Biodegradability analysis – OECD 301 test

Biodegradability analysis according to the OECD 301 test is a reference method for assessing the readily biodegradable nature of a dissolved organic substance. This analysis is essential for determining the environmental behavior of chemicals, biocides, surfactants, or water-soluble natural substances.

Recognized under the REACH, CLP or Biocidal Products Regulation (BPR), the OECD 301 test demonstrates the rapid degradation of a molecule, a key step for environmental labeling, marketing authorization or the selection of eco-responsible ingredients.

OECD 301 Test Objective

The OECD 301 test aims to measure whether a substance can be rapidly biodegraded (>60% in 28 days) by microorganisms present in the environment. It allows for:

• Evaluate the intrinsic biodegradability of a compound
• Compare alternative substances or formulations
• Justify the classification of an ingredient in a safety data sheet (SDS)
• Meeting the requirements of regulatory dossiers (REACH, BPR, etc.)

Methodology

The substance is added to a microbial inoculum (activated sludge, wastewater, etc.), incubated for 28 days under standardized conditions.

Depending on the OECD 301 variant used, biodegradation is followed by:

• OECD 301B: CO₂ released (evolved CO₂ test)
• OECD 301D: Measurement of BOD (biological oxygen demand)
• OECD 301F: COD – BOD – organic residues
• OECD 301C/E: Specific tests less used

The substance is considered rapidly biodegradable if it reaches 60% degradation (according to the chosen indicator) within 10 days from the moment 10% degradation is observed.

Associated analytical techniques

• Indirect calorimetry (CO₂)
• BOD5 / BOD28 Measurement
• HPLC or UV chromatography for residual concentration
• COD measurement as a complement

Affected matrices

• Water-soluble biocides
• Household and industrial products
• Surfactants
• Natural substances (plants, extracts)
• Chemical or cosmetic raw materials

Industrial applications

• Environmental impact assessment
• Validation of “biodegradable” labeling
• Selection of ingredients for eco-friendly formulations
• Integration into regulatory registration files

Why choose YesWeLab?

YesWeLab connects you to laboratories specializing in OECD 301 analysis, accredited to ISO 17025, capable of choosing the variant best suited to your matrix.

Our team assists you in selecting the test, preparing regulatory files, and interpreting the results.