Currie Zachary, Prosser Ryan S, Rodriguez-Gil Jose Luis, Mahon Kim, Poirier Dave, Solomon Keith R
Centre for Toxicology, School of Environmental Sciences, University of Guelph, Guelph, Ontario, Canada.
Environ Toxicol Chem. 2015 May;34(5):1178-84. doi: 10.1002/etc.2913. Epub 2015 Apr 7.
In 2011, an alternative formulation of glyphosate (Cúspide 480SL®) was chosen to replace Roundup-SL®, Fuete-SL®, and Gly-41® for the control of Erythroxylum coca, the source of cocaine, in Colombia. Cúspide 480SL contains the active ingredient glyphosate isopropylamine (IPA) salt, which is the same active ingredient used in previous formulations. However, Cúspide 480SL contains an alkyl polyglycoside surfactant rather than the polyethoxylated tallow amine (POEA) surfactant used in other formulations and known to be more toxic to nonprimary producing aquatic organisms than glyphosate itself. An adjuvant, Cosmo-Flux F411, and water also are added to the spray mixture before application. Aquatic ecosystems adjacent to the target coca fields might be exposed to the spray mix, placing aquatic organisms at risk. Because no toxicity data were available for spray mixture on aquatic organisms, acute toxicity tests were conducted on aquatic plants, invertebrates, and fish, by using the Cúspide 480SL spray mix as described on the label. Based on the median effective concentration (EC50) values for similar organisms, the spray mixture was less toxic to aquatic organisms than formulations previously used for the control of coca (i.e., Roundup-SL, Fuete-SL, and Gly-41). A physical effect induced by Cosmo-Flux F411 was observed in Daphnia magna, Ceriodaphnia dubia, and Hyalella azteca, causing the invertebrates to be trapped in an oily film that was present at the surface of the water. However, a hazard assessment for the Cúspide 480SL spray mix, using estimated worst-case exposure scenario concentrations and EC50 values from the toxicity tests, indicated de minimis hazard for the tested aquatic animals, with hazard quotients all <<1.
2011年，哥伦比亚选用了草甘膦的一种替代制剂（Cúspide 480SL®）来取代农达-SL®、Fuete-SL®和Gly-41®，用于控制古柯（可卡因的来源）。Cúspide 480SL含有活性成分草甘膦异丙胺（IPA）盐，这与之前制剂中使用的活性成分相同。然而，Cúspide 480SL含有一种烷基多苷表面活性剂，而非其他制剂中使用的聚乙氧基化牛脂胺（POEA）表面活性剂，已知POEA对非初级生产水生生物的毒性比草甘膦本身更大。在施用前，还会向喷雾混合物中添加一种助剂Cosmo-Flux F411和水。目标古柯田附近的水生生态系统可能会接触到喷雾混合物，从而使水生生物面临风险。由于没有关于喷雾混合物对水生生物的毒性数据，因此使用标签上所述的Cúspide 480SL喷雾混合物，对水生植物、无脊椎动物和鱼类进行了急性毒性试验。根据类似生物的半数有效浓度（EC50）值，该喷雾混合物对水生生物的毒性低于先前用于控制古柯的制剂（即农达-SL、Fuete-SL和Gly-41）。在大型溞、 dubia角突网纹溞和阿氏溪蟹中观察到Cosmo-Flux F411引起的一种物理效应——导致这些无脊椎动物被困在水面上出现的一层油膜中。然而，使用毒性试验中估计的最坏情况暴露情景浓度和EC50值对Cúspide 480SL喷雾混合物进行的危害评估表明，受试水生动物的危害极小，危害商数均远小于1。
