The particulate respirator will protect you during the cutting of the bullet but it won't prevent the area you are working in being contaminated with lead dust. Which will end up on your hands and your family's hands everytime they touch anything in that area and will eventually find its way into your mouths.
There is no lead in gasolene anymore so there is no reason anyone would get lead poisoning that way.
We are talking about cutting up a bullet or couple bullets correct? When did lead become the most hazardous metal in the world?
Correct on lead free vehicle fuels. Everything else must in gas must be roses.