Oxidisable substances testing for assessing water quality

Laboratories of Eurofins Water Hygiene Testing are able to test for the presence of oxidisable substances in water across a wide variety of applications and sample matrix types.

Why oxidisable substances testing matters

Testing for oxidisable substances provides valuable insight into the organic content and pollution levels in natural, potable, and treated water. Key parameters in this category include:

  • The Permanganate Index
  • Dissolved Oxygen (DO)
  • Biochemical Oxygen Demand (BOD)
  • Chemical Oxygen Demand (COD)
  • Total and Dissolved Organic Carbon (TOC, DOC),
  • Total and Dissolved Inorganic Carbon (TIC, DIC)

These tests are essential for evaluating source water quality, discharge compliance, and the performance of water and wastewater treatment processes.

Monitoring organic loading, source quality and treatment performance

Understanding the oxidisable fraction of water is critical for assessing both natural and anthropogenic impacts. High oxygen demand indicates the presence of biodegradable or chemically reactive organics that can deplete dissolved oxygen, harm aquatic life, and compromise treatment performance.

Regular monitoring helps identify contamination sources, verify treatment efficiency, and demonstrate compliance with environmental or drinking water regulations:

  • Permanganate Index – measures the amount of organic matter oxidised under standard conditions and is required under the Water Supply (Water Quality) Regulations for drinking water
  • Dissolved Oxygen (DO); indicates the oxygen available for aquatic organisms and reflects system health
  • Biochemical Oxygen Demand (BOD); measures the oxygen consumed by microorganisms over five days and is key for environmental discharge consents.
  • Chemical Oxygen Demand (COD); quantifies oxygen demand from both biodegradable and non-biodegradable organics, supporting wastewater and effluent assessment
  • Total and Dissolved Organic Carbon (TOC, DOC); measure organic carbon content, indicating overall purity and treatment effectiveness
  • Total and Dissolved Inorganic Carbon (TIC, DIC); represent carbonate species and are important for understanding buffering capacity and system stability

Testing and methods

Eurofins water hygiene testing offers comprehensive analysis of oxidisable substances across surface water, groundwater, drinking water, and treated effluent. Testing is performed using validated methods including spectrophotometry, respirometry, and advanced TOC/DOC analysis. Typical turnaround times are five to seven working days depending on the test type and any incubation or stabilisation required. Testing is conducted in UKAS accredited laboratories with matrix-dependent accreditation. For extended analyte coverage, we work with approved subcontractors, including Eurofins European partners.

Who we serve

  • Environmental and water quality consultants
  • Water utilities
  • Local authorities
  • Industrial and manufacturing sites
  • Facilities and compliance teams managing discharge consents or treatment plants

Whether for routine monitoring, compliance reporting, or pollution incident investigation, our accredited testing provides dependable results.

Why choose Eurofins Water Hygiene Testing

  • UKAS accredited testing for Permanganate Index, COD, and BOD
  • Suitable for raw, drinking, treated, and environmental water
  • Supports Water Framework Directive, Water Quality Regulations, and permit compliance
  • Reliable turnaround with clear, accessible reporting
  • Nationwide logistics network ensuring secure and rapid sample transport

UK-wide drop-off facilities

Eurofins UK clients benefit from our extensive and free to use logistics and sample drop-off network with over 60 drop-off locations.

Sample bottles

To ensure that we are able to test your water chemistry samples please submit them in appropriate sample bottles. 

Get in touch

Would you like to find out more about our water hygiene testing and compliance services? Contact Eurofins Water Hygiene Testing UK today by submitting an enquiry form or calling +44 (0) 845 604 6740.

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