Lab Q

Water Contamination: Causes and Impacts

Water, known as the universal solvent, is essential for life. However, it is rare to find water in its purest form in nature, as it undergoes changes driven by physical and chemical factor-. Contamination can occur at the water source or during distribution, introducing impurities such as germs, dissolved ions, and other substances that can have adverse effects. Understanding the importance of water quality, especially in laboratory and healthcare settings, is crucial to ensure accurate results and prevent potential harm.

Impurities in Water and Their Effects

Various impurities can significantly impact water quality, affecting laboratory procedures and scientific experiments. These impurities can be broadly classified into three categories: inorganic ions, organics, particulates and colloids, and bacteria and their by-products.

  • Inorganic Ions

Inorganic ions, including cations like sodium, calcium, magnesium, iron, and anions such as bicarbonate, chloride, and sulfate, form a major part of water impurities. Even in trace amounts, these ions can act as catalysts, influencing both organic and biochemical reactions. Dissolved inorganic impurities may cause ionic instability during experiments, disrupting protein-protein interactions and altering chemical reaction rates.

  • Organics

Dissolved organic molecules in tap water, often of biological origin, can originate from sources like decaying plants, PVC pipe leaks, pesticides, herbicides, domestic waste, and industrial waste. Compounds like humic acids, tannins, and lignin are common organic impurities. In laboratory settings, dissolved organics can adversely affect biological experiments such as cell culture and analytical techniques. They decrease the sensitivity of high-performance liquid chromatography and may introduce bacteria that release endotoxins and nucleases, disrupting molecular biology tests involving DNA and RNA.

  • Particulates and Colloids

Natural water contains soft particulates (e.g., vegetal debris) and hard particulates (e.g., sand, rock), as well as colloids that can interfere with instrument operation. These particles can impact the accuracy and reliability of various measurements and analyses.

  • Bacteria and Their By-Products

Bacterial contamination is common in surface water sources. Bacteria themselves or their by-products, such as pyrogens, nucleases, or alkaline phosphatase, can cause issues in laboratory experiments. These contaminants can directly affect results or interfere with specific biological processes, rendering inaccurate or unreliable data.

  • Gasses

Dissolved gasses, such as nitrogen, oxygen, and carbon dioxide, are found in natural water. The concentration of oxygen can influence biochemical reactions, while nitrogen bubbles can disrupt processes like particulate counting or spectrophotometric measurements. Dissolved carbon dioxide can affect the pH resistivity of water and lead to errors in signals and detectors of certain analyzers.


To avoid or minimize the inconveniences caused by water impurities, it is essential to install high-purity water purification system for lab. Understanding the different types of contaminants and their potential effects allows researchers and healthcare professionals to take appropriate measures to ensure reliable results and maintain the integrity of their experiments and diagnostic procedures. By prioritizing water quality and utilizing pure and ultrapure water for laboratories, we can improve the accuracy and safety of scientific applications across various disciplines.