Kennedy I R, Sánchez-Bayo F, Kimber S W, Hugo L, Ahmad N
Australian Cotton Cooperative Research Centre, Dep of Agricultural Chemistry & Soil Science, The Univ of Sydney, NSW.
J Environ Qual. 2001 May-Jun;30(3):683-96. doi: 10.2134/jeq2001.303683x.
The fate and transport of endosulfan (6,7,8,9,10,10-hexachloro-1,5, 5a,6,9,9a-hexahydro-6,9-methano-2,4,3-benzodioxathiepin 3-oxide) applied to cotton (Gossypium hirsutum L.) fields were studied throughout three consecutive years on two selected locations in New South Wales (Australia). Rates of dissipation from foliage and soil, volatilization from the field, and transport of residues in irrigation and/or storm runoff waters were measured in order to estimate a total field balance. Dissipation of endosulfan from both foliage and soil is best explained by a two-phase process rather than by a first-order decay. Half-lives of total endosulfan toxic residues (alpha- and beta-endosulfan and the sulfate product) in the first phase were 1.6 d in foliage and 7.1 d in soil, and could be explained by the rapid volatilization of the parent isomers in the first 5 d (up to 70% of endosulfan volatilizes). In the second phase, half-lives were 9.5 d in foliage and 82 d in soil, mostly due to the persistence of the sulfate product. Concentration of endosulfan residues in runoff water varied from 45 to 2.5 microg L(-1) depending on the residue levels present on field soil at the time of the irrigation or storm events. These in turn are related to the total amounts applied, the cotton canopy cover at application, and the time since last spraying. Most of the endosulfan in runoff was found in the water phase (80%), suggesting it was bound to colloidal matter. Total endosulfan residues in runoff for a whole season accounted for no more than 2% of the pesticide applied on-field.
在澳大利亚新南威尔士州的两个选定地点，连续三年研究了施用于棉田（陆地棉）的硫丹（6,7,8,9,10,10 - 六氯 - 1,5,5a,6,9,9a - 六氢 - 6,9 - 亚甲基 - 2,4,3 - 苯并二氧硫杂环庚烷3 - 氧化物）的归宿和迁移情况。测定了硫丹从叶片和土壤中的消散速率、田间挥发速率以及灌溉水和/或暴雨径流水中残留的迁移情况，以估算田间总平衡。硫丹从叶片和土壤中的消散情况用两阶段过程来解释比用一级衰变更好。第一阶段硫丹总有毒残留（α - 和β - 硫丹及硫酸盐产物）在叶片中的半衰期为1.6天，在土壤中为7.1天，这可以用母体异构体在前5天的快速挥发来解释（高达70%的硫丹挥发）。在第二阶段，半衰期在叶片中为9.5天，在土壤中为82天，主要是由于硫酸盐产物的持久性。径流水中硫丹残留浓度在45至2.5微克/升之间变化，这取决于灌溉或暴雨事件发生时田间土壤中的残留水平。这些残留水平又与施用量、施用时棉花冠层覆盖情况以及上次喷洒后的时间有关。径流中大部分硫丹存在于水相中（80%），表明它与胶体物质结合。整个季节径流中硫丹总残留量占田间施用农药量的比例不超过2%。
