> People vary greatly in their sensitivity to urushiol. In approximately 15% to 30% of people, urushiol does not trigger an immune system response, while at least 25% of people have a very strong immune response resulting in severe symptoms.
I've also heard this about poison ivy. (I assume cashew plants have less of this irritant than poison ivy does.)
From what I've read, along with anecdotal experience, the opposite seems to be true. Its seems like you need to be exposed to urishiol a few times before you get a reaction to it.
Often subsequent reactions are worse than the initial.
Seems like it might vary just as much as poison ivy exposure, and for the same reason (or nearly so, since the plants may also have other irritating chemicals that aren't the same between species). Some people are totally immune to poison ivy and don't get any reaction from physical contact with it, although not too many.
https://en.wikipedia.org/wiki/Urushiol-induced_contact_derma...
and it notes that
> People vary greatly in their sensitivity to urushiol. In approximately 15% to 30% of people, urushiol does not trigger an immune system response, while at least 25% of people have a very strong immune response resulting in severe symptoms.
I've also heard this about poison ivy. (I assume cashew plants have less of this irritant than poison ivy does.)