Fenoxycarb is a non-neurotoxic carbamate insecticide that acts as an insect growth regulator via juvenile hormone-like activity. It inhibits terminal development of first instar and newly transformed second instar nymphs of Florida red scale (C. aonidum) when used at a concentration of 0.0125% AI. Fenoxycarb (5 and 10 mg AI/colony) reduces the colony size index of laboratory colonies of red imported fire ants (S. invicta) by 93.6 to 95.9% at 8 weeks post-treatment. It is toxic to D. magna (LC50 = 0.5 mg a.s./L) and fish including O. mykiss, L. macrochirus, C. carpio, I. punctatus, and C. variegatus (LC50s = 0.66-1.5 mg a.s./L), but is not toxic to rats (LD50 = >10,000 mg/kg). Fenoxycarb is also an antagonist of α4β40-, α4β2-, α3β4-, and α3β2-containing rat nicotinic acetylcholine receptors (nAChRs; IC50s = 3, 2.4, 1.8, and 7.6 μM, respectively) but not rat brain acetylcholinesterase (AChE; IC50 = >1,000 μM).
