Exposure multiroute

Fisher JW, Whittaker TA, Taylor DH, et al. 1989. Physiologically based pharmacokinetic modeling of the pregnant rat A multiroute exposure model for trichloroethylene and its metabolite, trichloroacetic acid. Toxicol Appl Pharmacol 99 395-414. 

Some children are exposed to toxic chemicals or to hazardous environments in unique circumstances. There is a need to understand chemical exposures and other health stressors in special settings in the world (child labourers, street children, refugees). Globally, millions of children live under these conditions. Currently, data on children s exposures are inadequate to effectively assess multimedia and multiroute exposures in order to conduct child-protective risk assessments. The limited exposure data that are available have focused on children in developed countries, and information on the levels of chemical exposures in children in developing countries is generally lacking. 

Figure A2.1 Multimedia, multipathway, multiroute exposure assessment...

Most attempts at describing CWA PK and PD have used classical kinetic models that often fit one set of animal experimental data, at lethal doses, with extrapolation to low-dose or repeated exposure scenarios having limited confidence. This is due to the inherent nonlinearity in high-dose to low-dose extrapolations. Also, the classical approach is less adept at addressing multidose and multiroute exposure scenarios, as occurs with agents like VX, where there is pulmonary absorption of agent, as well as dermal absorption. PBPK models of chemical warfare nerve agents (CWNAs) provide an analytical approach to address many of these limitations. 

Krishnan, K., and Carrier, R. (2008). Approaches for evaluating the relevance of multiroute exposures in establishing guideline values for drinking water contaminants. J Environ Sci Health C Environ Carcinog Ecotoxicol Rev 26, 300-316. 

---