Yes a small amount of lead has been alloyed into the majority of brass castings for over 80 years now, it makes machining the brass easier, giving smoother cuts and better tool life. This is the reason you can not use brass in alcohol stills, the ether vapours eat away at it, and the lead ends up in the alcohol. It has been deemed safe for use in water supplies and plumbing fixtures, but can leach in highly corrosive atmospheres and in contact with strong hot solvents.

It is fairly common practice to add a little extra zinc to molten brass, as it vapours away when molten, same goes for lead if you are intending to machine the final cast parts

It is used in tiny amounts (a few % at most) and added just before the pour so it doesn't all vapour off from the crucible. Using it as the main alloying element with copper is the one that creates problems



A little lead in brass also makes threaded components screw together smoothly, and reduces the likely-hood of binding causing part failure, it acts like a lubricant in tiny quantities.

Because most foundries use recycled brass as their feedstock for components, lead is in pretty much all brass now. You would have to buy certified alloys to ensure it was lead free.
Same goes for bronzes (copper/ tin) used in industry that are intended for machining.
Antimony has been used as a replacement for lead in pewter for many years, because of it leaching out when in contact with acidic foods and drinks. (no good for alcohol stills either as its highly toxic and dissolves in ether)