Donating blood?

I'm working on my eagle scout project, which is going to be organizing a blood drive. As a part of this, i will be donating blood. On the site for the blood bank it just says you can't donate if you have used IV drugs, which doesn't apply to me. I was just wondering if herb would show up on some sort of screening for the blood donation (If they do check for it)

and yes, i realize the irony in this project.;)

Donate away, they don't test for THC.

awesome. thanks. I realized while planning the project today that i should donate too, i was just worried about it. thanks again