Patton Gregory, Dauble Dennis, McKinstry Craig
Environmental Technology Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA.
Environ Monit Assess. 2007 Oct;133(1-3):285-94. doi: 10.1007/s10661-006-9583-0. Epub 2007 Feb 10.
We conducted a laboratory evaluation to assess the risk to early life stage (i.e., eyed egg to swim up) fall Chinook salmon (Oncorhynchus tshawytscha) for exposure to hexavalent chromium from a contaminated groundwater source. Local populations of fall Chinook salmon were exposed to Hanford Site source groundwater that was diluted with Columbia River water. Specific endpoints included survival, development rate, and growth. Tissue burdens of fish were also measured to estimate uptake and elimination rates of chromium. Survival, development, and growth of early life stage fall Chinook salmon were not adversely affected by extended exposures (i.e., 98 day) to hexavalent chromium ranging from 0.79 to 260 microg/l. Survival for all treatment levels and controls exceeded 98% at termination of the test. In addition, there were no differences among the mean lengths and weights of fish among all treatment groups. Whole-body concentrations of chromium in early life stage fall Chinook salmon had a typical dose-response pattern; i.e., those subjected to highest exposure concentrations and longest exposure intervals had higher tissue concentrations. Given the spatial extent of chromium concentrations at the Hanford Site, and the dynamics of the groundwater-river water interface, the current cleanup criterion of 10 microg/l chromium appear adequate to protect early life stage fall Chinook salmon. These findings, together with previous research indicate low risk to these populations.
我们进行了一项实验室评估，以评估受污染地下水源中的六价铬对幼年期（即从眼卵到上浮阶段）秋季奇努克鲑（Oncorhynchus tshawytscha）的风险。秋季奇努克鲑的本地种群接触了用哥伦比亚河水稀释的汉福德场地源地下水。具体的终点指标包括存活率、发育率和生长情况。还测量了鱼的组织负荷，以估计铬的摄取和消除率。幼年期秋季奇努克鲑的存活、发育和生长并未因长期暴露（即98天）于浓度范围为0.79至260微克/升的六价铬而受到不利影响。在试验结束时，所有处理水平和对照组的存活率均超过98%。此外，所有处理组之间鱼的平均长度和重量没有差异。幼年期秋季奇努克鲑体内铬的全身浓度呈现典型的剂量反应模式；即，暴露于最高浓度和最长暴露时间的鱼组织浓度更高。鉴于汉福德场地铬浓度的空间范围以及地下水与河水界面的动态变化，目前10微克/升铬的清理标准似乎足以保护幼年期秋季奇努克鲑。这些发现与之前的研究表明这些种群面临的风险较低。
