Nanoprospecting: An Approach Towards Environmental Monitoring of Engineered Nanomaterials

CBET-1336542工程纳米材料(NMS)是一类新的污染物，关于它们对环境的潜在危害的争论越来越多。这项提议的目的是帮助获得关于危险评估暴露部分的更好信息。即使对于当今社会使用的高生产量NMS(二氧化钛和二氧化硅)，关于它们在水生系统中的浓度或出现频率的现场监测数据也很少。对即将广泛使用的NMS(如Ag0、CeO2、CNT、C60等)进行环境监测或者，除非存在框架和分析方法来了解在哪里以及如何找到NMS，否则未来式的高附加值NMS将是不可能实现的。我们建议开发和应用一个框架来监测环境中的NMS。纳米勘探是这一调查框架的第一阶段，涉及在城市供水系统的关键输入和沿线地点监测HPV的存在和新出现的NMS。散装食品配料是NMS进入城市供水系统的主要潜在来源。为了补充目前现有的分析方法在环境相关浓度下检测NMS的使用，我们建议改进来自特定仪器的数据信号的后处理，并通过利用NMS在溶剂-水或水-固界面上存在最小自由能的独特现象，发现几种利用NMS独特性质的NM提取技术的适用性。通过对当今环境中的几个NMS进行监控，可以收集信息和数据，并将其用于验证生命周期模型。研究围绕以下四个研究部分进行：(1)跨越城市水梯度的纳米勘探；(2)食品供应系统中的纳米勘探；(3)使用接口从水中提取纳米材料；(4)水生系统纳米材料的长期监测框架。具体地说，该项目将向科学界提供“真实”纳米材料的真实人类(通过食物)和生态系统(通过城市水梯度)暴露水平和特性的估计，而不是仅为研究级测试而购买或合成的纳米材料。将开发新的分析响应数据的提取方法和信号处理。这项研究的动机是以下科学问题：在城市水梯度上检测到纳米材料的频率是多少？散装食品配料和成品中纳米二氧化钛和二氧化硅的赋存状态和特征是什么？如何利用纳米物体吸附在液体或固体界面上的独特性质来从水中提取纳米材料并促进其表征？能否建立一个监测框架和监测站网络，以提供有关水中纳米材料的基线和长期数据？更广泛的影响：通过专注于现场范围的监测，我们希望引导环境纳米技术领域建立适用于监测与环境相关的NMS浓度的协议。研究人员已经证明，他们致力于指导不同性别和种族的本科生和研究生。该项目资助的研究生将参加在华盛顿特区举行的为期两周的沉浸式研讨会《实验室之外的科学》，该研讨会旨在探索科学如何成为政策。该项目与美国国家科学基金会中部-亚利桑那州长期生态研究(CAP-LTER)计划相联系，采用类似的纵向方法研究城市水梯度上的NMS，该项目收集的实地数据将成为CAP-LTER数据档案的一部分。该研究团队有向公众提供感兴趣和可见的研究的记录，并将继续努力与公众分享我们的成果，包括与亚利桑那州立大学社会纳米技术中心的合作。

CBET - 1336542 Engineered nanomaterials (NMs) are a new class of pollutants, and debate is growing regarding their potential hazard in the environment. This proposal aims to contribute towards gaining improved information on the exposure component of hazard assessment. Even for the high production volume (HPV) NMs used today in society (TiO2 and SiO2) there is a paucity of field monitoring data on their concentration or frequency of occurrence in aquatic systems. Environmental monitoring of NMs on the cusp of widespread use (e.g., Ag0, CeO2, CNT, C60, etc.) or futuristic high value-added NMs will remain unattainable unless frameworks and analytical methods exist to understand where and how to find NMs. We propose developing and applying a framework for monitoring NMs in the environment. Nanoprospecting is the first stage of this investigative framework, involving monitoring for the presence of HPV and emerging NMs at critical inputs to and points along the urban water system. Bulk food ingredients are a major potential source of NMs into the urban water system. To compliment the use of existing analytical approaches available today to detect NMs at environmentally relevant concentrations, we propose improvements to post-processing of data signals from specific instrumentation and discovering the suitability of several NM extraction techniques that leverage a unique property of NMs by exploiting the unique phenomena of NMs that a minimum free energy exists for NMs at the solvent-water or water-solid interface. By monitoring for a few NMs in the environment today, information and data can be collected and used in validating life cycle models. Research is organized around the following four research components: (1) Nanoprospecting across an urban water gradient; (2) Nanoprospecting in the food supply system; (3) Using interfaces for nanomaterial extraction from water; (4) Framework for long-term monitoring of aquatic systems for nanomaterials.Intellectual Merit :Nanoprospecting builds upon experiences of the environmental community dealing with other emerging contaminants and technologic shifts, and is complimentary to life cycle perspectives. Specifically, this project will provide the scientific community with estimates of realistic human (through food) and ecosystem (through urban water gradients) exposure levels and characteristics of "real" nanomaterials, as opposed to NMs purchased or synthesized solely for research-grade testing. New extraction methodologies and signal processing of analytical response data will be developed. The research is motivated by the following scientific questions: What is the frequency in detection of nanomaterials across the urban water gradient? What are the occurrences and characteristics of nanoscale TiO2 and SiO2 in bulk food ingredients and finished food products? How can the unique property that nanoscale objects adsorb at liquid or solid interfaces be harnessed to extract nanomaterials from water and facilitate their characterization? Could a monitoring framework and network of monitoring stations be established to provide baseline and longer-term data on nanomaterials in water? Broader Impacts :By focusing on field-scale monitoring we hope to lead the environmental nanotechnology field toward establishing protocols suitable for monitoring NMs at environmentally relevant concentrations. The researchers have a proven commitment to mentoring gender and ethnically iverse undergraduate and graduate students. The graduate student funded by this project will participate in Science Outside the Lab, a two-week immersive seminar in Washington, DC that explore how science becomes policy. The project connects with the NSF Central-Arizona hoenix Long Term Ecological Research (CAP-LTER) program, taking a similar longitudinal approach looking at NMs along the urban water gradient, and field data collected by this project will become part of the CAP-LTER data archives. The research team has a record of onducting research of interest and visible to the public, and will continue to strive to share our results with the public, including working with the Center for Nanotechnology in Society at ASU.