...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Environmental Science & Technology >Assessing Dioxin Precursors in Pesticide Formulations and Environmental Samples As a Source of Octachlorodibenzo-p-dioxin in Soil and Sediment
【24h】

Assessing Dioxin Precursors in Pesticide Formulations and Environmental Samples As a Source of Octachlorodibenzo-p-dioxin in Soil and Sediment

机译：评估农药制剂和环境样品中二恶英前体作为土壤和沉积物中八氯二苯并-p-二恶英的来源

获取原文
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

An as yet unidentified origin of elevated concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) in soil and sediment has repeatedly been described from different locations around the world, including Australia. Natural sources have been hypothesized to account for such contamination, which is characterized by a distinctive dioxin profile, in particular, elevated levels of octachlorodibenzo-p-dioxins (OCDD) as well as relatively low contributions of polychlorinated dibenzofurans (PCDFs). The present study investigated whether OCDD formation via anthropogenically derived precursors represents a possible source in such samples. Soil and sediment from Australia and Hawaii were screened for known pesticide derived dioxin precursors. Two pesticide formulations containing pentachlorophenol (PCP), which are well-known to contain predominantly OCDD impurities, were also analyzed. Polychlorinated phenoxyphenols (PCPPs), common byproducts of pesticide production, were detected at parts-per-billion (ppb) levels in two PCP formulations and in five environmental samples. Of particular interest was the presence of the PCPPisomer 3,4,5,6-tetrachloro-2-(2,3,4,5,6-pentachlorophenoxy)phenol(nonaC2PP), often also termed predioxin, in these samples. This compoundrnreadily undergoes ring closure to form OCDD under a range of conditions and environments. In addition, the pesticide PCP itself, which also represents a potent precursor to OCDD formation and is known to contain OCDD impurities, was detected in some environmental samples. The evidence from this study indicates that pesticides and their impurities play an important role in the dioxin contamination of Australian soils and sediments, as well as other locations with similar PCDD/F patterns. The results further suggest that formation of OCDD from pesticide derived precursors may be a possible past present, and future pathway for contamination of environmental samples.
机译：在世界各地，包括澳大利亚，都反复描述了土壤和沉积物中多氯二苯并对二恶英（PCDDs）浓度升高的原因，目前尚未确定。据推测，天然来源可解决这种污染，其特征是独特的二恶英特性，特别是八氯二苯并-p-二恶英（OCDD）的水平升高以及多氯二苯并呋喃（PCDF）的贡献相对较低。本研究调查了通过人为衍生的前体形成OCDD是否代表此类样品的可能来源。从澳大利亚和夏威夷的土壤和沉积物中筛选出已知的农药衍生的二恶英前体。还分析了两种含有五氯苯酚（PCP）的农药配方，众所周知这些农药主要含有OCDD杂质。在两种PCP配方和五个环境样品中，以农药的十亿分之一（ppb）的水平检测到农药生产中常见的副产物多氯苯氧基苯酚（PCPPs）。在这些样品中，PCPP异构体3,4,5,6-四氯-2-（2,3,4,5,6-五氯苯氧基）苯酚（nonaC2PP）的存在通常引起人们的特别关注。该化合物在各种条件和环境下都容易进行闭环形成OCDD。此外，在一些环境样品中还检测到了农药PCP本身，它也是OCDD形成的有效前体，并且已知含有OCDD杂质。这项研究的证据表明，农药及其杂质在澳大利亚土壤和沉积物以及其他具有相似PCDD / F模式的地区的二恶英污染中起着重要作用。结果进一步表明，由农药衍生的前体形成OCDD可能是过去可能存在的，也是将来污染环境样品的途径。

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