title: Exposure study to examine chemosensory effects of ɛ-caprolactam in healthy men and women.
abstract: ε-Caprolactam is an important industrial chemical with a relatively low human toxicity; of importance is the irritations that occur after exposure to ε-caprolactam as aerosols or vapors.
  
  
  
  The aim of this study was to examine symptoms and objective effects, which occur on the mucous membranes of the eyes and the upper respiratory tract.
  
  
  
  A total of 52 healthy volunteers (26 women and 26 men, aged between 19 and 50 years) were exposed by random to different ε-caprolactam concentrations (0.05, 0.5 and 5.0 mg/m³) and the control condition (0.0 mg/m³) for 6 h on four consecutive days. Eye blinking frequency, tear film break-up time, eye redness, nasal flows and resistance, olfactory function as well as total protein and interleukin-8 in nasal lavage fluid were determined daily before, during and after exposure. Questionnaires were used to record both subjective symptoms and personality factors.
  
  
  
  There were no significant specific effects on the subjective and objective endpoints examined. Statistical analysis yielded no evidence of concentration-response relationships. Evaluation of olfactory symptoms showed that the duration of the stay in the chamber and not the ε-caprolactam concentration was decisive for the perception of "impure air". Personality factors had no significant influence on the reported symptoms.
  
  
  
  Exposure to ε-caprolactam concentrations of 5.0 mg/m³ at maximum for 6 h did not cause chemosensory effects on the upper respiratory tract or eyes of healthy volunteers. Therefore, the concentration of 5.0 mg/m³ corresponds to the No Observed Adverse Effect Level (NOAEL).
authors.affiliation: a Occupational and Social Medicine, University Hospital Heidelberg , Heidelberg , Germany , and.
authors.forename: Gerhard
authors.initials: G
authors.lastname: Triebig
authors.affiliation: a Occupational and Social Medicine, University Hospital Heidelberg , Heidelberg , Germany , and.
authors.forename: Isabel
authors.initials: I
authors.lastname: Triebig-Heller
authors.affiliation: b Institute of Medical Biometry and Informatics, University Hospital Heidelberg , Heidelberg , Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Bruckner
mesh_terms: D000280:Administration, Inhalation; D000328:Adult; D002209:Caprolactam / Q000032:analysis / Q000633:toxicity*; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005123:Eye / Q000187:drug effects*; D005260:Female; D006801:Humans; D016209:Interleukin-8 / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009092:Mucous Membrane / Q000187:drug effects*; D017817:Nasal Lavage Fluid / Q000737:chemistry; D019055:No-Observed-Adverse-Effect Level; D012137:Respiratory System / Q000187:drug effects*; D012903:Smell / Q000187:drug effects; D055815:Young Adult
chemical_list: C508606:CXCL8 protein, human; D016209:Interleukin-8; D002209:Caprolactam
keywords: Caprolactam; chemosensory effects; exposure study; eye blinking frequency