It is well established that printers emit nanoparticles during their operation. To-date, however, the physicochemical and toxicological characterization of "real world" printer-emitted nanoparticles (PEPs) remains incomplete, hampering proper risk assessment efforts. Here, we investigate our earlier hypothesis that engineered nanomaterials (ENMs) are used in toners and ENMs are released during printing (consumer use). Furthermore, we conduct a detailed physicochemical and morphological characterization of PEPs in support of ongoing toxicological assessment. A comprehensive suite of state of the art analytical methods and tools was employed for the physicochemical and morphological characterization of 11 toners widely utilized in printers from major printer manufacturers and their PEPs. We confirmed that a number of ENMs incorporated into toner formulations (e.g. silica, alumina, titania, iron oxide, zinc oxide, copper oxide, cerium oxide, carbon black among others) and released into the air during printing. All evaluated toners contained large amounts of organic carbon (OC, 42-89%), metals/metal oxides (1-33%), and some elemental carbon (EC, 0.33-12%). The PEPs possess a composition similar to that of toner and contained 50-90% OC, 0.001-0.5% EC and 1-3% metals. While the chemistry of the PEPs generally reflected that of their toners, considerable differences are documented indicative of potential transformations taking place during consumer use (printing). We conclude that: (i) Routine incorporation of ENMs in toners classifies them as nano-enabled products (NEPs); (ii) These ENMs become airborne during printing; (iii) The chemistry of PEPs is complex and it reflects that of the toner and paper. This work highlights the importance of understanding life-cycle (LC) nano-EHS implications of NEPs and assessing real world exposures and associated toxicological properties rather than focusing on "raw" materials used in the synthesis of an NEP.

中文翻译：

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消费者暴露于激光打印机发射的工程纳米颗粒：纳米产品对生命周期影响的案例研究。

众所周知，打印机在运行过程中会发出纳米颗粒。但是，迄今为止，“现实世界”打印机发出的纳米粒子（PEP）的物理化学和毒理学表征仍然不完整，这妨碍了适当的风险评估工作。在这里，我们研究了我们先前的假设，即在调色剂中使用了工程纳米材料（ENM），而在打印（消费者使用）过程中释放了ENM。此外，我们对PEP进行了详细的理化和形态表征，以支持正在进行的毒理学评估。一整套最先进的分析方法和工具用于对11种墨粉的物理化学和形态表征进行了表征，这些墨粉已被主要打印机制造商及其PEP广泛使用在打印机中。我们确认，许多ENM掺入墨粉配方中（例如二氧化硅，氧化铝，二氧化钛，氧化铁，氧化锌，氧化铜，氧化铈，炭黑等）并在打印过程中释放到空气中。所有评估的碳粉均含有大量有机碳（OC，42-89％），金属/金属氧化物（1-33％）和一些元素碳（EC，0.33-12％）。PEP具有类似于调色剂的组成，并包含50-90％的OC，0.001-0.5％的EC和1-3％的金属。虽然PEP的化学成分通常反映出其碳粉的化学成分，但有记录表明存在很大差异，表明在消费者使用（印刷）期间会发生潜在的转变。我们得出以下结论：（i）在色粉中常规掺入ENM会将其归类为纳米级产品（NEP）；（ii）这些ENM在打印过程中变为机载；（iii）PEP的化学成分很复杂，它反映了碳粉和纸张的化学成分。这项工作强调了了解NEP的生命周期（LC）纳米EHS含义和评估现实世界中的暴露及其相关毒理学特性的重要性，而不是着重于NEP合成中使用的“原始”材料。