广东省常见河豚鱼含毒状况研究

为了解河豚鱼的带毒状况，于1996年4-12月采集了广东省沿海捕捞的4个常见品种天然河豚鱼共64尾，用ELISA检测法对河豚鱼不同组织部位进行河豚毒素(TIX)含量检测。结果显示4种河豚鱼肝脏带毒率为0-21．5％，肝脏毒力平均值范围是0．05～9．92Mu／g，其中横纹东方豚肝脏毒力最大值为106．6Mu／g，属于强毒；4种河豚鱼性腺带毒率为0-16．67％，性腺毒力平均值范围是0．2～34．1Mu／g，其中横纹东方豚性腺最大毒力属于强毒；鱼皮和肌肉的平均毒力均属无毒。本次研究初步确定黄鳍东方豚、棕斑腹刺豚和暗鳍腹刺豚3种天然河豚鱼属肌肉无毒品种，可以安全食用。     

浙江省沿海河豚鱼生态分布和毒素检测

目的 了解我省沿海河豚鱼毒性分布情况。为控制和降低中毒事件发生，合理开发河豚鱼资源。方法 采用生物学鉴定方法分别测量体长、体重、性腺识别和称重、观察鱼体的斑纹(斑点)等鉴定鱼种。采用直接竞争抑制ELISA法，测定河豚鱼肌肉、性腺、肝、皮的带毒情况。结果 采集的河豚鱼种类共有9种，以黄鳍东方豚为主，占63．02％；季节分布以4、5、6月获得的标本为多，占总数的54．62％。带毒检测中，8份TTX含量较高的标本分别为菊黄东方豚的肝、皮部位，分别达445鼠单位，按东方河豚毒素毒力单位判定，可判为“强毒”等级；黄鳍东方豚其TTX含量较低。结论 菊黄东方豚是我省常见的河豚鱼种类之一，毒素检测显示其皮及肝脏为强毒，应加强对这一鱼种的识别和控制食用。     

六种河豚鱼组织中EPA与DHA含量调查

目的：分析河豚鱼组织中EPA(二十碳五烯酸)、DHA(二十二碳六烯酸)含量及其利用价值。方法：利用带FID检测器的气相色谱仪作为检测设备，取河豚鱼的肌肉、肝脏进行EPA、DHA定量测定。结果：河豚鱼肌肉未能检出EPA、DHA；肝脏含EPA范围0．0367．800g／kg，含DHA范围0．030-45．672g／kg；东方豚肝脏中EPA、DHA含量显著高于腹刺豚；无毒的棕腹刺豚和暗鳍腹刺豚肝脏内的EPA、DHA含量差异有统计学意义。结论：河豚鱼肝脏含有丰富的EPA、DHA。棕腹刺豚肝脏没有毒性，是摄取EPA、DHA的可利用资源。     

大鹏湾海域河豚鱼毒性状况研究

目的　掌握深圳大鹏湾海域河豚鱼毒性状况。方法　采集渔民在大鹏湾海域捕获的河豚鱼鲜活或冰鲜 ,采用小鼠生物试验法测定样本鱼不同组织的河豚鱼毒素 (TTX)含量。结果　共检测了五种河豚鱼样本 ,92份棕腹刺豚和 5份暗鳍腹刺豚样本鱼均未检出毒性 ;1份园斑腹刺豚、9份星点东方豚和 2 6份弓斑东方豚样本鱼各组织均检出毒性 ,肝脏毒力均值范围为 1 83 0 0～ 5 1 1 75MU/g,卵巢毒力均值范围为 2 1 2 84～ 35 4 1 0MU/g ,皮肤毒力均值范围为 9 2 1～ 38 31MU/g ,精巢毒力均值范围为 1 1 4 0～ 2 5 6 4MU/g,肌肉毒力均值范围为 7 2 3～ 9 1 7MU/g。弓斑东方豚卵巢的毒力在 3～ 4月份明显高于 9～ 1 0月份并高于其他组织。结论　本次检测的大鹏湾产的园斑腹刺豚、星点东方豚和弓斑东方豚均为有毒鱼种 ,可认为棕腹刺豚是一种可以安全利用的无毒河豚鱼种     

河豚鱼试食试验的关键控制点探讨

河豚鱼味道鲜美、营养丰富,但其毒性很强。河豚鱼毒性与河豚鱼品种、产地(海域)、捕捞季节及食用部位等因素密切相关。针对上述危害因素我们在试食试验中,检测河豚鱼毒力并分析明确关键控制点,制定控制措施。结果报告如下。材料与方法(1)品种:确定本省海域,非产卵期的红鳍东方豚为试食试验品种,限定食用部位为肌肉和真皮。(2)方法:采用通用的河豚鱼毒力测判定方法即<10个鼠单位/g为无毒级。结果(1)红鳍东方豚毒力检测:共检测48尾红鳍东方豚,其真皮毒力最高值为7·9鼠单位/g,最低值为0·1鼠单位/g,平均2·8鼠单位/g;肌肉毒力最高值为5·9鼠单…     

黄鳍东方豚体内毒素分布探讨

河豚鱼味道鲜美,但由于人们对河豚鱼体内毒素分布的了解甚少,吃河豚鱼引起食物中毒,甚至死亡常有发生。为了全面了解河豚鱼体内的毒素分布情况,本文对我县沿海捕捞上来的黄鳍东方豚作了毒素分布检测分析。1 实验过程1.1 样品来源 渔船捕捞上来的新鲜黄鳍东方豚要求250 g以上,冷藏,每月采集一次。由于7～8月是禁渔期,故无样品,共计采集样品51尾。每尾鱼用流水清洗干净,取皮、肌肉、肝脏、肾脏和性腺各5 g,分别捣碎。1.2 毒素提取与检测 按1996年《浙江省河豚鱼生态学及毒力监测》课题中的方法操作,样品毒素提取液,送卫生部食监所,统一做TTX(河豚鱼毒素)检测。2 结果     

东海加工用河鲀鱼种毒性研究

应用酶联免疫方法，对分布于中国东海，应用地加工河豚鱼干制品的五种主要河鱼种毒性进行了调查研究。毒素含量范围为＜４．０×１０－２＞１．０×１０４ＭＵ／ｇ。即使处于繁殖期，暗鳍、淡鳍腹刺仍均属无毒或弱毒级。头纹宽吻和横纹东方则具有相当大的毒性。毒素含量随其生活的环境、海域及季节变化。建议在监督控制下，批准部分具备条件的企业进行河鱼干制品的加工生产，但应明确限制允许加工的腹刺属鱼种     

棕腹刺豚的食用安全性及营养成分分析

目的 开展对棕腹刺豚的含毒状况食用安全性调查和营养分析，为棕腹刺豚的利用提供科学依据。方法 采用小鼠生物试验法测定各组织毒性；调查居民对河豚的知识、态度和行为状况；参照食品检验国标方法测定棕腹刺豚的营养成分。结果 棕腹刺豚各组织均未检出毒性；沿海原居民认为棕腹刺豚皮肤、肌肉、肝脏无毒性并有长期食用史；肌肉含蛋白质19．3％，必需氨基酸占氨基酸总量44．52％，肝脏含二十碳五烯酸(EPA)0．674g／kg、二十二碳六烯酸(DHA)5．881g／kg，肝组织锌含量103．5mg／kg。结论 深圳大鹏湾海域的棕腹刺豚无毒性，含丰富的蛋白质、人体必需脂肪酸和锌元素，是一种可以安全食用的河豚鱼种。     

8.0%杀鼠灵母液对大白鼠急慢性毒力实验

目的：测定8．0％杀鼠灵母液对大白鼠的急慢性毒力。方法：且次或连续5次经口灌胃。结果：1次经口灌胃LDS50为1414mg／kg，属低毒；连续5次经口灌胃LD50为6．60mg／km，属高毒。结论：其急与慢性毒力差异大，使用安全，毒效可靠。     

两种方法检测织纹螺中麻痹性毒素的分析比较

目的：了解织纹螺带毒情况，探讨织纹螺毒素特征。方法：用小鼠生物法测定织纹螺麻痹性毒素；用ELISA法测定STX，按织纹螺肉中毒素含量≥400MU／100g或STX≥80μg／100g判为对人有毒害的毒螺。结果：小鼠生物法测定检出有毒织纹螺51份，占总数的32．90％。以中毒样品检出毒螺的数量最多，占总数的23．23％，检出的毒素含量最高达21600 MU／100g肉，其毒性也是最强的；其次为监测点样品，毒螺的检出数量为9．03％，市场样品较少，而新产螺点样品未检出有毒织纹螺。ELISA法测定检出毒螺16份，带毒率为10．32％，两法同时检出毒螺的仅为29．57％，在毒素含量和检出毒螺的数量上ELISA法明显低于小鼠生物法，两者存在显著性差异P〈0．05。结论：宁波市织纹螺的毒性较强，小鼠生物法检出的毒性反映了织纹螺携带的实际毒力，ELISA法检出的是织纹螺中STX含量，说明织纹螺中携带的毒素不仅仅是PSP，该结论与以往报道的织纹螺携带的毒素主要是PSP不一致，提示我们为进一步控制织纹螺中毒，有深入探讨织纹螺麻痹类毒素必要。     

绿茶对微囊藻毒素诱导肝肾氧化损伤的拮抗效应

目的探究绿茶对微囊藻毒素LR（MC-LR）诱导肝肾氧化损伤的拮抗效应。方法40只雄性小鼠分为空白对照组、MC-LR染毒组（MC-LR）、绿茶低剂量拮抗组（MC-LR＋绿茶2）、绿茶高剂量拮抗组（MC-LR＋绿茶12）共4组,实验第1天起MC-LR＋绿茶2、MC-LR＋绿茶12组即每日给予2g／L和12∥L的绿茶自由饮用,连续18d。自第6天开始,MC-LR、MC-LR＋绿茶2、MC-LR＋绿茶12组均每日给予MC-LR10μg／kg腹腔注射1次,空白对照组给予二甲砜腹腔注射,连续13d。第19天眶静脉取血后处死动物,对脏器系数、血清生化指标、抗氧化酶及脂质过氧化物水平、肝肾组织病理改变等指标进行检测和分析。结果绿茶明显拮抗MC-LR所致小鼠体重的下降。绿茶明显拮抗MC-LR造成的血清丙氨酸转氨酶、天冬氨酸转氨酶和肌酐的升高。绿茶可抑制MC-LR致小鼠脂质过氧化物丙二醛水平的升高,较MC-LR染毒组MDA均值13．98nmol／ml相比差异有统计学意义。绿茶高剂量拮抗明显升高血清谷胱甘肽及超氧化物歧化酶水平,其均值分别为467．29mg／L和139．22U／ml,与空白、MC-LR染毒组相比差异有统计学意义。给予绿茶可使MC．LR所致的肝肾病理损伤减轻。结论绿茶可提高抗氧化酶活性,清除体内自由基,减轻氧化损伤,从而明显拮抗MC-LR诱导的肝肾毒性损伤。     

Differences in tissue fatty acid composition between reared and wild sharpsnout sea bream, Diplodus puntazzo (Cetti, 1777).

The fatty acid composition and lipid content of white muscle, liver and mesenteric fat, in reared v. wild sharpsnout sea bream (Diplodus puntazzo) were compared. The mesenteric fat index fat weight/body weight) and the lipid contents of both white muscle and liver proved consistently higher in farmed v. wild sharpsnout sea bream (79.0 (SE 13.1) v. 38.7 (SE 5.1) g/kg, 188.4 (SE 30.0) v. 58.2 (SE 3.9) g/kg and 27.2 (SE 3.7) v. 17.3 (SE 1.9) g/kg, respectively). The higher values of linoleic, eicosapentaenoic, docosahexaenoic and n-3 series acids in reared fish muscle make reared sharpsnout more favourable for human consumption. In reared fish mesenteric fat, polyunsaturated fatty acids reached higher levels (32.54 (SE 0.71) g/100 g total fatty acids than those found in wild fish (26.08 (SE 1.38) g/100 g total fatty acids or even present in the diet (28.34 g/100 g total fatty acids). Compared with cultured fish, wild sharpsnout displayed a higher content of n-3 fatty acids in liver fat (31.67 (SE 1.13) g/100 g total fatty acids), but lower in mesenteric fat (20.35 (SE 1.41) g/100 g total fatty acids). Atherogenic index values were similar for wild and reared fish in all tissues, while the index of thrombogenicity of muscle and mesenteric fat (0.353 (SE 0.012) and 0.402 (SE 0.021) respectively) was significantly increased in wild fish probably due to the omnivorous habits of the species and/or to seasonal food variations. Depending on the time of the year or the season, reared fish could be more suitable for human consumption than wild fish.     

壬基酚对红鲫、草鱼和鲢鱼的毒性及组织蓄积研究

目的了解不同鱼种对壬基酚的毒性差异。方法选择红鲫、草鱼和鲢鱼鱼苗,4-壬基酚换水式染毒进行96h急性毒性试验、12周亚慢性毒性试验、外周血红细胞微核试验,高效液相色谱法测定组织中4-壬基酚。结果①4-壬基酚对红鲫、草鱼和鲢鱼的96h LC50分别为251.30、155.84和187.01μg/L。②染毒12周,红鲫高剂量组肝胰脏系数降低,中、高剂量组卵巢系数增高(P<0.05);草鱼中剂量组肾脏系数降低(P<0.05);鲢鱼高剂量组肝胰脏系数降低(P<0.05)。③染毒4周时,红鲫和鲢鱼中、高剂量组及草鱼高剂量组微核细胞率与对照组相比显著增高(P<0.05);染毒8周及以后,受试鱼各剂量组微核细胞率均增高(P<0.05);④受试鱼肌肉、脑和肝胰脏等组织样品中均有4-壬基酚检出,其中肝胰脏的生物浓缩系数最高;红鲫对4-壬基酚的生物浓缩系数高于草鱼和鲢鱼。结论红鲫对壬基酚较敏感。     

Long-term exposure of European flounder (Platichthys flesus) to the flame-retardants tetrabromobisphenol A (TBBPA) and hexabromocyclododecane (HBCD)

Tetrabromobisphenol A (TBBPA) and hexabromocyclododecane (HBCD) are widely used flame retardants that have increasingly been found as contaminants in the aquatic environment. In the present study, European flounder (Platichthys flesus) were chronically exposed to TBBPA; (105 days) and HBCD (78 days), in a wide range including environmentally relevant concentrations. TBBPA was administered via the water, whereas HBCD was administered in food and sediment, or in sediment alone. Chemical analysis of muscle showed an average increase in internal concentrations of approximately two orders of magnitude for both compounds tested. Animals exposed to HBCD via sediment alone (8000 microg/g total organic carbon, TOC) showed a proportional increase of alpha-HBCD in muscle compared to animals exposed via food and sediment. In both studies, exposure to the test compounds did not affect general health and toxicity parameters (behavior, survival, growth rate, relative liver and gonad weight). Hepatic microsomal enzyme activities (TBBPA: EROD; HBCD: EROD, PROD, and BROD) were not induced by any of the tested chemicals. Aromatase activity in male gonads showed a mild increase with rising TBBPA levels. There were no morphological and immunohistochemical indications for increased production of the yolk precursor protein vitellogenin (VTG) in animals exposed to TBBPA and HBCD; immunochemical analysis of plasma VTG levels showed no dose response in animals exposed to TBBPA. In animals exposed to TBBPA, levels of the thyroid hormone thyroxin (T(4)) increased with internal concentrations of the test compound, possibly indicating competition of TBBPA for plasma protein binding. Triiodothyronin (T(3)) levels were not affected and histology showed no signs of altered thyroid gland activity. Other organs investigated (liver, gills, kidney, skin, and gonads) revealed no histological changes related to TBBPA or HBCD exposure. Overall, the present results indicate limited endocrine effects of these widely used flame retardants in a test species representative of European estuaries at environmentally relevant exposure levels and at internal levels up to 4300 ng TBBPA/g wet weight, and 446 microg HBCD/g lipid weight in flounder muscle.     

Toxicity and accumulation of cadmium in the crayfish,Orconectes virilis (Hagen)

The acute toxicity of cadmium to the crayfishOrconectes virilis was determined over a two week exposure period. Crayfish exhibited an increased sensitivity to cadmium over time; LC50 values decreased from 6.1 mg Cd/L for 96 hr to 0.70 mg Cd/L for 14 days. An incipient LC50 value of 0.06 mg Cd/L was also calculated forO. virilis. Whole animal and tissue analyses for cadmium were performed on the crayfish used in the acute toxicity experiments. Whole animal cadmium concentrations exhibited a linear relationship to exposure concentrations as did the gill and antennal glands. Cadmium tissue concentrations were from highest to lowest in the following tissues: gill > hepatopancreas > antennal gland > carapace and abdominal muscle.     

Microcystin kinetics (bioaccumulation and elimination) and biochemical responses in common carp (Cyprinus carpio) and silver carp (Hypophthalmichthys molitrix) exposed to toxic cyanobacterial blooms

Two species of common edible fish, common carp (Cyprinus carpio) and silver carp (Hypophthalmichthys molitrix), were exposed to a Microcystis spp.-dominated natural cyanobacterial water bloom for two months (concentrations of cyanobacterial toxin microcystin, 182-539 microg/g biomass dry wt). Toxins accumulated up to 1.4 to 29 ng/g fresh weight and 3.3 to 19 ng/g in the muscle of silver carp and common carp, respectively, as determined by enzyme-linked immunosorbent immunoassay. Concentrations an order of magnitude higher were detected in hepatopancreas (up to 226 ng/g in silver carp), with a peak after the initial four weeks. Calculated bioconcentration factors ranged from 0.6 to 1.7 for muscle and from 7.3 to 13.3 for hepatopancreas. Microcystins were completely eliminated within one to two weeks from both muscle and hepatopancreas after the transfer of fish with accumulated toxins to clean water. Mean estimated elimination half-lives ranged from 0.7 d in silver carp muscle to 8.4 d in common carp liver. The present study also showed significant modulations of several biochemical markers in hepatopancreas of fish exposed to cyanobacteria. Levels of glutathione and catalytic activities of glutathione S-transferase and glutathione reductase were induced in both species, indicating oxidative stress and enhanced detoxification processes. Calculation of hazard indexes using conservative U.S. Environmental Protection Agency methodology indicated rather low risks of microcystins accumulated in edible fish, but several uncertainties should be explored.     

Assessment of the freshwater annual fish Cynopoecilus melanotaenia as a toxicity test organism using three reference substances

This study presents a preliminary evaluation of the use of the Brazilian fish Cynopoecilus melanotaenia as a test organism in toxicity tests. The cryptobiotic stage presented by the eggs of fish C. melanotaenia can overcome the difficulty of continuously keeping cultures and recruiting healthy animals in sufficient numbers to be used in toxicity tests. In order to determine the applicability of this species as a test organism, three different reference substances were evaluated in 96-h acute toxicity tests: Copper sulfate (CuSO4 x 5H2O), sodium dodecil sulfate (C12H25NaO4S), and sodium chloride (NaCl). Sensitivity ranged as follows: copper sulfate (0.05-0.13 mg/L), sodium dodecil sulfate (10.7-19.0 mg/L), and sodium chloride (1.44-1.96 g/L). We conclude that C. melanotaenia shows potential as a test organism in toxicity tests; however, further research should be conducted with other substances and should be compared with the research on other species before we can reach more conclusive results.     

Selenium impacts on razorback sucker, Colorado River, Colorado I. Adults

Adult razorback sucker (Xyrauchen texanus) were exposed to various selenium concentrations in ponds and isolated river channels of the Colorado River near Grand Junction, CO, to determine effects on their growth and residue accumulation over an 11-month period. Adults at Horsethief ponds were fed a commercial diet, whereas fish at Adobe Creek channel and North Pond foraged on natural food items. Selenium concentrations at Horsethief were 2.2 microg/L in water, 0.1-1.4 microg/g in sediment, and 2.3-3.1 microg/g in food organisms (1.1 microg/g in commercial fish food), at Adobe Creek were 3.8 microg/L in water, 0.5-2.1 microg/g in sediment, and 4-56 microg/g in food organisms, and at North Pond were 9.5 microg/L in water, 7-55 microg/g in sediment, and 20-81 microg/g in food organisms. The selenium concentrations in muscle plugs from adults at Adobe Creek (11.7 microg/g, SD = 0.4, n = 6) and North Pond (16.6 microg/g, SD = 1.0, n = 6) were greater than at Horsethief (4.5 microg/g, SD = 0.2, n = 6). During a depuration period adults from Adobe Creek and North Pond lost 1-2% of their selenium burden in 32 days and 14-19% in 66 days. Selenium accumulated in razorback sucker above toxic thresholds reported in other studies, yet those residues were less than those reported in muscle plugs of 40% of wild razorback sucker caught in the Green River, Utah.     

砷暴露小鼠肝组织核酸损伤免疫组织化学观察

目的为进一步研究砷对肝脏的毒性作用机制提供实验依据。方法昆明种小鼠40只,随机分为4组：1,2,4 mg/L三氧化二砷染毒组和生理盐水组,连续染毒60 d,取小鼠肝组织固定,用免疫组化方法观察肝脏组织细胞的8-Nitroguanine表达。结果染砷组小鼠肝细胞出现抗8-Nitroguanine免疫染色阳性反应,并随着砷暴露剂量的增加而呈现明显的剂量-反应关系。结论慢性低剂量砷暴露可诱发小鼠肝细胞8-Nitroguanine的高表达,提示8-硝基鸟嘌呤核苷（8-Nitroguanine）可以作为砷对肝细胞毒性作用的早期敏感生物标志物。     

吡哆素L-2-吡咯烷酮-5-羧酸酯生殖毒性机制研究

目的研究吡哆素L-2-吡咯烷酮-5-羧酸酯（MTDX）及其组成物之一VitB6对原代培养睾丸支持细胞分泌乳酸和体外对睾丸合成睾酮的影响,探讨MTDX可能生殖毒性作用机制。方法胰蛋白酶和Ⅳ胶原酶两步分离法分离雄性SD大鼠睾丸支持细胞进行体外培养,分别加入不同浓度的MTDX（0.17 g/L,1.7 g/L,17.0 g/L和34.0 g/L）、不同浓度VitB6（0.1 g/L,1.0 g/L,10.0 g/L和20.0 g/L）,24 h后收集培养液测定乳酸含量。利用离体组织培养和放射免疫技术,观察不同浓度的MTDX是否对大鼠睾丸睾酮的分泌有直接作用。结果与对照组相比,MTDX 17.0 g/L和34.0 g/L剂量组乳酸含量减少;与对照组相比,VitB610.0 g/L和20.0 g/L剂量组乳酸含量减少。MTDX各剂量组和VitB6各剂量组睾丸培养液中睾酮的含量与对照组相比差异均无统计学意义。结论MTDX可能通过减少了睾丸支持细胞乳酸的分泌而影响生殖细胞的功能,进而影响正常生殖;MTDX对睾丸分泌睾酮没有直接的抑制作用,可能对睾丸间质细胞正常功能没有影响;MTDX的生殖损害可能由其聚合物（组成物）之一VitB引起。