NERC Centre for Ecology & Hydrology, Benson Lane, Crowmarsh Gifford, Wallingford, OX10 8BB, UK.
Department of Environmental Engineering, Technical University of Denmark, Miljoevej, building 113, 2800, Kgs Lyngby, Denmark.
Environ Sci Pollut Res Int. 2016 Mar;23(5):4120-8. doi: 10.1007/s11356-015-4538-z. Epub 2015 Apr 24.
Zinc oxide nanoparticles (ZnO NPs) are used in an array of products and processes, ranging from personal care products to antifouling paints, textiles, food additives, antibacterial agents and environmental remediation processes. Soils are an environment likely to be exposed to manmade nanoparticles due to the practice of applying sewage sludge as a fertiliser or as an organic soil improver. However, understanding on the interactions between soil properties, nanoparticles and the organisms that live within soil is lacking, especially with regards to soil bacterial communities. We studied the effects of nanoparticulate, non-nanoparticulate and ionic zinc (in the form of zinc chloride) on the composition of bacterial communities in soil with a modified pH range (from pH 4.5 to pH 7.2). We observed strong pH-dependent effects on the interaction between bacterial communities and all forms of zinc, with the largest changes in bacterial community composition occurring in soils with low and medium pH levels (pH 4.8 and 5.9). The high pH soil (pH 7.2) was less susceptible to the effects of zinc exposure. At the highest doses of zinc (2500 mg/kg dw soil), both nano and non-nano particulate zinc applications elicited a similar response in the soil bacterial community, and this differed significantly to the ionic zinc salt treatment. The results highlight the importance of considering soil pH in nanotoxicology studies, although further work is needed to determine the exact mechanisms controlling the toxicity and fate and interactions of nanoparticles with soil microbial communities.
氧化锌纳米颗粒（ZnO NPs）被广泛应用于各种产品和工艺中，包括个人护理产品、防污涂料、纺织品、食品添加剂、抗菌剂和环境修复过程。由于将污水污泥作为肥料或有机土壤改良剂进行应用，因此土壤可能会接触到人造纳米颗粒。然而，人们对于土壤性质、纳米颗粒与土壤中生存的生物之间的相互作用的理解还很缺乏，尤其是在土壤细菌群落方面。我们研究了纳米颗粒、非纳米颗粒和离子态锌（以氯化锌的形式）对具有改良 pH 值范围（pH4.5 至 pH7.2）的土壤中细菌群落组成的影响。我们观察到，细菌群落与所有形式的锌之间的相互作用强烈依赖于 pH 值，在 pH 值较低和中等的土壤中（pH4.8 和 5.9），细菌群落组成的变化最大。高 pH 值土壤（pH7.2）对锌暴露的影响不太敏感。在锌的最高剂量（2500mg/kg 干土）下，纳米和非纳米颗粒状锌的应用在土壤细菌群落中引起了相似的反应，这与离子态锌盐处理有显著差异。研究结果强调了在纳米毒理学研究中考虑土壤 pH 值的重要性，尽管还需要进一步的工作来确定控制毒性和纳米颗粒在土壤微生物群落中的归宿和相互作用的具体机制。
