Louch Jeff, Tatum Vickie, Allen Ginny, Hale V Cody, McDonnell Jeffrey, Danehy Robert J, Ice George
National Council for Air and Stream Improvement, Corvallis, Oregon, USA.
National Council for Air and Stream Improvement, Newberry, Florida, USA.
Integr Environ Assess Manag. 2017 Mar;13(2):396-409. doi: 10.1002/ieam.1781. Epub 2016 Jul 18.
Glyphosate, aminomethylphosphonic acid (AMPA), imazapyr, sulfometuron methyl (SMM), and metsulfuron methyl (MSM) were measured in streamwater collected during and after a routine application of herbicides to a forestry site in Oregon's Coast Range. Samples were collected at 3 stations: HIGH at the fish-no-fish interface in the middle of the harvest and spray unit, MID at the bottom of the unit, and LOW downstream of the unit. All herbicides were applied by helicopter in a single tank mix. AMPA, imazapyr, SMM, and MSM were not detected (ND) in any sample at 15, 600, 500, and 1000 ng/L, respectively. A pulse of glyphosate peaking at approximately equal to 62 ng/L manifested at HIGH during the application. Glyphosate pulses peaking at 115 ng/L (MID) and 42 ng/L (HIGH) were found during the first 2 postapplication storm events 8 and 10 days after treatment (DAT), respectively: glyphosate was less than 20 ng/L (ND) at all stations during all subsequent storm events. All glyphosate pulses were short-lived (4-12 h). Glyphosate in baseflow was approximately equal to 25 ng/L at all stations 3 DAT and was still approximately equal to 25 ng/L at HIGH, but ND at the other stations, 8 DAT: subsequently, glyphosate was ND in baseflow at all stations. Aquatic organisms were subjected to multiple short-duration, low-concentration glyphosate pulses corresponding to a cumulative time-weighted average (TWA) exposure of 6634 ng/L × h. Comparisons to TWA exposures associated with a range of toxicological endpoints for sensitive aquatic organisms suggests a margin of safety exceeding 100 at the experimental site, with the only potential exception resulting from the ability of fish to detect glyphosate via olfaction. For imazapyr, SMM, and MSM the NDs were at concentrations low enough to rule out effects on all organisms other than aquatic plants, and the low concentration and (assumed) pulsed nature of any exposure should mitigate this potential. Integr Environ Assess Manag 2017;13:396-409. © 2016 SETAC.
在俄勒冈海岸山脉的一个林业场地进行常规除草剂喷洒期间及之后，对采集的溪流水样中的草甘膦、氨甲基膦酸（AMPA）、咪唑乙烟酸、甲磺隆（SMM）和甲基二磺隆（MSM）进行了测定。在3个站点采集了样本：位于采伐和喷洒区域中部鱼类生存与无鱼区域交界处的高位站点（HIGH）、位于该区域底部的中位站点（MID）以及该区域下游的低位站点（LOW）。所有除草剂均通过直升机以单罐混合的方式进行喷洒。在任何样本中，AMPA、咪唑乙烟酸、SMM和MSM的检测限分别为15、600、500和1000纳克/升，均未检测到（ND）。喷洒期间，高位站点出现了一个草甘膦脉冲，峰值约为62纳克/升。在处理后第8天和第10天的前两次降雨事件期间，分别在中位站点（峰值为115纳克/升）和高位站点（峰值为42纳克/升）发现了草甘膦脉冲：在所有后续降雨事件期间，所有站点的草甘膦浓度均低于20纳克/升（未检测到）。所有草甘膦脉冲持续时间都很短（4 - 12小时）。处理后第3天，所有站点基流中的草甘膦浓度约为25纳克/升，处理后第8天，高位站点的草甘膦浓度仍约为25纳克/升，其他站点未检测到：随后，所有站点基流中的草甘膦均未检测到。水生生物受到了多次短时间、低浓度的草甘膦脉冲影响，累积时间加权平均（TWA）暴露量为6634纳克/升·小时。与敏感水生生物一系列毒理学终点相关的TWA暴露量进行比较表明，实验场地的安全系数超过100，唯一可能的例外是鱼类通过嗅觉检测草甘膦的能力。对于咪唑乙烟酸、SMM和MSM，未检测到的浓度低到足以排除对除水生植物以外的所有生物的影响，并且任何暴露的低浓度和（假定的）脉冲性质应可减轻这种潜在影响。《综合环境评估与管理》2017年；13:396 - 409。© 2016 SETAC。
