The full length of B.t protein is inactive state. In the alkaline (p.H 10.5) condition the protein should be fragmented to release active toxic portion. The uniqueness of active toxic Cry protein is it binds with specific receptors present in the insect midgut and allows the Bt toxins to form pores leads to death of the insect.  The human digestive systems are acidic in nature (p.H 4.0 – 6.5) and don’t have the specific receptors. So the B.t proteins are cannot be fragmented to release active toxic protein and unable to bind with specific receptors in the human digestive system. The B.t proteins are quickly and easily digested by the gastric juice in the digestive system. Further the specific receptors are not found in other insect families and animal digestive system.

 B.t stick to soil particle and won’t mix with ground water. Hence water purity is not disturbed. In acid soil the B.t protein does not persist. The B.t proteins are rapidly degraded by the U.V rays of sunlight. The B.t protein persists in the soil up to 3 to 6 days thereafter it will be destroyed by soil microorganisms. There is no effect and difference in number and type of microorganisms in B.t and non B.t crop cultivated land.