Environmental Laboratory, US Army Engineer Research and Development Center, Vicksburg, MS, USA.
Environ Toxicol Chem. 2013 Sep;32(9):2069-77. doi: 10.1002/etc.2278. Epub 2013 Jul 12.
As the production and applications of silver nanoparticles (AgNPs) increase, it is essential to characterize fate and effects in environmental systems. Nanosilver materials may settle from suspension; therefore, the authors' objective was to utilize environmentally relevant bioassays and study the impact, bioaccumulation, tissue distribution, uptake, and depuration of AgNPs on a sediment-dwelling invertebrate, Lumbriculus variegatus. Hydrodynamic diameters of uncoated 30-nm, 80-nm, and 1500-nm AgNP powders and a polyvinyl pyrrolidone (PVP) AgNP suspension were measured utilizing dynamic light scattering in freshwater media (0-280 µS/cm). Aggregation for 30 nm, 80 nm, and 1500 nm silver increased with conductivity but was minimal for PVP silver. Lumbriculus variegatus were exposed to AgNPs or silver nitrate (AgNO3 ) spiked into sediment (nominally 100 mg/kg) and water (PVP 30 nm and 70 nm Ag, nominally 5 mg/L). Uptake was assessed through inductively coupled plasma mass spectroscopy (ICP-MS) and hyperspectral imaging. Particle sizes were examined through field flow fractionation-ICP-MS (FFF-ICP-MS) and ICP-MS in single particle mode (SP-ICP-MS). Lumbriculus variegatus were also depurated for 6 h, 8 h, 24 h, and 48 h to determine gut clearance. Bioaccumulation factors of sediment-exposed L. variegatus were similar regardless of particle size or coatings. The FFF-ICP-MS and SP-ICP-MS detected AgNPs for up to 48 h post depuration. The present study provides information on bioaccumulation and interactions of AgNPs within biological systems.
随着银纳米粒子(AgNPs)的生产和应用增加,对其在环境系统中的归宿和效应进行特征描述至关重要。纳米银材料可能会从悬浮液中沉降;因此,作者的目的是利用具有环境相关性的生物测定法研究沉降在沉积物中的底栖无脊椎动物——赤子爱胜蚓对纳米银的影响、生物累积、组织分布、摄取和排泄。在淡水介质(0-280 µS/cm)中,利用动态光散射法测量了未涂层的 30nm、80nm 和 1500nm AgNP 粉末以及聚乙烯吡咯烷酮(PVP)AgNP 悬浮液的水动力学直径。30nm、80nm 和 1500nm 银的团聚随电导率的增加而增加,但 PVP 银的团聚最小。赤子爱胜蚓暴露于 AgNPs 或添加到沉积物(名义上 100mg/kg)和水中(PVP 30nm 和 70nm Ag,名义上 5mg/L)的硝酸银(AgNO3)中。通过电感耦合等离子体质谱(ICP-MS)和高光谱成像评估摄取量。通过场流分级-ICP-MS(FFF-ICP-MS)和单颗粒模式 ICP-MS(SP-ICP-MS)检查颗粒尺寸。赤子爱胜蚓还进行了 6h、8h、24h 和 48h 的净化,以确定肠道清除率。无论颗粒大小或涂层如何,暴露于沉积物中的赤子爱胜蚓的生物累积因子都相似。在净化后 48 小时内,FFF-ICP-MS 和 SP-ICP-MS 都检测到了 AgNPs。本研究提供了有关 AgNPs 在生物系统中生物累积和相互作用的信息。