Amines, (2-ethylhexyl)(hydrogenated tallow alkyl)methyl

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

used as read across

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Inoculum or test system:

activated sludge, non-adapted

Duration of test (contact time):

44 d

Parameter:

% degradation (CO2 evolution)

Value:

47.9

Sampling time:

28 d

Parameter:

% degradation (CO2 evolution)

Value:

61.1

Sampling time:

44 d

Positive control (sodium benzoate) degraded 84% within 6 days.

Validity criteria fulfilled:

yes

Interpretation of results:

inherently biodegradable, fulfilling specific criteria

Reference 2

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

26 May to 06 July 2016

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other:

Justification for type of information:

This study was conducted in a Chinese laboratory under GLP. However, this study was not directly monitored and, therefore, additional information is provided on an analog substance to confirm that it is readily biodegradable.

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, adapted

Duration of test (contact time):

28 d

Initial conc.:

25 mg/L

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

EST CONDITIONS
- Composition of medium: filtered sewage pre-conditioned by aerating secondary effluent for 7 days
- Test temperature: 22 +/- 2 °C
- pH: not stated
- Continuous darkness: yes


SAMPLING
- Sampling frequency: day 1, 3, 6, 8, 11, 14, 16, 18, 21, 24, and 28

Reference substance:

benzoic acid, sodium salt

Key result

Parameter:

% degradation (CO2 evolution)

Value:

64.9

Sampling time:

29 d

Details on results:

The test substance met the 10-day window and had the following cumulative degradation at days 1, 3, 6, 8, 11, 14, 16, 18, 21, 24, 28, and 29 days: 0.5, 1.7, 2.0, 4.8, 10.2, 22.0, 37.9, 50.5, 62.3, 64.4, 64.4, 64.9.

Results with reference substance:

Degradation of the reference substance was 87.9% after 14 days meeting validitation requirements.

Degradation of the toxicity control was 39.7% after 14 days meeting validation requirements.

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

This substance is readily biodegradable as it degraded 64.9% after 28 days and met the 10-day window.

Reference 3

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

Used an emulsifier to solubilize test material. Read across

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 301 D (Ready Biodegradability: Closed Bottle Test)

GLP compliance:

no

Inoculum or test system:

activated sludge, domestic, adapted

Duration of test (contact time):

6 wk

Key result

Parameter:

% degradation (DOC removal)

Value:

86

Sampling time:

14 d

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Description of key information

The notified substance was readily biodegradable in the key study as it reached 64.9% degradation after 28 days, including meeting the 10-day window. This study was conducted in a Chinese laboratory under GLP. However, this study was not directly monitored and, therefore, two supporting studies are provided on an analog substance, CAS 61788-63-4, to confirm that the material is readily biodegradable.

 

CAS 61788-63-4 was readily biodegradable in a well conducted OECD 301D study (Balk, 1987). This study is Klimisch coded as 2 as it used an emulsifier due to the low water solubility of the test material. A second study with CAS 61788-63-4 (OECD 301B, Battelle, 1992) resulted in rapid but not readily biodegradation. The US EPA screening-level hazard characterization on fatty nitrogen derived amines (September, 2010) typically found these materials to be readily biodegradable with low (P1) persistence; this includes the application of the OECD 301D (Balk, 1987) study to the category as it was deemed of acceptable quality.

 

CAS 61788-63-4 has a larger molecular weight due to one alkyl chain being longer (C14-18 instead of 2-ethylhexyl). In the case of biodegradation, read across from a larger molecular weight analog with longer alkyl chain lengths is appropriate as the smaller molecular weight analog will degrade more rapidly. Therefore, the weight of evidence supports the application of the key study to conclude that this material is readily biodegradable.

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable