cis-2-tert-butylcyclohexan-1-ol

Biodegradation in water: screening tests

Description of key information

The biotic degradation of Verdol was assessed in an aerobic aqueous medium in the Closed Bottle test performed according to OECD TG 301D in compliance with GLP. The test substance (2 mg/L) was exposed to river water, which was spiked to a mineral nutrient solution, dosed in closed bottles, and incubated in the dark at 21.9 to 22.9 °C for 60 days. The degradation of the test item was assessed by the measurement of oxygen consumption. According to the results of this study, the test item did cause a small reduction in the endogenous respiration at day 7. The "high" initial test substance concentration may therefore have been toxic to the inoculum and inhibited the biodegradation. A biodegradation percentage of 0% was achieved at day 28. The test substance should therefore not be classified as ready biodegradable. In the prolonged Closed Bottle test the biodegradation curve started to increase from day 42 and reached 13% at day 60. The lack of biodegradation in the Closed Bottle test does however not mean that the test substance is recalcitrant in nature because the stringency of the test procedures could account for the recalcitrance in the Closed Bottle test. The test is valid as shown by an endogenous respiration of 1.45 mg/L and by the total mineralization of the reference compound, sodium acetate. Sodium acetate was degraded by 86% of its theoretical oxygen demand after 14 days. Finally, the most important criterion was met by oxygen concentrations >0.5 mg/L in all bottles during the test period.

Key value for chemical safety assessment

Biodegradation in water:

not biodegradable

Type of water:

freshwater