Polyester and epoxy are inert when fully cured. The problem that many people have is that they proceed with alien compounds long before the epoxy┬ or poly is fully cured which can take weeks.
A new kayak smells (out gassing) like polyester for many months after being made, and epoxy blushes and out-gasses for quite a while too.
Some interesting reading for tech people.
The Connyak BBS