Poisonous substances are a common issue in today's world. They cause countless health problems for people and the environment. In order to properly address the issue, it is important to understand the various synonyms for the term "poisonous substances". Some of these synonyms include toxic, venomous, lethal, noxious, harmful and dangerous. These words all describe substances that have the potential to cause harm to a person or the environment. Knowing these synonyms can help people understand how to properly deal with these substances, avoid them or safely dispose of them. It is important that individuals take caution when dealing with poisonous substances to avoid causing harm to themselves or those around them.