BIOACCUMULATION IN SELECTED TISSUES OF LABORATORY EXPOSED CRAYFISH

文献中有大量证据表明，重金属 一般而言，汞、铬和铜尤其构成了很大的 对环境（包括人类）造成危害。对人类健康的关注 这些金属的重要性怎么强调都不为过。长期接触水 食物链最终会导致致癌物质的生物累积 组织中的（铬）和剧毒（汞和铜）金属 的小龙虾并传播给作为主要消费者的人类。两人 本研究的主要目的是：（1）研究 这些金属在小龙虾组织中的生物累积潜力（实验室。 暴露）和在现场收集的数据，以及（2）评估急性 这些金属对小龙虾种群的慢性毒性。第一个 通过将成年小龙虾亚致死地暴露于环境中来实现目标 每种金属化合物为期 12 周并分析其组织 通过 AAS 来确定它们的吸收。相同数量的小龙虾（预 连续暴露于每种金属 12 周）将被转移到 将测量未受污染的水和这些金属的净化情况 接下来的 12 周也是如此。容器中的水样 净化后的小龙虾也将通过 AAS 进行分析以确定其数量 释放到未受污染水中的金属。这将为我们提供 精确地获取和净化阶段的数据。来自海湾的小龙虾 将分析路易斯安那州主要高速公路沿线的 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 小时静态生物测定进行测定， 建立LC50值。 LC0和LC99将针对成人确定 小龙虾，使用计算机化的概率分析程序，该程序还给出 上限和情人致死浓度。会产生慢性毒性 测定方法： (1) 亚致死暴露新生小龙虾 (0.8-lcm 长度）16周并测量与 对照，（2）测量预先暴露于的雌性的生育力 交配前至产卵前的亚致死浓度，(3) 评估处理与未处理的孵化率，(4) 观察任何 在生长期间暴露的明显行为变化。 此外，每种金属可能具有致畸作用 通过对卵、胚胎和新孵出的卵进行显微镜检查来确定 路易斯安那小龙虾。克氏原螯虾。

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.