Department of Biology and Environmental Science and Department of Physics, University of New Haven, 300 Boston Post Road, West Haven, Connecticut 06516, USA.
Environ Sci Technol. 2009 Dec 15;43(24):9473-9. doi: 10.1021/es901695c.
The effects of five nanomaterials (multiwalled carbon nanotubes [MWCNTs], Ag, Cu, ZnO, Si) and their corresponding bulk counterparts on seed germination, root elongation, and biomass of Cucurbita pepo (zucchini) were investigated. The plants were grown in hydroponic solutions amended with nanoparticles or bulk material suspensions at 1000 mg/L. Seed germination was unaffected by any of the treatments, but Cu nanoparticles reduced emerging root length by 77% and 64% relative to unamended controls and seeds exposed to bulk Cu powder, respectively. During a 15-day hydroponic trial, the biomass of plants exposed to MWCNTs and Ag nanoparticles was reduced by 60% and 75%, respectively, as compared to control plants and corresponding bulk carbon and Ag powder solutions. Although bulk Cu powder reduced biomass by 69%, Cu nanoparticle exposure resulted in 90% reduction relative to control plants. Both Ag and Cu ion controls (1-1000 mg/L) and supernatant from centrifuged nanoparticle solutions (1000 mg/L) indicate that half the observed phytotoxicity is from the elemental nanoparticles themselves. The biomass and transpiration volume of zucchini exposed to Ag nanoparticles or bulk powder at 0-1000 mg/mL for 17 days was measured. Exposure to Ag nanoparticles at 500 and 100 mg/L resulted in 57% and 41% decreases in plant biomass and transpiration, respectively, as compared to controls or to plants exposed to bulk Ag. On average, zucchini shoots exposed to Ag nanoparticles contained 4.7 greater Ag concentration than did the plants from the corresponding bulk solutions. These findings demonstrate that standard phytotoxicity tests such as germination and root elongation may not be sensitive enough or appropriate when evaluating nanoparticle toxicity to terrestrial plant species.
研究了五种纳米材料（多壁碳纳米管[MWCNTs]、Ag、Cu、ZnO、Si）及其相应的体相材料对南瓜（西葫芦）种子萌发、根伸长和生物量的影响。将植物在 1000mg/L 的纳米颗粒或体相材料悬浮液的水培溶液中生长。任何处理都不会影响种子的萌发，但 Cu 纳米颗粒使萌发的根长相对于未处理对照和暴露于体相 Cu 粉末的种子分别减少了 77%和 64%。在为期 15 天的水培试验中，与对照植物和相应的体相碳和 Ag 粉末溶液相比，暴露于 MWCNTs 和 Ag 纳米颗粒的植物生物量分别减少了 60%和 75%。虽然体相 Cu 粉末使生物量减少了 69%，但暴露于 Cu 纳米颗粒的植物生物量减少了 90%。Ag 和 Cu 离子对照（1-1000mg/L）和离心纳米颗粒溶液的上清液（1000mg/L）表明，观察到的一半植物毒性来自元素纳米颗粒本身。将西葫芦暴露于 Ag 纳米颗粒或体相粉末在 0-1000mg/mL 下 17 天，测量其生物量和蒸腾量。与对照或暴露于体相 Ag 的植物相比，暴露于 500 和 100mg/L 的 Ag 纳米颗粒分别导致植物生物量和蒸腾量减少 57%和 41%。平均而言，暴露于 Ag 纳米颗粒的西葫芦芽中 Ag 的浓度比相应体相溶液中的植物高 4.7 倍。这些发现表明，在评估纳米颗粒对陆生植物物种的毒性时，标准的植物毒性试验（如发芽和根伸长）可能不够敏感或不适合。
