曝气生物滤池处理印染废水二级出水试验研究

考察了曝气生物滤池（BAF）对经水解、接触氧化二级处理的印染废水进行深度处理的效果，结果表明，针对达到二级标准的生化处理出水，BAF水力负荷为0．9—1．6m／h，气水比（2～3）：1时，COD去除率稳定在50％左右，出水可达到一级排放标准（COD≤100mg／L）。     

天然色素生产废水的生物处理研究

天然色素生产废水是一种色度大、难处理的高浓度有机废水，为了寻找该废水的有效处理方法，本文作者采用由升流式厌氧污泥床（UASB）、生物接触氧化、混凝吸附组成的废水处理工艺，对该废水进行了处理试验，结果表明，对稀释4倍的原水，当进水COD为14900mg／L左右时，UASB经过36h的水力停留时间，COD的去除率为58．2％～60．2％、出水色度为180～270倍，SS为119～126mg／L，pH值为6．5～6．8；UASB出水经过24h好氧生物接触氧化反应，COD的去除率超过90％，SS〈70mg／L；最终经过Ca（CIO）2氧化和煤渣吸附深度处理，脱色可至无色，出水COD为200mg／L以下。UASB-生物接触氧化-氧化吸附组合处理工艺处理该类天然色素生产废水是可行的。     

加热酸化-Fenton氧化处理乳化液废水

采用加热酸化-Fenton氧化处理乳化液废水，在加酸量为1．0mL98％H2SO4／100mL乳化液、加热温度95℃、加热时间1h条件下，初始COD〉20万mg／L，浊度〉8000NTU的乳化液COD降低到46592mg／L，浊度降低到20NTU，加热和酸化的联合过程达到了良好的破乳效果；破乳后的出水在ρ（Fe2＋）／ρ（H2O2）=1：30、ρ（H2O2）和（COD）=1．4、pH=4的条件下进行Fenton氧化，处理后的出水COD可降到18600mg／L，去除率达61．4％，其B／C可由破乳后的0．11提高到0．43，废水的可生化性大大提高，为后续处理创造了可能。     

O3氧化工艺处理黄连素制药废水研究

采用臭氧（O3）氧化法处理含高浓度黄连素和COD的制药废水，探讨了废水初始pH、O3投加量及初始黄连素浓度等因素对O3氧化过程的影响，确定了O3氧化技术处理黄连素制药废水的最佳操作条件。结果表明，O3能够有效分解废水中的黄连素，降低其COD浓度；黄连素浓度为700mg／L、COD为3500mg／L、pH为0．88的废水，进气O3浓度为14．05mg／（L·min），处理时间为180rain（即投加量为2529mg／L）时，黄连素和COD的降解率分别可达77．46％和41．28％，BOD，／COD比（B／C比）从0．06提高到0．34，增加了4．7倍；随着废水中初始黄连素浓度的升高，废水COD降解率逐渐降低。O3氧化法是一种有效的黄连素制药废水预处理技术，可以大大提高废水的可生化性。     

铁炭内电解—厌氧—好氧工艺处理阿维菌素废水的试验研究

血清瓶毒性试验表明，AVM对厌氧消化产生强烈的抑制作用，AVM废水经铁炭内电解参处理后，COD和AVM的去除率分别达到19．5％和68．5％，可大大降低废水的毒性，预处理出水再经UASB＋生物接触氧化反应器进一步处理，当生化系统进水COD为6000－6500mg/L时，出水COD为250－280mg/L，总COD去除率达到95．6％，出水达到生物制药行业排放标准。     

二氧化氯催化氧化处理难降解废水技术的研究

研究了二氧化氯化学氧化体系和二氧化氯催化氧化体系。实验结果表明：单用二氧化氯化学氧化处理COD为3500mg／L的酸性大红染料配制废水时，最佳反应pH值为6—8，氧化剂经济用量为1000mgClO2／L废水，反应时间为60min，COD去除率可达50％左右，氧化指数(COD削减量：ClO2投加量)=2．3。当二氧化氯与自制催化剂所组成的催化氧化体系用于对酸性大红染料配制废水的处理时，最佳反应pH值为2左右，氧化剂经济用量为800mgClO2／L废水，反应时间为45—60min，COD去除率可达80％以上，氧化指数=3．5，去除每kg COD氧化剂费用为3．7元人民币，并且废水的可生化性有很大的提高，效果明显优于二氧化氯化学氧化。经济技术评估表明，二氧化氯催化氧化法是一种新型高效的处理难降解废水的技术，有着广阔的应用前景。     

臭氧氧化6-APA制药厂生化处理出水的特性及动力学

通过现场实验研究了6-APA制药厂生化处理出水的臭氧氧化特性及其动力学规律。结果表明，当臭氧浓度为27．5mg／L，气水接触时间为80min时，COD、UV254、NH3-N和色度的去除率分别可达72．95％、73．28％、72％和96．25％，达到《发酵类制药废水工业水污染物排放标准》（GB21903—2008）排放控制要求。拟合结果表明，在0～10、10～30和30～90min时段内，臭氧氧化过程遵循拟一级反应，但反应速率逐渐降低。当气水接触时间为30min时，废水可生化性可由0．1提高至0．35，采用臭氧／生物处理的联合工艺也有望使出水达到相同的排放控制要求。     

垃圾填埋场渗滤液物化深度处理研究

通过Fenton法和结合聚合硫酸铁的混凝作用，实现垃圾渗滤液氧化塘出水COD的深度处理；并利用水泥水化产物的凝胶物质，强化COD去除率。30％H2O2投加量为0．75mL／L、七水硫酸亚铁投加量为1．5g／L、n（H2O2）：n（Fe^2＋）=1．2：1（摩尔比）时，Fenton法对渗滤液COD的去除率可达52％；水灰比为2：1、搅拌24h的水泥水化物将Fenton法的出水pH值从4调至10，该工艺流程总的COD去除率为73．6％，较普通的Ca（OH）2调节法提高9．3％，出水COD可以从进水的1200mg／L降至315mg／L。     

混凝吸附及化学氧化深度处理焦化废水

以蒙脱石、凹凸棒石、次氯酸钙和PAC、PAM为基本材料，对焦化废水二级生化出水进行深度处理。实验结果表明：蒙脱石与凹凸棒石以4：1的比例配合使用，可明显提高焦化废水中COD和色度去除率；采用次氯酸钙作为氧化剂，可进一步提高焦化废水的脱色率和COD去除率，处理间差异达到极显著和显著水平；去除COD的最优实验条件为：粘土矿物（蒙脱石：和凹凸棒石=4：1）添加量4．0g／L、氧化剂（次氯酸钙）添加量1．0g／L、絮凝剂（聚合氯化铝：聚丙烯酰胺=15／1）添加量0．15g／L，处理后色度去除率达到97．0％，COD去除率达到69．1％；脱色的最优实验条件为：粘土矿物添加量4．0g／L、氧化剂添加量1．0g／L、絮凝剂添加量0．2g／L，处理后色度去除率达到98．5％，COD去除率达到66．4％。     

Fenton-接触氧化联合工艺处理铁合金镀件电镀前处理废水

电镀前处理废水中含有大量难降解有机物,成分复杂,用传统生化法难以处理达标。本实验采用Fenton氧化技术对前处理废水进行预处理,再用生物接触氧化技术后续降解COD,使出水中COD达到《电镀污染物排放标准》(GB21900-2008)表3的水质要求。实验采用实际电镀生产废水,COD=300 mg/L,通过芬顿-生物接触氧化因素实验,优化工艺参数,去除率可达到83%以上,COD降到50 mg/L以下.最佳芬顿反应参数为:pH=3.0,COD/H2O2=1.5,Fe2+/H2O2=2,反应时间t=10 min;生物接触氧化法最佳水力停留时间为7 h,进水pH在6~8之间。     

Evaluation of trichloroethene recovery processes in heterogeneous aquifer cells flushed with biodegradable surfactants

The ability of two biodegradable surfactants, polyoxyethylene (20) sorbitan monooleate (Tween 80) and sodium dihexyl sulfosuccinate (Aerosol MA), to recover a representative dense non-aqueous-phase liquid (DNAPL), trichloroethene (TCE), from heterogeneous porous media was evaluated through a combination of batch and aquifer cell experiments. An aqueous solution containing 3.3% Aerosol MA, 8% 2-propanol and 6 g/l CaCl(2) yielded a weight solubilization ratio (WSR) of 1.21 g TCE/g surfactant, with a corresponding liquid-liquid interfacial tension (IFT) of 0.19 dyn/cm. Flushing of aquifer cells containing a TCE-DNAPL source zone with approximately two pore volumes of the AMA formulation resulted in substantial (>30%) mobilization of TCE-DNAPL. However, a TCE mass recovery of 81% was achieved when the aqueous-phase flow rate was sufficient to displace the mobile TCE-DNAPL toward the effluent well. Aqueous solutions of Tween 80 exhibited a greater capacity to solubilize TCE (WSR=1.74 g TCE/g surfactant) and exerted markedly less reduction in IFT (10.4 dyn/cm). These data contradict an accepted empirical correlation used to estimate IFT values from solubilization capacity, and indicate a unique capacity of T80 to form concentrated TCE emulsions. Flushing of aquifer cells with less than 2.5 pore volumes of a 4% T80 solution achieved TCE mass recoveries ranging from 66 to 85%, with only slight TCE-DNAPL mobilization (<5%) occurring when the total trapping number exceeded 2 x 10(-5). These findings demonstrate the ability of Tween 80 and Aerosol MA solutions to efficiently recover TCE from a heterogeneous DNAPL source zone, and the utility of the total trapping number as a design parameter for a priori prediction of DNAPL mobilization and bank angle formation when flushing with low-IFT solutions. Given their potential to stimulate microbial reductive dechlorination at low concentrations, these surfactants are well-suited for remedial action plans that couple aggressive mass removal followed by enhanced bioremediation to treat chlorinated solvent source zones.     

The variation of street air levels of PAH and other mutagenic PAC in relation to regulations of traffic emissions and the impact of atmospheric processes

The occurrence of particle associated PAH and other mutagenic PAC was determined in 1996 in the street air of Copenhagen. In addition, particle extracts were tested for mutagenicity. The measurements were compared with previous measurements in 1992/1993. The levels had decreased in this period. The decrease was caused by an implementation of light diesel fuels for buses and the exchange of older petrol-driven passenger cars with catalystequipped new ones. About 65% of the reduction was caused by the application of the light diesel fuels. Under special conditions, chemical processes in the atmosphere produced many more mutagens than the direct emissions. The concentrations of S-PAC and N-PAC were 10 times lower than those of PAH, while the levels of oxy-PAH were in the same order of magnitude as those of PAH. Benzanthrone, an oxy-PAH, is proposed to be formed in the atmosphere in addition to direct emissions. Benzo(a)pyrene, often applied as an air quality criteria indicator, was photochemically degraded in the atmosphere. A strong increase in the mutagenic activities was observed to coincide with a depletion of benzo(a)pyrene.     

Chloroaromatic pollutants in mussels incubated in two finnish watercourses polluted by industry

Concentrations of different chlorinated compounds were measured in mussels incubated in two polluted watercourses, a river (the River Kymijoki) and a lake (Lake Vanaja) for four weeks in summer 1995. The sum concentrations of polychlorinated phenols (PCP) and biphenyls (PCB) were both about 1 μg/g lipid weight (lw) in Lake Vanaja mussels, while in the River Kymijoki mussels PCPs were non-detectable and PCBs were measured 120 ng/g lIw. The concentrations of toxic polychlorinated dibenzo-p-dioxin (PCDD) and dibenzofuran (PCDF) congeners ranged between <17 and 370 pg/g Iw in Lake Vanaja mussels and between <38 and 11,000 pg/g lw in the River Kymijoki mussels. Polychlorinated diphenyl ethers (PCDE) were detected in the mussels incubated in the River Kymijoki (0.4–1.1 ng/g Iw), but not in those incubated in Lake Vanaja. Polychlorinated phenoxyanisoles (PCPA) were measured 33 ng/g lw and polychlorinated phenoxyphenols (PCPP) 300 ng/g lw in the mussels incubated in the River Kymijoki. PCPAs were also detected in reference samples, which were sediment and pike from the River Kymijoki and Baltic salmon, seal and white-tailed sea eagle.     

Teratological effects of pesticides in vertebrates: a review

Abstract

In the last decades, the use and misuse of pesticides in the agriculture have increased, having a severe impact on ecosystems and their fauna. Although the various effects of pesticides on biodiversity have been already documented in several studies, to our knowledge no consistent overview of the impact of pesticides in vertebrates, both terrestrial and aquatic, is available. In this review, we try to present a concise compilation of the teratogenic effects of pesticides on the different classes of vertebrates – mammals, birds, reptiles, amphibians and fish.     

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.     

Book review

The Pesticide Manual ‐ A World Compendium, 8th Edition, C.R. Worthing, Editor and S.B. Walker, Assistant Editor, British Crop Protection Council, BCPC Publications Sales, Bear Farm, Binfield, Bracknell, Berkshire RG12 5QE, England. 1987, 1100 pp., UK £50; Overseas £56. ISBN 0–948404–01–9.     

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.     

Knowledge transfer initiative between molecular biologists and environmental researchers and regulators

A Natural Environment Research Council (NERC) funded Knowledge Transfer (KT) workshop was held in the United Kingdom (UK) to identify the needs and opportunities in the application of molecular biology and ‘omics’ techniques to environmental monitoring and risk assessment. Attendees highlighted a lack of effective communication between end-users and researchers as well as difficulties with data interpretation as reasons behind the slow uptake of molecular biology and omics techniques. A number of promising areas in which new techniques could be implemented at a practical level in the very near future were identified, thereby raising the profile of these recent technologies and providing vital proof of concept work. Molecular taxonomy, bacterial source tracking and pre-screening of chemicals for potential toxicities were all viewed as areas in which omics and molecular techniques could have immediate value, with the aim of reducing cost, increasing efficiency and providing more comprehensive data of improved quality.     

The chemical stability of formulations of some hydrolyzable insecticides in aqueous mixtures with hydrolysis catalysts

Abstract

The active ingredients in commercial formulations of malathion, oxamyl, carbaryl, diazinon, and chlorpyrifos diluted to “spray tank”; concentrations with buffered distilled or natural water of pH 4–9 were stable for at least 24 hr. Formulations of trichlorfon were not stable at pH 7 or above but disappearance rates were slower than for the pure chemical in homogeneous solution. Cupric ion was observed to be an effective catalyst for the hydrolysis of a variety of pure organophosphorus insecticides but did not catalyze hydrolysis of the active ingredients of the formulations examined. Increasing the dilution of the formulation increased the susceptibility of malathion, oxamyl, and carbaryl to hydrolysis.     

Organochlorine compounds in a three-step terrestrial food chain

The concentrations of 15 organochlorine chemicals (PCBs and pesticides) were studied in a Central European oak wood food chain system: Great tit (Parus major), caterpillars (Tortrix viridana, Operophtera brumata, Erannis defoliaria), and oak-leaves (Quercus robur). Juvenile tits receive organochlorines from the mother via egg transfer and, eventually to a greater extent, from the caterpillar food source during nestling period. The concentrations of PCB 153 (2,2′,4,4′,5,5′-hexachlorobiphenyl, the most abundant in this study) was found in leaf material at ca. 1 ng/g, in caterpillars 10 ng/g, and in bird eggs 170 ng/g on an average and on a dry mass basis.