I have been dealing with my personal lead exposure for almost 50 years now. While it's good to see that the topic is getting aired on this forum, I am a little dismayed by the amount of BS in this thread. Tazman's post is about the only reality I see here. I have had high lead levels from body shop exposure back in the '60's with some additional lead roofing and plumbing exposure. I averaged in the mid 20's through my 20's with a high of 48 at age 40 after two years of indoor bullseye league. That got me a letter from the State of Maine and the EPA, along with a reading list.
Elemental lead is not particularly hazardous if you do not ingest it. Do not eat it, drink it or breath it. Wash your hands, do not suck your thumb, do not eat or drink while casting, do not smoke, (lead is the least of your worries if you smoke, why make it worse?) Common processes for boolit casting are well below the temp required to put lead in the air you're breathing, (1,200 deg +/-). Try not to leave the pot on without the thermometer in it. I've continued to cast for 20 years after my high reading and I'm back in the single digits today. The way lead typically gets in your system is through the oxides or various "salts" of lead, which are much, much more readily absorbed than elemental lead. Unfortunately lead oxide makes a great white pigment, (to a lessor extent yellow), so it was widely used in paints and glazes until the '60s. It is also easy to work, so it was used in early automotive body work, (my early exposure) And for a long time it was the major component of most solder. That said, people with lead boolits in their bodies do not die of lead poisoning, unless the projectile is in the gut or spinal fluid where it gets dissolved. Your body deals with lead by filtering it from the bloodstream and accumulating it in your bone marrow. Go too far down the bone marrow road and you are in trouble. Unfortunately once you reach the capacity of your bone marrow, there is not much else your body can do for you without some serious help. So, if you are a shooter or caster, lead level testing should be part of your regular physicals as any elevated level is a sign you need to look at your possible exposure sources before you use up your bodies capacity to deal with it.
The primary risk of exposure for shooters is lead oxide, (dull gray coating that forms on lead when exposed to air), and Lead styphenate which is a major ingredient in ammunition primer compounds. Both of these exposures are very prevalent at indoor ranges. The primer component is in the air you breath anytime someone is shooting and the lead oxide is being formed on all of the tiny particulates that result from boolits fragmenting on the backstops. That stuff gets everywhere. The best advice I can give you is:
1.Wear a common respirator at the indoor range, and really limit your time there, wash you hands and clothes when you're done.
2. Wash your range brass in soap and water before processing it further. Lead styphenate is very soluble, (that's why it is so easily absorbed), so it washes off easily. Do not breath the dust from your tumbler.
3.Don't put your fingers in your mouth while casting, cleaning brass, loading, or shooting.
Follow those three rules and 99% of shooters will be fine.
Symptoms of lead exposure are:
Irritability
Aches and pains
Headache
If you think about it, you will recognize the relationship between your exposure and the symptoms. Act on it when it happens.