Originally Posted by strader
I am looking to paint some of the previously stained and polyurethaned wood and was wondering if I should have any concerns about lead exposure.
Fairly sure lead ceased to be a paint component well before 1980. I doubt it was ever in varnish, never gave it a thought when sanding my varnish before recoating with more varnish. Temperatures here can be hot, I`ve never heard of general varnish failure on an IG, I suspect other causes, like moisture entry, or a poor previous refinish. If the suspect areas are around windows, that`s not unusual due to water ingress, mine were painted by a PO to disguise water damage.