污染土壤修复效果评定方法的研究

在实施污染土壤修复的环境工程后,需要通过灵敏和有效的评定方法对污染土壤修复的效果进行评定.然而,单纯依靠化学方法进行污染土壤修复效果的评定,不能揭示土壤的整体质量特征,因此需要生态毒理方法作为相互补充的手段.本文概述了植物毒性评定法、陆生无脊椎动物评定法和土壤微生物评定法及其在污染土壤修复效果评定中的应用,并对污染土壤修复效果评定方法的发展前景进行展望.     

Ecotoxicological effects of mixed pollutants resulted from e-wastes recycling and bioaccumulation of polybrominated diphenyl ethers in Chinese loach (Misgurnus anguillicaudatus)

To understand potential ecotoxicological effects of electrical and electronic equipment waste (e-waste) recycling and polybrominated diphenyl ethers (PBDEs) bioaccumulation in loaches, a semi-field experiment using Chinese loach (Misgurnus anguillicaudatus) as experimental fish was performed. Larval loaches were kept into net-cage for three months in an e-wastes recycling site and a reference site in Southeastern China. There was significant difference of the survival rate between the loaches from the e-wastes recycling site (27%, 19/70) and from reference site (70%, 49/70). Histopathological responses were also found in all the livers examined in loaches from the e-wastes recycling site. These results showed that mixed pollutants resulted from e-wastes recycling led to ecotoxicological effects on loaches. The bioaccumulation of polybrominated diphenyl ethers (PBDEs), the main pollutants in e-waste, in loaches was also studied in this e-wastes recycling site, the mean concentrations of total PBDEs in sediment was 6726.17 ng/g wet weight and in water samples was 4.08 ng/L (dissolved phase). BDE209 was the dominant congener in sediment and with relatively high concentration in water. Relatively low concentration of BDE209 (less than 0.01% of total PBDEs) and high concentration of BDE47 (up to 39.34% of total PBDEs) were detected in loaches.     

土壤四环素污染对小白菜幼苗生长发育的生态毒性

采用土培盆栽试验模拟研究了土壤四环素污染对小白菜幼苗生长发育的生态毒性.结果表明,1～100 mg/kg四环素暴露促进了小白菜的茎伸长,但抑制了小白菜的根伸长和鲜重.100 mg/kg四环素处理28 d后,小白菜根长抑制率达到36.0%,鲜重抑制率达到34.6%.随着四环素暴露时间的延长,100 mg/kg四环素处理的...     

磺胺甲恶唑对小麦叶片蛋白和叶绿素含量及SOD酶活性的影响

为了探明磺胺甲恶唑(sulfamethoxazole,SMZ)的生态毒理效应,通过实验室人工控制毒理实验,研究了低浓度SMZ暴露对小麦体内超氧化物歧化酶(SOD)活性、叶绿素(CHL)和蛋白质(SP)含量的影响.结果显示:染毒7d后,各浓度组小麦叶片的SOD活性均被显著诱导(P＜0.0l),并且染毒浓度的升高增强了SOD的活性,表明SMZ暴露胁迫下,小麦可启动自身的保护机制以最大限度地减少自由基损伤.而小麦叶片的CHL含量,随着SMZ染毒浓度的增加而逐渐降低.并且当SMZ暴露浓度较高时,小麦叶片的CHL含量被显著抑制(P＜0.05)).当SMZ染毒浓度为0.05～ 0.50 mg· L-1时,SP的含量被显著诱导(P＜ 0.01));1.00 mg·L-1SMZ对SP的含量产生显著(P＜0.01)抑制,这说明SMZ染毒剂量将对蛋白质的合成产生严重影响.综上,SOD的活性变化可反映出SMZ暴露对小麦的污染效应及其生态毒性作用,但将其作为评估SMZ污染暴露的生物标志物有待于进一步深入研究.     

环境基准研究与环境标准制定进展及展望

环境基准是一个非常棘手且具有挑战性的科学难题,环境标准制定与修订是一项长期的、艰巨的任务。根据国际上该方向近年来的发展,对环境基准和环境标准的概念与内涵进行了论述,对过去的认识进行了纠正,指出:环境基准不等于环境质量基准,环境基准应该包括环境质量基准和污染环境修复基准2个方面;相应地,环境标准则应包括环境质量标准和污染环境修复标准2个部分。在此基础上,概述了国际和国内有关环境质量基准研究方面取得的显著成绩,列举了法国(作为西欧的代表)、加拿大(作为美洲的代表)和意大利(作为中欧的代表)在环境质量标准制定过程中的先进做法,介绍了美国、英国和俄罗斯等国家在污染环境修复基准研究与污染环境修复标准制定等方面的进展。最后,对我国今后环境基准的研究进行了展望。     

环境中两种沐浴露污染对大型蚤的生态毒性效应

选用2种在市场上畅销的护肤品(六神沐浴露和玉兰油沐浴露),采用大型蚤(daphnia magna straus)的急性毒性标准测定方法,初步研究和评价了2种沐浴露对水环境污染的生态毒性.结果表明,六神沐浴露24h的LC50和EC50值分别为96.76和81.72 mg·L-1,48 h的LC50和EC50值分别为78.42和72.93 mg·L-1;玉兰油沐浴露24h的LC50和EC50值分别为91.13和84.95 mg·L-1,48h的LC50和EC50值分别为80.11和78.51 mg·L-1.2种沐浴露对大型蚤的致死和抑制效应与其浓度呈明显正相关关系,且毒性效应随作用时间的延长而增强.     

Concentrations and distributions of 18 organochlorine pesticides listed in the Stockholm Convention in surface sediments from the Liaohe River basin,China

Organochlorine pesticides (OCPs) were analyzed in 26 surface sediment samples from the Liaohe River basin, and the distributions of and potential environmental risks posed by OCPs in the basin were evaluated. Eighteen OCPs listed in the Stockholm Convention were determined using isotope-dilution gas chromatography–high resolution mass spectrometry. This is the first study of hexachlorobenzene (HCB) in the Liaohe River basin sediments. The total OCP concentrations were 0.39–68.06 ng g^?1 dry weight. The total α-, β-, γ-, and δ-hexachlorocyclohexane (HCH), the total dichlorodiphenyltrichloroethane (DDT – p,p′-dichlorodiphenyldichloroethane (DDD), p,p′-dichlorodiphenyldichloroethylene (DDE), o,p^'-DDT, and p,p′-DDT), and the HCB concentrations in the sediment samples were 0.1–28.48 ng g^?1 (mean 4.01 ng g^?1), 0.08–6.52 ng g^?1 (mean 3.07 ng g^?1), and 0.18–24.8 ng g^?1 (mean 4.38 ng g^?1), respectively. The HCB concentrations were higher than the concentrations of the other OCPs, and the HCHs and HCB together were the dominant OCPs. β-HCH was the most abundant HCH isomer. The concentrations of DDTs and other OCPs were relatively low, and the (DDE+DDD)/DDT ratios (>0.5) and DDD/DDE ratios (<1) indicated that no recent DDT inputs had occurred in the Liaohe River system. The main sources of HCHs were probably the historical production and agricultural use of HCH in the study area. The DDT and HCH concentrations were generally below or similar to the concentrations that have been found in other parts of the world. An ecotoxicological evaluation indicated that HCHs in surface sediments pose slight risks to human and ecological health in the Liaohe River basin.     

平衡分配法在土壤环境质量基准推导中的相关问题研究

为了促进土壤环境质量标准的修订进程,势必要全面系统地开展土壤环境质量基准的研究工作。理论上,水、土之间是一个相互联系、互相依赖和关系密切的系统;同时,水生态毒理及其质量基准研究起步早,研究方法相对成熟。因此,从水质基准来推导土壤环境质量基准具有一定的科学依据与实践意义。本文首先从土-水系统中污染物分布的影响因素及其环境行为两方面简要阐述污染物在土-水系统中的分布规律;然后,扼要介绍了平衡分配(Eq P)理论及其在环境质量基准研究中的应用;之后,从Eq P方法的不确定性、毒理数据选用的争议性、Koc的局限性和分配系数的确定方法选择性等方面,探讨了平衡分配法在土壤环境质量基准研究中应用的瓶颈问题;最后,对此项研究进行了总结与展望。     

Ecotoxicological assessment of di use pollution using biomonitoring tool for sustainable land use in Thailand

As a developing country, Thailand has a significant issue with di use pollution of the soil ecosystem due to an indiscriminate use of agrichemicals and poorly regulated disposal of a wide variety of hazardous wastes. Practical risk assessment tools based on locallyoccurring species are needed to assess the e ects of di use pollutants on the soil ecosystem in Thailand because reliance on soil criteria developed for overseas conditions may provide inadequate protection. Native soil organisms in Thailand may be more or less sensitive to contaminants compared to overseas test species. This article described a biological indicator approach for ecological risk assessment of di use pollution in the soil ecosystem of Thailand from pesticide application with the aim of developing standardized protocols using native species and locally generated data to better evaluate the ecological risks of non-point source soil pollution. It was found that ecotoxicological assessment provided a better understanding of the ecological impacts that di use pollution induced on Thai environmental conditions. Thai soil biota species were more sensitive to soil contaminants than similar species overseas. Soil series also had an influence on the ecotoxicology of contaminants to soil biota. Collembolan, Cyphoderus sp., was demonstrated as a useful alternative test species to Folsomia candida (international test species) for terrestrial ecotoxicological testing of Thai soils. In addition, the soil biota activities such as soil respiration and earthworm avoidance including soil biodiversity and the litter bag decomposition technique are also good tools to assess the e ects of di use pollution by pesticides on the soil ecosystem of Thailand.     

乙草胺对小麦生理机能的影响与生物标记物识别

对乙草胺胁迫下小麦幼苗叶片的超氧化物歧化酶（SOD）、过氧化物酶（POD）活性、可溶性蛋白含量、丙二醛（MDA）以及叶片中叶绿素含量的变化进行了研究.结果表明,乙草胺处理小麦幼苗1 d后,叶片MDA含量显著增加,说明了乙草胺处理诱导有毒活性氧（AOS）生成,但随着处理时间的延长,不同浓度处理与对照的差异逐渐减小.对小麦叶片中POD活性变化的研究表明,在乙草胺胁迫的开始阶段,植物有能力抵抗低浓度乙草胺污染所产生的氧化胁迫,但是,随着暴露时间的延长和污染物浓度的增加,这种抵抗能力将会消失.对小麦SOD活性的研究表明,小麦叶片中POD酶活的上升可能与其它途径而不是SOD诱导产生的H₂O₂有关.小麦叶片中MDA含量和POD活性不能作为土壤乙草胺污染的生物标记物.小麦叶片中SOD酶活性有着作为乙草胺污染土壤生物标记物的潜力,但还需要进一步研究.小麦叶片叶绿素含量和可溶性蛋白含量可以作为乙草胺污染胁迫的生物标记物,并且小麦幼苗叶片可溶性蛋白含量与土壤乙草胺浓度之间具有较好的剂量-效应关系.