Butyl ricinoleate

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

January 12 2018 to February 17 2018

Reliability:

1 (reliable without restriction)

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test)

Version / remarks:

1992

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.4-C (Determination of the "Ready" Biodegradability - Carbon Dioxide Evolution Test)

Version / remarks:

Directive 92/69/EEC Annex V

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

The test substance is listed as Butyl Ricinoleate (CAS 151-13-3). The test substance consists of a liquid and was obtained from the Sponsor, Vertellus Holdings LLC and stored at ambient conditions.

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Details on inoculum:

Activated sludge was collected from the Easton Wastewater Treatment Facility, Easton, Maryland on January 12, 2018. The Easton facility treats predominantly residential wastes. The sludge was sieved using a 2-mm screen, adjusted to approximately 1,000 mg total suspended solids/L with mineral media and then aerated at 20 ± 3˚C for approximately 48 hours prior to use.

Duration of test (contact time):

28 d

Initial conc.:

10 mg/L

Based on:

TOC

Initial conc.:

0.04 other: g

Based on:

test mat.

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

The test contained a blank control group, a reference group, a treatment group and a single toxicity control. Each group contained three replicate test chambers. The control group was used to measure the background CO2 production of the inoculum and was not dosed with a carbon source. The reference group chambers were used to check the viability of the inoculum and were dosed with sodium benzoate, a substance known to be biodegradable, at a nominal concentration of 10 mg C/L. The treatment group chambers were used to evaluate the test substance at a nominal concentration of 10 mg C/L. The toxicity control was used to evaluate toxicity of the test substance to the inoculum and was dosed with both the reference (10 mg C/L) and test (10 mg C/L) substances.

Reference substance:

benzoic acid, sodium salt

Key result

Parameter:

% degradation (CO2 evolution)

Value:

90.2

Sampling time:

28 d

Validity criteria fulfilled:

yes

Remarks:

IC content <5% (protocol ≤ 5%); CO2 emitted by controls < 40 mg/L (protocol <70 mg/L); difference replicates less than 20% (protocol ≤20 %); degradation positive control >60% at 6 d (protocol ≤14 d); degradation toxicity d 3, >25% (protocol ≥25%).

Interpretation of results:

readily biodegradable

Conclusions:

The test substance is considered as “readily biodegradable”. The test substance reached 90.2% biodegradation after 28 d, meeting the 10-day window.

Description of key information

The key study was a CO₂ evolution test conducted in accordance with OECD Guideline 301B. The substance was found to be readily biodegradable in a test conducted in accordance with OECD Guideline 301B. The biodegradation was reported as 90.2% after 28 days, meeting the 10-day window. 

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Type of water:

freshwater