USGS Oregon Water Science Center, Portland, OR, USA.
USGS California Water Science Center, Sacramento, CA, USA.
Arch Environ Contam Toxicol. 2023 Apr;84(3):307-317. doi: 10.1007/s00244-023-00981-8. Epub 2023 Mar 13.
Naled, an organophosphate insecticide, is applied aerially at ultra-low volumes over aquatic ecosystems near Sacramento, California, USA, during summer months for mosquito control. Two ecosystem types (rice fields and a flowing canal) were sampled in 2020 and 2021. Naled and its primary degradation product (dichlorvos) were measured in water, biofilm, grazer macroinvertebrates, and omnivore/predator macroinvertebrates (predominantly crayfish). Maximum naled and dichlorvos concentrations detected in water samples one day after naled application were 287.3 and 5647.5 ng/L, respectively, which were above the U.S. Environmental Protection Agency's aquatic life benchmarks for invertebrates. Neither compound was detected in water more than one day after the application. Dichlorvos, but not naled, was detected in composite crayfish samples up to 10 days after the last aerial application. Detections in water from the canal showed that the compounds were transported downstream of the target application area. Factors such as vector control flight paths, dilution, and transport through air and water likely affected concentrations of naled and dichlorvos in water and organisms from these aquatic ecosystems.
纳莱，一种有机磷杀虫剂，在美国加利福尼亚州萨克拉门托附近的水生生态系统中，夏季以超低容量进行空中喷洒，用于控制蚊子。在 2020 年和 2021 年，对两种生态系统类型（稻田和流动运河）进行了采样。在水样、生物膜、食草大型无脊椎动物和杂食/捕食性大型无脊椎动物（主要是小龙虾）中测量了纳莱及其主要降解产物（敌敌畏）。在纳莱施药后一天采集的水样中，检测到的纳莱和敌敌畏的最高浓度分别为 287.3 和 5647.5ng/L，均高于美国环境保护署对无脊椎动物的水生生物基准值。施药后一天以上的水样中均未检测到这两种化合物。在最后一次空中喷洒后长达 10 天的时间里，在复合小龙虾样本中检测到了敌敌畏，但未检测到纳莱。来自运河的水样检测结果表明，这些化合物被运移到了目标应用区域的下游。控制向量的飞行路径、稀释以及通过空气和水的运输等因素可能会影响这些水生生态系统中的水和生物体内纳莱和敌敌畏的浓度。
