You are being incredibly selective in your reading and it's showing in your highlights. You deliberately didn't highlight the word "licensure" for instance in one of your quotes. You are literally following the climate denier playbook here and selectively choosing words in the non-conclusion parts of studies and glossing over the data parts. I don't know what to tell you other than have a nice day, cause I, nor the absolute mountain of evidence to the contrary of your belief, is going to convince you otherwise.

Just note to anyone else that stumbles upon this thread, there are literally hundreds of studies that have shown that firearm use and lead levels have a direct correlation. Here's an example of a review of some of those studies done by the NIH in regards to specifically firing ranges:

https://pmc.ncbi.nlm.nih.gov/articles/PMC5379568/

Results

Thirty-six articles were reviewed that included BLLs from shooters at firing ranges. In 31 studies BLLs > 10 μg/dL were reported in some shooters, 18 studies reported BLLs > 20 μg/dL, 17 studies > 30 μg/d, and 15 studies BLLs > 40 μg/dL. The literature indicates that BLLs in shooters are associated with Pb aerosol discharge from guns and air Pb at firing ranges, number of bullets discharged, and the caliber of weapon fired.

Furthermore the conclusion is not a "may be" no matter how much anyone wishes it to be so:

Shooting at firing ranges results in the discharge of Pb dust, elevated BLLs, and exposures that are associated with a variety of adverse health outcomes. Women and children are among recreational shooters at special risk and they do not receive the same health protections as occupational users of firing ranges. Nearly all BLL measurements compiled in the reviewed studies exceed the current reference level of 5 μg/dL recommended by the U.S. Centers for Disease Control and Prevention/National Institute of Occupational Safety and Health (CDC/NIOSH). Thus firing ranges, regardless of type and user classification, currently constitute a significant and unmanaged public health problem. Prevention includes clothing changed after shooting, behavioural modifications such as banning of smoking and eating at firing ranges, improved ventilation systems and oversight of indoor ranges, and development of airflow systems at outdoor ranges. Eliminating lead dust risk at firing ranges requires primary prevention and using lead-free primers and lead-free bullets.