Bioactivity of Multiwalled Carbon Nanotube Mixtures with Multiple Aspect Ratios

Details

• Personal Author:
  Erdely A ; Eye T ; Hubczak J ; Kodali V ; Roberts J ; Shoeb M ; Smith K ; Stefaniak, Aleksandr B. ; Stueckle, Todd A.
• Description:
  Multi-walled carbon nanotube (MWCNT) composites have vastly superior mechanical and structural properties compared to conventional materials. In order to be cost effective and to improve the distribution in the composite matrix, MWCNTs produced in large volume with multi-aspect ratios are utilized. Past research identified pulmonary health effects and the molecular mechanisms associated with exposure to mostly uniformly dimensional tubes; however, much is unknown concerning exposure associated with mixtures containing multi-aspect ratio tubes. In order to investigate this concern, we evaluated the toxicity profile of two multi-aspect-ratio MWCNT mixtures (MWCNT-1 and MWCNT-2) and compared them with the toxicity profile of more uniform and well-characterized MWCNT (Mitsui-7) and carbon black (CB, Printex-90) samples. Automated field emission scanning electron microscopic analysis showed that the MWCNT mixtures had a wide distribution of lengths from a few nanometers up to 20 microm and diameters that change according to length. The Mitsui-7 were more uniform with a diameter approximately 50 nm and the CB had a diameter of approximately 20 nm. Cytotoxicity and cell proliferation was assessed in human monocytic cells (THP-1) at 0 - 120 microg/ml and in primary human fibroblast cells (PHF) at 0 - 16 microg/ml. NFkB (nuclear factor kappa-light-chain-enhancer of activated B cells)-induced inflammatory potential was screened using THP-1 reporter cells. THP-1 WT and NLRP3-deficient cells were used to screen for inflammasome activation. Acellular oxidative stress potential of the material correlated with the fold increase in in vitro NFkB activation and oxidative stress induction, measured using a dichlorofluorescin-diacetate assay. The extracellular remodeling and fibroblast transformation potential was evaluated by measuring collagen 1, alpha-smooth muscle actin, and TGF-B in PHF cells. Given the toxicity and the metrics for molecular initiating events, the MWCNT-2 mixture was the most bioactive material followed by Mitsui-7 > CB > MWCNT-1. We conclude that it was not possible to fit all multi-aspect-ratio MWCNTs into a universal toxicity profile. Ongoing extensive physiochemical characterization could elucidate the key confounders influencing the toxicity profiles of such a multi-aspect-ratio MWCNT mixture. [Description provided by NIOSH]
• Subjects:
  Biological Assay Cells, Cultured Chemistry Cytotoxins Environmental Exposure Hazardous Substances Laboratories Occupational Health Particulate Matter Safety Toxicology

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• Keywords:
  Bioactivation Bioassays Carbon Black Carbon Nanotubes Cell Cultures Cell Culture Techniques Cell Function Cell Proliferation Cell Transformation Cellular Effects Cellular Reactions Chemical Properties CNT Cytotoxicity Exposure Assessment Exposure Levels Fibroblasts Humans Laboratory Testing Molecular Signaling Multi-walled Carbon Nanotubes MWCNT Nanocomposites Nanotoxicology Nanotubes Oxidative Stress Particle Diameter Particle Size Physical Properties Proteins Scanning Electron Microscopy Toxic Materials Ultrafine Particles

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• ISSN:
  1096-6080
• Document Type:
  Text
• Genre:
  Abstract or Summary
• Place as Subject:
  Maryland ; OSHA Region 3 ; West Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  HELD - Health Effects Laboratory Division ; RHD - Respiratory Health Division
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  168
• Issue:
  1
• NIOSHTIC Number:
  nn:20055013
• Citation:
  Toxicologist 2019 Mar; 168(1):286
• CAS Registry Number:
  Carbon black (CAS RN 1333-86-4) ; Carbon nanotubes (CAS RN 308068-56-6)
• Federal Fiscal Year:
  2019
• NORA Priority Area:
  Construction ; Manufacturing
• Peer Reviewed:
  False
• Source Full Name:
  The Toxicologist. Society of Toxicology 58th Annual Meeting and ToxExpo, March 10-14, 2019, Baltimore, Maryland
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:bac34026cb41869d69ebbd756f2cf963d9b617b9c3084f6fe91b03b3fd01dc87422d915bd4bf1080806627e13ff0138cd59682686bf56d7ee0e6860519d7c69c
• Download URL:
  https://stacks.cdc.gov/view/cdc/217417/cdc_217417_DS1.pdf
• File Type:
  [PDF - 857.95 KB ]