Summary
ISO 9888 determines the ultimate aerobic biodegradability of organic compounds in an aqueous medium by measuring dissolved organic carbon or chemical oxygen demand. The conditions of this test have a high inoculum concentration, allowing for the maximum value of biodegradation.
The ISO 9888 Testing Method
This process is very similar to the OECD 302B test. The sample material is mixed with sludge from a wastewater treatment plant and centrifuged. Over 28 days, the biodegradation process will remove dissolved organic carbon. The removal of the dissolved organic carbon (DOC) or chemical oxygen demand (COD) is measured and the degradation percentage is calculated as the ratio of dissolved organic carbon to the original dissolved organic carbon dosed, or the chemical oxygen demand removal to the original chemical oxygen demand dosed.
This test is appropriate for use on highly soluble (>50 mg DOC/L), non-volatile, and non-absorbing substances.
If You Are Interested in ISO 9888, Contact Aropha for More Information
For streamlined, accurate, and efficient biodegradability testing, turn to Aropha. From plastics to lubricants to personal care products, we have the testing capabilities needed to determine the biodegradability, compostability, or ecotoxicity of your products. Our team combines digital twin simulations with lab biodegradability testing to serve your projects from research to commercialization as efficiently as possible.
Not only can we test your products, but we can provide you with GLP-compliant documentation necessary for certain eco-labels and regulatory agencies.
Contact our team today to get started!
ISO 9888 Requirement and Applicability
Different testing methods are applicable for materials with different properties. Below is a summary of the applicability of ISO 9888. Please check our Method Selection Guide to select the most appropriate method for your materials. You can also find the applicability for many other methods in our Resource Center.| Test | Analytical method | Sample info required * | Poorly soluble | Volatile | Adsorbing |
|---|---|---|---|---|---|
| ISO 9888 (Zahn-Wellens) | DOC or COD | Organic carbon content * or COD * | +/- | - | - |
*“Sample info required” is the information needed to calculate the biodegradation percentages. This must be available for a selected method.
*“Organic carbon content” is the ratio of the organic carbon weight to the weight of the sample. It can be calculated by the sample formula (e.g., acetic acid C2H4O2, organic carbon content is 12*2/(12*2+1*4+16*2)=40%). Try our Online C% Calculator. If the formula is unknown, we can send the sample out to a third party lab for you for analysis (normally $110 with a 10-day turnaround time).
*“COD”: we provide COD analysis at Aropha.
Pricing
$899/sample for High-Throughput Screening$1599/sample for Biodegradability Certification