Biodegradability Testing


"Readily" or "Ultimate" Biodegradable Testing OECD, ASTM, & ISO Testing Standards and more**…

RespirTek™, an ISO/IEC 17025:2005 accredited laboratory, can help you determine with confidence if your product as a whole or its individual components meet the requirements for ASTM, EPA, ISO, or OECD definitions of biodegradability, by conducting tests such as the following:

RespirTek’s vast experience in the global biodegradability testing market can assist you in navigating the various test methods as well as their applicability to your product(s) and/or marketing efforts.

With increasing global environmental awareness, the importance of producing biodegradable plastics, papers, coatings, and other consumer materials whether of a solid or liquid nature is driving manufacturers to be ahead of the curve and gain market share for the future. However, uncertainty in establishing confident relationships with laboratories conducting biodegradability assessments plagues those not immersed daily in this specialty testing. Whether you are interested in the biodegradability of a plastic material, shampoo, or wet-wipe, RespirTek can guide you seamlessly through the process of method selection, while welcoming any questions regarding the application of the results.

RespirTek, as a consulting laboratory for over 10 years, has certified a significant number of commercially-sold materials as biodegradable using standard test methods for Ready Biodegradability or Ultimate Biodegradability. Our team of customer service representatives, scientists, and engineers work tirelessly to provide the highest quality results, backed by our ISO/IEC 17025:2005 certification, while ensuring superior customer satisfaction from initial contact to project closure.

OCED Biodegradability Tests


OECD 301 Testing – Ready/Ultimate Biodegradability (Includes OECD 310)

The OECD 301 series of tests allows for direct, explicit certification of a material’s biodegradability. The methods establish threshold criteria for the direct classification and marketing of materials under the terms of Ready or Ultimate Biodegradability. A material is considered Readily Biodegradable if 60% (or 70% for some tests) of the organic carbon in the material is converted to CO2 within a 10 day window as well as a full 28 day test period. The 10 day window is defined as beginning when 10% of the organic carbon has been converted to CO2 and lasts for 10 days (but before 28 full days of the test). A material is considered Ultimately Biodegradable (under the subclassification of Inherent Biodegradability) if 60% (or 70% for some tests) of the organic carbon in the material is converted to CO2 over the duration of the test. The test can be extended beyond 28 days in this case.

OECD 311 – Anaerobic Biodegradability of Organic Compounds in Digested Sludge

The OECD 311 methodology is used to assess the biodegradability of organic chemicals in anaerobic conditions. This test method simulates conditions similar to that in an anaerobic digester, which is a biological reactor typically used to digest sewage sludge after water treatment. Residual chemicals that are not degraded in standard aerobic treatment basins will often end up in anaerobic digesters as a last treatment option prior to discharge to the environment.

ASTM Biodegradability Tests


ASTM E1720 - Standard Test Method for Determining Ready, Ultimate, Biodegradability of Organic Chemicals in a Sealed Vessel CO2 Production Test

(WITHDRAWN NO REPLACEMENT)

ASTM D5210 - Standard Test Method for Determining the Anaerobic Biodegradation of Plastic Materials in the Presence of Municipal Sewage Sludge

The ASTM D5210 test method is very similar to OECD 311 and is used to assess the biodegradability of organic chemicals in anaerobic conditions. This test method simulates conditions similar to that in an anaerobic digester, which is a biological reactor typically used to digest sewage sludge after water treatment. Residual chemicals that are not degraded in standard aerobic treatment basins will often end up in anaerobic digesters as a last treatment option prior to discharge to the environment.

ASTM D5271 - Standard Test Method for Determining the Aerobic Biodegradation of Plastic Materials in an Activated-Sludge-Wastewater-Treatment System

The ASTM D5271 test method evaluates the aerobic biodegradation of plastic materials in activated sludge wastewater treatment systems. The duration of this test method is a maximum of 6 months. No explicit thresholds or classifications are permitted based on method language for certification purposes. The method is used to index the biodegradability of plastic materials relative to controls that are known to persist (not biodegrade). The standard was withdrawn in 2011.

ASTM D5338 - Standard Test Method for Determining Aerobic Biodegradation of Plastic Materials Under Controlled Composting Conditions. Incorporating Thermophilic Temperatures

The ASTM D5338 test method evaluates the biodegradation of plastic materials under controlled composting conditions. Controlled composting conditions are considered those conditions where oxygen, temperature, moisture, and pH levels of the compost are maintained at optimal levels. Commercial composting facilities are the relevant disposal compartment for materials that undergo assessments based on this type of test method. The duration of the test can be up to 180 days. No explicit thresholds or classifications are permitted based on method language for certification purposes.

ASTM D5864 - Standard Test Method for Determining Aerobic Aquatic Biodegradation of Lubricants or Their Components

The ASTM D5864 test method evaluates the aerobic biodegradation of lubricants or lubricant components in aqueous solutions with low concentrations of inoculums. The test objective is to simulate the environmental exposure of lubricants during release into non-wastewater treatment environments. A variety of inoculums sources from soil, surface water, and other similar nature is used. The test duration is 28 days or until a plateau in biodegradation is reached. No explicit thresholds or classifications are permitted based on method language for certification purposes.

ASTM D5988 - Standard Test Method for Determining Aerobic Biodegradation in Soil of Plastic Materials or Residual Plastic Materials After Composting

The ASTM D5988 test method evaluates the aerobic biodegradation of plastic materials in soil. The method can be used as a complementary method to ASTM D5338 in an effort to determine if residual material not degraded in the timeframe of D5338 can be further degraded after the compost is integrated into the soil environment. The maximum duration of the test is 6 months. No explicit thresholds or classifications are permitted based on method language for certification purposes.

ASTM D6400 - Standard Specification for Compostable Plastics

ASTM D6400 is not a test method but instead provides specifications to follow in order to make claims of “Compostable.” The specification involves testing the plastic material for (1) disintegration (2) biodegradation and (3) ecological impacts. A heavy metals analysis is also conducted to ensure the material is within standard limits provided for healthy composting. The disintegration testing and biodegradation testing are conducted concurrently. Disintegration is evaluated by sieving the compost-plastic mixture after a set time to measure the amount of plastic that passes through the sieve. Biodegradation is a measure of the conversion of organic carbon to CO2 under aerobic, composting conditions. ASTM D5338 is the test method used to evaluate the biodegradation. Ecological impacts are evaluated via OECD 208, which is a plant growth test. Residual compost is mixed with soil in specified proportions to evaluate the ability of standard plant-types to thrive in the compost residues. This specification allows for the classification of a plastic material of Compostable if all threshold criteria are met.

ASTM D6954 - Standard Guide for Exposing and Testing Plastics that Degrade in the Environment by a Combination of Oxidation and Biodegradation

The ASTM D6954 test method evaluates the oxo-biodegradability of plastic materials in the environment. Ecological assessments are conducted to establish no harmful effects on aquatic and soil organisms as well as seed germination and plant growth. Oxo-biodegradation is a new technology that simulates oxidation via thermal or photo-oxidation sources. Following, a biodegradation assessment is made, and finally the matrix reside is subject to ecological testing to ensure no adverse affects to the environment. No explicit thresholds or classifications are permitted based on method language for certification purposes.

ISO Biodegradability Tests


ISO 9439 - Evaluation of ultimate aerobic biodegradability of organic compounds in aqueous medium -- Carbon dioxide evolution test

The ISO 9439 test method evaluates the aerobic biodegradability of organic compounds in an aqueous medium using common sewage sludge found in wastewater treatment plants. This test method is similar in setup to OECD 301B. Biodegradation is measured as the percentage of organic carbon converted to CO2. The duration of the test is 28 days. No explicit thresholds or classifications are permitted based on method language for certification purposes.

ISO 14593 - Evaluation of ultimate aerobic biodegradability of organic compounds in aqueous medium -- Method by analysis of inorganic carbon in sealed vessels (CO2 headspace test)

The ISO 14593 test method evaluates the aerobic biodegradability of organic compounds in aqueous medium using common sewage sludge found in wastewater treatment plants. The test is conducted in sealed vessels similar to ASTM E1720 and OECD 310. Biodegradation is measured as the percentage of organic carbon converted to CO2. The test duration is 28 days. No explicit thresholds or classifications are permitted based on method language for certification purposes.

ISO 14852 - Determination of the ultimate aerobic biodegradability of plastic materials in an aqueous medium -- Method by analysis of evolved carbon dioxide

The ISO 14852 test method evaluates the ultimate aerobic biodegradability of plastic materials in aqueous medium with the sources of inoculums for the test varying and depending on the final disposal. Compost, soil, or sewage sludge can be used. Biodegradation is measured as the percentage of organic carbon converted to CO2. The test duration cannot exceed 6 months. No explicit thresholds or classifications are permitted based on method language for certification purposes.

ISO 14855 - Determination of the ultimate aerobic biodegradability of plastic materials under controlled composting conditions -- Method by analysis of evolved carbon dioxide

The ISO 14855 test method evaluates the ultimate aerobic biodegradability of plastic materials under controlled composting conditions. This test method is nearly identical to ASTM D5338 in execution. Controlled composting conditions are maintained throughout the test, including oxygen and moisture content, temperature, and pH. Biodegradation is measured as the percentage of organic carbon converted to CO2. The test duration is 180 days. No explicit thresholds or classifications are permitted based on method language for certification purposes.

ISO 15985 - Plastics -- Determination of the ultimate anaerobic biodegradation and disintegration under high-solids anaerobic-digestion conditions -- Method by analysis of released biogas

The ISO 15985 test method evaluates the ultimate anaerobic biodegradation of plastic materials under high-solids anaerobic digestion conditions. This test method is very similar to ASTM D5511 in that anaerobic conditions with high solids content are used. Biodegradation is measured as the percentage of organic carbon converted to CO2 and CH4 biogas. The duration of the test can be extended until no significant biodegradation is observed. No explicit thresholds or classifications are permitted based on method language for certification purposes.