Yep, basically this.

Bullets have lead in them.

Lead is actually fairly fragile, malleable, degradeable, and also of course, a neurotoxin, in high enough concentrations.

People that handle guns and/or ammo extremely regularly?

In many cases they use gloves, in some cases even masks.

Kinda like how xray techs get the (ironically, lead) shielding, but you don't: its the dosage, the exposure.

Most legit gun ranges in most states have a whole set of regulations and systems/practices in place to handle all that lead.

I'm not sure exactly how indoor ranges do it, but most outdoor ranges in most states, the backstop birm that catches all the bullets?

Gotta adhere to different kinds of water drainage requirements, do something like dig the whole thing up and process it in some way, to literally get the lead out, every so many years.

Even when guns aren't being fired, you've got similar sorts of safe handling practices for armorers/armories, people that recase (wrong term?) spent brass to make their own rounds, people that are very often doing basically surgery on guns, etc.