This study was carried out in a factory producing multiwalled carbon nanotubes (MWCNTs) by the catalytic chemical vapor deposition method in a pyrolysis reactor. Air samples of the personal breathing areas were collected simultaneously on mixed cellulose ester filters, for analysis by transmission electron s (TEM), and on high-purity quartz filters for thermal-optical analysis of elemental carbon (EC). It is found that the production of MWCNTs is accompanied by the release of the MWCNT structures in the air of different working zones. The concentration of respirable aerosol in the personal breathing areas, averaged over an 8-hour period, ranges from 0.54 to 6.11 μg/m³ based on EC. Airborne MWCNTs were found in the form of agglomerates that range in size from about 1 to 10 μm. These data are consistent with measurements in different plants by two other international groups (from the United States and Sweden) using similar methodology (TEM in combination with EC analysis). In the absence of convincing data on the potential health risks of MWCNTs, and following the principle of reasonable precautions, preventive measures should be taken to minimize exposure to these materials.

中文翻译：

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在制造环境中评估机载多壁碳纳米管。

这项研究是在热解反应器中通过催化化学气相沉积法在生产多壁碳纳米管（MWCNT）的工厂中进行的。同时在混合纤维素酯过滤器上收集个人呼吸区域的空气样本，以通过透射电子（TEM）进行分析；在高纯度石英过滤器上，用于元素碳的热光分析（EC）。已经发现，MWCNT的生产伴随着MWCNT结构在不同工作区域的空气中的释放。在8小时内，个人呼吸区域中可吸入气溶胶的浓度平均为0.54至6.11μg/ m ^3。基于EC。发现机载的MWCNT以附聚物形式存在，其大小范围为约1至10μm。这些数据与另外两个国际集团（来自美国和瑞典）使用类似方法（TEM结合EC分析）在不同工厂进行的测量结果一致。在没有令人信服的关于多壁碳纳米管潜在健康风险的数据的情况下，并遵循合理预防措施的原则，应采取预防措施以尽量减少接触这些材料。