Fels naphtha Laundry Soap (Purex Corp) contains the following:

        Sodium tallow-coconut oil soap   > 45%
        Clay                                                 30%
        Sodium Silicate                                 5%
        Naphtha                                           1-5%
        Titanium Dioxide                             < 1%
        Coloring, perfume, water

The only ingredient I would be concerned about is the Naphtha.  Naphtha is a
petroleum distillate like paint thinner,  or kerosene.   It actually might
work quite well on poison ivy,  but it could be real irritating to affected
skin.  The irritant in Poison Ivy is an oleoresin called Urushiol that is
degraded by soaps and detergents.

twh
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T.W. Hale, Ph.D.
Associate Professor of Pediatrics
Texas Tech University School of Medicine

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