Lead doesn't leave your blood system. Unless you lay off to see if your levels don't increase, the amount will not decrease. I would suspect poor ventilation- one reason I hate using indoor ranges
I know the above post is 3 years old but a lot of people believe it. You lose lead every time you expel bodily fluids because the lead shows up everywhere, sweat, urine spit, you name it if it leaves your body miniscule amounts of lead go with it. Picked up most of my lead when I was teaching and spent 5-6 hours a week inside an old indoor range. Since then I have lost over a third of what it used to be. Took 30 years but it's gone and I only shoot outdoors now. I cast inside but my pot is under a hood and vented outside with a pretty nice blower sucking up the fumes.
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