I just noticed a warning on our (interior) Christmas tree lights, warning me that the State of California has determined that ingestion of lead is dangerous and that users should, after installing/touching these lights, thoroughly wash their hands.
Why is lead (paint?) used?
Are all Christmas tree light strands covered with lead paint?
Anyway, I would certainly wash my hands after handling lead. There is no known minimum safe level for exposure to lead. (The primary issue here is the migration of the lead from one’s hands to being ingested.)