Assessment of asphalt workers' dermal exposure.

We agree with McClean and his co-workers (McClean et al., 2004) that urinary 1-hydroxypyrene concentration is a useful measure of total absorbed dose of polycyclic aromatic hydrocarbons (PAHs). Many occupational health studies have reported low correlations between inhalation exposures and urinary 1-hydroxypyrene levels, suggesting that other exposure routes (in particular dermal, but also ingestion) play a role, as well as non-occupational PAH sources. However, we do not agree that the data presented by McClean et al. justify the estimate of an 8-fold higher contribution of the dermal route than the inhalation route during asphalt paving work for the following reasons: