Evaluation of skin sensitization potential of jet fuels by murine local lymph node assay

Jet A and JP-8 are the major jet fuels used in civilian and military (US Ai r Force) flights, respectively. JP-8 + 100 is a new jet fuel recently intro duced by the US Air Force. Besides lung exposure, skin is the potential rou te of exposure to jet fuels. The purpose of the present study was to invest igate the skin sensitization potential of jet fuels (Jet A, JP-8 and JP-8 100) using murine Local lymph node assay (LLNA). Female CBA/Ca mice (8-12- weeks-old) were used in the study. Dinitrochlorobenzene (DNCB, 0.25% w/v) a nd paraaminobenzoic acid (PABA, 2.5% w/v) were used as positive and negativ e control, respectively and acetone: olive oil (4:1, AGO) was used as the v ehicle (control). All three jet fuels caused a proliferative activity signi ficantly greater than the control (P < 0.01). Our results demonstrate that JP-8 is a weak skin sensitizer [stimulation index (SI) = 3.17]. The SI of J et A and JP-8 + 100 were 2.44 and 2.38, respectively, hence are not conside red as skin sensitizers. Interestingly, the SI of JP-g with butylated hydro xytoluene (BHT) was consistently lower than JP-8, though the difference was not statistically significant (P > 0.05). BHT, which is an antioxidant add itive of JP-8 + 100, reduced the skin sensitization potential of JP-8. Furt hermore, the lower SI of JP-s + 100 could be partially attributed to the pr esence of BHT. The findings reported here suggest that care should be taken to minimize dermal exposure to jet fuels especially JP-8 to avoid skin sen sitization. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.