"Summit" of Baltimore is marketing a product called "Mosquito Dunks" to kill
mosquito larvae in standing water.  The active ingredient is Bacillus
thuringiensis subsp. israelensis primary powder [7000 Aedes aegypti (AA)
International Toxic Units (ITU) per mg. primary powder].  The product is
sold as doughnut-shaped rings, about the size of a small doughnut.
According to the write-up on the package, when a ring is thrown into water,
it floats, and over about thirty days dissolves into the water.  At first
the material floats as a surface film which gradually settles into the water
where it is eaten by mosquito larvae and kills them.  There is no
information in or on the package regarding toxicity to other insects.

Does anyone know whether this stuff is toxic to honeybees?

Walter Weller