[Identification of automotive lubricants and other heavy oils by isotachophoresis].

Automotive lubricants were analysed by isotachophoresis for the purpose of identification of lubricants and suspected stains adhered to victims in traffic accidents. As the results, it was found that each lubricant showed a characteristic isotachophreogram even if they were manufactured by the same maker, and that the isotachopherogram of the lubricant changed in proportion to the running distance of an automobile. Each lubricant had its own changing rate. Moreover, A, B, C heavy oils, asphalt, soy sauce and sauce, which apparently resembled lubricants when they adhered to victims, were analysed with this method. They were found to be clearly different from lubricants in isotachopherogram and they could be discriminated from lubricants. Therefore, it was found that lubricants could be easily identified or discriminated from other lubricants such as engine oils, gear oils and other oils by comparing their isotachopherograms obtained with this method in a short time. It was, however, difficult to suggest the maker of a lubricant from isotachopherogram. We conclude from these observations that isotachophoresis method is useful for the analysis of lubricants in case of traffic accidents.