Some experts also believe a group of pesticides, named neonicotinoids (nee-oh-NIK-uh-teen-oydz), could be linked to bee die-offs as well. These chemicals are used to kill off insects that eat crops, but they may be harming bees too. The U.S. Environmental Protection Agency is currently studying the risk these pesticides pose to bees and other pollinators. The agency says it won’t approve new uses for the chemicals until it has more information on their safety.