BIOACCUMULATION IN SELECTED TISSUES OF LABORATORY EXPOSED CRAYFISH

文献中有压倒性的证据表明，重金属在 一般和汞，特别是铬和铜构成了一个很大的 对环境，包括对人类的危害。对人类健康的关注 这些金属怎么强调都不为过。长期暴露在水中 而食物链最终会导致致癌物质的生物积累 (铬)和剧毒金属(汞和铜)在组织中 并被传染给作为主要消费者的人类。两个人 这项研究的主要目的是：(1)调查 这些金属在小龙虾组织中的生物累积潜力(实验室。 暴露的)和在现场收集的那些，以及(2)评估急性 以及这些金属对小龙虾种群的慢性毒性。第一 目标将通过将成年小龙虾亚致死地暴露于 每种金属化合物12周，并分析它们的组织 用原子吸收光谱法测定它们的摄取。相同数量的小龙虾(前 连续接触每种金属12周)将被转移到 未受污染的水和这些金属的净化程度将被测量 在接下来的12周里也是如此。从水族箱抽取的水样 净化小龙虾也将通过原子吸收光谱进行分析，以确定数量 释放到未受污染的水中的金属。这将为我们提供 准确地说是摄取和净化阶段的数据。贝斯的小龙虾 将对路易斯安那州的主要高速公路进行分析，以确定 这些毒物的全身负担。对青少年的急性毒性 小龙虾将通过96小时的静态生物检测和 建立LC_(50)值。成人将确定LC_0和LC_99 小龙虾，使用计算机化的概率分析程序，这也给出了 上半身和情人的致死浓度。慢性毒性将是 确定依据：(1)亚致死性暴露新生小龙虾(0.8-LCM 长度)，并测量与之相比的增长率 对照，(2)测量预先接触过的雌性的生殖力 交配前的亚致死浓度，直到产卵，(3) 评估处理和未处理的孵化率，(4)观察 在生长期暴露期间可察觉到的行为变化。 此外，每种金属可能的致畸作用将是 通过对蛋、胚胎和新孵化的 路易斯安那州的小龙虾。克氏原甲鱼Procambarus clarkii Girard.

There is an overwhelming evidence in the literature that heavy metals in general and mercury, chromium and copper in particular pose a great hazard to the environment, including man. The human health concern for these metals can hardly be overemphasized. Long term exposure to water and food-chain can ultimately result in bioaccumulation of carcinogenic (chromium) and extremely toxic (mercury and copper) metals in the tissues of crayfish and be passed on to humans who are primary consumers. The two major objectives of this study are: (1) to investigate the bioaccumulative potential of these metals in crayfish tissues (lab. exposed) and those collected in the field, and (2) to assess the acute and chronic toxicities of these metals to crayfish populations. The first objective will be achieved by sublethally exposing the adult crayfish to each metal compound for a period of 12 weeks and analyzing their tissues by AAS to determine their uptake. The same number of crayfish (pre- exposed to each metal for 12 wks) continuously will be transferred to uncontaminated water and the depuration of these metals will be measured similarly for the next 12 wks. Water samples from containers of the depurating crayfish will also be analyzed by AAS to determine the amount of metals released into the uncontaminated water. This will provide us precisely the data for uptake and depuration phases. Crayfish from bayous alongside major highways of Louisiana will be analyzed to determine the whole-body burden of these toxicant. Acute toxicities to juvenile crayfish will be determined through 96-h static bioassays and the establishment of LC50 values. LC0 and LC99 will be determined for adult crayfish, using a computerized probit analysis program, which also gives the upper and lover lethal concentrations. Chronic toxicities will be determined by: (1) sublethally exposing newly-born crayfish (0.8-lcm length) for 16 wks and measuring the growth-rate in comparison to controls, (2) measuring the fecundity of females pre-exposed to sub-lethal concentrations before mating till the eggs are laid, (3) assessing the hatchability of treated vs. untreated, (4) observing any discernible behavioral change during the exposure of growth-period. Additionally the possible teratogenic affects of each metal will be determined by microscopic examination of eggs, embryos and newly hatched Louisiana crayfish. Procambarus clarkii Girard.