jones_supa writes "Since August, beekeepers around the town of Ribeauville in the region of Alsace, France have seen their bees starting to produce honey in an odd blue or green color. Mystified, the beekeepers embarked on an investigation and discovered that a biogas plant 4 km away has been processing waste from a plant producing colorful M&M candies. Subsequently the bees had been carrying the waste to their nests. Agrivalor, the company operating the biogas plant, said it had tried to address the problem after being notified of it by the beekeepers. 'We discovered the problem at the same time they did. We quickly put in place a procedure to stop it,' told Philippe Meinrad, co-manager of Agrivalor."