Impurities: meaning, definitions and examples

Used in scientific, technical, or industrial contexts to describe unwanted substances within a material or environment.

• The water was tested for impurities before being deemed safe for drinking.
• The presence of impurities in the metal can affect its strength.

Often used in environmental health and safety contexts to discuss harmful or unwanted substances that pollute or make something dirty.

• The food was recalled due to the presence of harmful contaminants.
• Regular cleaning helps keep contaminants out of the lab environment.

Mainly used in environmental contexts to describe substances that cause pollution, often having a negative impact on air, water, or soil quality.

• Factories must reduce their emission of pollutants to comply with environmental regulations.
• The river has been heavily contaminated with industrial pollutants.

Used generally to describe any foreign or extraneous substances that do not belong in a particular context or material.

• The inspectors found traces of foreign matter in the food products.
• Make sure to remove any foreign matter from the machinery before starting it.

Commonly used in scientific and industrial contexts to describe unwanted substances within a pure material. Often with a negative connotation, referring to materials that lower the quality or efficacy of the main substance.

• The metal must be refined to remove any impurities
• The water was tested for impurities before it was declared safe to drink

A broad term often used in scientific, medical, or industrial settings to describe any substances that are not originally part of the main material. This term can have a neutral or negative connotation depending on the context.

• The presence of foreign substances in the sample could skew the test results
• Allergies can often be caused by foreign substances entering the body

Used specifically in metallurgy to denote elements added to a metal to improve its properties, like strength, durability, or resistance to corrosion. Normally neutral or positive connotation, as these elements are deliberately added to enhance the material.

• Copper is one of the primary alloying elements used in brass
• Adding carbon to iron creates steel, which is much stronger due to the presence of the alloying elements