When you shoot bits of the lead projectile get aerosolized as it rips through the barrel and caught in the expanding gas cloud of the propellant. This gets deposited on you and your clothes, especially at an indoor range. Since you can’t remove lead from your system this can build up over time.

I disagree for two reasons. First, there's lots of ammo that's non jacketed lead. Start with .22LR, which is probably the most common ammo.

Second, I didn't think the jacketing helps that much in either hunting or indoor range contexts. In hunting, the bullet mushrooms or fragments or disintegrates, dispersing it's kinetic energy through lots of tissue; that's how it kills. Disintegration means there are lots of tiny lead bits scattered in the meat. And at the range, if the bullet hits a hard backstop, it again disintegrates into even finer pieces, making lead dust.

Lead seems pretty bad to me. It's inherently neurotoxic and gets in the brain easily enough. If you are breathing in aerosolized lead regularly it has a real potential to do harm, even if it doesn't necessarily kill you there will be negative consequences.

Birds would disagree.

Gun shot residue contains lead particulate, which spreads onto your hands, arms, and face when shooting and can be ingested, for example, by handling food without cleaning your hands. Or cleaning a gun somewhere where you prepare or eat food.

Cheap .22 target loads, shotgun target loads, and even some birdshot are full of the stuff.

But, even if you don't shoot those often, lead is still in all smokeless powder and primers. Every time you fire a round of any kind, there's airborne lead being aerosolized. That's why indoor ranges are required to be ventilated and why many don't allow pregnant women in the shooting area.

Lead is "that bad". The health effects are serious and undeniable. But don't take my word for it, please educate yourself and do better: https://en.wikipedia.org/wiki/Lead_poisoning

Even if you don't care about your own health, lead exposure isn't taken seriously enough in our hobby, and your attitude makes all us look ignorant.