Little Known Ways To Avoid Poisonous Mushrooms By: David H Urmann | - Poisonous mushrooms can be those in decomposing stages and are infested with bacteria, fungi or with harsh chemicals. It is also called toadstools. Mushroom poisoning refers to the ingestion of toxic substances present in mushrooms. People should consider some of the little known ways to avoid poisonous mushrooms to enjoy different edible types in our cuisine.