I did not know the compound Azadirachtin, so I did just a simple search in google
including Euphorbin, which I indeed already knew:
Euphorbia spp. (EUPHORBIA, MILK BUSH, POINSETTIA, SNOW-ON-THE-MOUNTAIN, SPURGES); latex; gastrointestinal tract affected by the toxin
euphorbin;
E. pugniformis
The latex is a violent emetic and purgative and is used by natives for the purpose of curing indigestion and constipation. The sap is highly irritant, however. A case of death from drinking a concoction of the plant is on record. A yellow resinous substance in this plant called
Euphorbin can cause terrible blistering of the skin.
Euphorbin a deadly resinoid...
Azadirachtin is biodegradable (it degrades within 100 hours when exposed to light and water) and shows very low toxicity to mammals (the LD50 in rats is >3,540mg/kg making it practically non-toxic), thus being environmentally sound.
Of course, whether a poisonous compound would kill you at one dose or after 10 years depends only on the concentration used... however, I would be carefull
Note: this applies not only to Dane, but also to most pest control products and many fertilizers you can buy for your household...
now, as for Dane... I have no experience with this product, but Azadirachtin seems to be a good insecticide (it is part of neem oil).