====== Carbon Nanotubes ====== **Or, "Carbon Nano Tubes (CNTs) and Carbon Nano Fibers (CNF's) and the Health Risks from their use in ESD-Safe Filaments"** ==== What and Where are Carbon Nanotubes? ==== Carbon Nano Tubes are found in ESD-Safe filaments from various companies such as 3DXTECH or Polymaker. Despite being available to the general public, significant health risks are posed by CNTs to people's health if they are exposed to the fibres. CNT and Carbon Nano Fibers (CNFs) are completely different to Carbon Fibre! These are of a much smaller size than Carbon Fiber and the health risks reflect this! ==== What are the Risks? ==== Based on a significant amount of evidence collected by the CDC since 2013 and other research papers(([[https://link.springer.com/article/10.1007/s11051-020-4750-8|Three-dimensional printer emissions and employee exposures to ultrafine particles during the printing of thermoplastic filaments containing carbon nanotubes or carbon nanofibers]])) show that CNT and CNF are released during 3D printing. In 2013 the CDC released Current Intelligence Bulletin 65(([[https://www.cdc.gov/niosh/docs/2013-145/pdfs/2013-145.pdf|CDC Current Intelligence Bulletin 65 - Occupational Exposure to Carbon Nanotubes and Nanofibers]])) going into great detail about what Carbon Nano Tubes are, the research and information about the health risks that they pose and that exposure to them in a workplace should be below 1 ug/m3 in a 8 hour Time Weighted Average (TWA), specifically stating: **"...all types of CNT and CNF should be considered a respiratory hazard and exposure should be controlled below the REL."** For context, the following is a list of high risk chemicals for the same TWA period: ^ Substance ^ TWA (ug/m³) ^ |Hydrogen Cyanide |10,800 | |Benzene |1,600 | |Lead |50 | |Quartz (Silica) |25 | |Arsenic |10 | |Carbon Nano Tubes (CNTs) |**1** | ==== What this Means to You ==== A TWA of 1ug/m3 for CNT's by comparison to something like Arsenic at 10ug/m3, reflects how serious the CDC considers the risk they pose. For you reading this, ask yourself: "Do you want to be exposed to something with a higher risk to your health then Lead, Benzene or Quartz silica dust? The same types of dust that cause silicosis, lung cancer and other respiratory diseases? Much less be exposed to such a material without your knowledge?" The type, level and detail of control measures listed by the CDC in relation to CNF to limit and track exposure to such a high risk material is well outside the average consumer to implement and factor in when handling, printing or post processing 3d printer filaments and parts with this material in it. This is further compounded by a systemic lack of any detailed information provided about the health risks of CNT in the 3D printing space and the recent discussions raised around Carbon Fibre in filaments which are not even close to CNT and CNF in the health risks they pose. It is 2024 2025, the risks of CNT have been known about since 2013, and the most recent technical report 2022-153 from the CDC(([[https://www.cdc.gov/niosh/docs/2022-153/2022-153.pdf?id=10.26616/NIOSHPUB2022153|CDC Technical Report - Occupational Exposure Sampling for Engineered NanoMaterials]])) continues to echo the same limit of 1ug/m3, echoing: "Occupational exposure to CNTs and CNFs is associated with biomarkers of early effect for fibrosis, inflammation, oxidative stress, and cardiovascular responses in workers [Beard et al. 2018]." **Please, if you value your health and the health of others inside this space please share and spread the information and help to keep people safe from serious life impacting health issues while enjoying a hobby.** ==== Takeaway ==== CNT and CNF filled parts are on the same level of heath risk as asbestos fibre products. Just like asbestos fibres, parts produced with CNT/CNF fill will always be a ticking time bomb of fibres being released during the life of a product containing them in addition to the fibres released during printing.