Here's some interesting info from IPM of Alaska website:
PESTICIDE PROFILE:
AVERMECTIN/ ABAMECTIN/ IVERMECTIN
The three names are used to describe the same class of compounds. For simplicity, we will call it Avermectin here.
Introduction:
Avermectins are insecticidal/ miticidal compounds derived from the soil bacterium Streptomyces avermitilis. Avermectin is a natural fermentation product of this bacterium.
The pesticide is classified by the U.S. Environmental Protection Agency (EPA) as a class IV toxicity pesticide, or practically non-toxic. The compound has been fully evaluated by EPA for its effects on human health or the environment.
Use and Mode of Action:
The compounds act as an insecticide by interfering with the nervous system of the insect. This nervous system effect causes the insect to become paralyzed. Avermectin is used to control insect and mite pests of ornamental plants in greenhouses, it is used in veterinarian medicine for treatment of internal and external parasites and mites of pets and livestock, including scabies. It is also formulated into commercial baits for control of ants and cockroaches.
Toxicity:
Avermectin is highly toxic to insects and mites. Emulsifiable concentrate formulations used in greenhouses may cause slight to moderate eye irritation and mild skin irritation. At very high doses, it can affect mammals, causing symptoms of nervous system depression such as incoordination, tremors, lethargy, excitation, and pupil dilation. Avermectin is not readily absorbed through skin. Tests with monkeys show that less than 1% of dermally applied abamectin was absorbed into the bloodstream through the skin.
Ecological Effects:
Avermectin is highly toxic to fish and bees, therefore its use should be limited to screened greenhouses and structural pest bait formulations in Alaska. Bait formulations should be limited to child resistant enclosed bait containers, or crack and crevice baits, granular bait formulations should be applied by a licensed professional only. Veterinarian formulations for the treatment of parasites and mites afflicting livestock and pets should be administered by a licensed veterinarian or under the direction of a licensed veterinarian.
Well guys, I learned something new today.
I've just always had such good luck with the homemade recipe that I never thought to resort to this strategy. But it looks pretty good, the same as a thuricide, pyrethin or other naturally derived insecticide. It has its good & bad points but overall it's worlds safer than its commercial non-organic-in-origin toxic counterparts.
kathe