Dr Wankel

I am planning on running some higher octane fuel at the track this summer. I have a oil company near me that carries 100-octane low lead fuel, this fuel is only .05% lead. My question for you guys is this. I have a high-flow cat in my car so I don't want to run the full race fuel (110) that I can get here because I don't want to clog the cat. But is only .05% lead still too much to run

If it is ok to run with that little bit of lead in it, then at what point does a fuel have too much lead content and will start to cause damage.

Thanks