The effects of lead are real. There was a noticeable increase in the average IQ of Americans when lead was banned from auto gas. Some people are more affected than others, some show almost no ill effects: We had one guy at work who could just about eat lead, and still never had issues in any one of the blood tests we did from time to time for employees who worked in that department. Others had to be disqualified from working in that department because it seemed no matter what precautions they took, their blood levels shot up into the caution range. (Children are especially susceptible, since their brains are still developing.) You may be one of the lucky ones who can metabolize lead easily, or you just never got much exposure. For others, why take the chance if you don't have to?