Alcohols, C16-18, reaction products with D-glucose

Biodegradation in water: screening tests

Description of key information

ready biodegradability (OECD 301B): 66% degradation after 28 days
ready biodegradability (OECD 301D): 69% degradation after 28 days (product containing 30% C16/18-APG and 70% C16/18 fatty alcohols)
ready biodegradability (OECD 301B): 82.4% degradation after 28 days (C16 fatty alcohol); 95.6% degradation after 28 days (C18 fatty alcohol)

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Additional information

One study investigating the biodegradation of D-Glucose, reaction products with alcohols C16-18 (even numbered) (excess) is available. In this key study, the ready biodegradability of the substance was tested according to OECD 301B and GLP (BASF, 2012). Activated sludge (domestic, non-adapted) was used as inoculum. The test substance was applied at an initial concentration of 20 mg/L (related to TOC). As a result, 66% of the test substance (mean of two replicates) was degraded after 28 days (CO2 evolution).

The test substance is a UVCB, typically characterized by different kinetic degradation steps. Therefore the 10 -day window is not applied and the test substance can be classified as „readily biodegradable“ as the required pass level of the test guideline OECD 301B (60 % CO2/ThCO2) was reached. This evaluation is in accordance with the OECD Guidelines for the testing of chemicals, laid down in the revised introduction to the OECD Guidelines for testing of chemicals, section 3; Part 1, Principles and strategies related to the testing of degradation of organic compounds, adopted 23 March 2006.

In another study on the biodegradation of D-Glucose, reaction products with alcohols C16 -18 (even numbered) (excess), the ready biodegradability of the substance (30% APG, 70% fatty alcohol) was tested according to OECD 301D and GLP (Henkel, 1993). Domestic sewage was used as inoculum. As a result, 69% of the test substance was degraded after 28 days (BSB). In conclusion, the substance can be considered as readily biodegradable based on OECD criteria.

Two other supporting studies investigated the ready biodegradability of C16 fatty alcohol (Weston Inc., 1993) and C18 fatty alcohol (Procter and Gamble, 2009), respectively, according to OECD 301B. Domestic activated sludge was used as inoculum. After 28 days, 82.4% and 95.6% of the test substance was degraded (CO2 evolution), confirming the ready biodegradability of the substance.

This read-across is in accordance with Regulation (EC) No. 1907/2006 Annex XI, 1.5 and justified in detail in the overall summary (IUCLID Chapter 5) and within the category justification attached in IUCLID Section 13. In this case of read-across, the best suited (highest degree of structural similarity, nearest physico-chemical properties) read-across substance was used for the assessment. Nevertheless, as it can be seen in the data matrix of the category justification in IUCLID Section 13 and the overall summary (IUCLID Chapter 5), all reliable data in the category support the hazard assessment of each category member by showing a consistent pattern of results.