Bacillus thuringiensis subsp. kurstaki (Btk) is a strong pathogen toward lepidopteran larvae thanks to specific Cry toxins causing leaky gut phenotypes. Hence. Btk and its toxins are used worldwide as microbial insecticide and in genetically modified crops. https://www.bekindtopets.com/save-now-Aqua-Pure-3MFF101-Full-Flow-Drinking-Water-System-Replacement-Cartridge-flash-choice/