McKay, Donald. "Front matter" Multimedia Environmental Models ...

Whereas simple lethality experiments can be designed using air, water, or food as
vehicles for chemical exposure, it is not always clear how concentrations in the solid
matrices of soils and sediments relate to exposure or intake of chemical by organisms.
It is difficult to design meaningful bioassays involving interactions between organisms,
soils, and sediments. One approach is to decree that whatever target fugacity
is developed for water be applied to sediment. This effectively links the target
concentrations by equilibrium partition coefficients.
A second method is to use concentrations to estimate exposure or dosage in units
such as mg/day of chemical to an organism, which for selfish reasons is usually a
human. Individual and total dosages can be estimated to reveal the more important
routes. This calculation of dose is enlightening, because it reveals which medium
or route of exposure is of most importance. Presumably, steps can then be taken to
reduce this route by, for example, restricting fish consumption.
Table 8.5 lists representative exposure quantities for several human age classes.
Table 8.5 Representative Exposure Rates for Four Human Age Classes Derived
Principally from the EPA Exposure Factors Handbook
Age Classes
Route