Builds up in the kidney. At high enough doses causes lung damage, high blood pressure, heart ailments, cancer, chronic fatigue syndrome, Alzheimer's and reproductive problems. Canada, Europe, Australia have imposed limits. The U.S. has not. There is no safe level according to a physician at the National Lead Information Center.
Children are especially vulnerable.
That's why lead levels in paints and gas are regulated. Not so in food fertilizers. According to the Seattle Times, the fertilizers you buy in your hardware store may have Bay Zinc's toxic tire ash in it. Zinc granules without the lead and cadmium are white, they report. It exports them to Canada, Mexico and Australia.