Muhammad F, Monteiro-Riviere N A, Baynes R E, Riviere J E
Center for Chemical Toxicology Research and Pharmacokinetics, College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina 27695, USA.
J Toxicol Environ Health A. 2005 May 14;68(9):719-37. doi: 10.1080/15287390590925456.
The percutaneous absorption of topically applied jet fuel hydrocarbons (HC) through skin previously exposed to jet fuel has not been investigated, although this exposure scenario is the occupational norm. Pigs were exposed to JP-8 jet fuel-soaked cotton fabrics for 1 and 4 d with repeated daily exposures. Preexposed and unexposed skin was then dermatomed and placed in flow-through in vitro diffusion cells. Five cells with exposed skin and four cells with unexposed skin were dosed with a mixture of 14 different HC consisting of nonane, decane, undecane, dodecane, tridecane, tetradecane, pentadecane, hexadecane, ethyl benzene, o-xylene, trimethyl benzene (TMB), cyclohexyl benzene (CHB), naphthalene, and dimethyl naphthalene (DMN) in water + ethanol (50:50) as diluent. Another five cells containing only JP-8-exposed skin were dosed solely with diluent in order to determine the skin retention of jet fuel HC. The absorption parameters of flux, diffusivity, and permeability were calculated for the studied HC. The data indicated that there was a two-fold and four-fold increase in absorption of specific aromatic HC like ethyl benzene, o-xylene, and TMB through 1- and 4-dJP-8 preexposed skin, respectively. Similarly, dodecane and tridecane were absorbed more in 4-d than 1-dJP-8 preexposed skin experiments. The absorption of naphthalene and DMN was 1.5 times greater than the controls in both 1- and 4-d preexposures. CHB, naphthalene, and DMN had significant persistent skin retention in 4-d preexposures as compared to 1-d exposures that might leave skin capable of further absorption several days postexposure. The possible mechanism of an increase in HC absorption in fuel preexposed skin may be via lipid extraction from the stratum corneum as indicated by Fourier transform infrared (FTIR) spectroscopy. This study suggests that the preexposure of skin to jet fuel enhances the subsequent in vitro percutaneous absorption of HC, so single-dose absorption data for jet fuel HC from naive skin may not be optimal to predict the toxic potential for repeated exposures. For certain compounds, persistent absorption may occur days after the initial exposure.
尽管这种暴露情况是职业常态，但此前尚未对经皮暴露于喷气燃料的皮肤对局部应用的喷气燃料碳氢化合物（HC）的经皮吸收情况进行研究。将猪每日重复暴露于用JP - 8喷气燃料浸湿的棉织物中，暴露1天和4天。然后将预先暴露和未暴露的皮肤制成皮片，置于流通式体外扩散池中。给5个装有暴露皮肤的细胞和4个装有未暴露皮肤的细胞加入由壬烷、癸烷、十一烷、十二烷、十三烷、十四烷、十五烷、十六烷、乙苯、邻二甲苯、三甲苯（TMB）、环己基苯（CHB）、萘和二甲基萘（DMN）组成的14种不同HC的混合物，以水 + 乙醇（50:50）作为稀释剂。另外5个仅装有JP - 8暴露皮肤的细胞仅加入稀释剂，以确定喷气燃料HC在皮肤中的滞留情况。计算所研究HC的通量、扩散系数和渗透率等吸收参数。数据表明，乙苯、邻二甲苯和TMB等特定芳香族HC通过1天和4天JP - 8预先暴露的皮肤的吸收分别增加了两倍和四倍。同样，在4天的JP - 8预先暴露皮肤实验中，十二烷和十三烷的吸收比1天的实验中更多。在1天和4天的预先暴露中，萘和DMN的吸收比对照组大1.5倍。与1天暴露相比，CHB、萘和DMN在4天预先暴露中有显著的皮肤持续滞留，这可能使皮肤在暴露后数天仍有进一步吸收的能力。喷气燃料预先暴露的皮肤中HC吸收增加的可能机制可能是通过傅里叶变换红外（FTIR）光谱所示的从角质层中提取脂质。这项研究表明，皮肤预先暴露于喷气燃料会增强随后HC的体外经皮吸收，因此来自未接触过喷气燃料的皮肤的单剂量吸收数据可能无法最佳地预测重复暴露后的毒性潜力。对于某些化合物，在初始暴露数天后可能会发生持续吸收。
