Jain Navin, Bhargava Arpit, Pareek Vikram, Sayeed Akhtar Mohd, Panwar Jitendra
Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, 333031, India.
Department of Botany, Gandhi Faiz-E-Aam College, Shahjahanpur, 242001, India.
Ecotoxicology. 2017 Mar;26(2):238-249. doi: 10.1007/s10646-017-1758-7. Epub 2017 Jan 12.
Rapid utilization of nano-based products will inevitably release nanoparticles into the environment with unidentified consequences. Plants, being an integral part of ecosystem play a vital role in the incorporation of nanoparticles in food chain and thus, need to be critically assessed. The present study assesses the comparative phytotoxicity of nanoparticle, bulk and ionic forms of zinc at different concentrations on selected plant species with varying seed size and surface anatomy. ZnO nanoparticles were chosen in view of their wide spread use in cosmetics and health care products, which allow their direct release in the environment. The impact on germination rate, shoot & root length and vigour index were evaluated. A concentration dependent inhibition of seed germination as well as seedling length was observed in all the tested plants. Due to the presence of thick cuticle on testa and root, pearl millet (xerophytic plant) was found to be relatively less sensitive to ZnO nanoparticles as compared to wheat and tomato (mesophytic plants) with normal cuticle layer. No correlation was observed between nanoparticles toxicity and seed size. The results indicated that variations in surface anatomy of seeds play a crucial role in determining the phytotoxicity of nanoparticles. The present findings significantly contribute to assess potential consequences of nanoparticle release in environment particularly with major emphasis on plant systems. It is the first report which suggests that variations observed in phytotoxicity of nanoparticles is mainly due to the predominant differences in size and surface anatomy of tested plant seeds and root architecture. Effect of various concentrations of nano ZnO, bulk ZnO and zinc sulphate on the growth of pearl millet (A), tomato (B) and wheat (C) seedlings.
纳米基产品的快速应用将不可避免地把纳米颗粒释放到环境中，其后果尚不明晰。植物作为生态系统的一个组成部分，在纳米颗粒融入食物链过程中起着至关重要的作用，因此需要进行严格评估。本研究评估了不同浓度的锌纳米颗粒、块状锌和离子形式的锌对具有不同种子大小和表面解剖结构的选定植物物种的相对植物毒性。鉴于氧化锌纳米颗粒在化妆品和保健产品中的广泛应用，使其能够直接释放到环境中，故选择了氧化锌纳米颗粒。评估了其对发芽率、茎和根长度以及活力指数的影响。在所有测试植物中均观察到种子萌发以及幼苗长度受到浓度依赖性抑制。由于黍（旱生植物）的种皮和根上有较厚的角质层，与具有正常角质层的小麦和番茄（中生植物）相比，发现黍对氧化锌纳米颗粒相对不那么敏感。未观察到纳米颗粒毒性与种子大小之间的相关性。结果表明，种子表面解剖结构的差异在决定纳米颗粒的植物毒性方面起着关键作用。本研究结果对评估纳米颗粒释放到环境中的潜在后果具有重要意义，特别是主要关注植物系统。这是第一份表明纳米颗粒植物毒性差异主要是由于受试植物种子的大小和表面解剖结构以及根系结构的主要差异所致的报告。不同浓度的纳米氧化锌、块状氧化锌和硫酸锌对黍（A）、番茄（B）和小麦（C）幼苗生长的影响。
