PCR技术在水生毒理学研究中的应用

介绍了聚合酶链式反应(PCR)技术的基本原理,并在此基础上综述了PCR技术在水生毒理学研究中的应用及国内外最新研究进展,其中涉及的模式生物包括原生动物、浮游植物、浮游动物和鱼类等。PCR技术不仅为污染物对水生生物的毒性检测带来了便利,还有助于从分子水平上阐述污染物的毒性作用机制。最后指出了目前PCR技术应用的局限性及未来的发展前景。     

水质生物毒性在线监测技术研究进展

从生物分子、细胞、个体、种群和群落水平，系统介绍了国内外研发的水质毒性在线监测技术，归纳分析了各种技术的特点及应用，并提出了其发展前景与趋势。     

长江流域全氟化合物污染态势与生态效应

简述了PFASs在长江流域上、中、下游水环境中的空间分布格局和时间变化趋势，探讨了其生物蓄积效应、淡水生物毒性效应和生态风险评价。指出，PFASs广泛赋存于长江流域从上游至下游的干流和支流及湖泊之中，其平均值低于我国其他主要流域；PFOA在长江流域内环境浓度最高，而PFOS在近10年环境管控措施下浓度降至极低，PFBS、PFBA和PFHxA等短链物质正作为替代物使用，可能在未来出现升高趋势。长江流域内水生动物（包括食用鱼类）能够从环境中富集PFASs并通过食物链传输，在其血液、肌肉和内脏中蓄积。虽然目前长江流域生态风险评价表明PFASs总体上风险为低级，但局部高浓度地区仍可能对敏感生物造成基因表达受损等毒性效应。     

城市区域大气颗粒物的健康效应研究

从大气颗粒物的来源和转化、人体损伤及毒理学角度3个方面探讨了其对人体健康效应的影响。结果表明,次微米和纳米粒径级别的大气颗粒物及其化学组成能在最大程度上损伤人体机能。粒径不一的颗粒物有不同的沉积机制、沉积部位和沉积量,化学价态是重金属离子毒性大小的首要因子。从次微米级水平来研究颗粒物的毒性,才能为制定更为有效的大气颗粒物污染防治措施以及在研究大气颗粒物对人体损伤机理方面提供相应的科学依据。     

环境中合成麝香污染现状研究

合成麝香广泛分布于环境中,难降解,易生物富集,对水生生物和人体均呈现一定的生物毒性.综述了合成麝香在环境中的污染现状和分布特点,以及在水生生物和人体中的生物富集作用,并对合成麝香污染研究进行了展望.     

环境中合成麝香污染物的研究进展

介绍了合成麝香的分类与生物毒性,综述了环境中合成麝香的分离富集技术及定性与定量分析方法.指出合成麝香化合物具有较强的生物富集能力和一定的毒副作用,我国应对环境中合成麝香的污染状况开展监测和风险评价.     

对苯二酚对海洋底栖双壳类毛蚶和紫贻贝毒性效应研究

通过对中国近岸常见底栖双壳类毛蚶（Scapharca subcrenata）、紫贻贝（Mytilus edulis）急性和慢性毒性试验，运用Log-logistic模型及Weibull毒性效应阈值模型计算对苯二酚对2种受试生物的半致死效应浓度（LC₅₀）、非检测效应浓度（NDEC)及无观测效应浓度（NOEC）；分析慢性毒性试验对受试生物体质量、体长及消化腺超氧化物歧化酶（SOD）活性的影响。结果显示，对苯二酚对毛蚶、紫贻贝的LC₅₀分别为34.10和66.50 mg/L，NDEC分别为0.36和0.50 mg/L，NOEC分别为0.40和0.60 mg/L。慢性试验周期内受试生物体质量、体长的组内与组间差异不显著（P>0.1）；SOD酶活性仅在个别时间段对照组和处理组间存在显著差异（P<0.05）。     

工业废水毒性评估方法与应用研究进展

针对中国缺乏规范的工业废水毒性评估体系的现状，系统归纳了国外在毒性检测、毒性评价标准与方法方面的成功经验。在明确了工业废水急性毒性检测的重要性基础上，重点分析了美国全废水毒性测试法（WET）及其在工业废水评价中的应用；并结合对毒性评价标准的阐述，系统总结了发展较成熟的毒性鉴别评价法（TIE）和效应导向分析法（EDA）的流程与应用实例，以期为中国工业废水毒性检测评估和监管提供参考。     

土壤环境中锑的生物毒性评价方法比较

锑的生物毒性测试可以间接反映锑及其化合物对生物与生态系统的影响。在简要介绍锑在土壤环境中赋存特征的基础上,综述了不同类型生物对土壤及其浸提液中锑的毒性响应,比较了不同的生物毒性测试方法在土壤环境中锑污染识别的可行性及适应性,并提出了考虑土壤性质及老化时间对锑生物毒性评价的影响,以及使用不同营养等级指示生物(微生物、动物和植物)评价等建议。     

微塑料及卤代有机污染物在洞庭湖的赋存研究进展

洞庭湖是中国第二大淡水湖,其生态价值十分重要。目前洞庭湖新污染物相关研究比较缺乏,也没有系统的综述进行归纳总结。微塑料和卤代有机污染物是近年来备受关注的新污染物,搜集历年研究成果,对这2类污染物在洞庭湖的污染水平、分布方式、污染来源进行归纳总结：洞庭湖微塑料污染水平在世界范围内处于中等,其主要来源包括上游输入、居民日常生活、农业生产及工业生产,湖泊各区域微塑料污染水平差异明显。卤代有机污染物在洞庭湖的浓度呈现随时间推移而降低的趋势,目前整体生态风险较低,但生物累积效应仍然值得警惕。在未来研究中应当关注河流与湖泊之间的相互影响,探究微塑料和卤代有机污染物对洞庭湖区生物造成的生物毒性,建立科学完善的监测方法并结合湖区具体情况对污染防治措施及污染物处理技术开展研究。     

Enantioselective aquatic toxicity of current chiral pesticides

Chiral pesticides are ubiquitous in the aquatic environment, and their enantioselectivities in aquatic toxicity are known to be complicated. The difference in enantioselective effects between enantiomers may sometimes differ by approximately 100-fold or more, which makes it important to incorporate enantioselective effects into the risk assessment of chiral pesticides. In this paper, we reviewed relevant work on the aquatic toxicity of chiral pesticides with an emphasis on the enantioselective aquatic toxicity under both chronic and acute exposure conditions. We provided a personal account of the importance of studies on molecular mechanisms of developmental toxicity and specific endpoints such as vitellogenin, yolk sac edema and pericardial edema in future research. Given the widespread use of chiral pesticides, we suggest that a more comprehensive understanding of the significance of enantioselective aquatic toxicity will be very helpful in improving risk assessment and regulation of chiral pesticides.     

Toxicity of propargylic alcohols on green alga--Pseudokirchneriella subcapitata

The present study evaluates the toxicity of 34 propargylic alcohols, including primary, primary homo-, secondary, and tertiary alcohols, based on their effects on phytoplankton. A closed-system algal toxicity test was applied because the closed-system technique presents more realistic concentration-response relationships for the above compounds than the conventional batch tests. The green alga, Pseudokirchneriella subcapitata, was the test organism and final yield and growth rate were chosen as the test endpoints. Among all the propargylic alcohols tested, 1-pentyn-3-ol is the most toxic compound with its EC50 equal to 0.50 mg L(-1), which can be classified as a "R50" compound (very toxic to aquatic organisms, EC50/LC50 < 1 mg L(-1)), following the current practice for classification of chemicals in the European Union (EU). There are several other compounds including 2-decyn-1-ol, 3-decyn-1-ol, 1-hexyn-3-ol, 3-butyn-2-ol, and 3-hexyne-2,5-diol, which deserve more attention for their possible adverse impact on the aquatic environment, because these alcohols can be classified as "R51" compounds (toxic to aquatic organisms, EC50/LC50 between 1 and 10 mg L(-1)). Compared to the base-line toxicity relationship (narcosis QSAR) derived previously, tertiary propargylic alcohols can be identified as nonpolar narcotic chemicals, while secondary alcohols and primary alcohols with low molecular weight generally exhibit obvious excess toxicity in relation to the base-line toxicity. Finally, quantitative structure-activity relationships were established for deriving a preliminary estimation of the toxicity of other propargylic alcohols.     

Toxicity assessment of individual ingredients of synthetic-based drilling muds (SBMs)

Synthetic-based drilling muds (SBMs) offer excellent technical characteristics while providing improved environmental performance over other drilling muds. The low acute toxicity and high biodegradability of SBMs suggest their discharge at sea would cause minimal impacts on marine ecosystems, however, chronic toxicity testing has demonstrated adverse effects of SBMs on fish health. Sparse environmental monitoring data indicate effects of SBMs on bottom invertebrates. However, no environmental toxicity assessment has been performed on fish attracted to the cutting piles. SBM formulations are mostly composed of synthetic base oils, weighting agents, and drilling additives such as emulsifiers, fluid loss agents, wetting agents, and brine. The present study aimed to evaluate the impact of exposure to individual ingredients of SBMs on fish health. To do so, a suite of biomarkers [ethoxyresorufin-O-deethylase (EROD) activity, biliary metabolites, sorbitol dehydrogenase (SDH) activity, DNA damage, and heat shock protein] have been measured in pink snapper (Pagrus auratus) exposed for 21 days to individual ingredients of SBMs. The primary emulsifier (Emul S50) followed by the fluid loss agent (LSL 50) caused the strongest biochemical responses in fish. The synthetic base oil (Rheosyn) caused the least response in juvenile fish. The results suggest that the impact of Syndrill 80:20 on fish health might be reduced by replacement of the primary emulsifier Emul S50 with an alternative ingredient of less toxicity to aquatic biota. The research provides a basis for improving the environmental performance of SBMs by reducing the environmental risk of their discharge and providing environmental managers with information regarding the potential toxicity of individual ingredients.     

Synergistic effects of metal nanoparticles and a phenolic uncoupler using microdroplet-based two-dimensional approach

A droplet-based microfluidic technique for testing multiple reagent concentrations is presented. We used this experimental approach to study combined effects of gold (AuNP) and silver nanoparticles (AgNP) with the phenolic uncoupler 2,4-dinitrophenol (DNP) with respect to the growth of Escherichia coli. In order to evaluate the toxicity of binary mixtures, we first encapsulated the E. coli cells and particle mixtures inside the microdroplets using PEEK (polyetherketone) modules. Two-dimensional concentration spaces with about 500 well separated droplets were addressed. We subsequently analyzed the cell growth, the viability and the autofluorescence intensity (metabolic activity) of the bacteria with a micro-flow-through fluorometer and photometer. Dose-dependent synergistic effects were found for the binary mixture of AgNPs and DNP, which indicated a stronger interaction in the mixture than it was expected from effect summation. For the binary mixture of DNP and AuNPs in non-toxic concentrations, we found only weak synergistic effects at low DNP concentrations. Furthermore, the non-toxic tested AuNPs causes effect summation in the binary mixture with the phenolic uncoupler. In general, we demonstrated the efficiency of a droplet-based microfluidic system for fast high-throughput screenings of binary and multiple mixtures. This work also confirmed the relevance of highly resolved droplet-based assays for the miniaturization of ecotoxicological aquatic test systems.     

城市黑臭河道治理前后沉积物对大型溞的毒性变化监测与评价

以常州市典型城市黑臭水体神童滨为对象,利用大型溞-固定沉积物毒性实验,成功地对治理前、后污染河流沉积物毒性变化进行监测,获得较浸出液毒性实验更灵敏的结果。结果表明,治理前污染河流4个采样点沉积物的毒性均为中毒级,治理后,3个采样点的毒性下降到微毒级,1个点位毒性为无毒级。根据河道整治前、后的沉积物对水生生物的综合毒性变化,评价河道治理前的危害程度和治理后的生态安全性,为采取合理的整治方法以达到可持续治理效果提供科学依据。     

Indicators of ecosystem health at the species level and the example of selenium effects on fish

Chemical monitoring of aquatic ecosystems describes the chemical exposures of aquatic biota and measures the success of pollution control. However, meeting water quality criteria cannot assure that aquatic biota are protected from the effects of unexpected chemicals, mixtures and interactions between toxicity and environmental stressors.Biological monitoring is an obvious solution since aquatic biota integrate spatial and temporal variations in exposure to many simultaneous stressors. Top predators, typical of specific ecosystems (e.g. lake trout in cold water oligotrophic lakes) indicate whether environmental criteria have been met. The presence of naturally reproducing, self-sustaining and productive stocks of edible fish demonstrates a high quality environment. If these conditions are not met, there is a clear sign of environmental degradation. Specific changes in population structure and performance may also diagnose which life stage is affected and the nature of the stressor.Unfortunately, environmental managers cannot rely solely on populations, communities or ecosystems to indicate chmical effects. The lag between identifying a problem and finding a cause may destroy the resource that we wish to protect, particularly where chemicals are persistent.A solution to this dilemma is the measurement of primary or secondary responses of individual organisms to chemical exposure. Since toxicity at any level of organization must start with a reaction between a chemical and a biological substrate, these responses are the most sensitive and earliest sign of chemical exposure and effect.Application of this idea requires research on molecular mechanisms of chemical toxicity in aquatic biota and adaptation of existing mammalian diagnostic tools. Since relevance of biochemical responses to populations and ecosystems is not obvious, there is a need to study the links between chemical exposure and responses of individuals, populations and ecosystems.The recognition of chemical problems and cause-effect relationships requires the integration of chemical and biological monitoring, using the principles of epidemiology to test the strength of relationships and to identify specific research needs. The contamination of a reservoir with selenium and impacts on fish populations provide an excellent example of this approach.     

大型蚤在线生物监测系统研究

近年来,世界范围内突发性废水泄漏事件频发,在引起人们对水质问题恐慌的同时,也促进了饮用水在线监测与早期污染预警系统的发展。生物监测可以对污染环境下多污染物的联合毒性进行有效评估,具有传统化学监测所不具备的优点,已成为判定水质是否对水生生物存在影响、是否符合人类安全饮用的有效依据和手段。介绍了大型蚤在线生物监测系统的多通道流通生物测试室和生物传感器系统,并对世界范围内的研究与应用情况做了研究综述。目前,采用大型蚤作为指示生物的在线监测系统已在饮用水水质监测方面成功实现,但其在工业废水接管过程中毒性评估和早期预警的研究和应用上尚有不足,有待更加深入地探讨与研究。     

Comparative toxicity of nano-ZnO and bulk ZnO suspensions to zebrafish and the effects of sedimentation, ˙OH production and particle dissolution in distilled water

With the common application of nanoscale zinc oxide (nZnO) and significant potential for its release directly into aquatic environments, it is urgent to carry out research on ecotoxicological impact of nZnO. The characterization of nZnO, the amount of ˙OH in suspensions in the presence of light and the acute toxicity of nZnO and its bulk counterpart suspensions, as well as the acute toxicity of Zn(2+) solution to zebrafish (Danio rerio) at 96 h were studied. It was found that nZnO aggregated into irregular shapes in suspensions, and showed a relationship between its size distribution and concentration. In the presence of light, nZnO suspensions could generate ˙OH, the concentration of which increased with time. Although it was generally thought that ˙OH played a role in the biotoxicity to zebrafish, similar toxicity was observed for the nZnO and bulk ZnO suspensions (96 h LC(50) 3.969 mg L(-1), 2.525 mg L(-1), respectively). Furthermore, the sedimentation of nZnO and bulk ZnO in suspensions, and the accumulation of Zn in zebrafish were studied. The results showed that dissolved Zn(2+), from nZnO and bulk ZnO in suspensions, were toxic to zebrafish, while the aggregation and sedimentation of nZnO suspensions reduced the toxicity of nZnO. However, Zn(2+) may not be the main source of acute toxicity of nZnO and bulk ZnO to zebrafish. The experimental results highlight the importance of a systematic assessment of toxicity mechanisms of metal oxide nanoparticles (NPs) to determine definitively whether their toxicity is caused by nano-effects.     

Assessing the impact of chloroacetanilide herbicides and their metabolites on periphyton in the Leyre River (SW France) via short term growth inhibition tests on autochthonous diatoms

The Leyre River is the main tributary to the Bassin d'Arcachon lagoon. Herbicides belonging to the chloroacetanilide class have been found in the river (S-metolachlor and acetochlor) as well as some of their metabolites at higher concentrations. As the environmental toxicity of these molecules is not well known, ecotoxicological tests have been carried out on river periphyton at different levels of biological diversity: from the clone of one diatom species (Nitzschia nana) to the population of the same species (several clones) up to the multi-specific species community dominated by diatoms. Moreover, tests were performed on diatoms coming from an unpolluted upstream site and from a contaminated downstream site, in order to investigate possible tolerance acquisition to pollutants. The method consisted in measuring diatom growth inhibition at different doses of each substance from the increase of chlorophyll-a concentration after 4 days. It resulted that acetochlor was clearly more toxic than S-metolachlor at all levels of biological diversity. EC(50) values estimated from the tests suggest no effect of contaminants on diatom growth or biomass in the river. The toxicity of the metabolites appeared very low compared to that of their parent compounds. No difference in tolerance to the herbicides was demonstrated between summer diatom communities from the two sites in spite of different specific compositions. However, concerning the populations of N. nana isolated in winter following the highest herbicide concentrations in the river (about 0.5 μg L(-1)), the downstream population showed a higher tolerance to acetochlor but there was no co-tolerance to S-metolachlor. Thus, it appeared that acetochlor represents the highest toxic pressure on periphyton among the other contaminants in the Leyre River.