This is from cornell - "The key insecticidal ingredient found in the neem tree is azadirachtin, a naturally occurring substance that belongs to an organic molecule class called tetranortriterpenoids (
6). It is structurally similar to insect hormones called "ecdysones," which control the process of metamorphosis as the insects pass from larva to pupa to adult."
http://pmep.cce.cornell.edu/profiles/extoxnet/24d-captan/azadirachtin-ext.html
UC Davis soils lab -
http://casoilresource.lawr.ucdavis.edu/drupal/aggregator/categories/3?page=17 Here's another science journal - "Of the different combination of biocontrol agents tested in vitro, combination of Pf1+Tv1+ Bs16+neem cake+zinc sulphate+FYM was most effective in inhibiting the radial mycelial growth"
If you're a chemist you'll understand that the chemical azadirachtin in the seeds of neem is the same as the azadirachtin found in commercial insecticides and is the main insecticide found in neem. You'll also understand why it needs a stabilizer and how adding an organic stabilizer isn't changing the active chemical. Kind of like saying pyrethrum isn't organic because the bottle isn't 100% pyrethrum.
I'm not saying neem is bad - for most applications its a godsend.
Lemon juice is full of chemicals. By squeezing the lemon the chemicals aren't suddenly bad. And yes, lemon juice can be used in gardening. I know a few people that pH with it...which would be a chemical reaction...
I'm curious as to where you think your BT is coming from. Scraping it off the top of soil? And does it come as 100% BT?