Honeybee problem nearing a 'critical point' | Environment | guardian.co.uk

Of particular concern is a group of pesticides, chemically similar to nicotine, called neonicotinoids (neonics for short), and one in particular called clothianidin. Instead of being sprayed, neonics are
used to treat seeds, so that they're absorbed by the plant's vascular system, and then end up attacking the central nervous systems of bees that come to collect pollen. Virtually all of today's genetically engineered Bt corn is treated with neonics.