Does foray48b cause issues for the endocrine system?

Probably Not. Foray 48b (btk) is an insecticide using spores from a bacteria to kill gypsy moth larvae. While there have been reports of allergic resctions, these would generally manifest themselves as asthma affecting the respiratory system, or theoretically as anaphylaxis causing shock. There are no us government sites linking foray 48b to any endocrine disease.