García-Luque Enrique, DelValls Angel T, Forja Jesus M, Gómez-Parra Abelardo
Departamento de Química Física, Universidad de Cádiz, Facultad de Ciencias del Mar (CASEM), Campus Río San Pedro s/n, 11510, Puerto Real, Cádiz, Spain.
Environ Monit Assess. 2007 Aug;131(1-3):27-35. doi: 10.1007/s10661-006-9444-x. Epub 2006 Oct 28.
Toxic effects of pollutants on marine organisms can be studied both by performing field measurements, and by undertaking laboratory simulation experiments. Here is described the effect of trace metals Zn, Cd, Pb and Cu on the clam Scrobicularia plana along a salinity gradient simulated in a hypothetical estuary using simulation experiments. The simulator produces a continuous entry of trace metals into the estuary through injection in the lower salinity tank of the system. The clams were exposed during two weeks to different concentration of trace metals to assess the bioaccumulation process along a salinity gradient. Bivalves were analysed for body tissue residue to determine the bioaccumulation factors related to each metal and the salinity influence was addressed. Differences among tanks were observed as a result of the salinity gradient. In the achieved assays, the mechanism of bioaccumulation of Zn and Cd in organisms was more efficient at high salinity values. Bioaccumulation factors for both metals showed a linear increase with the increase of salinity values. It seems that the mechanism of bioaccumulation of Pb and Cu in organisms was dependent on two simultaneous processes: the proximity to the input point of metals and the low salinity values.
污染物对海洋生物的毒性作用既可以通过进行实地测量来研究，也可以通过开展实验室模拟实验来研究。本文描述了在一个假设的河口利用模拟实验，沿着盐度梯度研究痕量金属锌、镉、铅和铜对扁平蚬的影响。该模拟器通过向系统的低盐度水箱中注入金属，使痕量金属持续进入河口。将蚬暴露于不同浓度的痕量金属中两周，以评估沿盐度梯度的生物累积过程。分析双壳贝类的身体组织残留，以确定与每种金属相关的生物累积因子，并探讨盐度的影响。由于盐度梯度，观察到各水箱之间存在差异。在完成的实验中，生物体中锌和镉的生物累积机制在高盐度值时更有效。两种金属的生物累积因子均随盐度值的增加呈线性增加。铅和铜在生物体中的生物累积机制似乎取决于两个同时发生的过程：靠近金属输入点和低盐度值。
