TOBACCO-SMOKE UPPER RESPIRATORY RESPONSE RELATIONSHIPS IN HEALTHY NONSMOKERS

This study determined exposure-response relationships to sidestream to bacco smoke (2 hrs; 0, 1, 5, and 15 ppm CO) in 29 healthy nonsmoking y oung adults, Sixteen subjects had no history of environmental tobacco smoke rhinitis (ETS-NS) while 13 subjects had a history of ETS rhiniti s (ETS-S), Eye irritation and odor perception showed a statistically s ignificant exposure response in both groups; headache was significant in ETS-S and nose irritation was significant in ETS-NS subjects. Signi ficant postexposure (P1) symptoms were first reported at 1 ppm CO amon g both groups, but in 3/9 symptoms were significantly greater at this exposure level in ETS-S subjects, Nasal congestion, rhinorrhea, and co ugh increased significantly at 15 ppm CO only, In ETS-S subjects, nasa l volume decreased and nasal resistance increased in an exposure-respo nse fashion, ETS-NS subjects had a qualitatively different shape to th e exposure-response curve; significant dimensional reductions in mid- and posterior nasal volume occurred with exposure at 1 ppm CO but not at 5 ppm CO and reductions in posterior nasal volume occurred at 15 pp m CO exposure, These studies indicate subjective and objective respons e relationships with exposure to sidestream tobacco smoke at concentra tions from 1 to 15 ppm CO, Some differences are noted among the two su bject groups in the magnitude of some symptoms at the lowest exposure level and in the qualitative shape of the acoustic rhinometry and nasa l resistance exposure-response curves. (C) 1996 Society of Toxicology