1. The action or state of making something impure by exposure to or addition of a poisonous or polluting substance.
Usage: Usually used in plural or as a mass noun; Common in scientific, medical, and environmental contexts
2. Instances or types of contaminating substances or agents.
Usage: Plural form emphasizing multiple contaminants or separate contamination events

Examples

• The water supply showed several contaminations from industrial waste.
• Scientists tested the soil for contaminations before approving the construction site.
• Food contaminations can cause serious health problems if not detected early.
• The laboratory works to prevent contaminations in its sterile environment.
• Contaminations from bacteria were found in the medical samples.
• Air contaminations in the city have increased due to vehicle emissions.