Olfactory function in workers exposed to styrene in the reinforced-plastics industry.
BACKGROUND
Impairment of olfactory function in humans has been associated with occupational exposure to volatile chemicals. To investigate whether exposure to styrene was associated with olfactory impairment, olfactory function was examined in workers with a minimum of 4 years exposure to styrene in the reinforced-plastics industry (current mean exposure: 26 ppm, range: 10-60 ppm; historic mean dose: 156 ppm-years, range: 13.8-328 ppm-years) and in a group of age- and gender-matched, unexposed controls.


METHODS
Olfactory function was assessed using a standardized battery that included tests of threshold sensitivity for phenylethyl alcohol (PEA), odor identification ability, and retronasal odor perception. Odor detection thresholds for styrene were also obtained as a measure of specific adaptation to the work environment.


RESULTS
No differences were observed between exposed workers and controls on tests of olfactory function. Elevation of styrene odor detection thresholds among exposed workers indicated exposure-induced adaptation.


CONCLUSIONS
The present study found no evidence among a cross-section of reinforced-plastics industry workers that current or historical exposure to styrene was associated with impairment of olfactory function. Taken together with anatomical differences between rodent and human airways and the lack of evidence for styrene metabolism in human nasal tissue, the results strongly suggest that at these concentrations, styrene is not an olfactory toxicant in humans.
Dalton
Pamela
P
Monell Chemical Senses Center, Philadelphia, Pennsylvania 19104-3308, USA. pdalton@pobox.upenn.edu
Cowart
Beverly
B
Dilks
Daniel
D
Gould
Michele
M
Lees
Peter S J
PS
Stefaniak
Aleksandr
A
Emmett
Edward
E
D000222:Adaptation, Physiological; D000328:Adult; D000367:Age Factors; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D004202:Disinfectants / Q000032:analysis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016273:Occupational Exposure / Q000032:analysis*; D009812:Odorants / Q000032:analysis*; D010626:Phenylethyl Alcohol / Q000032:analysis; D010969:Plastics; D012684:Sensory Thresholds / Q000502:physiology*; D012903:Smell / Q000502:physiology*; D020058:Styrene / Q000032:analysis*; D013997:Time Factors; D014481:United States
D004202:Disinfectants; D010969:Plastics; D020058:Styrene; D010626:Phenylethyl Alcohol