Photo credit: Ben Phillips

Neonicotinoids are the most widely used class of insecticides in the world. They are systemic pesticides, which means that rather than simply residing on the surface of the plant, they are taken up and distributed internally throughout the stem, leaves, flowers, nectar and pollen. A recent study published in Science sought to better understand the global distribution of neonicotinoids in the environment by sampling honey. Scientists tested almost 200 honey samples from across the globe (all continents except Antarctica) for the presence and concentration of neonicotinoids. They found that 75% of honey samples contained at least one neonicotinoid, with 86% of North American, 80% of Asian, and 79% of European honey testing positive. The average concentration of neonicotinoids in the honey tested was 1.8ng/g – a concentration known to cause negative health effects in bees. ”Our results, combined with the growing body of evidence for detrimental effects on bees and other nontarget invertebrates, suggest that a substantial proportion of world pollinators are probably affected by several neonicotinoids,” the authors wrote.