6-oxo- 6H‒Dibenz[c, e] [1, 2] oxaphosphorin 6-alkyl derivative

Biodegradation in water: screening tests

Description of key information

This test assessed the inherent biodegradability of XP-7866 on micro-organisms in an aerobic aqueous medium by measuring the Biochemical Oxygen Demand (BOD). The test item was added directly into BOD bottle at an average level of32.8 mg/L (triplicate). Based on the calculation for BOD, the percentage biodegradation after treatment of 28 days averaged 0.9% (triplicate). The test item, XP-7866, did not exhibit a percentage biodegradation exceeding the pass level of 20% after 28 days and did not demonstrate inherent and primary biodegradability. The percentage degradation of aniline (reference item) reached 59.9% after the seventh day and 83.6% at the fourteenth day. According to the criterion of OECD Guideline for the Testing of Chemicals and SEPA Guidelines for the Testing of Chemicals, the test was considered valid.
Based on the grading criteria in the Guidelines for the Hazard Evaluation of New Chemical Substances, the test item, XP-7866 did not meet criteria for "inherent and primary biodegradability" under the described test conditions.

Key value for chemical safety assessment

Biodegradation in water:

under test conditions no biodegradation observed

Additional information

Two experimental studies are currently available to detremine the biodegradability of the test item, 6H-Dibenz [c,e] [1,2] oxaphosphorin, 6,6'( 1 ,2-ethanediyl) bis-6,6'-dioxide.

* Study report n°41101791 covers a ready biodegradability test following the OECD guideline 301B. While all the validation criteria were met, the test item attained 0% degradation after 28 days when looking at the CO2 evolution. With these results, it was concluded that the test item was not readily biodegradable.

* Suty report n° G1241A0020 lead to the conclusions that the substance was not inherent and primary biodegradable according the protocol designed by the OECD guideline 302c.