined using 14C-radiolabeled materials. Results and Discussion The results were fitted with an equation that showed a relationship between uptake and lipophilicity of pesticides. The model was compared with other pesticide uptake models developed for other plants. Atrazine and cycloxidim were taken up more by roots than by shoots in comparison to other pesticides used. The total uptake, both in shoots and roots, was lower than for terbutryn and trifluralin. The best appropriate model was developed from the results against the other models seen in the literature. The concentration factors (Root Concentration Factor (RCF) and Submerged Shoot Concentration Factor (SSCF)) increased with a higher Kow of the substances. The Submerged Shoot Concentration Factor (SSCF) revealed a better relationship of the chemicals than did the Root Concentration Factor (RCF). Conclusions In this study, an uptake model was developed for rooted, submerged aquatic plants. Further studies are necessary to develop and compare models with different plants and pesticides. Recommendation and Outlook Such studies as this one may be extended to other environmental pollutants in the aquatic ecosystem and may be employed to evaluate the possibility of using different plants in phytoremediation studies.     

Effects of atrazine on acetylcholinesterase activity in midges (Chironomus tentans) exposed to organophosphorus insecticides

Acetylcholinesterase activity was determined for midge larvae (Chironomus tentans) exposed to either organophosphorus insecticides (OPs) alone or OP insecticides in binary combination with atrazine (200 μg/l). Although atrazine by itself did not reduce the level of acetylcholinesterase activity, atrazine in combination with chlorpyrifos significantly decreased acetylcholinesterase activity as compared to chlorpyrifos only treatments. Although similar trends existed for malathion and methyl parathion, differences were not statistically significant. These results match previously published toxicity data where atrazine, although not acutely toxic even at much higher levels, decreased EC₅₀ values for chlorpyrifos by a magnitude of 4, decreased methyl parathion values by a magnitude of 2, and did not decrease values for malathion.     

山苍籽油抗霉作用研究

用减压蒸馏法从山苍籽［Litseacubeba（Lour）Per］提取天然植物精油．以熏蒸和喷洒等方式进行对档案资料、图书的防霉实验．结果表明山苍籽油具有显著的防霉功效，防霉的广谱性和高效性优于目前市售产品．该植物精油对纤维素和少量半纤维素、木质素纸张耐折度．抗老化及字迹颜色坚牢度试验．表明对纸张和字迹无显著影响；毒理分析表明属于安全低毒抗霉剂