ABSTRACT
A wide range of chemicals in formulated products are used in, and around, the
average residential dwelling and occupational workplace. Intentional or inadver-
tent 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.
