Hazards of nanoparticles to the environment and human health

纳米技术是一门涉及在纳米尺度上操纵材料和创造设备的科学。这些过程通常产生纳米颗粒和其他纳米结构，如纳米管和纳米棒，其一个或多个尺寸为100纳米或更小，经合成后具有特殊的特性，用于特定的应用。纳米技术被描述为下一次技术革命，但也引发了人们对纳米颗粒可能损害人类或生物圈的担忧。导致纳米颗粒新特性的相同因素很可能是它们潜在危险的来源。纳米颗粒的效力是由于它们的反应性随着其尺寸的减小而增加，这是由于颗粒变小时表面与体积比增加的结果。因此，纳米颗粒通常具有增强的功能，但在纳米尺度上，散装形式的良性材料可能是危险的。此外，纳米级的颗粒物更有可能被吸入、摄取或吸收，意外暴露的风险也会增加。纳米粒子目前被用于200多种商业产品，包括防晒霜、面霜、化妆品、织物涂层、电子产品、杀生剂和药物输送系统，并不可避免地通过制造排放、意外溢出或使用进入环境。工程纳米颗粒的环境行为目前尚不清楚，它们对人类健康的潜在危害是一个主要问题。在这个概念验证项目中，我们建议通过研究两种目前广泛使用和未来应用潜力的工程纳米材料的反应性，启动对纳米颗粒在吸入和可能进入血流后的行为的调查：多壁碳纳米管和二氧化钛纳米颗粒，与合成肺衬里液体和血浆一起。我们将测试它们的物理性质、大小、形状和结构如何影响它们在溶液中的行为，特别是它们在两种介质中的溶解度、比表面积、表面电荷、表面粗糙度和团聚倾向，旨在模拟血浆(模拟体液)和肺衬液(模拟肺部分泌物)。这项工作完成后，最活跃和最不活跃的颗粒将与原代人类肺细胞和细胞系进行测试，以获得概念验证信息，以确定最活跃的颗粒是否也往往对参与保护肺组织免受颗粒侵害的肺细胞造成最大伤害。

Nanotechnology is the science that involves manipulating material and creating devices at the nanometre scale. These processes often produce nanoparticles and other nanostructures such as nanotubes and nanorods, with one or more dimensions of 100 nanometers or less, synthesised to have special characteristics for dedicated applications. Nanotechnology has been described as the next technological revolution, but has also prompted concerns about the potential of nanoparticles to harm humans or the biosphere. It is likely that the same factors responsible for the novel properties of nanoparticles may be the source of their potential hazard. Nanoparticle potency is due to their increasing reactivity as their size decreases, the result of an increase in the surface to bulk ratio, as particles become smaller. Hence nanoparticles generally have enhanced functionality but materials benign in bulk form may be hazardous at the nanoscale. Also, nanoscale particulate matter is simply more likely to be inhaled, ingested or absorbed and risks from accidental exposure are heightened. Nanoparticles are currently employed in over 200 commercial products including sunblocks, creams, cosmetics, fabric coatings, electronics, biocides and drug delivery systems and are inevitably entering the environment, either through manufacturing discharge, accidental spillage, or use. The environmental behaviour of engineered nanoparticles is currently unknown and their potential to harm human health is a major concern. In this proof-of-concept project, we propose to initiate an investigation of the behaviour of nanoparticles, following inhalation and possible transition into the blood stream, by investigating the reactivity of two types of engineered nanomaterials of broad current use and future application potential: multiwall carbon nanotubes and titania nanoparticles, with synthetic lung lining liquid and blood plasma. We will test how their physical properties, size, shape and structure, affect their behaviour in solution, specifically their solubility, surface area, surface charge, surface roughness and tendency for agglomeration, in two types of media, aiming to simulate blood plasma (simulated body fluid) and lung lining liquid (simulated lung secretions). Following completion of this work, the most and least reactive particles will be tested with primary human lung cells and cell lines to acquire proof-of-concept information as to whether the most reactive particles also tend to cause most harm to lung cells involved in the general defence of lung tissue against particulates.