Tracking relevant nanomaterial transformations, exposure, uptake and effects in freshwater and soil systems

纳米材料（NM）是非常小的颗粒，比人类头发的宽度小得多。它们被合成以提供来自相同材料的更大形式的不同特性，它们现在被用于广泛的产品中。纳米材料提供的特性包括增强的强度、反射光或与其他化学物质反应的能力以及有效的导电性。NM的价值现在得到了广泛的认可，许多公司开始将其用于普通消费品，如防晒霜和化妆品，以及工业产品，如织物和建筑材料。这意味着少量的NM将从日常产品使用中进入更广泛的环境。最近的大量研究已经进入评估NM对人类和环境的安全性。这些研究中的大多数都着眼于新制造的纳米材料。然而，越来越明显的是，一旦纳米材料被释放到更广泛的环境中，它们就不会停留在制造状态--它们会发生变化或“转化”。转化可以影响纳米的大小，电荷，它们的表面涂层以及它们与其他物质如土壤颗粒或其他化学物质结合的能力。转化发生在向环境转移的过程中（例如通过污水处理厂），也发生在纳米物质进入更广泛的环境（河流、沉积物和土壤）之后。我们了解纳米物质的转化过程和环境命运非常重要，因为它们会影响它们对人类和环境的毒性。本项目的目的是更详细地研究这些NM转换。我们希望更好地了解不同类型的NM是否以相同或不同的方式进行转换。我们将使用不同类型的纳米材料进行研究，包括由银、二氧化钛、聚苯乙烯（一种塑料）和石墨烯（一种碳）制成的纳米材料。我们将首先使用实验室方法，模拟在污水处理过程中以及在自然沃茨和土壤中纳米材料的变化方式，以创造我们将研究的转化材料。我们将测试这些新的和变化的纳米物质如何影响一系列常见的水生和土壤生物，并将它们在“原始”状态下的毒性与它们在环境中转化不同时间后的毒性进行对比。在我们的测试中，我们将测量生物体在不同组织中吸收了多少每种物质，以及这是否会影响它们的生长和繁殖。我们还将测量不同基因的活性，这些基因可能会受到生物体吸收不同NM的影响。我们预测，每一个纳米都将以一种改变其造成有害影响的可能性的方式进行转变。每个测试将使用英国各地常见的不同土壤和沃茨进行重复，以确定在不同条件下转化的变化。最后，我们将建立定制的大型暴露系统（“中型生态系统”），旨在模拟污水厂排放的河流和污泥散布的土壤，并在其中种植各种常见的英国本土植物，无脊椎动物和鱼类（在沃茨中）。通过跟踪这些中型生态系统几个月，我们可以模拟在真实的英国环境中可能实际发生的事情，即我们转变的NM的命运和影响。我们将使用这些结果来改进模型，这些模型能够预测我们转换后的NM将如何表现以及它们将产生的影响。总之，我们的研究结果应该有助于我们预测纳米材料的毒性，以帮助确保其安全性，支持纳米技术行业未来的发展。为此，我们将运行和协调英国纳米学者和监管机构平台，并将通过主要的欧盟（纳米安全集群）和全球（经济合作与讨论组织）政策工作组以及公众展示我们的成果，从而达到尽可能广泛的受众。

Nanomaterials (NM) are very small particles much less than the width of a human hair. They are synthesised to provide different properties from larger forms of the same material and they are now used in a wide range of products. The properties that NMs provide include enhanced strength, an ability to reflect light or to react with other chemicals, and efficient electrical conductance. The value of NM is now very widely recognised and many companies are starting to use them in common consumer products, such as sunscreens and cosmetics, plus industry products, such as fabrics and building materials. This means that small quantities of NMs will reach the wider environment from everyday product use.A great deal of recent research has gone into assessing the safety of NMs for humans and the environment. Most of these studies have looked at NMs in their newly-manufactured forms. It is increasingly apparent, however, that once NMs are released into the wider environment, they do not stay in their manufactured state - they change or 'transform'. Transformations can affect NM size, charge, their surface coatings and their ability to bind to other things such as soil particles or other chemicals. Transformations occur both during transfer to the environment (e.g. via sewage works) and once NMs reach the wider environment itself (rivers, sediments and soils). It is of huge importance that we understand the transformation processes and environmental fate(s) of NMs as they can affect their toxicity to humans and the environment. The aim of this project is to study these NM transformations in more detail. We want to better understand whether different types of NMs are transformed in the same or different ways. We will conduct our work with different types of NMs, including those made from silver, titanium dioxide, polystyrene (a type of plastic) and graphene (a type of carbon). We will first use laboratory methods that mimic the ways that NMs are changed during sewage treatment and in natural waters and soils to create the transformed materials that we will then study. We will test how these new and changed NMs affect a range of common aquatic and soil organisms and contrasting their toxicity in their "pristine" state with that after they have been transformed in the environment for different times. During our tests, we will measure how much of each material is taken up by the organisms into different tissues and whether this affects how they grow and reproduce. We will also measure the activity of different genes that are likely to be affected as organisms take up different NMs. We predict that each NM will be transformed in a way that changes its likelihood to cause harmful effects. Each test will be repeated using different soils and waters typically found across the UK, to determine how transformations vary under different conditions.Finally, we will build custom-made, large exposure systems ('mesocosms') designed to mimic the rivers into which sewage works discharged and soils upon which sludge is spread, and populate them with a wide range of common UK native plants, invertebrates and fish (in the waters). By following these mesocosms for several months, we can simulate what may actually be happening in real UK environments in terms of the fate and effects of our transformed NMs. We will use the results to improve models able to predict how our transformed NMs will behave and the effects they will have. Taken together, our results should help us to predict the toxicity of NMs to help assure their safety, supporting the growth of the nanotechnology industry into the future. To this latter end we will run and coordinate a UK Nano-Academics & Regulators Platform, and will also present our results through major European Union (NanoSafety Cluster) and worldwide (Organisation for Economic Cooperation and Discussion) policy working groups, as well as to the public, so reaching as wide an audience as possible.