Occupational ototoxicity of n-hexane

Hum Exp Toxicol. 2008 Jun;27(6):471-6. doi: 10.1177/0960327108093719.

Abstract

The ability of chemicals to produce hearing loss themselves or to promote noise-induced hearing loss has been reported for some organic solvents. The objective of this study was to review the literature on the effects of low-level exposure to n-hexane on the auditory system and consider its relevance for occupational settings. Both human and animal investigations were evaluated only for realistic exposure concentrations based on the permissible inhalation exposure limits. In Quebec, the time-weighted average exposure value (TWAEV) for 8 h is 50 ppm. In humans, the upper limit for considering ototoxicity data relevant to the occupational exposure situation was set at five times the TWAEV. Animal data were evaluated only for exposure concentrations up to 100 times the TWAEV. There is no convincing evidence of n-hexane-induced hearing loss in workers. In rats, n-hexane seems to affect auditory function; however, the site of these alterations cannot be determined from the present data. Further studies with sufficient data on the exposure of workers to n-hexane are necessary to make a definitive conclusion. In the interim, we recommend considering n-hexane as a possibly ototoxic agent.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Adhesives / adverse effects*
  • Air Pollutants, Occupational / adverse effects*
  • Animals
  • Evoked Potentials, Auditory / drug effects
  • Hearing Loss / etiology*
  • Hearing Loss / physiopathology
  • Hexanes / adverse effects*
  • Humans
  • Inhalation Exposure
  • Noise / adverse effects
  • Occupational Diseases / etiology*
  • Occupational Diseases / physiopathology
  • Occupational Exposure / adverse effects*
  • Threshold Limit Values

Substances

  • Adhesives
  • Air Pollutants, Occupational
  • Hexanes
  • n-hexane