The Effect of M-Xylene on Cytotoxicity and Cellular Antioxidant Status in Rat Dermal Equivalents

Details

• Personal Author:
  Coleman CA ; Hull BE ; McDougal JN ; Rogers JV
• Description:
  Exposure of the skin to volatile organic chemicals (VOCs) can lead to irritation, inflammation and cytotoxicity. Since VOCs are used in industrial, commercial and military applications, concern is mounting with respect to VOC safe exposure limits. Although traditional toxicological assessment of VOCs has utilized animal models, the use of alternative in vitro models is becoming more widespread. We have previously developed a sealed exposure system that prevents chemical loss through evaporation and enables calculation of target cell chemical dose. The present study utilized this in vitro exposure method to assess m-xylene-induced cytotoxicity and antioxidant status in dermal equivalents (dermal fibroblasts in a collagen matrix). At the end of a 1- or 4-h exposure, cytotoxicity was measured using the MTT assay and the EC50 values determined were 1481 +/- 88 and 930 +/- 33, respectively. Decreases in cellular thiols and catalase activity were observed, which occurred in a time and dose-dependent manner. Treatment of dermal equivalents with the antioxidants N-acetylcysteine (NAC) and catalase provided some protection against m-xylene-induced cytotoxicity. When compared to m-xylene exposures, treatment with either 1.0 or 5.0 mM NAC led to increases in the EC50 values at 1 and 4 h. Increases in these EC50 values ranged from 1.22- to 1.32-fold at 1 h and 1.27- to 1.54-fold at 4 h. Although treatment with catalase (1000 U/ml) led to a 1.35-fold increase in cell viability at 1 h, no significant differences were observed at either 1 or 4 h when compared to dermal equivalents exposed to m-xylene alone. These results suggest that exposure to m-xylene leads to a time- and dose-dependent decrease in cellular antioxidants and that cellular thiols may provide protection against the cytotoxic properties of m-xylene. [Description provided by NIOSH]
• Subjects:
  Antioxidants Cytotoxins Environmental Monitoring Occupational Health Safety Skin Xylenes
• Keywords:
  Antioxidation Cytotoxic-effects Cytotoxicity Exposure-assessment Exposure-levels Exposure-limits In-vitro-studies In-vitro-study Organic-chemicals Skin-exposure Skin-irritants

  More +
• ISSN:
  0378-4274
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  Ohio ; OSHA Region 5
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  133-142
• Volume:
  142
• Issue:
  1
• NIOSHTIC Number:
  nn:20029158
• Citation:
  Toxicol Lett 2003 Apr; 142(1-2):133-142
• Contact Point Address:
  ManTech, 2856 G Street, Building 79, Wright-Patterson AFB, OH 45433, USA
• Email:
  james.rogers@wpafb.af.mil
• Federal Fiscal Year:
  2003
• Peer Reviewed:
  True
• Source Full Name:
  Toxicology Letters
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:ec7889ff69dd72d2de41e8023cc15027600c1700f9056faea454a53cab4d7783e5f15ca142583483324e538d31e58d059ddb808c95db0fa7dd5cf75206f30449
• Download URL:
  https://stacks.cdc.gov/view/cdc/190210/cdc_190210_DS1.pdf
• File Type:
  [PDF - 166.62 KB ]