[wildfyr]

What about Fe(II) and Fe(III)? They both have strong interactions with catechol (same functional group) and are totally harmless. Both should be checked, they do different chemistry.

[jparker9141]

Hi Wildfyr,
There is a good discussion in the patent document about various metal salts that would work equally well as manganese, but he rejects them for various reason. Apparently ferric chloride would work well to deactivate the urushiol, but can discolor the skin.

[rolnor]

If you want to sell this kind of ointment or spray you would have to make clinical trials, MnCl2 would never be possible to use. If you yourself want to try it once or twice its fine I think. I think its completely useless.

[jparker9141]

Hi rolnor,
I'm not looking to sell the product. In fact, I just did some searching and it's already for sale on Amazon as Dr West's Poison Ivy Wash. Dr. West (now deceased) is the inventor of the patent mentioned on this thread. He was a chemistry professor at LSU.

He uses Manganese sulfate. All the testimonials are favorable, so maybe it really works. At $15 for a 4 oz bottle I'd rather mix up my own.

[jparker9141]

This brings up a question for the chemistry experts here. In your opinion, from what you know of the chemical nature of urushiol, would manganese sulfate (in an aqueous solution) react with, and deactivate it?

[rolnor]

The question is if this solution need to be applied imidiatley after exposure, then there is some chans it can react with the catechol. It seems unlikely that it can penetrate the skin and react fast enough to deactivate. The slow process is the allergic reaction but then its to late, the toxin is already bonded to protein in the skin, mangan can not break this bond I think. The fact that it is commercially available does give it som credability but it can be useless or near-useless.

[hollytara]

There are products that use bentoquatam - a type of bentonite clay.  Used to be called "IvyBlock" but that brand isn't around anymore.  Idea was to put it on the skin BEFORE possible exposure.  The bentonite was supposed to absorb the uroshiol so it doesn't get on the skin. 

Now there is one called IvyX that is supposed to do the same thing - but it has different ingredients - it is an aloe gel based material. 

[rolnor]

That sounds better, or just use gloves...

[hollytara]

I can see uses for each type of product:

You are going out to do yard work or to go for a hike - you know you might be exposed to poison ivy.  A preventive compound spread on any exposed skin would seem to be best. 

You are outside - didn't expect to encounter posion ivy, but think you might have been exposed to it - a wash that destroys or chelates the uroshiol is useful. 

I have also seen a scrub called Zanfels that is supposed to get the uroshiol out of the skin - I think it used micron sized polystyrene beads (which may no be banned, come to think of it).