http://www.slate.com/articles/health_and_science/science/2015/08/lead_poisoning_a_history_of_lead_in_pipes_makeup_cups_wine_paint_and_gasoline.html

In a criminal lineup of the world’s metals, lead would be the dull, inoffensive-looking suspect. Next to the quicksilver fluidity of mercury, it is gray, solid, and dense. Judged against rigid iron, it melts and bends easily. Compared with the homicidal efficiency of white arsenic, it takes spoonfuls of black lead powder to off a victim—who would definitely notice the sweet taste.