title: Breath concentration as an index of the health risk from benzene. Studies on the accumulation and clearance of inhaled benzene.
abstract: Human subjects were exposed to known concentrations of benzene in air for single and repeated daily periods. The breath concentrations measured repeated exposures approached a maximum after 3 d, and this phenomenon indicated that the tissues were approaching saturation under the experimental conditions. The breath concentrations measured after exposure indicated an initial rapid clearance of benzene with a half-time of 2.6 h, followed by a slower phase with a half-time of 24 h. The decay in breath concentration after prolonged occupational exposure appeared to be slower; the difference between the laboratory and industrial studies was, however, not significant. The hygienic significance of these results was discussed, and it was recommended that control measures be employed when a morning breath concentration exceeds 10 ppb.
mesh_terms: D001273:Atmosphere Exposure Chambers; D001554:Benzene / Q000009:adverse effects / Q000032:analysis / Q000378:metabolism*; D001944:Breath Tests / Q000379:methods; D002849:Chromatography, Gas; D004780:Environment, Controlled; D004781:Environmental Exposure; D005260:Female; D006801:Humans; D008297:Male; D013058:Mass Spectrometry; D012306:Risk; D013997:Time Factors
chemical_list: D001554:Benzene