title: Symptoms from masked acrolein exposure suggest altered trigeminal reactivity in chemical intolerance.
abstract: BACKGROUND
  Chemical intolerance (CI) is a widespread occupational and public health problem characterized by symptoms that reportedly result from low-levels of chemical exposure. The mechanisms behind CI are unknown, however modifications of the chemical senses (rather than toxic processes) have been suggested as key components. The aim of this study was to investigate whether individuals with self-reported CI report more sensory irritation during masked acrolein exposure compared to controls without CI.
  
  
  METHODS
  Individuals with CI (n=18) and controls without CI (n=19) were exposed in an exposure chamber. Each participant took part in two exposure conditions - one with heptane (the masking compound), and one with heptane and acrolein at a dose below previously reported sensory irritation thresholds. The exposures lasted for 60min. Symptoms and confidence ratings were measured continuously throughout the exposure as were measurements of electrodermal activity and self-reported tear-film break-up time. Participants were blind to exposure condition.
  
  
  RESULTS
  Individuals with CI, compared with controls reported greater sensory irritation in the eyes, nose and throat when exposed to acrolein masked with heptane. There was no difference during exposure to heptane.
  
  
  CONCLUSIONS
  Masked exposure to acrolein at a concentration below the previously reported detection threshold is perceived as more irritating by individuals with CI compared with controls. The results indicate that there is altered trigeminal reactivity in those with CI compared to controls.
authors.affiliation: Department of Psychology, Umeå University, Umeå, Sweden. Electronic address: Anna-Sara.Claeson@umu.se.
authors.forename: Anna-Sara
authors.initials: AS
authors.lastname: Claeson
authors.affiliation: Department of Psychology, Umeå University, Umeå, Sweden.
authors.forename: Linus
authors.initials: L
authors.lastname: Andersson
mesh_terms: D000171:Acrolein / Q000633:toxicity*; D000328:Adult; D005260:Female; D005712:Galvanic Skin Response; D006801:Humans; D019570:Inhalation Exposure; D007509:Irritants / Q000633:toxicity; D008297:Male; D008875:Middle Aged; D012684:Sensory Thresholds / Q000187:drug effects*; D000074025:TRPA1 Cation Channel / Q000819:agonists*; D012668:Trigeminal Ganglion / Q000187:drug effects
chemical_list: D007509:Irritants; D000074025:TRPA1 Cation Channel; C473350:TRPA1 protein, human; D000171:Acrolein
keywords: Acrolein; Chemical intolerance; Human exposure; TRPA1; Trigeminal reactivity