New life for 19th-century plants
(PHYSorg.com Biology)

Humans have long had a knack for concentrating heavy metals that would otherwise remain at low concentrations within the environment. These human-produced pollutants can be found going back as far as one million years ago with fires in caves during the Paleolithic Era, to industrial development in the 19th century, to increased concentrations of contaminants like cadmium and lead in the 20th century.