据报道在我们2020年2月5,blog item中,American Conference of Governmental Industrial Hygienists (ACGIH®)阈限值化学物质(TLV®-CS)委员会列入2020年的化学物质,并正在研究其他问题清单上的碳纳米管。被放置在所研究列表上显示的TLV®-CS委员会选定的碳纳米管的阈限值的发展(TLV®)。ACGIH®现在已经发布了其two-tier under study list。Tier 1 lists the chemical substances and physical agents that may move forward as a notice of intended change (NIC) or notice of intent to establish (NIE) in the upcoming year, based on their status in the development process. Tier 2 consists of those chemical substances and physical agents that will not move forward, but will either remain on or be removed from the under study list for the next year. Carbon nanotubes are included in Tier 2. If carbon nanotubes are included on the2021under study list, stakeholders will have an opportunity to submit substantive data and comments.