Not poisonous.

The bitter taste of mustard greens does not mean they are poisonous. In fact, the bitter taste of mustard greens in most biological common sense represents danger, but this does not mean that this vegetable is poisonous. This bitter taste is caused by the 11 volatile isocyanates contained in mustard. After human metabolism, it will generate isocyanate compounds. This substance has a bitter taste, but mustard itself also contains a lot of vitamins, so it tastes good when eaten. It will not cause harm to the body and can ensure the health of the gastrointestinal tract.