...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Environmental toxicology and chemistry >Water quality guidance for protection of freshwater mussels (unionidae) from ammonia exposure.
【24h】

Water quality guidance for protection of freshwater mussels (unionidae) from ammonia exposure.

机译：防止淡水贻贝（鱼类）接触氨的水质指南。

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Ammonia toxicity data for freshwater mussels (Unionidae), a significantly imperiled taxa, were used to derive estimates of concentrations that would not likely be harmful in acute and chronic exposures and to assess the protectiveness of current U.S. Environmental Protection Agency (U.S. EPA) water quality criteria to this family of organisms. Thirty acute (24-96-h) median lethal concentrations (LC50s), covering 10 species in eight unionid genera, were used to calculate genus mean acute values (GMAVs) ranging from 2.56 to 8.97 mg/L total ammonia as N at pH 8. Freshwater mussels are at the sensitive end of the range when added to the GMAVs from the database used to derive the U.S. EPA criteria maximum concentration (CMC). We derived two estimates of acute exposure water quality guidance for the protection of freshwater mussels (CMC(FM)) by a recalculation of the CMC after adding freshwater mussel GMAVs to the U.S. EPA data set. The CMC(FM)s of 1.75 and 2.50 mg/L total ammonia as N at pH 8 average 60% less than the U.S. EPA CMC of 5.62 mg/L total ammonia as N at pH 8 for application when salmonids are present. These values average about 75% less than the CMC for application when salmonids are absent. No chronic ammonia exposure data existed for unionids. Thus, we applied a range of estimated acute:chronic ratios to the acute toxicity data set, expanded with the freshwater mussel GMAVs. to estimate continuous ammonia concentrations that may be protective of freshwater mussels. These estimates ranged from 0.3 to 1.0 mg/L total ammonia as N at pH 8, about 20 to 75% less than the U.S. EPA criteria continuous concentration (CCC) of 1.24 mg/L total ammonia as N at pH 8 and 25 degrees C. The current numeric criteria for ammonia may not be protective of mussels, more than half of whose nearly 300 species are in decline in North America. While the CMC(FM) and CCC(FM) are not equivalent to revised U.S. EPA criteria, they are offered as interim guidance for the protection of freshwater mussels.
机译：淡水贻贝（尤尼科）的氨毒性数据被用于严重破坏分类单元，用于得出在急性和慢性暴露中不太可能有害的浓度估算值，并评估当前美国环境保护局（US EPA）水质的保护性这个生物家族的标准。 30个急性（24-96-h）致死浓度中位数（LC50），涵盖8个union虫属的10个物种，用于计算pH为8时，总氨的类属平均急性值（GMAV）为2.56至8.97 mg / L。当从用于得出美国EPA标准最大浓度（CMC）的数据库添加到GMAV中时，淡水贻贝处于该范围的敏感端。在将淡水贻贝GMAV添加到美国EPA数据集中后，我们通过重新计算CMC得出了用于保护淡水贻贝（CMC（FM））的急性暴露水质指导的两个估计值。当存在鲑鱼类时，在pH 8时总氮含量为1.75和2.50 mg / L的CMC（FM）比在pH 8时总氮含量为5.62 mg / L的美国EPA CMC平均要低60％。这些值比没有鲑鱼时的CMC平均少约75％。没有针对工会会员的长期氨暴露数据。因此，我们对急性毒性数据集应用了一系列估计的急性：慢性比率，并用淡水贻贝GMAV进行了扩展。估计可能保护淡水贻贝的连续氨浓度。这些估算值在pH 8时为N的总氨含量为0.3到1.0 mg / L，比在pH 8和25摄氏度时为US N的1.24 mg / L N的连续浓度（CCC）低约20至75％。目前关于氨的数字标准可能无法保护贻贝，在北美，贻贝的近300种物种中有一半以上处于下降状态。尽管CMC（FM）和CCC（FM）不等同于美国EPA修订标准，但它们被提供作为保护淡水贻贝的临时指南。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号