Lead in life jackets?

I ordered a new type III PFD today to replace the type I that I do not find very comfortable. When it came it fit quite well and looks durable and I am happy with it, but I am puzzled by a tag that is hanging from it. The tag says something to the effect that "this life jacket contains lead and other products known to the State of California to cause cancer and birth defects. Do not touch your mouth after touching this life jacket without washing your hands first". None of that is surprising to me except that it includes lead. I would have thought that lead would be the last thing you would want on a life jacket other than maybe concrete, but I am hoping that there is some reasonable explanation that someone knows about and that they will be kind enough to enlighten me.

Zach