EMPA, Swiss Federal Laboratories for Materials Science and Technology, Technology and Society Laboratory, Lerchenfeldstrasse 5, CH-9014, St. Gallen, Switzerland.
EMPA, Swiss Federal Laboratories for Materials Science and Technology, Technology and Society Laboratory, Lerchenfeldstrasse 5, CH-9014, St. Gallen, Switzerland.
Environ Pollut. 2018 Dec;243(Pt A):17-27. doi: 10.1016/j.envpol.2018.07.108. Epub 2018 Jul 24.
Most existing models for assessing the releases of engineered nanomaterials (ENMs) into the environment are based on the assumption that ENMs remain in their pristine forms during their whole life cycle. It is known, however, that this is not always the case as ENMs are often embedded into solid matrices during manufacturing and can undergo physical or chemical transformations during their life cycle, e.g. upon release to wastewater. In this work, we present a method for systematically assessing the forms in which nano-Ag and nano-TiO flow through their life cycle (i.e. production, manufacturing, use and disposal) to their points of release to air, soil and surface water. Input data on the forms of released ENMs were probability distributions based on peer-reviewed literature. Release data were incorporated into a probabilistic material flow analysis model to quantify the proportions of ENMs in product-embedded, matrix-embedded, pristine, transformed and dissolved forms in all technical and environmental compartments into which they flow, at the European scale. Releases of nano-Ag to surface water and soil were modelled to occur primarily in transformed forms (Q25 and Q75 of 34-58% and 78-86%, respectively, with means of 53% and 82%), while releases to air were mostly in pristine and matrix-embedded forms (38-46% and 36-44%, respectively, with means of 42% and 40%). In contrast, nano-TiO releases to air, soil and water were estimated to be predominantly in pristine form (75-85%, 90-95%, 96-98%, respectively, with means of 80%, 91% and 97%). The distributions of ENM releases between forms developed here will improve the representativeness and appropriateness of input data for environmental fate modelling and risk assessment of ENMs.
大多数现有的评估工程纳米材料（ENMs）释放到环境中的模型都基于这样一种假设，即 ENMs 在其整个生命周期中都保持其原始形态。然而，众所周知，情况并非总是如此，因为 ENMs 在制造过程中通常嵌入到固体基质中，并且在其生命周期中可能会经历物理或化学转化，例如在释放到废水中时。在这项工作中，我们提出了一种方法，用于系统地评估纳米银和纳米二氧化钛在其生命周期（即生产、制造、使用和处置）中通过其生命周期的形式，以及它们释放到空气、土壤和地表水的释放点。关于释放的 ENMs 形式的输入数据是基于同行评议文献的概率分布。释放数据被纳入概率物质流分析模型中，以量化它们在所有技术和环境隔室中以产品嵌入、基质嵌入、原始、转化和溶解形式存在的比例，在欧洲范围内。模拟纳米银释放到地表水和土壤中主要以转化形式发生（Q25 和 Q75 分别为 34-58%和 78-86%，平均值分别为 53%和 82%），而释放到空气中的主要以原始和基质嵌入形式存在（Q25 和 Q75 分别为 38-46%和 36-44%，平均值分别为 42%和 40%）。相比之下，纳米二氧化钛释放到空气、土壤和水中估计主要以原始形式存在（分别为 75-85%、90-95%、96-98%，平均值分别为 80%、91%和 97%）。这里开发的 ENM 释放形式之间的分布将提高输入数据的代表性和适当性，以进行环境归宿建模和 ENM 的风险评估。
