土壤重金属污染对蚯蚓的急性毒性效应研究

测定了草甸棕壤条件下 ,Cu、Zn、Pb、Cd单一 /复合污染对蚯蚓的急性致死及亚致死效应 .结果表明 ,Cu、Pb浓度与蚯蚓死亡率显著相关 (α=0 .0 5 ,RCu=0 .86 ,RPb=0 .87) ,Cu浓度与生长抑制率显著相关 (α=0 .0 5 ,RCu=0 .84) ,其他供试重金属浓度与蚯蚓死亡率和生长抑制率相关性不显著 .蚯蚓个体对重金属毒性的耐受程度差别较大 .其毒性阈值 (引起个体蚯蚓死亡浓度 )分别为 :Cu 30 0mg·kg-1,Zn 130 0mg·kg-1,Pb 170 0mg·kg-1,Cd 30 0mg·kg-1.LC50 分别为 :Cu 40 0～ 45 0mg·kg-1,Zn15 0 0～ 190 0mg·kg-1,Pb2 35 0～ 2 40 0mg·kg-1,Cd 90 0mg·kg-1.在Cu、Zn、Pb、Cd单一污染引起 >10 %蚯蚓死亡的浓度下 ,复合污染导致 10 0 %蚯蚓死亡 ,表明复合污染极强的协同效应 .     

重金属复合污染对小麦种子根活力的影响

应用二次回归旋转设计法,以小麦种子为材料,研究了水培条件下重金属复合污染对其根生长及活力的影响;借助回归分析建立了相应的数学模型,分析了Cu、Zn、Cd和Pb4种重金属对根活力的毒性、两两重金属问的联合作用以及各重金属的边际毒性效应．结果表明重金属对根活力的影响顺序为Pb＞Cu＞Cd＞Zn;Cu与Cd、Cu与Zn、Zn与Cd以及Cd与Pb元素间的互作效应显著;在0-20mg.L^-1浓度范围内,Cu和zn两元素在最小浓度时的边际效应值最大,Cd和Pb两元素的边际效应最大值却出现在最高浓度处．     

重金属对土壤中小麦种子发芽与根伸长抑制的生态毒性

测定了4种土壤（红壤、草甸棕壤、暗棕壤和栗钙土）条件下,Cu,Zn,Pb和Cd单一污染对小麦种子发芽与根伸长抑制主及其复合污染效应（暗棕壤条件下）。结果表明,同一浓度下,重金属对小麦根伸长抑制率均明显大于对种子发芽抑制率,植物根对金属污染的生态毒性比种子发芽敏感,土壤有机质和土壤N含量与Cu,Zn,Pb和Cd污染对小麦根伸长抑制率显著负相关（R^2OR=0.91,R^2K-N=0.92),土壤PH和阳离子交换量与Cu,Zn,Pb和Cd污染对小麦根伸长抑制率的相关性不显著（R^2PH=0.62,R^2CEC=0.60),在单一污染对小麦根伸长为刺激作用浓度（较低浓度）或为抑制作用浓度下（较高浓度）,复合污染均表现为协同作用。^     

4种重金属离子对多刺裸腹溞的联合毒性效应

在研究了铜、铅、镉和锌4种单一因子对多刺裸腹溞（Moina macrocopa）急性毒性作用基础上,采用Marking 相加指数法研究了联合毒性效应.实验结果表明：4种重金属离子的毒性大小依次为Cd2＋＞Cu2＋＞Pb2＋＞Zn2＋,对多刺裸腹溞48h的LC50分别为0.0076mg/L,0.0306mg/L,0.0532mg/L,0.3568mg/L;Pb2＋-Cu2＋-Cd2＋、Pb2＋-Zn2＋-Cd2＋3种离子和Cu2＋-Pb2＋-cd2＋-Zn2＋4种离子共存时的毒性效应表现为拮抗作用;Cu2＋-Zn2＋-Cd2＋和Pb2＋-cu2＋-Zn2＋共存时的联合毒性较为复杂,三者浓度比1：1：1时表现为协同作用,而毒性比1∶1：1时在24h内表现为协同作用,至48h时为拮抗作用.     

6种重金属对赤子爱胜蚓的急性毒性效应与风险评价

【背景】近年来,土壤重金属污染问题日益凸显,对生态环境、食品安全和人体健康构成了严重威胁,其急性毒性尚未明确。【方法】采用滤纸接触法和人工土壤法测定了铜(Cu2+)、锌(Zn2+)、镍(Ni+)、镉(Cd2+)、铅(Pb2+)和锰(Mn2+)等6种重金属对赤子爱胜蚓的急性毒性效应,并参照欧盟指令91/414/EEC标准评价了其环境风险。【结果】滤纸接触法48h测定结果表明,6种重金属对蚯蚓的LC50为3.17(2.53～3.81)～90.42(69.45～140.47)μg.cm-2,其毒性次序为Cu2+>Zn2+>Ni+>Cd2+>Pb2+>Mn2+。人工土壤法14d测定结果表明,6种重金属对蚯蚓的LC50为1347(1236～1453)～6936(6144～8930)mg.kg-1,其毒性次序为Cu2+>Cd2+>Ni+>Zn2+>Mn2+>Pb2+。风险评价结果显示,Cu2+、Zn2+、Ni+、Cd2+、Pb2+和Mn2+等6种重金属的暴露比(toxicity/exposureratio,TER)分别为3.37、4.46、8.68、1428、13.87和5.85。【结论与意义】6种重金属对土壤动物蚯蚓均具有潜在的毒性效应。Cu2+、Zn2+、Ni+、Mn2+等4种重金属对赤子爱胜蚓存在急性毒性风险,而Cd2+和Pb2+对赤子爱胜蚓的急性毒性风险水平是可接受的。该评价结果可为我国制定基于风险的土壤环境质量标准提供依据。     

四种重金属对中国鲎(Tachypleus tridentatus)胚胎发育的影响

分析了不同离子浓度的Zn、Pb、Cu、Cd对中国鲎胚胎发育的影响.结果表明①4种金属离子浓度≤渔业水域水质标准浓度4倍时,对中国鲎胚胎发育无明显毒性效应;≥渔业水域水质标准浓度8倍时,Cd离子和Cu离子对中国鲎胚胎发育无明显影响,而Zn离子组Pb离子组胚体发育随离子浓度提高而卵径变小,发育速度下降;②浓度为1.6mg/L时,Zn和Pb离子组胚胎致畸率分别为44%和58%,Pb离子组胚体孵化率仅2.67%;③4种重金属对中国鲎胚胎发育的毒性效应表现为Pb＞Zn＞Cu=Cd;④中国鲎胚胎对重金属有蓄积作用,蓄积效应随金属种类不同而异.     

几种重金属离子对光倒刺鲃胚胎发育的毒性

在水温24～26℃条件下,采用半静止式生物毒性实验法,分析了不同浓度的Cu2 、Zn2 、Cd2 对光倒刺纪(Spinibarbus hollandi)胚胎发育的毒性效应,以及Cu2 -Cd2 、Pb2 .-Zn2 对光倒刺钯胚胎发育的联合毒性效应.结果表明,在各种不同浓度的重金属离子溶液实验组中胚胎的孵化率均较低,与对照组差异极显著(P＜0.01);各种重金属在胚胎发育过程中引起各种畸形;除了Cu2 ≥0.10 mg/L、Cu2 -Cd2 ≥0.50 mg/L、Pb2 -Zn2 ≥2.00 mg/L实验组会促进胚胎发育速率外,其余各种离子溶液的各实验组均在不同程度上减慢胚胎的发育速率.3种重金属对光倒刺(鱼巴)胚胎发育的毒性效应表现为Cu2 ＞Cd2 ＞Zn2 .Cu2 、Cd2 、Zn2 、Cu2 .-Cd2 混合、Pb2 -Zn2 混合离子对光倒刺(鱼巴)胚胎发育的安全浓度分别为0.009 ms/L、0.065 mg/L、0.023mg/L、0.011mg/L、0.523 mg/L.Cu2 与Cd2 对光倒刺(鱼巴)胚胎的联合毒性为拮抗作用.     

厦门海域两头中华白海豚体内微量元素的积累

对2004年4月在厦门海域搁浅死亡的两头中华白海豚（Sousa chinensis）进行了肝脏、胰、胃、肾、肠、肺、肌肉、心脏等多组织微量元素锌（Zn）、铜（Cu）、汞（Hg）、铅（Pb）、镉（Cd）和砷（As）浓度的测定。两豚各组织总体上必需元素Zn、Cu浓度高于有毒元素Hg、Pb、Cd和As。XM20040430体内特别高的Zn、Hg、Pb、Cd浓度分别出现于皮肤（500μg/g干重）、肝脏（255μg/g干重）、肺（13.0μg/g干重）和肾（2.82μg/g干重）中,而Cu和As在各组织中的浓度较为相似。XM20040429体内仅肝脏中Zn（448μg/g干重）和Cu（52.0μg/g干重）的浓度远高于其他组织。虽然两海豚微量元素的总体积累多低于急性毒性水平,但有毒元素Hg、Pb、Cd、As的明显检出和XM20040429肝脏中异常高的Zn浓度均显示出进一步研究微量元素慢性胁迫效应的必要性。结果还显示厦门港海域近年来Hg、Cd、Pb污染未见减轻,As也明显检出,必须引起高度重视。今后有关水生哺乳动物中As积累的研究也有待加强。     

Pb和Cd单一及复合胁迫条件下溪荪(Iris sanguinea)生长及金属离子积累特征分析

采用水培法,对Pb和Cd单一及复合胁迫(500 mg·L-1Pb、25 mg·L-1 Cd、500 mg·L-1pb-25 mg·L-1Cd)条件下溪荪(Iris sanguinea Donn ex Horn.)幼苗不同部分的生长及Pb、Cd、Zn、Cu、K和Na积累状况进行了研究.结果显示:在Pb单一胁迫条件下,溪荪幼苗地下部分干质量较对照降低了18.2％,地上部分干质量和耐性指数均与对照无显著差异;在Cd单一胁迫条件下,地下部分与地上部分的干质量较对照分别降低了16.4％和14.1％,耐性指数降低了7％;在Pb-Cd复合胁迫条件下,溪荪幼苗不同部分的干质量以及耐性指数均与对照无显著差异.在Pb单一及Pb-Cd复合胁迫条件下,幼苗不同部分的Pb含量均明显高于对照,Pb单一胁迫处理组幼苗地上部分和地下部分的Pb含量分别比Pb-Cd复合胁迫处理组高19.8％和16.0％.在Cd单一及Pb-Cd复合胁迫条件下,幼苗不同部分的Cd含量均明显高于对照,Pb-Cd复合胁迫处理组幼苗地上部分和地下部分的Cd含量分别为Cd单一胁迫处理组的2.02和5.74倍.经Pb和Cd单一及复合胁迫后,幼苗不同部分的Zn、Cu和Na含量均明显高于对照,而K含量则低于对照;地上部分的Zn、K和Na含量均高于地下部分,但Cu含量在幼苗不同部分的变化趋势则有所不同.比较结果表明:Pb-Cd复合胁迫对溪荪幼苗的Pb积累有促进作用、对Cd积累有抑制作用,表现出拮抗作用;溪荪对Pb胁迫的耐性相对更强,对Pb和Cd及其他金属元素有一定的积累能力,可用于Pb污染环境尤其是湿地Pb污染环境的修复.     

甲胺磷、乙草胺和铜单一与复合污染对蚯蚓的毒性效应研究

以赤子爱胜蚓(Eisenia foetida)为例,通过滤纸急性毒性试验法研究了东北黑土区普遍存在的3种农用化学品甲胺磷、乙草胺和Cu对蚯蚓的单一与复合毒性效应．单一实验结果表明,三者对蚯蚓均有毒性,它们的毒性顺序为乙草胺＞甲胺磷＞Cu,半致死浓度分别为：0．307、0．708和118．70mg.kg^-1;同时通过观察可知,乙草胺与Cu以皮肤渗入蚯蚓体的毒性效应较甲胺磷明显．复合毒性实验结果表明,低浓度Cu与高浓度Cu对甲胺磷的毒性均有增强作用;低浓度Cu对乙草胺的毒性有削弱作用,但高浓度Cu对乙草胺的毒性有增强作用．可见,三者对土壤生态系统生态安全性和土壤健康质量存在潜在危害,同时这几种污染物的共存进一步加大了潜在危害性,且复合毒性效应与各组浓度组合密切相关．     

Metal Speciation and Contamination in Dredged Harbor Sediments from Kaohsiung Harbor,Taiwan

The status of metal speciation and contamination of sediments in Kaohsiung Harbor, Taiwan, was evaluated by a five-step sequential extraction procedure (exchangeable, carbonate, Fe–Mn oxides, organic matter, and residual). Eleven dredged sediment samples from various locations in the harbor were characterized in terms of heavy metals, grain size, and total organic carbons. Results showed that Hg, Pb, Cd, Cr, Cu, Zn, Ni, and Mn had different species composition patterns. The degree of sediment contamination was determined for an individual contamination factor (ICF) and a global contamination factor (GCF); results showed that Kaohsiung Harbor had a high potential risk for Pb, Cd, Cr, and Cu. Based on GCF values, the results showed that those stations, located in the vicinity of the river mouth, fish port, and industrial sites, contributed high potential risk to Kaohsiung Harbor. The potential risk of heavy metals to the environment was assessed for risk using the risk assessment code (RAC) and results showed that Pb, Cd, Zn, and Mn generally created a medium to high risk, and Hg, Cr, Cu, and Ni generally created a low to medium risk.     

贵州兴仁煤矿区农田土壤重金属化学形态及风险评估

为了解煤矿区周边农田土壤重金属污染状况,采集了贵州省兴仁县某典型煤矿区农田土壤样品64份,测定了土样中重金属(As、Cr、Pb、Zn、Cd、Hg、Cu、Ni)总量及各形态含量,采用单因子指数法、潜在生态风险指数法(Hkanson法)和风险评估编码法(RAC)对研究区主要土壤利用类型(水稻土、薏米地、植烟土和菜园土)中重金属进行潜在生态风险评估和环境风险评价.结果表明： 不同利用类型土壤中重金属含量除Zn外,其他元素均明显超过贵州省背景值.单因子指数法评价结果表明,As、Pb、Hg和Cu污染较为严重,均属重度污染.形态分析表明,土壤中重金属形态构成差异明显,酸可提取态As、酸可提取态Cd所占比例较高;Cr、Zn、Cu、Ni主要以残渣态为主;Pb主要以可还原态和残渣态为主;而Hg的酸可提取态、可还原态、可氧化态均占有相当比例,三者之和大于55%.重金属可利用度大小顺序为:As(63.6%)>Hg(57.3%)>Cd(56.4%)>Pb(52.5%)>Cu(45.7%)>Zn(32.8%)>Ni(26.2%)>Cr(13.2%).潜在生态风险指数表明,各类型土壤潜在生态风险(RI)〖JP2〗为:菜园土(505.19)>薏米地(486.06)>植烟土(475.33)>水稻土(446.86),均处于较高风险.风险评估编码法结果显示,As在水稻土、薏米地及植烟土中均处于高风险,在菜园土中处于中等风险;Cd、Hg均处于中等风险,Cr、Pb、Zn、Cu和Ni均处于低风险.因此,对该区域农田土壤进行管控时应重点考虑As、Cd和Hg污染.     

某农药工业园区周边土壤重金属含量与风险评价

以苏南某农药工业园区周边30km2区域为研究区,采用同心圆法采集土壤样品183个,分析了农药工业园区周边土壤Cd、Cr、Cu、Ni、Pb、Zn、Hg和As8种重金属含量、空间变异性、来源及潜在风险.结果表明:以自然背景值为评价标准,研究区表层土壤Hg、Cu、Cd和Pb平均含量超过自然背景值,其中Hg和Cu含量最高;以国标二级标准为评价标准,土壤Cd、Cr、Ni、Pb、Zn、As6种重金属的单项污染指数平均值均小于1,Hg和Cu分别为1.59和1.05.在农药工业园区周边土壤重金属污染较重的东南方向和西北方向,随着与园区距离的增加,土壤Cd、Ni、Pb、Cr、As、Hg、Zn和Cu含量先上升、后下降、再趋于平稳.通过分析农药工业园区周边土壤重金属综合污染指数发现,距离园区约200～1000m周边土壤污染的风险较大,而1000m以外逐渐达到安全范围.利用地统计学和GIS相结合进行分析发现,8种重金属污染指数有明显的空间变异.依据相关分析与主成分分析结果推测,Zn、Ni、Cr、Pb和As主要来源于成土母质,而Hg、Cu和Cd主要与人类活动有关.     

Spatial distribution,contamination levels,sources, and potential health risk assessment of trace elements in street dusts of Urumqi city,NW China

Abstract

A total of 83 dust samples were collected from the streets of Urumqi city in NW China and analyzed for the concentrations of As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, and Zn elements. The spatial distribution, contamination levels, main sources, and potential health risks of these trace elements were determined based on geostatistical analysis, geo-accumulation index, multivariate analysis, and the health risk assessment model introduced by the USEPA, respectively. The obtained results indicate that the average concentrations of Cd, Cr, Cu, Hg, Ni, Pb, and Zn exceed the corresponding background values determined in Xinjiang soils by factors of 2.0, 1.35, 1.38, 8.24, 1.28, 2.09, and 3.26, respectively. The spatial distribution patterns of the nine trace elements in street dust were found to be substantially heterogeneous, and the contamination level decreased in the following order: Hg?>?Zn?>?Pb?>?Cd?>?Cr?>?Cu?>?As?>?Ni?>?Mn. Based on the identified concentrations, the collected dust samples were found to be moderately polluted by Hg, and not polluted by As, Cr, Cu, Mn, and Ni. The remaining elements, Cd, Pb, and Zn lie on the borderline between non-pollution and moderate pollution levels. Furthermore, it was shown that Mn and Zn in street dusts originate from both, natural and anthropogenic sources, while As, Cd, Cr, Cu, Hg, Ni, and Pb are mainly produced by anthropogenic sources. Overall, the carcinogenic and non-carcinogenic health risks of the analyzed elements, instigated primarily by oral ingestion of street dusts, were found to be within the acceptable range for both, children and adults. As and Cr are the main non-carcinogenic elements, whereas Cr is the major carcinogenic element among the investigated dust-bound metals in the study area.     

Sources,distribution and temporal variability of trace metals in the Thames Estuary

Water and intertidal sediment samples were collected from 28 stations along the Thames Estuary, from the tidal limit to the outer estuary. Surveys were conducted in 1997, 1999 and 2001 to assess spatial distributions and short-term variability. Highest concentrations of trace metals in water coincided with high turbidity in the mid-estuarine region, although the particle-associated fraction varied from 22% (As) to 95% (Pb). Theoretical dilution line (TDL) plots showed that dissolved metals were largely derived from a combination of diffuse (sediment desorption) and localised point sources (outfalls, industry). Dissolved Cu and Zn both exceeded environmental quality standard (EQS) levels during the survey period. The majority of sediment metals showed common distributional patterns, with increasing concentrations upstream. This increase was greatest for pollutant metals: Ag, Cd, Cu, Hg, Pb and Zn. Partial extraction of sediment metals with 1 M HCl showed that >50% of Ag, Cd, Cu, Mn, Pb and Zn were potentially bioavailable and that the proportion of bioavailable sediment metals also increased upstream. The majority of sediment metal concentrations exceeded Interim Sediment Quality Guideline threshold effects levels (TELs) over much of the estuary. Sediment concentrations of Cu, Hg, Pb and Zn also exceeded probable effects levels (PELs) at many estuarine sites. Despite improvements in recent years, the Thames Estuary remains chronically contaminated with a range of metals.     

刺楸年轮中重金属含量动态变化及富集特性

为探索刺楸对受污染土壤重金属的富集和修复效应, 以南京栖霞山的乡土树种刺楸及其根际周边土壤为研究对象, 截取其根基部年轮盘及根际土壤样本, 采用ICP-AES法测定年轮及土壤样本中重金属(Cu、Cd、Cr、Mn、Ni、Pb、Zn)元素含量。结果表明: 栖霞山样地中的土壤受Mn、Pb和Zn污染最为严重, 存在Cu、Cd、Mn、Pb、Zn元素的高度复合污染, Cd、Cr、Cu、Ni、Zn在土壤和年轮中存在相关性, Mn和Pb则没有表现出明显的相关性; 刺楸修复受Cd、Mn、Pb、Zn污染的土壤效果并不显著, 更适用于Cr、Cu、Ni污染的土壤修复; 鉴于Cu元素含量变化特征, 刺楸也可以作为反映当地污染历史的记录载体; 刺楸年轮中的重金属元素之间存在交互作用, 其中Cd与Zn元素含量高度相关(r=0.984, p<0.01), 在刺楸年轮吸收重金属元素的过程中, Cu与Cd、Cr、Mn、Zn元素具有协同作用, Mn元素对其他元素有一定的拮抗作用。     

匍茎翦股颖对Cu2+、Zn2+、Cd2+与Pb2+ 胁迫的生长响应与阈限浓度

采用砂培法,研究了匍茎翦股颖对Cu2+、Zn2+、Cd2+与Pb2+胁迫的生长响应及阈限浓度,结果表明:种子萌发率随着4种重金属浓度的增加而下降。对株高的影响是当重金属浓度小于100mg/L时会促进株高生长,高于100mg/L则产生抑制作用。Cu2+显著抑制根系生长,并随浓度的增加抑制效应愈加显著;在Cu2+浓度为600mg/L时匍茎翦股颖的根长比对照下降了93.75%。Cu2+、Zn2+、Pb2+浓度小于200mg/L时会促进地上生物量的增加,但高于200mg/L时,地上生物量会随着3种重金属的增加而减少。Cu2+、Zn2+浓度小于100mg/L或Cd2+、Pb2+浓度小于200mg/L会增加叶绿素的含量,高浓度会降低叶绿素的含量;Cd2+在浓度为600mg/L时显著降低叶绿素含量,与对照相比,下降了43.55%。匍茎翦股颖生长的综合效应分析表明,匍茎翦股颖对Cu2+胁迫最敏感,具有较低的阈限浓度,而Zn2+胁迫对匍茎翦股颖的生长影响最小,阈限浓度相对较高。     

Concentrations and interactions of selected essential and non-essential elements in ringed seals and polar bears of arctic Alaska.

In this study, we evaluated concentrations of twelve essential and non-essential elements (As, Cd, Co, Cu, Pb, Mg, Mn, Hg, Mo, Se, Ag, and Zn) in tissues of ringed seals (Phoca hispida) and polar bears (Ursus maritimus) of arctic Alaska (USA). All samples were collected between 1995-97 in conjunction with subsistence harvests. The essential elements are reported to help develop reference ranges for health status determination and to help assess known or suspected interactions affecting toxicoses of cadmium (Cd) and mercury (Hg). In some tissues, Cd, Hg, and selenium (Se) were present at concentrations that have been associated with toxicoses in some domestic animals. Nevertheless, tissue levels of all elements were within ranges that have been reported previously in other pinnipeds and polar bears. Significant associations included: Cd with Zn or Cu; Cu with Zn or Ag; and Hg with Se, Zn, or Cu. This study found hepatic Hg:Se molar ratios to be lower than unity and different between the two species. Based upon significant differences in mean tissue elemental concentrations for polar bear versus ringed seal, we concluded that biomagnification factors (bear/seal) were significant for: Cu in liver and muscle; Pb in kidney; Se in kidney and muscle; Zn in liver and muscle; and Hg in liver. Possible explanations for observed elemental correlations (i.e., interactions) and ancillary mechanisms of Cd and Hg detoxification are discussed.     

五种重金属离子对克氏原螯虾（Procambarus clarkiai）的急性毒性作用研究

采用静水生物法、充气和恒温法研究了5种重金属离子对克氏原螯虾的急性毒性作用,并以直线内插法得出了24 h、48 h、72 h和96 h的半致死量（LD50）.研究结果表明：重金属离子的毒性顺序由大到小依次为：Hg2＋、Cd2＋、Cu2＋、Pb2＋和Zn2＋.根据毒性分级标准,5种重金属离子对克氏原螫虾均为高毒物,其安全质量浓度依次为：0.0143 mg/L、0.0322 mg/L、0.0401 mg/L、0.1995 ms/L和0.2795 mg/L.以浓度对数和死亡率进行回归分析,分别得出了5种重金属离子对螯虾24 h、48 h和96 h的回归方程.