净化烹饪油污微生物菌种的选育

利用正交试验方法优化了净化烹饪油污菌种选育的环境和营养条件，即：油：20mL、NaNO3（2g/L)：4mL、KH2PO4(0．5g/L)：3mL、微量元素溶液(CuS04-5H200．03g/L，ZnSO4-7H2O0．1g/L，MnCl2-4H2O0．05g／L)：1mL和温度37℃；而且得出氮源是影响菌体增长的最重要因素，温度是影响微生物降解的重要因素，而微量元素和磷源对菌种培育结果影响较小。在此优化条件下选育出了合适降解烹饪油污的c种子菌液，其每天可降解油22mg，L以上，并鉴定出主要的微生物是嗜水性气单孢菌(Aeromonas hydrophila 4AK4)、黄丝藻属(Tribonema)和多甲藻属(Peridinium)等菌体；分析了选育过程活性微生物、目标污染物和微生物的代谢产物三者之间的关系，发现所选微生物能利用油类物质作为碳源进行生长代谢。     

阻燃剂废水的处理及回收利用

采用电化学氧化、电气浮与Fenton强氧化性协同作用的电解Fenton法预处理难降解阻燃剂废水(CODCr=17108mg/L),CODCr去除率达98.34%,色度去除率达74.19%。其适宜操作条件是:pH=2.0～2.6;电流密度10.8～14.3A/dm2;H2O2起始摩尔浓度27～42mmol/L;FeSO4起始质量浓度660～990mg/L;电解5h。处理后取废水50mL,HCl(1∶1)67mL,NaAlO230g,FeCl3·6H2O4g,加热回流反应2h制成聚合氯化铝铁无机高分子絮凝剂(Al2O39.93%、Fe2O30.75%、盐基度68.0%左右)。该絮凝剂在pH=7～9时有良好的絮凝效果。     

产木聚糖酶嗜碱细菌的筛选及产酶条件研究

利用透明圈法筛选到一株产木聚糖酶的嗜碱芽孢杆菌NT 9,该菌株产木聚糖酶为组成型。正交设计实验结果表明 ,合适的产酶条件为 :木糖 15 .0g/L ,硫酸铵 2 .5 g/L ,Tween 80 2 0 g/L ,K2 HPO4 1.0g/L ,MgSO4 ·7H2 O 0 .2g/L ,pH值 10 .0 ,3 7℃ ,2 0 0r/min ,振荡培养 72h。其木聚糖酶活力可达到 6.3 6IU/mL。     

Fenton试剂处理电厂离子交换树脂再生废水

采用 Fenton试剂对电厂离子交换树脂再生废水进行催化氧化处理 ,实验结果表明 ,当溶液 p H=2 .0、H2 O2 ( 30 % )投加量为 6 0 m L/L、F e SO4· 7H2 O投加量为 4.5 g/L、H2 O2 投加次数为 4、反应时间为 1.5 h时 ,废水的处理效果最佳     

超声波/Fenton工艺降解微量邻苯二甲酸二甲酯和壬基酚效能的研究

研究了在超声波、Fenton不同体系中邻苯二甲酸二甲酯(DMP)和壬基酚(NP)的降解效果.通过正交实验得到超声波/Fenton工艺各个因素影响程度的大小为:H2O2投加量＞初始pH＞反应时间＞Fe2+投加量＞超声功率.最后得到降解250mL质量浓度为100 μg/L的DMP的最佳条件:H2 O2投加量为2 mmol/L、Fe2+投加量为0.40 mmol/L、初始pH为3.00、超声功率为1 800W、反应时间为120 min,降解率可达到85.96％;降解250mL质量浓度为100 μg/L的NP的最佳条件:H2O2投加量为4mmol/L、Fe2+投加量为0.50 mmol/L、初始pH为3.00、超声功率为1 800W、反应时间为120 min,降解率可达到78.70％.     

天然沸石负载La2O3-ZnO-TiO2光催化降解活性艳红K-2BP

利用80目天然斜发沸石作载体制备La2O3(0.5%)-ZnO(20%)-TiO2/沸石复合光催化剂,以20 W紫外灯为光源,在自制的光催化反应器中降解活性艳红K-2BP,考察了光照时问、空气通入量、催化剂用最、溶液初始浓度、H2O2与Fe3 投加量等对活性艳红K-2BP光催化降解率的影响.结果表明,当溶液初始浓度为60 mg/L,催化剂投加量为12 g/L,通气量为1 200 mL/min,光照2.5 h,活性艳红K-2BP的降解率可达99.2%;H2O2和Fe3投加量为4 mL/L和3 g/L时,光照1 h活性艳红K-2BP降解率分别为100%和97.2%.紫外-可见吸收光谱显示,LZTZ光催化剂町有效降解印染废水.     

电-Fenton法处理4-氯酚废水

采用电解法对 4 氯酚废水进行了处理。以活性炭纤维 (ACF)为阴极 ,铁为阳极 ,并向阴极不断通入空气 ,电解过程中生成的H2 O2 与阳极溶解的Fe2 + 形成Fenton(芬顿 )试剂 ,Fenton试剂在电解的过程中可以产生大量活性羟基·OH ,能够很好地氧化降解废水中的 4 氯酚。在最佳试验条件下 :室温 ,氯酚浓度为 5 0mg/L ,电解时间为 6 0min ,pH值为4 5 ,电流密度为 15 38A/m2 ,Na2 SO4浓度为 3g/L时 ,4 氯酚去除率为 85 70 %。     

内源过氧化氢（H2O2）对Stenotrophomonas maltophilia DHHJ降解羽毛

过氧化氢为好氧微生物代谢的中间产物。本研究考察了Stenotrophomonas maltophilia DHHJ代谢H2O2规律及体内外过氧化氢对酶降解羽毛的促进作用,该菌与代谢相关酶SOD及CAT随发酵时间延长而增长。H2O2含量随培养时间延长而升高,84 h后可达71μg/mL。该菌也可在低浓度下提高酶对羽毛的降解效率,在含量0.015%,即150μg/mL时,可将降解率从17%提高到25%以上。结果为微生物降解羽毛机理研究提供一条新的线索,同时也可为羽毛生物炼制产业化应用提供新思路。     

对乙酰氨基酚制备过程中废水的处理

采用芬顿法、光催化氧化法与生物降解法相结合,研究对乙酰氨基酚制备过程中高浓度废水的降解。以COD的去除率为指标,研究各种方法的主要因素对废水降解效果的影响,通过控制单因素变量实验,确定各种方法的最佳工艺条件。结果表明,芬顿法的最佳工艺条件:废水的pH为4.0、FeSO4·7H2O加入量为0.10 mol/L、H2O2(30%)加入量为56.5 mL/L、反应时间3 h;光催化氧化降解废水的最佳条件:H2O2(30%)加入量4.5 mL/L,光照时间4 h。生物降解较适宜条件:pH为7.0,温度为28~29℃。在各种方法的最佳条件下,可使废水的COD从18 979.24 mg/L降至36.14 mg/L。     

响应面法和神经网络优化Acinetobacter sp. DNS32发酵基质

为了提高阿特拉津降解菌Acinetobacter sp.DNS32的产量,分别采用响应曲面法和基于人工神经网络的遗传算法对阿特拉津降解菌DNS32发酵培养基中3个重要基质成分(玉米粉、豆饼粉、K2HPO4)进行优化研究。响应曲面法确定3种成分的含量为玉米粉39.494 g/L,豆饼粉25.638 g/L和K2HPO43.265 g/L时,预测发酵活菌最大生物量为7.079×108CFU/mL,实测量为7.194×108CFU/mL;人工神经网络结合遗传算法优化确定3种主要成分含量为玉米粉为39.650 g/L,豆饼粉为25.500 g/L,K2HPO4为2.624 g/L时,预测最大值为7.199×108CFU/mL,实测量为7.244×108CFU/mL;最终确定培养基配方:玉米粉为39.650 g/L,豆饼粉为25.500 g/L,K2HPO4为2.624 g/L,CaCO3为3.000 g/L,MgSO4.7H2O和NaCl均为0.200 g/L;优化后阿特拉津降解菌DNS32发酵生物量比优化前提高了36.6%。结果表明,在阿特拉津降解菌DNS32发酵培养基组分优化方面,响应面法和基于人工神经网络的遗传算法都是可行的,基于人工神经网络的遗传算法具有更好的拟合度和预测准确度。     

Patterns of volatile metabolites and nonvolatile trichothecenes produced by isolates of <Emphasis Type="Italic">Stachybotrys,Fusarium, Trichoderma,Trichothecium</Emphasis> and <Emphasis Type="Italic">Memnoniella</Emphasis>

We reported previously that trichodiene, a volatile trichothecene derivative, was produced by a Stachybotrys isolate, also known to produce highly cytotoxic, non-volatile, macrocyclic trichothecenes (satrotoxins). We investigated the relationship between the production of trichodiene and various non-volatile trichothecenes for several molds. Volatile metabolites were concentrated by adsorption on Tenax TA and analyzed by GC/MS, while non-volatile metabolites were separated by HPLC, derivatized and analyzed by GC/MS. Stachybotrys chartarum isolates producing macrocyclic trichothecenes secreted significantly larger amounts of trichodiene and other sesquiterpenes than isolates which only produced simple trichothecenes. The amounts of secreted trichodiene were relatively small in all cases. With the exception of Memnoniella, which excreted small amounts of sesquiterpenes, the other isolates produced varying amounts of sesquiterpenes, including trichodiene, as well as simple tricothecenes, no detectable trichodiene, but large amounts of griseofulvin derivatives. In Stachybotrys there is apparently a correlation between trichodiene and macrocyclic trichothecene production. In the remaining isolates, there was no simple relationship between trichodiene and non-volatile trichothecene synthesis. Trichodiene is produced in larger amounts by Stachybotrys isolates, which also produce satratoxins, but it will be difficult to utilize this metabolite to detect toxic isolates in buildings due to the relatively small amounts excreted.     

Radionuclides and trace elements in fish collected upstream and downstream of Los Alamos national laboratory and the doses to humans from the consumption of muscle and bone

Abstract

The purpose of this study was to determine radionuclide and trace element concentrations in bottom‐feeding fish (catfish, carp, and suckers) collected from the confluences of some of the major canyons that cross Los Alamos National Laboratory (LANL) lands with the Rio Grande (RG) and the potential radiological doses from the ingestion of these fish. Samples of muscle and bone (and viscera in some cases) were analyzed for ³H, ⁹⁰Sr, ¹³⁷Cs, ^totU, ²³⁸Pu, ^239,240Pu, and ²⁴¹Am and Ag, As, Ba, Be, Cr, Cd, Cu, Hg, Ni, Pb, Sb, Se, and Tl. Most radionuclides, with the exception of ⁹⁰Sr, in the muscle plus bone portions of fish collected from LANL canyons/RG were not significantly (p<0.05) higher from fish collected upstream (San Ildefonso/background) of LANL. Strontium‐90 in fish muscle plus bone tissue significantly (p<0.05) increases in concentration starting from Los Alamos Canyon, the most upstream confluence (fish contained 3.4E‐02 pCi g^‐1 [126E‐02 Bq kg^‐1]), to Frijoles Canyon, the most downstream confluence (fish contained 14E‐02 pCi g^‐1 [518E‐02 Bq kg^‐1]). The differences in ⁹⁰Sr concentrations in fish collected downstream and upstream (background) of LANL, however, were very small. Based on the average concentrations (±2SD) of radionuclides in fish tissue from the four LANL confluences, the committed effective dose equivalent from the ingestion of 46 lb (21 kg) (maximum ingestion rate per person per year) of fish muscle plus bone, after the subtraction of background, was 0.1 ± 0.1 mrem y^‐1 (1.0 ± 1.0 μSv y^‐1), and was far below the International Commission on Radiological Protection (all pathway) permissible dose limit of 100 mrem y^‐1 (1000 μSv y^‐1). Of the trace elements that were found above the limits of detection (Ba, Cu, and Hg) in fish muscle collected from the confluences of canyons that cross LANL and the RG, none were in significantly higher (p<0.05) concentrations than in muscle of fish collected from background locations.     

A History of Dry Cleaners and Sources of Solvent Releases from Dry Cleaning Equipment

Approximately 25, 000-35, 000 dry cleaning facilities currently operate in the U.S. The release of perchloroethylene and other solvents from these establishments represents a major source of soil and groundwater contamination. The manner in which dry cleaning solvents escape from dry cleaning plants is, for all practical purposes, identical for chlorinated and petroleum hydrocarbon solvents and is related to one of the following events: the catastrophic failure of a component of the dry cleaning system, the improper installation, operation or maintenance of the dry cleaning equipment or a combination of all of these causes. Acceptable customs, codes and regulations can also dictate what is authorized for operation of a dry cleaning facility in a particular community, geographic area during a particular time frame. Environmental litigation dealing with the origin of a solvent release from dry cleaners tends to focus on the design and manufacture of dry cleaning industry machines such as washers, washer extractors, tumblers, solvent filters, water separators, stills and spotting boards. A thorough analysis of the daily operations of dry cleaners often reveals that poor maintenance, failure to follow the manufacturer's instructions and the actions of the operator are the most likely causes of soil and groundwater pollution. In order to forensically evaluate the most probable origins of a solvent release and to examine issues regarding liability, a thorough understanding of the history of dry cleaning and a detailed analysis of the operation and maintenance of the dry cleaning equipment are necessary. The discovery of solvent plumes in the vicinity of dry cleaning plants may suggest that the solvent source is the dry cleaning plant; however, the presence of these plumes does not necessarily indicate that the dry cleaning equipment was defectively designed or manufactured. A thorough review of the type of equipment used over the life of the dry cleaning plant and verifiable solvent mileage records frequently indicates that operators of the plant have disposed of solvent and contaminated solids into the municipal sewer or on ground surfaces.     

Radionuclides in deer and elk from Los Alamos national laboratory and the doses to humans from the ingestion of muscle and bone

Abstract

This paper summarizes radionuclide concentrations (³H, ⁹⁰Sr, ¹³⁷Cs, ²³⁸Pu, ^239,240Pu, ²⁴¹Am, and ^totU) in muscle and bone tissue of mule deer (Odocoileus hemionus) and Rocky Mountain elk (Cervus elaphus) collected from Los Alamos National Laboratory (LANL), Los Alamos, New Mexico, lands from 1991 through 1998. Also, the committed effective dose equivalent (CEDE) and the risk of excess cancer fatalities (RECF) to people who ingest muscle and bone from deer and elk collected from LANL lands were estimated. Most radionuclide concentrations in muscle and bone from individual deer (n = 11) and elk (n = 22) collected from LANL lands were either at less than detectable quantities (where the analytical result was smaller than two counting uncertainties) and/or within upper (95%) level background (BG) concentrations. As a group, most radionuclides in muscle and bone of deer and elk from LANL lands were not significantly higher (p<0.10) than in similar tissues from deer (n = 3) and elk (n = 7) collected from BG locations. Also, elk that had been radio collared and tracked for two years and spent an average time of 50% on LANL lands were not significantly different in most radionuclides from road kill elk that have been collected as part of the environmental surveillance program. Overall, the upper (95%) level net CEDEs (the CEDE plus two sigma for each radioisotope minus background) at the most conservative ingestion rate (50 lbs of muscle and 13 lbs of bone) were as follows: deer muscle = 0.22 mrem y^‐1 (2.2 μSv y^‐1), deer bone = 3.8 mrem y^‐1 (38 μSv y^‐1), elk muscle = 0.12 mrem y^‐1 (1.2 μSv y^‐1), and elk bone = 1.7 mrem y^‐1 (17 μSv y^‐1). All CEDEs were far below the International Commission on Radiological Protection guideline of 100 mrem y^‐1 (1000 μSv y^‐1), and the highest muscle plus bone net CEDE corresponded to a RECF of 2E‐06, which is far below the Environmental Protection Agency upper level guideline of 1E‐04.     

Leaching of seven pesticides currently used in cotton crop in Mato Grosso State—Brazil

This study aimed to evaluate the leaching of pesticides and the applicability of the Attenuation Factor (AF) Model to predict their leaching. The leaching of carbofuran, carbendazim, diuron, metolachlor, α and β endosulfan and chlorpyrifos was studied in an Oxisol using a field experiment lysimeter located in Dom Aquino – Mato Grosso. The samples of percolated water were collected by rain event and analyzed. Chemical and physical soil attributes were determined before pesticide application to the plots. The results showed that carbofuran was the pesticide that presented a higher leaching rate in the studied soil, so was the one representing the highest contamination potential. From the total carbofuran applied in the soil surface, around 6 % leached below 50 cm. The other pesticides showed lower mobility in the studied soil. The calculated values to AF were 7.06E-12 (carbendazim), 5.08E-03 (carbofuran), 3.12E-17 (diuron), 6.66E-345 (α-endosulfan), 1.47E-162 (β-endosulfan), 1.50E-06 (metolachlor), 3.51E-155 (chlorpyrifos). AF Model was useful to classify the pesticides' potential for contamination; however, that model underestimated pesticide leaching.     

Endosulfan in China 2—emissions and residues

Background, aim, and scope  Endosulfan is one of the organochlorine pesticides (OCPs) and also a candidate to be included in a group of new persistent organic pollutants (UNEP 2007). The first national endosulfan usage inventories in China with 1/4° longitude by 1/6° latitude resolution has been reported in an accompanying paper. In the second part of the paper, we compiled the gridded historical emissions and soil residues of endosulfan in China from the usage inventories. Based on the residue/emission data, gridded concentrations of endosulfan in Chinese soil and air have been calculated. These inventories will provide valuable data for the further study of endosulfan. Methods  Emission and residue of endosulfan were calculated from endosulfan usage by using a simplified gridded pesticide emission and residue model—SGPERM, which is an integrated modeling system combining mathematical model, database management system, and geographic information system. By using the emission and residue inventories, annual air and soil concentrations of endosulfan in each cell were determined. Results and discussion  Historical gridded emission and residue inventories of α- and β-endosulfan in agricultural soil in China with 1/4° longitude by 1/6° latitude resolution have been created. Total emissions were around 10,800 t, with α-endosulfan at 7,400 t and β-endosulfan at 3,400 t from 1994 to 2004. The highest residues were 140 t for α-endosulfan and 390 t for β-endosulfan, and the lowest residues were 0.7 t for α-endosulfan and 170 t for β-endosulfan in 2004 in Chinese agricultural soil where endosulfan was applied. Based on the emission and residue inventories, concentrations of α- and β-endosulfan in Chinese air and agricultural surface soil were also calculated for each grid cell. We have estimated annual averaged air concentrations and the annual minimum and maximum soil concentrations across China. The real concentrations will be different from season to season. Although our model does not consider the transport of the insecticide in the atmosphere, which could be very important in some areas during some special time, the estimated concentrations of endosulfan in Chinese air and soil derived from the endosulfan emission and residue inventories are in general consistent with the published monitoring data. Conclusions  To our knowledge, this work is the first inventory of this kind for endosulfan published on a national scale. Concentrations of the chemical in Chinese air and agricultural surface soil were calculated for each grid cell. Results show that the estimated concentrations of endosulfan in Chinese air and soil agree reasonably well with the monitoring data in general. Recommendations and perspectives  The gridded endosulfan emission/residue inventories and also the air and soil concentration inventories created in this study will be updated upon availability of new information, including usage and monitoring data. The establishment of these inventories for the OCP is important for both scientific communities and policy makers.     

Impact of spiked concentrations of Cd,Pb, As and Zn in growth medium on elemental uptake of Nasturtium officinale (Watercress)

This study is aimed at investigating the impact of water quality on the uptake and distribution of three non-essential and toxic elements, namely, As, Cd and Pb in the watercress plant to assess for metal toxicity. The plant was hydroponically cultivated under greenhouse conditions, with the growth medium being spiked with varying concentrations of As, Cd and Pb. Plants that were harvested weekly for elemental analysis showed physiological and morphological symptoms of toxicity on exposure to high concentrations of Cd and Pb. Plants exposed to high concentrations of As did not survive and the threshold for As uptake in watercress was established at 5 ppm. Translocation factors were low in all cases as the toxic elements accumulated more in the roots of the plant than the edible leaves. The impact of Zn on the uptake of toxic elements was also evaluated and Zn was found to have an antagonistic effect on uptake of both Cd and Pb with no notable effect on uptake of As. The findings indicate that phytotoxicity or death of the watercress plant would prevent it from being a route of human exposure to high concentrations of As, Cd and Pb in the environment.     

Butyltin compounds in sediment and fish from the Polish Coast of the Baltic Sea

Concentrations of mono- (MBT), di- (DBT), and tri-(TBT) butyltin compounds were measured in eggs, liver, and muscle of nine species of fish from four regions of the Baltic Sea - the Firth of Vistula, the Gulf of Gdańsk, Puck Bay, and the mouth of the Vistula River. The overall concentration ranges among all the fish sampled from the four sites were: < 7 to 79 ng/g for MBT, 6 to 1100 ng/g for DBT, 7 to 3600 ng/g for TBT, and 16 to 4800 ng/g for total BTs, on a wet wt basis. The highest concentration of total BTs was found in herring liver from the Firth of Vistula (4800 ng/g, wet wt) and in roach muscle from Puck Bay (3300 ng/g, wet wt), while the least concentration was found in burbot eggs and liver from the Vistula River (39 and 32 ng/g, wet wt, respectively). TBT was the major form of BTs present in most samples analyzed. Sediment samples collected from shipyards in the Gulf of Gdańsk contained butyltin concentrations ranging from 1.2 to 46 μg/g (dry wt) for MBT, 2.0 to 42 μg/g for DBT, and 2.6 to 40 μg/g for TBT. As with the fish, the majority of the BTs in sediment were present as TBT, which suggested recent exposure of the aquatic environment of the region to TBT.     

Malathion-induced sublethal toxicity on the intestine of cricket frog (Fejervarya limnocharis)

The effect of malathion [diethyl(dimethoxythiophosphorylthio)succinate] at sublethal concentration (0.006 ppm) on intestinal parameters of cricket frog (Fejervarya limnocharis) was studied for 24 hrs to 240 hrs of exposure and remarkable histopathological alterations were observed. The study on intestinal parameters revealed acute pathological conditions in the intestinal wall. The toxic effect became evident as the cytoplasm of the cells disintegrated and the cells became empty and vacuolated. The cell membranes were also ruptured. Degenerative changes of the absorptive surface (villi) of the intestine in the different periods of exposure were pronounced. Severe atrophic nature (necrotic mucosa) of the intestine began from 48 hrs onwards to 96 hrs of exposure.