基于双目视觉技术的海水生物毒性监测方法研究

针对现有海水生物毒性监测方法单一,不能反映全部毒性污染状况的问题,采用双目立体视觉技术,选择贻贝作为海水生物毒性传感器,利用双摄像机不间断拍摄形成三维动态信息,实时分析贻贝的开合角度及频率,最终实现海水生物毒性监测。实验结果表明,本文提出的监测方法可靠性、灵敏度高,能够为海洋生态环境保护提供技术支撑。

洗护用品中的抗菌成分对水生态环境的危害作用

随着抗菌药物在医疗、工农业和日常生活中的广泛应用,水体抗生素污染已经成为全球公共卫生问题。新型冠状病毒肺炎疫情的暴发促使人们对抗菌卫生用品的使用量进一步增加,大量杀菌剂随生活废水排入水体,导致水环境中各种抗菌物质浓度急剧升高,进一步加重了水体的净化负担。洗护用品中的抗菌成分大多具有广谱杀菌作用,排入水体后势必对水中的常居微生物产生危害,增加水中微生物耐药性,同时也给水生生物带来威胁。本文系统总结了洗护用品中最常添加的酚类、含氯类和季铵盐类等杀菌剂在国内外水环境中的浓度分布和对微生物、水生生物的毒性作用,以期为我国科学倡导及管理洗护用品中抗菌成分的添加和使用提供科学依据。

Investigation into the hemolytic activity of tentacle venom from jellyfish Cyanea nozakii Kishinouye

Cyanea nozakii Kishinouye （C. nozakii）, a giant cnidarian of the class Scyphomedusae, order Semaeostomeae and family Cyaneidae, is widely distributed in the East China Sea, the Yellow Sea and the Bohai Sea, and is abundant from late summer to early autumn. Venom produced by C. nozakii during mass agglomerations can contaminate seawater resulting in death of the halobios and seriously damage commercial fisheries. Swimmers and fishermen commonly suffer painful stings from this j ellyfish, resulting in local edema, tingling, breathing difficulties, depressed blood pressure and even death. Such effects arise from the complex mixture of biologically active molecules that make up jellyfish venom. In the present study, the hemolytic activity of venom from tentacles of C. nozakii and factors affecting its activity were assayed. The HUso （defined as the amount of protein required to lyse 50% of erythrocytes） of the venom against dove and chicken erythrocytes was 34 and 59 gg/mL, respectively. Carboxylmethyl chitosan and glycerol could increase hemolytic activity at concentrations greater than 0.06% and 0.2 mol/L, respectively.

Aquatic Toxicities of Three Aryloxyphenoxypropanoic Acid Herbicides on Cyanobacterium Microcystis aeruginosa

Pesticides will be released into aquatic systems after application in agriculture or industry. AOPPs （aryloxyphenoxypropanoic acids） herbicides, including fenoxaprop, quizalofop-P-ethyl and haloxyfop-methyl, can pose aquatic toxicity on cyanobacterium M. aeruginosa （Microcystis aeruginosa）. The inhibition percentages of the biomass of M. aeruginosa exposure to 10 mg＇L-I fenoxaprop, quizalofop-P-ethyl and haloxyfop-methyl on day 7 were 23.13%, 7.55%, and 7.56%, respectively. Protein content was also inhibited by the three AOPPs to fenoxaprop is the most toxic, followed by quizalofop-P-ethyl varying degrees. The growth and protein content results showed that and haloxyfop-methyl. It indicates that both the biomass and the protein content can be served as an indicator for evaluating the toxicity of the three chemicals. Growth rates of M. aeruginosa exposure to fenoxaprop are also the most significantly different compared to the control, which means that fenoxaprop is the most toxic among the three compounds. Results from this study may provide insights for evaluation of environmental risks of AOPPs. In addition, such insights will be helpful for guiding the application of AOPPs in agriculture.

Development of emergency water quality standard for Cr^(6+) and Hg^(2+) in Liao River basin

The acute toxicity data of Cr＋ and Hg2＋ to the aquatic organisms in Liao River basin was collected and screened. Calculated results of criteria values using popular species sensitivity distribution （SSD） methods were evaluated through data analysis. The comprehensive methodology of emergency water quality standards （EWQSs） was established on the basis of the SSD method of Australia and New Zealand according to the evalu- ation results. The affected fractions of the aquatic organisms were set to be 5 %, 15 %, 30 % and 50 %, corre- sponding to the risk grades of Ⅰ,Ⅱ,Ⅲ and IV, and four-grade EWQSs, respectively. The EWQSs for Cr6＋ and Hg2. in the Liao River were derived and the corresponding risk indicators were also proposed. The results showed that the four-grade EWQSs for Cr6＋ were 2.85 μg/L, 21.0 μg/L, 161 μg/L and 797 μ/L, respec- tively, and the risk indicators were daphnia （grade Ⅱ ）, shrimp （grade Ⅲ）, and the bighead fish or tadpole （grade IV）. The four-grade EWQSs for Hg2＋ were 0.59 μg/L, 2.32 μg/L, 6.25 μg/L and 15.6 μg/L, respective- ly, and the risk indicators were crucian carp or daphnia （grade Ⅱ）, shrimp （grade Ⅲ）, and worm or crab （grade IV）. The results provided valuable information for the risk analysis of sudden ambient water environmen- tal pollution accident.

Genotoxicity biomarkers in aquatic bioindicators

Pollution of the aquatic environment is an ever-growing problem, as waters are the ultimate sink for the large number of xenobiotics from multiple sources. DNA damaging agents have a significant ecological relevance since they are implicated in many pathological processes and exert effects beyond that of individual being active through following generations. A large number of methods have been applied to evaluate genotoxic damage in different aquatic species. Comet assay, as method for de- tecting DNA alterations, and micronucleus test, as an index of chromosomal damage are the most widely applied and validated methods in field studies. These methods were applied in different vertebrate and invertebrate aquatic species, but only mollusk and fish species have been employed in routine biomonitoring programs. Mussels, due to their widely geographical distribution and the suitability for caging represent the bioindicator of choice in field studies. Mytilus species is the most used marine mussel. The use of fish is limited to specific geographic areas. The present review mainly focuses on the application of comet assay and micronucleus test in mussels. A number of biomonitoring studies in mussels, using comet assay or micronucleus test, revealed exposure to different classes of genotoxic compounds with a good discrimination power. The different evidence from the two as- says, reflects different biological mechanisms for the two genetic endpoints, DNA damage and chromosomal damage, suggesting their combined application in the field. Different endogenous and exogenous factors have been shown to modulate the genotoxic responses in mussels, acting as confounding factors in environmental monitoring. The use of standardized protocol for caging, sampling and genotoxity evaluation is critical in biomonitoring studies. The use of a multimarker approach coupling genotoxicity biomarkers with physiological and biochemical factors allows to have a complete picture of the environmental pollution [Current Zoology 60 （2）： 273-284, 2014].

Acute toxicity study of Aspidopterys obcordata aqueous extract in Sprague-Dawley rats

OBJECTIVE: To examine the acute toxicity of an aqueous extract of Aspidopterys obcordata(A. obcordata) in Sprague Dawley rats.METHODS: The rats were orally administered a dose of 5000 mg/kg body weight and observed continuously for 6 h and then daily for 14 days. Control rats were administered distilled water. The effect of the extract on general behavior, body weight, and food and water intake were measured.After 14 days, the rats were sacrificed and their organs(liver, heart, spleen, lungs, kidney, adrenal glands, ovaries, and testes) were removed for macroscopic examination. The body and organ weights in addition to hematology(e.g., hemoglobin and white blood cell counts) and clinical blood biochemistry(e.g., albumin and bilirubin) were also examined.RESULTS: There were no deaths recorded, and the rats treated with A. obcordata showed no signs of toxicity. All measured parameters in rats treated with A. obcordata were unaffected when compared with those in control rats. The acute toxicity(LD_(50))was estimated to be > 5000 mg/kg body weight.CONCLUSION: Our results demonstrate the safety of an acute oral administration of an aqueous extract of A. obcordata in rats and indicate that future subacute and long-term toxicity testing of A. obcordata is warranted.