No, you can't say the same thing about lead. We understand the mechanisms in which lead poisons the body. We know that even low levels of lead exposure cause da

No, you can't say the same thing about lead. We understand the mechanisms in which lead poisons the body. We know that even low levels of lead exposure cause damage. And, we've measured this damage by comparing large samples sizes based on blood lead levels. Even a tiny amount of lead, like 3.5 mcg / dL measured in blood, is correlated with loss of IQ.