Acute effects of exposure to vapors of 3-methyl-1-butanol in humans.

The secondary alcohol 3-methyl-1-butanol (3MB, isoamyl alcohol) is used, for example, as a solvent in a variety of applications and as a fragrance ingredient. It is also one of the microbial volatile organic compounds (MVOCs) found in indoor air. There are little data on acute effects. The aim of the study was to assess the acute effects of 3MB in humans. Thirty healthy volunteers (16 men and 14 women) were exposed in random order to 1 mg/m(3) 3MB or clean air for 2 h at controlled conditions. Ratings with visual analogue scales revealed slightly increased perceptions of eye irritation (P = 0.048, Wilcoxon) and smell (P < 0.0001) compared with control exposure. The other ratings were not significantly affected (irritation in nose and throat, dyspnea, headache, fatigue, dizziness, nausea, and intoxication). No significant exposure-related effects were found in blinking frequency, tear film break-up time, vital staining of the eye, nasal lavage biomarkers, lung function, and nasal swelling. In conclusion, this study suggests that 3MB is not a causative factor for health effects in damp and moldy buildings.

CONCLUSIONS

3-Methyl-1-butanol (3MB) is one of the most commonly reported MVOCs in damp and moldy buildings and in occupational settings related to agriculture and composting. Our study revealed no irritation effects at 1 mg/m3, a concentration higher than typically found in damp and moldy buildings. Our study thus suggests that 3MB is not a causative factor for health effects in damp and moldy buildings.