Total lead tells you your symptoms today. But it accrues so you'd need to know in advance your future lead intake to know if this small amount today will be a

Total lead tells you your symptoms today. But it accrues so you'd need to know in advance your future lead intake to know if this small amount today will be a big impact tomorrow. Basically its unknowable so its practical to say that no amount is safe. There probably does exist a low enough level that the body can even clear it but there isn't any will to define it.