Chen Yuanzhen, Si Youbin, Zhou Dongmei, Dang Fei
Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008 China; School of Resources and Environment, Anhui Agricultural University, Hefei, 230036, China.
School of Resources and Environment, Anhui Agricultural University, Hefei, 230036, China.
Environ Pollut. 2017 Mar;222:50-57. doi: 10.1016/j.envpol.2017.01.007. Epub 2017 Jan 12.
With the increasing application in antimicrobial products, silver nanoparticles (AgNP) are inevitably released into the terrestrial environment, and pose potential risks to invertebrates such as land snails Achatina fulica, which take up AgNP from food and water. Here we differentiate Ag uptake biodynamic between Ag forms (i.e., PVP-AgNP vs. AgNO) and between exposure pathways. Snails assimilated Ag efficiently from lettuce leaves pre-exposed to AgNP, with assimilation efficiencies (AEs) averaging 62-85% and food ingestion rates of 0.11 ± 0.03 g g d. Dietary Ag bioavailability was independent on Ag forms, as revealed by comparable AEs between AgNP and AgNO. However, the uptake rate constant from water was much lower for AgNP relative to AgNO (2 × 10 vs. 0.12 L g d). The elimination rate constants were 0.0093 ± 0.0037 d for AgNP and 0.019 ± 0.0077 d for AgNO. Biodynamic modeling further showed that dietary exposure was the dominant uptake pathway for AgNP in most circumstances, while for AgNO the relative importance of waterborne and dietary exposure depended on Ag concentrations in food and water. Our findings highlight the importance of dietary uptake of AgNP during bioaccumulation, which should be considered in the risk assessment of these nanoparticles.
随着银纳米颗粒（AgNP）在抗菌产品中的应用日益增加，它们不可避免地释放到陆地环境中，并对诸如非洲大蜗牛等无脊椎动物构成潜在风险，这些无脊椎动物会从食物和水中摄取AgNP。在此，我们区分了不同Ag形态（即聚乙烯吡咯烷酮包覆的银纳米颗粒与硝酸银）以及不同暴露途径下Ag的吸收生物动力学。蜗牛能有效地从预先暴露于AgNP的生菜叶中同化Ag，同化效率（AE）平均为62 - 85%，食物摄取率为0.11±0.03 g g⁻¹ d⁻¹。正如AgNP和硝酸银之间可比的同化效率所表明的，膳食中Ag的生物有效性与Ag形态无关。然而，相对于硝酸银，AgNP从水中的摄取速率常数要低得多（2×10⁻⁴ 与0.12 L g⁻¹ d⁻¹）。AgNP的消除速率常数为0.0093±0.0037 d⁻¹，硝酸银的消除速率常数为0.019±0.0077 d⁻¹。生物动力学模型进一步表明，在大多数情况下，膳食暴露是AgNP的主要摄取途径，而对于硝酸银，水暴露和膳食暴露的相对重要性取决于食物和水中的Ag浓度。我们的研究结果突出了生物累积过程中膳食摄取AgNP的重要性，在这些纳米颗粒的风险评估中应予以考虑。
