单甲酸盐 (MSMA) 的环境命运-第1部分:概念模型
Michal Eldan1, Yoko Masue-Slowey2
1Luxembourg Industries Ltd., The Organic Arsenical Products Task Force, Washington, District of Columbia, USA.
Integrated environmental assessment and management
|June 26, 2024
概括
单甲 (MSMA) 除草剂分解成与土壤强烈结合的成分,减少地下水污染. 微生物活动和土壤条件影响MSMA及其代谢物的转化和固定.
科学领域:
- 环境化学环境化学
- 土壤科学 土壤科学
- 生态毒理学 生态毒理学
背景情况:
- 单甲松酸盐 (MSMA) 是一种广泛使用的除草剂,用于棉花和草的杂草控制.
- 在水中,MSMA分解成离子和单甲基氨酸 (MMA),这是活性除草剂成分.
- 土壤微生物将MMA转化为二甲基酸 (DMA) 和无机 (iAs).
研究的目的:
- 综合现有关于MSMA环境行为的研究.
- 在典型的使用条件下提供MSMA命运的可靠预测.
- 了解影响地下水中无机 (IA) 度的过程.
主要方法:
- 文献综述综合了有关MSMA环境行为相关研究的结果.
- 分析影响MMA及其代谢物的吸收和转化因素.
- 环境过程的建模,以预测土壤中的命运.
主要成果:
- 土壤中MMA的命运主要由微生物活动和对土壤表面的吸附控制.
- 无机 (iAs) 呈现出比MMA更广泛的吸收.
- 诸如通风,温度,pH值和营养物质的可用性等因素影响MSMA的转化和吸收.
- 随着时间的推移,MSMA及其代谢物变得越来越不动,并在土壤基质中被隔离.
结论:
- 由于强烈的吸收,MSMA及其代谢物 (MMA,iAs) 在土壤中变得基本不动.
- 这种固定限制了微生物活动和漏到地下水.
- 特定地点的条件影响这些过程,但在高度管理的MSMA应用领域受到限制.
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