DERMAL ABSORPTION OF CHEMICALS FROM LIQUID MIXTURES

描述：工作场所是危险化学品与皮肤接触的最常见场所之一。识别皮肤接触危害对于控制皮肤接触危害至关重要。不幸的是，目前识别的化学品作为皮肤吸收的危害是不一致的，记录不足，定性。因此，那些负责保护工作场所人类健康和安全的人被迫在几乎没有信息的情况下就安全或危险程度以及所需的个人保护类型作出判断。这项研究工作的最终目标是为职业安全和健康从业人员提供有关职业皮肤接触潜在危险水平的更好指导。 虽然大多数职业性皮肤接触涉及化学品的混合物，但多种成分与皮肤之间的相互作用仍然未知。拟议的研究是针对识别和理解 暴露于化学混合物，特别是非水溶液的影响。理解实验评价将仅限于一小部分的所有混合物遇到的职业，我们建议开发一个基本的理解的基础机制相结合的数据与数学模型。具体而言，我们将（i）通过实验研究几种测试溶质在水和四种非水溶液（甲苯、正辛醇、正辛烷和选定的氯化烃）中相互作用或皮肤相互作用以改变速率的程度 和/或化学吸收的量，（ii）开发用于估计含有两种或更多种有机化合物的水溶液和非水溶液的皮肤吸收的计算程序，以及（iii）演示和使用用于测量电化学阻抗的新方法，以表征皮肤屏障功能和非水溶液对其的影响。初步研究将涉及甲苯和正辛醇中的四种溶质（萘、菲、1-萘酚和1，3-萘）。选择这种溶质和溶剂的组合来检查相似和不相似化学品之间的相互作用，并评估吸收化学品和皮肤之间氢键相互作用的重要性。 这项研究工作的最终目标是建立一个框架，将皮肤吸收测量和液体混合物的预测以有用的指南的形式与工业健康科学家联系起来。有了这些信息，就有可能制定有效的接触控制和/或干预措施。

DESCRIPTION: The workplace is one of the most common venues for hazardous chemical contact with skin. Recognition of the dermal exposure hazard is essential for its control. Unfortunately, the present identification of chemicals as skin absorption hazards is inconsistent, poorly documented, and qualitative. As a result, those charged with protecting human health and safety in the workplace are forced to make judgments about safe or dangerous levels, and the type of personal protection required, with little or no information. The ultimate goal of this research effort is to provide occupational safety and health practitioners with improved guidance regarding potentially dangerous levels of occupational dermal exposure. While most occupational exposures of skin involve mixtures of chemicals, the interactions between multiple components and skin remain unknown. The proposed research is directed toward identifying and understanding the effect of exposures to chemical mixtures and especially non-aqueous solutions. Understanding that experimental evaluations will be limited to a small fraction of all mixtures encountered occupationally, we propose to develop a fundamental understanding of the underlying mechanisms by combining data with mathematical models. Specifically, we will (i) examine experimentally the extent to which several test solutes in water and in four non-aqueous solutions (toluene, n-octanol, n-octane and a selected chlorinated hydrocarbon) interact with each other or skin to alter the rate and/or amount of chemical absorption, (ii) develop computational procedures for estimating dermal absorption from aqueous and non-aqueous solutions containing two or more organic compounds, and (iii) demonstrate and use a new method for measuring electrochemical impedance to characterize skin barrier function and the effect of non-aqueous solutions thereon. Initial studies will involve four solutes (naphthalene, phenanthrene, 1-naphthol, and 1,3-naphthalenediol) in toluene and n-octanol. This combination of solutes and solvents were selected to examine interactions between similar and dissimilar chemicals, and to assess the importance of hydrogen bonding interactions between absorbing chemicals and skin. The ultimate goal of this research effort is a framework for relating dermal absorption measurements and predictions for liquid mixtures to industrial health scientists in the form of useful guidelines. With such information in-hand, it will be possible to plan effective exposure controls and/or interventions.