树脂吸附-NaClO曝气氧化法处理促进剂M废水的研究

研究了苯胺法生产促进剂M废水的治理，通过采用树脂吸附-NaClO曝气氧化二级处理工艺，分步去除有机污染物和硫化物，废水出水可达到国家一级排放标准。根据实验确定了适宜的工艺参数，氧化阶段的实验结果还证实Na-ClO曝气氧化较NaClO搅拌氧化具有更高的去除效率。     

电催化氧化技术处理煤气化废水

采用电催化氧化技术处理煤气化废水一级生化出水,考察了p H值、槽电压、水力停留时间、曝气量对处理效果的影响,将实验条件优化得到其最佳反应条件为:进水p H值为6.0~6.5,槽电压取值为15 V,水力停留时间为2 h,曝气量为5 m3/(m2·h)。在此最优条件下,煤气化废水一级生化出水的COD去除效率达到80%,色度去除效率达到90%。这表明,电催化氧化技术能够降解废水中的有机组分,还能破坏其内部的发色基团,作为煤气化废水一级生化出水的深度处理方法效果显著,成本低廉,出水能达标排放。     

深井曝气工艺处理高浓度制药废水

本废水治理工程是采用深井曝气法作为第一段、组合填料接触氧化法作为第二段的工艺流程处理高浓度抗生素制药废水。6个月的生产运转情况表明,在深井曝气装置污泥负荷3.84kg COD_(Cr)/kg MLSS·d,接触氧化池容积负荷1.33kg COD_(Cr)/m~3·d的条件下,此工艺流程取得了良好的COD_(Cr)去除效率,废水处理成本为0.35元/kg去除COD_(Cr)。文章还对治理工程的工艺设计作了详细介绍。     

类Fenton氧化—好氧移动床生物膜法处理抗生素发酵废水

采用类Fenton氧化-好氧移动床生物膜(MBBR)法处理难降解抗生素发酵废水,探讨了H2O2和草酸投加量对类Fenton氧化工艺以及HRT和曝气量对好氧MBBR反应器的影响.实验结果表明,当类Fenton氧化工艺的最佳操作参数为反应溶液H2O2和草酸初始质量浓度分别为150、45 mg/L、30 W/154 nm紫外灯照射1 h、pH为3.0,在曝气搅拌条件下,COD平均去除率为80.9%.当类Fenton氧化工艺出水pH在7.0时,废水中的污染物还可以进一步被混凝去除.好氧MBBR反应器的最佳工艺参数为HRT 12 h、曝气量0.10 m3/h以及填料填充比(体积比)30%,最终废水COD平均去除率为99.1%,达到<污水综合排放标准>(GB 8978-1996)三级标准要求.     

pH对微气泡臭氧氧化处理染料废水影响

微气泡技术有助于改善废水臭氧氧化处理效果,p H值是影响微气泡臭氧氧化处理性能的重要因素。考察了不同初始p H值条件下,微气泡臭氧氧化处理酸性大红3R废水性能。结果表明,p H值对微气泡曝气中臭氧分解速率具有显著影响,强酸性和碱性条件下,微气泡曝气中臭氧分解速率均明显高于中性条件。同时,酸性和碱性条件下,微气泡臭氧氧化处理酸性大红3R的脱色速率和TOC去除速率明显高于中性条件。酸性条件下臭氧微气泡氧化能力最强,TOC去除速率约为中性条件的2倍,TOC去除率可达83.1%。酸性、碱性和中性条件下TOC去除量与臭氧消耗量的比值(R)分别为0.0372、0.0298和0.0180 mg/mg。不同初始p H值下微气泡臭氧氧化处理酸性大红3R过程中,臭氧利用率均高于99%。     

微生物制剂与玄武岩纤维联用处理城市废水

为了探索一种新型的去除水体中有机物的工艺,以模拟城市废水为研究对象,研究不同工况条件下,复合微生物制剂、组合双环玄武岩纤维填料以及复合微生物制剂与组合双环玄武岩纤维填料结合对模拟城市废水中COD的去除情况。实验结果表明,复合微生物制剂与组合双环玄武岩纤维填料结合在曝气的情况下对COD的去除能力较高。在复合微生物制剂与组合双环玄武岩纤维填料结合的条件下,对COD浓度为500 mg/L左右的模拟城市废水的去除效率可达 97.22%;影响模拟城市废水中COD去除效果的各因素的主次顺序依次为反应时间>曝气时间>投加量=pH;得出最佳工况参数是:复合微生物制剂的投加量为0.05 g/L,曝气时间为72 h,反应时间为96 h,pH为7。     

曝气＋化学絮凝法预处理环氧丙烷废水

根据环氧丙烷废水的特点，应用电化学法处理具有较高的可行性。运用电化学法处理PO废水前必须进行废水预处理，用以提高电流效率和延长极板寿命。采用曝气和化学絮凝结合的方法去除PO废水中的Ca2＋，同时去除部分COD。对曝气、无机絮凝剂（PACl、PFS）和有机絮凝剂（PAM）对PO废水处理过程中的曝气量、曝气时间、投药量、复配和沉降时间等主要影响因子进行了实验研究，通过比较Ca2＋、COD的去除效果、絮凝剂用量、沉降时间、处理成本等方面，在设定的实验参数下得到最佳预处理方案为：曝气量为2．5L／min，曝气45min，投加Na2CO3粉末24kg／t废水，充分混匀后加入PFS＋PAM复配絮凝剂。本方案具有废水处理效果好（Ca2＋的去除率为77．03％，COD的去除率为37．46％）、投药量少（（100＋7．5）g／t废水）、沉降时间短（5min）、处理成本低（0．675元／t废水）等优点。通过对比经预处理和不经预处理后电化学法对COD去除效果、电流和处理后阴极表面，验证了预处理方案的必要性与可行性。     

微生物制剂与玄武岩纤维联斥处理城市废水

为了探索一种新型的去除水体中有机物的工艺，以模拟城市废水为研究对象，研究不同工况条件下，复合微生物制剂、组合双环玄武岩纤维填料以及复合微生物制剂与组合双环玄武岩纤维填料结合对模拟城市废水中COD的去除情况。实验结果表明，复合微生物制剂与组合双环玄武岩纤维填料结合在曝气的情况下对COD的去除能力较高。在复合微生物制剂与组合双环玄武岩纤维填料结合的条件下，对COD浓度为500mg／L左右的模拟城市废水的去除效率可达97．22％；影响模拟城市废水中COD去除效果的各因素的主次顺序依次为反应时间〉曝气时间〉投加量=pH；得出最佳工况参数是：复合微生物制剂的投加量为0．05g／L，曝气时间为72h，反应时间为96h，pH为7。     

曝气+化学絮凝法预处理环氧丙烷废水简

根据环氧丙烷废水的特点，应用电化学法处理具有较高的可行性。运用电化学法处理PO废水前必须进行废水预处理，用以提高电流效率和延长极板寿命。采用曝气和化学絮凝结合的方法去除PO废水中的Ca²⁺，同时去除部分COD。对曝气、无机絮凝剂（PACl、PFS）和有机絮凝剂（PAM）对PO废水处理过程中的曝气量、曝气时间、投药量、复配和沉降时间等主要影响因子进行了实验研究，通过比较Ca²⁺、COD的去除效果、絮凝剂用量、沉降时间、处理成本等方面，在设定的实验参数下得到最佳预处理方案为：曝气量为2.5 L/min，曝气45 min，投加Na₂CO₃粉末24 kg/t 废水，充分混匀后加入PFS+PAM复配絮凝剂。本方案具有废水处理效果好（Ca²⁺的去除率为77.03%，COD的去除率为37.46%）、投药量少（（100+7.5）g/t废水）、沉降时间短（5 min）、处理成本低（0.675元/t废水）等优点。通过对比经预处理和不经预处理后电化学法对COD去除效果、电流和处理后阴极表面，验证了预处理方案的必要性与可行性。     

铁刨花预曝—沉淀—好氧工艺处理印染废水

涤纶经编织物印染废水处理过程中，在调节池内加入铁刨花并予以曝气，一方面形成原电池反应，使进入生化池内的废水Ｂ／Ｃ比从０．２２提高到０．３５；另一方面在初沉池内可减少混凝剂用量，降低运行成本，使传统的接触氧化演变成生物铁接触氧化法，提高了去除污染物的效率。     

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.     

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 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 hematology of cricket frog (Fejervarya limnocharis)

The effect of malathion [diethyl(dimethoxythiophosphorylthio)succinate] at sublethal concentration (0.006 ppm) on hematological parameters of the cricket frog (Fejervarya limnocharis) was studied for 24 hrs to 240 hrs of exposure and remarkable hematological alterations were observed. The study on hematological parameters revealed a highly significant decrease (P < 0.01) in the total erythrocytes count in malathion-exposed animals from 24 hours to 96 hrs of exposure as compared to control. Significant decreases (P < 0.01) of hemoglobin and packed cell volume were also observed from 48 hrs to 240 hrs. A significant increase (P < 0.01) in leucocytes count was noted throughout the exposure period. Elevated numbers of lymphocytes and eosinophils as found in the present study revealed lymphocytosis as well as eosinophilia, suggesting that this was a result of direct stimulation of the immunological defense due to the presence of a toxic substance or may be associated with tissue damage. The cytomorphological and cytopathological study of erythrocytes and leucocytes in malathion-exposed frogs at 0.006 ppm concentration revealed various cytotoxic effects at different exposure times. It was noted that the size and the shape of the erythrocytes were subjected to variation in different blood disorders.     

Relation between forest vegetation, atmospheric deposition and site conditions at regional and European scales

Several monitoring programs have been set up to assess effects of atmospheric deposition on forest ecosystems. The aim of the present study was to evaluate effects on the understorey vegetation, based on the first round of a regional (the Netherlands) and a European forest monitoring program. A multivariate statistical analysis showed surprisingly similar results for both data sets; the vegetation appeared to be largely determined by the ‘traditional’ factors soil, climate, and tree species, but there was a small but statistically significant effect of atmospheric deposition. The effects of deposition include a slight shift towards nitrophytic species at high N deposition in the European network, and towards acidophytic species at high S-deposition in the Dutch network. The relatively small effect of atmospheric deposition is understandable in view of the very large natural variation in environmental conditions. Time series of both vegetation and environment are needed to assess deposition effects in detail.