While honey bee die-offs often called "colony collapse disorder" have been increasing for several years, so has scientific evidence that a widely used class of pesticides called neonicotinoids could well be an important contributing cause. In 2011, EPA said it would review its approval on one such pesticide. Now it says it expects to finish in five years.
"Back in 2010, when I first started writing about the possible link between a ubiquitous class of pesticides called neonicotinoids and declining honeybee health, major media organizations largely ignored the story. Since then, evidence of the link has piled up in peer-reviewed studies—and now the bug killers, marketed by European chemical giants Syngenta and Bayer, are under suspicion for killing birds, too. Finally, big media are taking note. In recent weeks, The New York Times editorial page, NPR's generally agribiz-friendly Dan Charles, and CBS News have all weighed in with reports on the suspect pesticides and their effects on honeybees. Meanwhile, the annual bee die-offs that have come to be known as 'colony-collapse disorder' appear to be accelerating."