The lead in those joints never touches liquid. It's a sealant on the back of the oakum, which is what does the actual water contacting.
Also, nearly all water supplies (municipal, at least) are pH adjusted to be slightly basic, which causes lead to form lead carbonates and oxides, which is (basically) insoluble in cold water. Still good policy to replace lead supply lines, but not a crisis unless you allow your water quality to fluctuate (ala Flint or a number of other US cities, sadly)
