Registration Dossier

Environmental fate & pathways

Biodegradation in water: screening tests

Currently viewing:

Administrative data

Link to relevant study record(s)

Reference
Endpoint:
biodegradation in water: ready biodegradability
Type of information:
other: experimental study on hydrolysis product n-Butanol
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
study well documented, meets generally accepted scientific principles, acceptable for assessment
Principles of method if other than guideline:
BOD (Standard Methods for the Examination of Water and Wastewater. 1971. 13th Ed. American Public Health Association, New York, NY)
GLP compliance:
no
Oxygen conditions:
aerobic
Inoculum or test system:
sewage, domestic, non-adapted
Duration of test (contact time):
20 d
Initial conc.:
3 mg/L
Based on:
test mat.
Details on study design:
Settled domestic wastewater was filtered through glass wool and added (3 mL/bottle) to clean 300 mL BOD bottles. Aerated dilution water containing minerals specified in the method were added to the bottles along with buffer. Test chemical was added to the bottles. Potential oxygen demand was 3 to 30 mg/L over 20 days. Dissolved oxygen was measured on days 0, 5, 10, 20 using a dissolved O2 meter. When oxygen decreased to <4 mg/L in any bottle, it was reaerated. Concentration: 3, 7 and 10 mg/L (at least two are represented)
Parameter:
% degradation (O2 consumption)
Value:
68
Sampling time:
5 d
Parameter:
% degradation (O2 consumption)
Value:
87
Sampling time:
10 d
Parameter:
% degradation (O2 consumption)
Value:
92
Sampling time:
15 d
Key result
Parameter:
% degradation (O2 consumption)
Value:
92
Sampling time:
20 d
Validity criteria fulfilled:
not specified
Interpretation of results:
readily biodegradable

Description of key information

Tributyl borate is rapidly hydrolyzed to Boric acid and n-Butanol in the presence of water (18.3 sec at 21°C).

Boric acid is an inorganic compound and not degradable and thus, not subject to biodegradation.

Reliable data of the hydrolysis product n-Butanol are used to address the endpoint, which is entirely appropriate to draw conclusions on the biodegradation of Tributyl borate: n-Butanol is readily biodegradable (according to OECD criteria).

Key value for chemical safety assessment

Biodegradation in water:
readily biodegradable

Additional information

[Type of water: freshwater]