常见拟除虫菊酯和有机磷农药对鱼类的急性及其联合毒性研究

以崇明岛前卫村中心湖中鲫鱼、鲤鱼、鲢鱼及泥鳅作为实验动物.进行了氯氰菊酯(原药和商品)、氰戊菊酯(原药和商品)、毒死蜱(原药和商品)、甲氰菊酯(商品)、溴氰菊酯(商品)、辛硫磷(商品)以及乙酰甲胺磷(商品)7种供试农药对实验鱼种的急性毒性及联合毒性实验,并检测了前卫村中心湖水体中18种有机磷农药和4种拟除虫菊酯农药,其中检出了1种有机磷农药(毒死蜱)和3种拟除虫菊酯农药(氰戊菊酯、氯氰菊酯、甲氰菊酯).结果表明,在单一农药急性毒性实验中,鲤鱼对供试农药表现较敏感,其次是鲫鱼和鲢鱼,而泥鳅对农药的耐药性最强;7种供试农药中,拟除虫菊酯农药相对于有机磷农药表现出较高的急性毒性,其实验鱼种的半数致死浓度(LC60)皆在μg/L级;对拟除虫菊酯农药(氯氰菊酯,氰戊菊酯)与有机磷农药(辛硫磷、乙酰甲胺磷)进行的联合毒性实验结果表明,除了暴露时间为24、48 h时氰戊菊酯与辛硫磷混配对鲢鱼的毒性实验表现为协同作用外,其余皆为拈抗作用.     

石灰钝化法原位修复酸性镉污染菜地土壤

在湖南省湘潭县酸性(pH=5.47±0.64)镉污染((1.06±0.08)mg·kg~(-1))菜地,进行为期1年的田间修复实验。研究施用石灰类钝化剂(石灰石或生石灰)对菜地土壤镉(Cd)的有效性、当地常见蔬菜可食部位Cd含量的影响,分析蔬菜种植过程中农业投入品对表层土壤(20 cm)Cd积累的影响,确定Cd污染菜地蔬菜安全生产的措施。结果表明:与对照相比,施加4 500 kg·hm~(-2)CaCO_3或3 000 kg·hm~(-2)CaO分别使土壤pH升高了1.48和1.73,土壤有效态Cd含量分别降低了87.8%和78.1%;叶菜类、根茎类、茄果类和豆类蔬菜可食部位Cd含量分别降低了5.9%～70.5%、59.8%～65.8%、4.0%～50.0%和35.0%～76.4%,但施用4 500 kg·hm~(-2)CaCO_3或3 000 kg·hm~(-2)CaO不能使叶菜类、茄果类蔬菜中Cd含量降低到相应的国家食品安全标准限值(叶菜类蔬菜,0.2 mg·kg~(-1);茄果类蔬菜,0.05mg·kg~(-1))以下;蔬菜种植过程中施用的基肥、灌溉水、CaCO_3或CaO不会导致表层土壤Cd含量增加。在酸性Cd污染菜地施用CaCO_3或CaO、并种植低Cd积累蔬菜,可以实现蔬菜的安全生产。     

贵阳南部近郊蔬菜重金属污染状况及健康风险评估

于贵阳花溪区蔬菜种植基地及零星菜地采集叶菜类、茎菜类和果菜类样品及对应土壤样品,测定土壤与蔬菜样品中Zn、Cd、Pb和Cu含量,分析土壤理化性质、土壤重金属全量、有效态含量与蔬菜中重金属含量之间的关系,通过污染指数和暴露风险健康评估指数分析城郊蔬菜中重金属污染状况以及摄入人群的健康风险。结果表明:部分菜地土壤样品Zn、Cu含量超出农用地土壤污染风险筛选值,超标率分别为8.82%、11.76%;蔬菜中重金属含量主要取决于土壤重金属有效态含量;研究区蔬菜均处于清洁水平,但有8.82%的蔬菜样品Pb处于Ⅱ级警戒值,且均为叶菜;Pb是叶菜类暴露健康风险的主要元素,而Cu是茎菜类与果菜类暴露健康风险的重要元素;蔬菜重金属对儿童和成人的危害指数均小于1.0,表明食用该地区的蔬菜不会对人体健康产生不良影响。     

农药毒死蜱的生态风险及其微生物修复技术研究进展

毒死蜱是替代甲胺磷和对硫磷等高毒农药的高效有机磷杀虫剂,在世界范围得到广泛使用.但是,环境毒理学研究发现,毒死蜱对生态环境具有潜在的危险性,甚至被认为具有干扰内分泌的功能,许多国家对毒死蜱在农产品中的残留量有严格的规定.因此,深入研究毒死蜱的生态风险问题是当务之急.对国内外关于毒死蜱的残留活性、生态毒理、降解机制以及生物修复等方面的研究进行了综述,以期对毒死蜱的合理管理和使用提供科学依据.     

滇池疏浚底泥中重金属在4种蔬菜中的累积效应及其风险评价

滇池疏浚底泥富含有机质和N、P等营养成分,农用可提高土壤保水肥能力,有利于植物生长发育,但是存在重金属污染问题。通过盆栽及田间实验,对生菜、白菜、棒菜和萝卜4种蔬菜施用疏浚底泥作为有机肥进行种植,分析疏浚底泥农用后,其重金属含量对蔬菜的影响,并对其进行风险评价。结果表明,盆栽实验中,应将底泥的施用量控制在5%(0.05 kg·kg~(-1))以内。田间实验中,叶菜类蔬菜种植应将底泥的施用量控制在1.6 kg·m-2以下,块茎类蔬菜种植应将底泥的施用量控制在2.4 kg·m-2以下。风险评价采用富集系数(BCF),以及内梅罗污染指数。盆栽实验中叶菜类蔬菜BCF均为CdPbZnCu,而块茎类组分BCF均为CdZnPbCu;田间实验中叶菜类蔬菜BCF均为ZnCdPbCu,茎块类蔬菜BCF为ZnCdCuPb。化学致癌物Cd引起的平均健康风险均低于国际辐射防护委员会(ICRP)推荐的最大的终生可接受风险水平;而非化学致癌物Pb、Zn、Cu引起的健康风险以Zn最大,Pb次之,Cu最小,且所有非致癌物健康风险均远低于英国皇家协会、瑞典环境保护局及荷兰建设环境部等推荐的终生可接受风险水平。     

铜绿山矿区菜地土壤重金属污染特征

以铜绿山矿区菜地为研究对象,测定了土壤和蔬菜中Cu、Zn、Pb、Cd 4种重金属的含量,分析了土壤-蔬菜体系重金属的污染特征和蔬菜对重金属的富集能力。结果表明:矿区菜地土壤中重金属Cu、Zn、Pb、Cd的污染因子分别为10.63、1.12、1.10、0.06,表明Cu污染非常严重,Zn、Pb属轻度污染,Cd无污染;参考《食品中污染物限量》(GB 2762—2017)、《食品中铜限量卫生标准》(GB 15199—94)以及《食品中锌限量卫生标准》(GB 13106—91),蔬菜中Cu、Zn污染较严重且具有普遍性;蔬菜中Cd含量虽均未超出食品安全限值,但明显高于蔬菜根部土壤中的Cd含量;叶菜类、根茎类蔬菜中Pb均未超标,瓜果类蔬菜中Pb超标;蔬菜可食部位对重金属的富集能力为CdZnCuPb;蔬菜中重金属含量与土壤重金属含量总体表现出较弱的相关性,表明蔬菜中重金属的积累不完全决定于土壤重金属的含量,还与土壤中重金属的生物有效性、环境行为及其他环境因素有关。     

中国化肥农药施用总体特征及减施效果分析

利用文献数据和统计资料,分析了中国1990—2016年化肥农药施用的总体状况,包括施用总量、施用结构和施用强度的历史变化特征,重点分析了2014—2016年全国各省份化肥农药施用总量和施用强度的变化特征,以及2015年和2016年全国各省份化肥农药"双减"实施状况。1990—2016年,中国化肥农药施用总量稳步上升,但结构不断变化,其中最显著的变化是复合肥使用占比逐年增加,新型高效低毒农药成为发展趋势。2014—2016年,全国化肥农药减施明显,其中2015年全国化肥施用总量增幅仅为0.4%,2016年化肥施用总量增幅为-0.6%,首次实现负增长;2015年和2016年,农药施用总量连续两年实现负增长,增幅分别为-1.3%和-2.4%。施用总量上,2015年全国实现化肥农药"双减"的省份共有10个,2016年增加到19个;施用强度上,2015年全国实现化肥农药"双减"的省份有11个,2016年增加到18个。2015年和2016年,总体上全国化肥农药施用强度减施效果优于施用总量减施效果,农药减施效果优于化肥减施效果。     

某废弃铅冶炼场地周边蔬菜重金属污染水平及来源解析

于某废弃铅冶炼场地周边菜地采集69份蔬菜样品,通过测定蔬菜样品中的As、Cd、Cr、Hg、Pb含量评价重金属污染水平,并对污染来源进行解析。结果表明,萝卜中As、Cd、Cr、Hg、Pb的整体水平分别为0.040、0.022、0.359、0.003、0.220mg/kg;白菜中的整体水平分别为0.026、0.022、0.307、0.004、0.158mg/kg;大葱中的整体水平分别为0.014、0.017、0.204、0.002、0.104mg/kg,蔬菜样品中Cr、Pb存在超过《食品安全国家标准食品中污染物限量》(GB 2762—2017)限值的现象,超标率分别为17.65%～46.15%、3.85%～86.77%;蔬菜中5种重金属的富集系数为CdHgPbCrAs,蔬菜中Cr、Pb为中度或重度污染,其中白菜比萝卜和大葱更易受到污染;工业排放源是周边地区蔬菜重金属含量的主要来源,其对萝卜、白菜和大葱重金属的贡献率分别为65.4%、35.5%、97.3%。     

天津地区不同茄子种植模式对土壤氮磷淋溶损失的影响

蔬菜种植具有水肥需求量大等特点,导致菜地土壤氮磷淋溶损失(以下简称淋失)风险较高。茄子作为中国主要的蔬菜种类之一,其种植地氮磷淋失问题不容忽视。为探索降低茄田土壤氮磷淋失风险的种植模式,采用田间渗滤池技术,对不同种植模式(茄子单作、茄子/小白菜间作、茄子/小白菜间作+黄花菜/矮化石榴植物篱、茄子/小白菜间作+柠条/沙棘植物篱)下菜地土壤淋溶液中氮磷含量进行监测,研究茄子不同种植模式对土壤氮磷淋失的影响。结果表明,在4种种植模式中,以茄子/小白菜间作+黄花菜/矮化石榴植物篱对TN、NO_3~-淋失拦截效果最佳,较茄子单作分别降低46.14%、51.62%;然而,不同种植模式对NH_4~+的淋失拦截无显著差异。与茄子单作相比,其他种植模式对TP的淋失拦截显著,其中以茄子/小白菜间作最佳,较茄子单作相比显著减少了40.80%。在茄子生产过程中,茄子/小白菜间作+黄花菜/矮化石榴植物篱能够有效降低土壤氮磷淋失风险,是适宜天津地区治理菜地氮磷淋失的一种有效措施,研究成果将为治理天津地区面源污染提供技术指导。     

福州市主栽蔬菜品种对砷的积累及健康风险

为阐明福州市主要蔬菜基地种植的蔬菜中砷积累特征与食用风险水平,对研究区域内蔬菜和对应土壤中砷含量进行了分析检测,采用Monte-Carlo模型法对蔬菜中砷引起的健康风险进行了评价,并探讨了蔬菜和土壤砷含量之间的相关性及不同品种、不同类别蔬菜之间积累砷的差异。结果表明:研究区内菜地土壤没有明显的砷超标,砷含量均未超出国家土壤二级标准(30 mg·kg~(-1));研究区内蔬菜安全状态很好,不存在明显的健康风险;蔬菜中砷与其对应土壤中砷之间无显著相关性;不同类别的蔬菜之间对于砷的累积存在差异性,蔬菜中砷的富集系数顺序为叶菜类根茎类瓜果类,其中茼蒿的富集系数最大,豌豆和辣椒的最小。     

浮萍生长及其除磷效率的影响因素的研究

磷是藻类增殖的限制因子,是引起水体富营养化的关键营养物质.有效除磷,能在很大程度上减轻水体的富营养化.利用浮萍科植物吸收转化污水中的营养物质引起了越来越多研究者的关注,但对浮萍科植物除磷效果的影响因素的研究相对较少.以少根紫萍(Spirodela oligorrhiza)为供试材料,以完全培养液为处理对象,研究了培养液pH、少根紫萍初始放养密度对其生长及除磷效率的影响.结果表明:少根紫萍能够耐受的最低pH在4左右,在pH＝5～9能正常生长,在pH＝6～8具有较高的TP去除率,最高去除率可达84.1%;少根紫萍的相对增长率随其初始放养密度的增加而降低,但其鲜重增长量、平均增长速率、TP去除率及平均TP去除速率均随着初始放养密度的增加而增加.     

基于客土灌木化技术的弃渣场生态治理

山区公路建设弃渣场常由石渣堆砌而成,其结构松散、孔隙率大、渗透性强,自然生态恢复极为困难.而客土培育技术常用于生态条件恶劣的区域生态治理.以湖北省宜昌某高速公路弃渣场为依托,应用客土灌木化施工工艺,以植被覆盖度和高度作为观测指标,开展了弃渣场生态恢复试验,主要研究灌木生长特点及其对土壤侵蚀的影响,提出适宜宜昌地区弃渣场生态治理的植被类型,对区域内弃渣场生态恢复工程有一定指导意义.     

模拟生态种植槽对雨水径流的净化

为减少环湖公路路面径流对洱海水质的影响,该研究选用土壤、锯末、沙子、砾石分层装填的生态型的路面径流收集、净化和输送系统-生态种植槽(其中混合填料层锯末与沙子的配比设置3种比例1∶3、1∶4、1∶5),研究该装置对模拟雨水的净化效果,并寻求最佳填充方式.结果表明,3组种植槽适合植物移栽、自然挂膜、低污染负荷启动方式;能稳定有效地去除COD、SS.运行期COD的平均出水水质优于地表水Ⅴ类水质,SS的平均去除率均高于80％.不同混合填料比种植槽对污水中COD的净化效果从高到低排序依次为:1∶5(锯末∶沙子)＞1∶4(锯末∶沙子)＞1∶3(锯末∶沙子),方差分析显示,3组种植槽系统间COD、SS去除率无差异(P＞0.05),考虑到锯末∶沙子为1∶5时的渗透效果差,故推荐锯末∶沙子为1∶4的种植槽供后续示范工程选用.     

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.