Contaminants are any physical, biological, or chemical substances or energies found in the environment that can potentially cause adverse changes in air, water, soil, or food.

Some examples of contaminants include:

Physical contaminants:

* Dirt

*Dust

*Asbestos

*Lead

*Mercury

*Microplastics

*Radioactive waste

Biological contaminants:

* Bacteria

*Viruses

* Fungi

*Parasites

*Algae

*Pollen

Chemical contaminants:

* Pesticides

*Herbicides

*Fertilizers

*Industrial chemicals

*Household cleaners

*Personal care products

*Pharmaceuticals

*Heavy metals

* Volatile organic compounds

*Persistent organic pollutants