Tissue Injury and Cellular Immune Responses to Cadmium Chloride Exposure in the Common Mussel Mytilus edulis: Modulation by Lipopolysaccharide

The immunotoxic effects of cadmium (Cd) exposure in bivalves are poorly understood and whether or not stimulation of the immune system exacerbates Cd toxicity is unclear. The mussel Mytilus edulis was exposed to 20 or 50 μg/l total Cd for up to 11 days compared to no added Cd controls to assess immune and other physiological responses. Selected experiments were then repeated in the presence of a lipopolysaccharide (LPS) challenge with and without subsequent Cd exposure. Immune functions of hemocytes, hematology, hemolymph glucose and ion content, as well as superoxide dismutase (SOD) activity and organ pathology were measured. Cd accumulated mainly in digestive gland and gills and to a lesser extent in the adductor muscle. Exposure to 20 μg/l Cd alone caused a transient modulated of phagocytosis and increased neutral red retention (Kruskal–Wallis, p = 0.002). The higher Cd concentration also increased cytotoxicity, and decreased hemocyte count. Changes in hemolymph Na⁺, K⁺, and glucose were small or negligible. Histopathological examination showed tissue injuries consistent with inflammation and necrosis in the gills, digestive gland, and adductor muscle during Cd exposure alone. LPS injection alone and LPS + Cd caused an increase in the number of circulating hemocytes by the end of the experiment (Kruskal–Wallis, p = 0.01) and a transient rise in phagocytosis at day 4 (analysis of variance (ANOVA), p = 0.001). The LPS + Cd treatment also caused transient changes in neutral red retention and in the cytotoxicity of hemocytes compared to controls. Intracellular SOD activity did not change in hemocytes under any treatment. Tissue inflammation and pathology was greatly increased by the effect of Cd exposure with an LPS injection compared to either treatment alone. We conclude that immunostimulation with LPS can greatly increase Cd-related organ pathologies but does not necessarily alter the responses of hemocytes.     

Bioconcentration and Depuration of Chlorpyrifos in the Marine Mollusc Mytilus edulis

The bioconcentration and depuration of chlorpyrifos [O,O-diethyl-O-(3,5,6-trichloro-2-pyridil) phosphorothioate] for the marine mollusc Mytilus edulis was investigated under laboratory conditions in experimental aquaria. Renewal tests at concentrations of 1 and 3.2 mg/L followed by depuration tests were conducted. Organisms were exposed to pesticide concentrations for 38 days and then were maintained in clean sea water until the chlorpyrifos were eliminated. Two different methods to estimate toxicokinetic rate constants of chlorpyrifos were compared. Toxicokinetic rate constants appeared to be dependent upon the level of exposure, probably due to the toxic stress produced by the high exposure level assayed. Lipid based Bioconcentration Factor (BCF) calculated by first order kinetic fit was found to be 482 ± 86. The depuration of chlorpyrifos by mussels maintained in clean sea water was fitted to first order one-compartment model, and the depuration rate constant estimated was similar to that calculated in the bioconcentration phase. The BCF obtained was lower than expected for K _ow of chlorpyrifos, suggesting metabolic biotransformation of the parent pesticide. Received: 18 July 1996/Accepted: 5 January 1997     

Immunomodulation the Marine Green Mussel Perna viridis Exposed to Sub-Lethal Concentrations of Cu and Hg

Environmental pollution is a growing concern and, more importantly, pollution of the aquatic ecosystem is alarming. Marine pollution may be one of the reasons for disease incidence in marine organisms, which is caused due to adverse effects of pollutants on the immune system. Bivalves are commonly used as bio-indicators of marine pollution, and immunomodulation due to toxicants is one of the important bio-markers used. Perna viridis too have been used as a bio-indicator, but this study is, to our knowledge, a first report on immunomodulation produced by metals, in P. viridis. Animals were exposed to copper and mercury at their sub-lethal concentrations of 20 μg L⁻¹ and 10 μg L⁻¹, respectively. Immune parameters including phenoloxidase, reactive oxygen species generation, and phagocytosis were monitored. The study period was for 25 days (chronic long-term exposure) and objectives established whether metals produced immunomodulation and to understand the effects of long-term exposure on immunomodulation. Results showed that both metals adversely affected immune parameters studied and, interestingly, there appears to be some level of recovery (depuration) from the toxic effects of metals.     

贻贝磷脂与大豆磷脂卵黄磷脂组成的比较研究

磷脂是生物膜的重要组成部分 ,具有多种生理活性。近年来研究表明 ,桑寄生、徐长卿、酸枣仁等中药中均含有丰富的磷脂成分 ,何首乌的抗衰老、降血脂、防动脉粥样硬化及保肝作用 ,也是因为含有丰富的肌醇磷脂等磷脂成分[1] 。　　商品磷脂以大豆为主要原料 ,在加工大豆油的副产品中可以回收提纯大量磷脂 ,工艺简单、成本低廉 [2 ] 。大豆磷脂多用于食品或化妆品。鸡蛋常作为药用磷脂的原料 [3 ] ,但鸡蛋本身及提取成本太高。　　贻贝是我国一种重要经济贝类 ,1 999年产量高达 5 4 .1万吨。近几年贻贝多用作饲料或被鲜活销售 ,加工少且品种单…     

Short-term and long-term uptake of zinc by the Mussel,Mytilus edulis: A study in individual variability

In previous studies, the zinc concentration of the whole soft tissue of the musselMytilus edulis showed a high degree of unexplained residual variability which could not be accounted for by any known ecological or physiological factors. This high variability was almost entirely due to the unusually high degree of variability in kidney zinc concentrations (range 97-7,864 g/g; n=561). In the present study, unfed mussels were exposed to natural levels of zinc (labelled with zinc-65) in clean seawater in a laboratory aquarium. In spite of the environmental homogeneity in the laboratory environment, the kidney showed a high coefficient of variation (around 70%) for zinc-65 concentrations after 66 days of exposure to the radioisotope. Other tissues showed only low coefficients of variation (10–30%). This suggested that the high variability of kidney zinc was not a result of unknown ecological factors (differences in microhabitat), but was due to biochemical differences between individual mussels. In a second experiment, it was noted that the zinc-65 and stable zinc concentrations of the kidney showed significant positive correlation after only six days exposure to zinc-65, indicating that the factors leading to the high variability of zinc in the kidney were operative within the first few days after uptake. Hence, kidney zinc variability appeared more likely to be the result of short-term processes (zinc uptake, elimination of zinc from short term compartments) than long-term processes (granule excretion). Female mantle had a higher stable zinc concentration but a lower radio-zinc concentration than male mantles. The radio-zinc concentration of the mantle's edge was greater than that of the mantle without an edge. MSRL Contribution Number 701     

铅锌矿区铅和镉污染对职业人群健康的影响

目的了解铅锌矿区铅镉污染对职业人群健康的影响。方法于2006年3月-2007年3月,选择长期工作和生活在某铅锌矿区的380名职工作为暴露组,以距该矿区40km以外东河上游某镇316名居民作为对照组,进行人群一般状况、内外科常见病检查（包括：自觉症状问诊、阳性体征筛查等）、职业病中毒体征（齿龈铅线、口内金属味、肢端感觉异常等）的检查。结果随着工龄的增加,职业人群发中铅、镉含量也随之增加（P〈0．05,P〈0．01）;暴露组人群头昏、胸闷、口内金属味、腹痛、肢端感觉异常及高血压发生率均高于对照组（P〈0．05,P〈0．01）;暴露组发中铅、镉、锌含量均高于对照组（P〈0．01）。结论铅锌矿区环境污染对职业人群健康有不良影响。     

对氨基水扬酸钠对染锰小鼠免疫功能的影响

为了探讨对氯基水杨酸钠(PAS-Na)治疗锰中毒的作用机理,给小鼠每天ip Mncl_2(0、10、20、40mg/kg)染毒,4周后给予PAS-Na(120mg/kg),连续2周。结果表明;PAS～Na能增加脾NKC活性,增强T细胞功能。PAS-Na可能通过驱出体内的锰或与锰拮抗.恢复部分细胞免疫功能。     

Instrumental and Bioanalytical Measures of Persistent Organochlorines in Blue Mussel (Mytilus edulis) from Korean Coastal Waters

Blue mussels (Mytilus edulis) collected from 34 locations along the south and east coast of Korea were analyzed for polychlorinated biphenyls (PCBs) and organochlorine (OC) pesticides. Maximum concentrations of PCBs and total OC pesticides were 98.5 and 20.5 ng/g, wet weight, respectively. Extracts were fractionated by Florisil chromatography and each fraction was screened for dioxin-like activity in vitro, using recombinant rat hepatoma cells (H4IIE-luc). Fraction 2 (F-2), which contained hexachlorocyclohexanes, chlordanes, p,p′-DDD, and p,p′-DDT, generally elicited significant dioxin-like activity compared to control, whereas Fraction 1 (F-1), which contained PCBs, p,p′-DDE, and hexachlorobenzene, did not. The greatest magnitude of dioxin-like response observed was 44% of the maximum response elicited by a 2,000 pM 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) standard. The relatively low magnitudes of dioxin-like response observed for F-1 samples were consistent with the relatively low PCB concentrations. At concentrations equal to the maximum observed in the mussel samples, neither individual OC pesticides nor a mixture of OC pesticides yielded a significant dioxin-like response in the H4IIE-luc assay. Thus, the concentrations of OC pesticides in F-2 did not appear to have accounted for the dioxin-like activity observed. This suggests the presence of unidentified and/or unknown, acid-stable, dioxin-like compounds in F-2. This study suggests that in vitro bioassays are useful in assessing the contamination of mussels collected from coastal marine locations. Received: 28 November 1999/Accepted: 3 May 2000     

环境镉污染及其对人群健康影响的研究

比较某冶炼厂15年前后环境镉污染对人群健康影响的变化,并为该厂扩建投产后的污染变化评价提供依据。方法：选取与上次调查相同的污染区和对照区,调查两区大米,蔬菜,饮水镉以及25岁以上妇女的尿中镉,β2－M,NAG酶含量,并与上次资料比较,结果：米镉（干重）,菜镉（湿重）,饮水镉,尿镉,尿β2－M和尿NAG酶的几何均数,污染区分别为1．75mg/kg,0.27mg/kg,0.0008mg/L,13.34ug/g.cr,185.39ug/g.cr和5．80U/g.cr,对照区分别为0．46mg/kg.0.08mg/kg.0.001mg/L,2.27ug/g.cr.136.57ug/g.cr和4.06U/g.cr;其中米,菜,尿3项镉浓度,污染区比对照区高（P＜0．01）,尿镉,尿NAG酶,尿β2－M及其总的异常率,污染区（37．63％,19．35％,18．28％和51．6％）高于对照区（7．23％,3．61％,7．23％和15．7％）（P＝0．000－0．013）;本次调查污染区的尿镉均值（23．80ug/L)和异常率（44．09％）约为1982年的（12．06ug/L和22．52％）2倍（P＜0．01或P＝0．022）,并检出3例（3．2％）慢性早期健康危害。结论：研究认为该污染区以及污染区人群仍在继续遭受某冶炼厂环境镉污染的影响,而且这种影响有不断累积加重的趋势。但该污染区镉尚未地当地人群构成慢性早期健康危害。关键词：镉,环境污染;健康效应;尿β2－微球蛋白;尿N－乙酰－β－D－氨基葡萄糖苷酶。     

氧化镉对作业工人尿镉、尿β2微球蛋白水平的影响

目的探讨空气中氧化镉粉尘对作业工人尿镉、尿β2-微球蛋白水平的影响.方法对某电池厂氧化镉作业工人493人及对照组283人进行尿镉、尿β2-微球蛋白测定分析,结果氧化镉接触组尿镉含量高于对照组(P＜0.01),且随着接触工龄的延长而逐渐升高.接触组尿β2-微球蛋白含量略高于对照组,但差异无统计学意义,当工龄≥3年时差异才有统计学意义(P＜0.05).结论氧化镉的暴露与尿镉呈正相关关系,尿β2-微球蛋白是肾损害的早期指标.     

牛磺酸对镉染毒小鼠的保护作用

[目的]初步探讨牛磺酸对镉所诱导的遗传毒性的拮抗作用。[方法]①小鼠骨髓嗜多染红细胞微核检测：受试动物按单纯氯化镉剂量分为：O．70mg、1．35mg、2．70mg三级及相应的加牛磺酸(1000mg／l(g)三组，另设阴性对照组和环磷酰胺组，共八组，分别计算其微核率。②小鼠精子畸形检测：按单纯氯化镉剂量为：0．50、1．00mg／kg二级及相应的加牛磺酸(1000mg／kg)二组，另设阴性对照组和环磷酰胺组，共六组，计算其精子畸形率。③受试动物分单纯氯化镉组(1．35mg／kg)、牛磺酸组(1000mg／kg)及相应的牛磺酸加氯化镉组，再设阴性对照组，共四组，用原子吸收分光光度法测其肝脏、睾丸中的镉(Cd)、铜(Cu)、锌(Zn)元素含量的变化。[结果]氯化镉各组脏器中CA含量均高于阴性对照组；牛磺酸加氮化镉各组肝脏Cd、Cu、Zn含量均为明显高于氯化镉各组，睾丸中Cd含量(0．539μg／g)则明显低于氯化镉各组(O．683μg／g。氯化镉各组小鼠骨髓嗜多染红细胞微核率分别为6．75‰、10．88‰、11.13‰和精子畸形率分别为40．88‰、59．00‰，明显高于阴性对照组(微核率1．88‰、精子畸形率33．38‰)，牛磺酸加氯化镉各组，微核率分别为4．75‰、5．13‰、5．63‰和精子畸形率分别为27，13‰、30．57‰，明显低于相应的氯化镉组。[结论]牛磺酸使急性镉中毒小鼠体内元素分布发生一定变化，且对镉的遗传毒性有一定的拮抗作用。     

镉致作业工人肾功能损害可逆性研究初探

[目的 ]观察接受依地酸二钠 (EDTA)治疗慢性镉接触工人尿镉和肾功能改变 ,以探讨镉接触致肾损害的可逆性。 [方法 ]收集 1986年以来某冶炼厂接受EDTA治疗的 17名镉接触工人 (其中男 14名 ,女 3名 )每年治疗前后尿镉和尿 β2 微球蛋白 (β2 MG)的记录 ,分析其变化的情况。 [结果 ]尿 β2 MG一直异常 (≥ 0 8mg/g·Cr)或由正常转为异常的工人 ,尿镉平均水平基本高于 10 μg/g·Cr ,治疗期间尿 β2 MG一直正常或出现异常又转为正常的工人 ,尿镉平均水平在 10μg/g·Cr以下 ;整个治疗过程中 ,不论尿镉升高或降低 ,尿 β2 MG异常率均有所上升 ;随着镉接触终止时间的延长 ,尿 β2 MG没有下降 ;尿镉水平低于 10 μg/gCr ,肾损害可以恢复 ,反之 ,则不可逆。[结论 ]尿镉的水平是影响镉接触工人肾功能变化的主要因素 ,EDTA对镉接触工人肾功能损害没有明显疗效。     

Role of cAMP in Tissues of Mussel <Emphasis Type="Italic">Mytilus galloprovincialis</Emphasis> As a Potent Biomarker of Cadmium in Marine Environments

Pesticides with chlorpyrifos and endosulfan as active element are used for pest control on agricultural lands and are high-risk inputs in aquatic systems. The acute toxicity of these insecticides in the freshwater prawn Palaemonetes argentinus was evaluated. The results were used to determine the lowest observed–effect and no observed–effect concentrations. Individual growth of prawns in relation to chlorpyrifos and endosulfan exposure was analyzed. LC₅₀ values to chlorpyrifos and endosulfan exposure were 2.98 μg L^–1 and 14.10 at 24 hours and 0.49 μg L^–1 and 6.28 μg L^–1 at 96 hours of exposure, respectively. The size increment of prawns was the same in all treatments; cephalothorax length increased linearly per molt. The intermolt period was influenced by the toxic effect of pesticides during rearing time, and this decreased with the molt cycles compared with the normal growth pattern. The results suggest that juveniles of P. argentinus are sensitive to chlorpyrifos and endosulfan pollution.