Toxicity Studies of Microbial Insecticide Bacillus thuringiensis var. kenyae in Rats, Rabbits, and Fish

Abstract

Bacillus thuringiensis var. kenyae (B.t.k.) is a microbial insecticide effective against lepidopteran pest species. Acute oral toxicity in rats and acute dermal toxicity, ocular irritation, skin irritation in rabbits were studied for the wettable powder formulation of B.t.k. In addition, toxicity of the wettable powder formulation was also studied in fresh water fish (Gambussia affinis). The results of these studies indicate that this wettable powder formulation of B.t.k. is nontoxic and nonirritant to rats, rabbits, and fish.

Genotoxic evaluation in Oreochromis niloticus (Fish: Characidae) of recombinant spore–crystal complexes Cry1Ia, Cry10Aa and Cry1Ba6 from Bacillus thuringiensis

“…A concentration-effect relationship was not observed, which means that these results are not sufficient to conclude that Cry1Ia spore-crystal is genotoxic. A similar result was observed by Meher et al (2002), showing that formulations containing Bacillus thuringiensis var. kenyae (B.t.k.)…”

Toxicological Examinations Following Oral Administration of Bacillus thuringiensis var kurstaki Biological Insecticide in Wistar Rats

“…In another study, the acute oral toxicity of GM B. thuringiensis supplemented with an additional N-acyl homoserine lactones gene were studied in Wistar rats. 37 In contrast with the findings of this study, Meher et al reported that acute oral administration of B. thuringiensis in rats has no adverse effects. 37 Previous studies also demonstrated that different doses of B. thuringiensis did not have acute toxicity following the administration in rats.…”

Physiological parameters of Piaractus mesopotamicus (Osteichthyes: Characidae) exposed to a biopesticide based on Bacillus thuringiensis

“…In addition, changes in AST plasma levels suggests that the heart and skeletal muscles can had be affected by the action of Bt. However, it has been reported that biopesticides based on Bt are not toxic to fish (Jackson et al 2002, Meher et al 2002, Ahmad et al 2011. The hematocrit is a good indicator of the adverse effects of environmental factors to fish Mataqueiro 2004, Ranzani-Paiva et al 2013).…”

“…Studies reported that Bt has no toxicity to non-target species, including fish (Jackson et al 2002, Meher et al 2002, Ahmad et al 2011, but it produces toxic and highly specific proteins against protozoans, insects, helminths and mites of agricultural and veterinary importance (Mendozaestrada et al 2016). Thus, Bt has been recommended for control of trematodes Centrocestus formosanus in ornamental fish (Mendoza-Estrada et al 2016).…”