ABSTRACT
Given the paucity of the in vivo W-I effect data, and that reports of the in vitro W-I effect have mainly come from the Moody laboratory albeit a few reports from other labs exist (1), the authors contend it is possible the in vitro W-I effect is at least partially an artifact of the in vitro methodology used (Fig. 57.2) as will be discussed under skin depot bioavailability. However, since the W-I effect was observed with different pesticides in different animal species of skin including hairless guinea pig, rat, pig, human, and human tissue cultured skins, and in both the Bronaugh and Moody cell tests, it is essential given the potential adverse toxicologic implications of the W-I effect, that further studies be conducted to verify/validate this effect in vivo. Prior to addressing such adverse health effects, the relevance here of skin depot bioavailability is discussed.
