[ghaff]

Basically all older houses in the Northeast US--which as you say is many of them--have lead paint to greater or lesser degrees. (As well as elsewhere of course. It's just that the average age in the Northeast tends to be older.) If you get new windows installed for example, the installers just assume they have to take lead mitigation efforts. There's really not much you can do about it other than covering it up with new paint.