Dermal Absorption of Chemicals: Some Australian Regulatory Considerations

Abstract

A wide range of chemicals in formulated products are used in, and around, the average residential dwelling and occupational workplace. Intentional or inadvertent exposure to these chemicals may occur via the dermal, inhalation, and oral routes. However, the main route of exposure for the majority of products is the dermal route. A key step in the regulation of chemicals that are used in these settings is to ascertain their safety. This is usually done with a risk assessment. An important element of a risk assessment is to provide a quantitative estimate of the extent of both dermal exposure and the resultant internal (or systemic) dose. This chapter focuses on the estimation of internal dose once dermal exposure has been determined. Practical aspects of the process of extrapolation from animal data in the estimation of human risk are also discussed using data for two insect repellents, picaridin, and dimethyl phthalate (DMP), as examples.