• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Chemosphere >Biodegradation of hydrocarbon mixtures in surface waters at environmentally relevant levels - Effect of inoculum origin on kinetics and sequence of degradation
【24h】

Biodegradation of hydrocarbon mixtures in surface waters at environmentally relevant levels - Effect of inoculum origin on kinetics and sequence of degradation

机译：环境相关水平的地表水中碳氢化合物混合物的生物降解-接种物对动力学和降解顺序的影响

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

Biodegradation is a dominant removal process for many organic pollutants, and biodegradation tests serve as tools for assessing their environmental fate within regulatory risk assessment. In simulation tests, the inoculum is not standardized, varying in microbial quantity and quality, thereby potentially impacting the observed biodegradation kinetics. In this study we investigated the effect of inoculum origin on the biodegradation kinetics of hydrocarbons for five inocula from surface waters varying in urbanization and thus expected pre-exposure to petroleum hydrocarbons. A new biodegradation method for testing mixtures of hydrophobic chemicals at trace concentrations was demonstrated: Aqueous solutions containing 9 hydrocarbons were generated by passive dosing and diluted with surface water resulting in test systems containing native microorganisms exposed to test substances at ng-mu g/L levels. Automated Headspace Solid Phase Microextraction coupled to GC-MS was applied directly to these test systems to determine substrate depletion relative to abiotic controls. Lag phases were generally less than 8 days. First order rate constants were within one order of magnitude for each hydrocarbon in four of the five waters but lower in water from a rural lake. The sequence of degradation between the 9 hydrocarbons showed similar patterns in the five waters indicating the potential for using selected hydrocarbons for benchmarking between biodegradation tests. Degradation half-times were shorter than or within one order of magnitude of BioHCwin predictions for 8 of 9 hydrocarbons. These results showed that location choice is important for biodegradation kinetics and can provide a relevant input to aquatic exposure and fate models. (C) 2017 Elsevier Ltd. All rights reserved.
机译：生物降解是许多有机污染物的主要去除过程，而生物降解测试可作为在监管风险评估中评估其环境命运的工具。在模拟测试中，接种物不是标准化的，微生物数量和质量各不相同，从而可能影响观察到的生物降解动力学。在这项研究中，我们调查了接种物对城市化过程中地表水变化的五种接种物碳氢化合物生物降解动力学的影响，并因此预暴露于石油碳氢化合物。演示了一种新的生物降解方法，用于测试痕量浓度的疏水性化学物质混合物：通过被动加料生成包含9种碳氢化合物的水溶液，并用地表水稀释，从而使包含天然微生物的测试系统暴露于ng-μg / L的测试物质。将与GC-MS耦合的自动顶空固相微萃取直接应用于这些测试系统，以确定相对于非生物对照的底物耗竭。滞后阶段通常少于8天。在五个水域中的四个水中，每种碳氢化合物的一级速率常数均在一个数量级以内，而在农村湖泊的水中则较低。 9种碳氢化合物之间的降解顺序在5种水域中显示出相似的模式，这表明使用选定的碳氢化合物作为生物降解试验基准的潜力。 9种碳氢化合物中有8种的降解半衰期比BioHCwin预测短或短于一个数量级。这些结果表明，位置选择对于生物降解动力学很重要，并且可以为水生暴露和命运模型提供相关输入。 （C）2017 Elsevier Ltd.保留所有权利。

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