INFLAMMATORY DAMAGE TO SKIN BY PROLONGED CONTACT WITH 1,2-DICHLOROBENZENE AND CHLOROPENTAFLUOROBENZENE

Skin samples from Fischer-344 rats and Hartley guinea pigs exposed der mally to 1,2-dichlorobenzene (DCB) and chloropentafluorobenzene (CPFB) for up to 4 h were examined for chemical-induced damage. Samples were stained with hematoxylin and eosin and scored for polymorphonuclear c ell (PMN) margination, dermal inflammation, and epidermal necrosis by light microscopy. Ultrastructural evaluation of samples fixed with 2% glutaraldehyde and postfixed with 1% osmium tetroxide was used to visu alize margination of PMNs. Guinea pigs exhibited postexposure inflamma tory changes following an exposure of about an hour-and-a-half shorter duration than rats. DCB-induced inflammation and PMN margination occu rred following an exposure about a half hour shorter in both species c ompared to CPFB. In contrast, epidermal necrosis was more severe with CPFB than with DCB. These changes may account for decreases in chemica l penetration rates which have been observed in previous studies with DCB and CPFB in rats and guinea pigs. (C) Wiley-Liss, Inc.