Consumer advocacy groups across the country are fighting to ban certain pesticides they say are rapidly killing the nation’s honeybee population.

The U.S. Public Interest Research Group is among the organizations lobbying the Environmental Protection Agency to ban the pesticides, known as neonicotinoids, which are commonly used on crops. When people treat seeds with neonicotinoids, the chemicals end up in the pollen and flowers of the crops, which the bees interact with when pollinating.

From April 2016 to April 2017, beekeepers across the U.S. lost a third of their honeybee colonies, according to a University of Maryland study. Honeybees, which were brought to the U.S. by European settlers, pollinate at least 90 percent of all commercially grown crops in North America. Some crops, such as almonds, are pollinated by honeybees alone.

The Arizona chapter of PIRG is raising awareness and building support in the state. They’re exploring options to limit the use of the pesticides, including introducing private sale bans, prohibiting use on state buildings or asking universities to stop using them.