when was it discovered that lead was poisonous
Lead poisoning In 2013 lead is believed to have resulted in 853,000 deaths.[2] It occurs most commonly in the developing world.[2] Those who are poor are at greater risk.[2] Lead is believed to result in 0.6% of the world's disease burden.[5] People have been mining and using lead for thousands of years.[4] Descriptions of lead poisoning date to at least 2000 BC,[4] while efforts to limit lead's use date back to at least the 1500s.[5] Concerns for low levels of exposure begin in the 1970s with there being no safe threshold for lead exposure.[2][4]