Thanks for the great suggestion. I love these types of postings as they get me to thinking (think crazed woman sitting behind computer with lightbulb on over her head :-)). Formula 409 is one of those products that I keep around for that really dirty, grimy, oily mess yet I never thought of it for use to clean up urushiol oil. I certainly can see that it would work well. Formula 409 is a detergent. Detergents are effective for cleaning as it contains surfactants (soap is a surfactant) and was developed to work in conditions where soap is less effective such as hard water. Here is a great site with more information about soaps and detergents: The Soap and Detergent Association. This is a very nicely done website with some very interesting information. If you go to the "Cleaning Products Overview" section you can learn about the history and the chemistry of soaps and detergents.