I saw a documentary that mentioned the Romans did know that lead was poison, but as Pierrem15 said in a earlier post, the continuously flowing water, plus mineral deposits mitigated a lot of the risk.
It is amazing how the Romans engineered aquaducts and other structures to move water where it was needed. Truly amazing!
When I went to Pompeii there was a cast of a young women, she was pregnant. Her stature was about that of a 12 year old. The archeologist conducting our tour stated it was felt that Her diminutive stature was due to lead poisoning . We were told that lead pipes were used in wineries. The acidic nature of the grape juice desolved lead into the wine.
Interesting on how Romans used lead to sweeten wine. 1/2 of the Roman occupants of Roman London ,Londinium, are supposed to have suffered from lead poisoning. No,the Roman suffered from lead poisoning. https://www.ancient-origins.net/history-ancient-traditions/savoring-danger-sugar-lead-was-used-flavor-roman-food-and-wine-toxic-021771