Acute effects of exposure to vapours of hydrogen peroxide in humans

Hydrogen peroxide is a reactive chemical mainly used for bleaching, as a disinfectant, and as a general oxidising agent. This study investigated subtle acute effects of inhaled hydrogen peroxide vapours. Eleven healthy volunteers were exposed to 0 (clean air), 0.5 and 2.2 ppm for 2 hours at rest. Symptoms related to irritation and central nervous system effects were rated with Visual Analogue Scales. The ratings varied considerably but were generally low and with no significant differences between exposure conditions, although the ratings of smell (Friedman’s test), nasal irritation and throat irritation showed borderline tendencies to increase at 2.2 but not at 0 and 0.5 ppm. Nasal airway resistance increased after exposure to 2.2 ppm hydrogen peroxide (paired t-test) but not after 0.5 ppm. No exposure-related effects on pulmonary function, nasal swelling, breathing frequency and blinking frequency were detected. Furthermore, no clear effects were seen on markers of inflammation and coagulation (interleukin-6, C-reactive protein, serum amyloid A, fibrinogen, factor VIII, von Willebrand factor and Clara cell protein in plasma). the authors concluded that the study suggests that hydrogen peroxide is slightly irritating at 2.2ppm, but not at 0.5 ppm.