Human exposure to acrolein: Time-dependence and individual variation in eye irritation

The aim of the study was to examine the time dependence on sensory irritation detection following exposure to threshold levels of acrolein, in humans. The exposures occurred in an exposure chamber and the subjects were breathing fresh air through a mask that covered the nose and mouth. All participants participated in four exposure conditions, of which three consisted of a mixture of acrolein and heptane and one of only heptane. Exposure to acrolein at a concentration half of the TLV-C lead to sensory irritation. The perceived sensory irritation resulted in both increased detectability and sensory irritation after about 6.8 min of exposure in 58% of the participants. The study confirm the previously suggested LOAEL of about 0.34 mg/m³ for eye irritation due to acrolein exposure. The sensory irritation was still significant 10 min after exposure. These results have implications for risk assessment and limit setting in occupational hygiene.