University of Florida/IFAS Indian River Research and Education Center (Soil and Water Science Department), 2199 South Rock Road, Fort Pierce, FL 34945, USA.
Sci Total Environ. 2011 Dec 15;412-413:119-26. doi: 10.1016/j.scitotenv.2011.09.058. Epub 2011 Oct 27.
Much uncertainty exists regarding the discharge characteristics of terrestrial-use herbicides into aquatic systems. This study evaluated the temporal distribution and concentrations of five commonly used herbicides (atrazine, bromacil, metolachlor, norflurazon, and simazine) in a typical South Florida watershed. Surface water samples were collected weekly over a 3-yr period from four canals and Ten Mile Creek. These systems received drainage water from a variety of land-uses, including residential, pastures, and citrus production. Herbicides were extracted and analyzed by GC-MS/SIM. Atrazine was most frequently detected (87% of samples) in the canal serving the residentially developed sub-basin, with median and maximum concentrations of 0.43 and 6.67 μg L(-1), respectively. Norflurazon was most frequently detected (90-95% of samples) in the systems serving agricultural production areas, with median and maximum concentrations ranging from 0.37-0.63 μg L(-1) and 1.98-6.97 μg L(-1), respectively. Bromacil was detected in 14-36% of samples with median and maximum concentrations ranging from 0.50-0.67 μg L(-1) and 2.31-4.96 μg L(-1), respectively. Metolachlor was detected in 1.8-10% of the samples, with median and maximum concentrations ranging from 0.16-0.2 μgL(-1) and 0.17-1.55 μg L(-1), respectively. Simazine was detected in 10-35% of the samples, with median and maximum concentrations ranging from 0.18-0.28 μg L(-1) and 0.37-1.35 μg L(-1), respectively. Bromacil+norflurazon was the most commonly detected (240 samples of 1060 total) binary combination of herbicides; whereas bromacil+norflurazon+simazine was the most frequently detected tertiary combination (58 samples). While detectable concentrations were present for significant periods of time, risks of acute toxicity were relatively low; affecting <1% of the potentially affected fraction (PAF) of plant species based on 90th centile exposure concentrations and 10th centile effects concentrations from species sensitivity distributions.
关于陆生除草剂排放到水生系统中的特性存在很多不确定性。本研究评估了在南佛罗里达州一个典型流域中 5 种常用除草剂（莠去津、溴苯腈、甲草胺、氟磺胺草醚和西玛津）的时间分布和浓度。在 3 年期间，每周从 4 条运河和 10 英里溪采集地表水样本。这些系统接收来自各种土地利用的排水，包括住宅、牧场和柑橘种植。使用 GC-MS/SIM 提取和分析除草剂。在为居民区开发的亚流域服务的运河中，莠去津最常被检测到（87%的样本），其中位数和最大值浓度分别为 0.43 和 6.67μg/L。在为农业生产区服务的系统中，氟磺胺草醚最常被检测到（90-95%的样本），其中位数和最大值浓度范围分别为 0.37-0.63μg/L 和 1.98-6.97μg/L。溴苯腈在 14-36%的样本中被检测到，其中位数和最大值浓度范围分别为 0.50-0.67μg/L 和 2.31-4.96μg/L。甲草胺在 1.8-10%的样本中被检测到，其中位数和最大值浓度范围分别为 0.16-0.2μgL(-1)和 0.17-1.55μg/L。西玛津在 10-35%的样本中被检测到，其中位数和最大值浓度范围分别为 0.18-0.28μg/L 和 0.37-1.35μg/L。溴苯腈+氟磺胺草醚是检测到的最常见的（1060 个样本中的 240 个）除草剂二元组合；而溴苯腈+氟磺胺草醚+西玛津是检测到的最常见的三元组合（58 个样本）。虽然在很长一段时间内都存在可检测浓度，但急性毒性的风险相对较低；根据物种敏感性分布的 90 百分位暴露浓度和 10 百分位效应浓度，影响不到 1%的潜在受影响物种部分（PAF）。
