Beekeepers and researchers nationally are reporting growing evidence that a powerful new class of pesticides may be killing off bumblebees. Now, research points toward another potential cause: metal pollution from aluminum and nickel. A new study finds that bumblebees are at risk of ingesting toxic amounts of metals like aluminum and nickel found in flowers growing in soil that has been contaminated by exhaust from vehicles, industrial machinery, and farming equipment.

Source: Total buzz kill: Metals in flowers may play role in bumblebee decline