2-methylaminoethanol

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

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 A (Ready Biodegradability: DOC Die Away Test)

GLP compliance:

no

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): activated sludge from laboratory wastewater plants treating municipal sewage
- Initial cell/biomass concentration: 30 mg/L of dry substance

Duration of test (contact time):

21 d

Initial conc.:

86 mg/L

Based on:

test mat.

Initial conc.:

20 mg/L

Based on:

DOC

Parameter followed for biodegradation estimation:

DOC removal

Reference substance:

benzoic acid, sodium salt

Parameter:

% degradation (DOC removal)

Value:

92 - 93

Sampling time:

21 d

Parameter:

% degradation (DOC removal)

Value:

84

Sampling time:

10 d

Parameter:

% degradation (DOC removal)

Value:

81

Sampling time:

7 d

Parameter:

% degradation (DOC removal)

Value:

76

Sampling time:

3 d

Parameter:

% degradation (DOC removal)

Value:

-5

Sampling time:

1 d

Details on results:

- lag phase: < 3 days
- 10-day window kept
- Degradation products: not measured

Elimination kinetics:

Day	Blank (mg/L)	Test substance		Physico-chemical control		Inhibition control		Reference substance
		(mg/L, DOC)	DOC decrease (%)	(mg/L, DOC)	DOC decrease (%)	(mg/L, DOC)	DOC decrease (%)	(mg/L, DOC)	DOC decrease (%)
0	2.4	20.5	0	22.9	6	40.0	0	19.4	0
1	0.6	19.7	-5	19.8	6	20.5	47	1.3	96
3	0.6	5.0	76	19.4	8	5.7	86	1.2	96
7	2.0	5.5	81	19.7	14	5.9	90	2.7	96
10	1.8	4.5	84	19.9	12	7.9	84
14	1.3	4.4	84	20.5	6	4.4	92
18	0.2	1.9	92	19.3	7	1.8	96
21	0.2	1.6	93	18.5	11	1.7	96

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

The test substance is readily biodegradable.

Executive summary:

A biodegradation test according to OECD guideline 301-A was performed.

After 21 days, 92 -93 % degradation were achieved. The 10 -day window was kept.

The test substance is readily biodegradable according to OECD criteria.

Description of key information

One valid experimental key result is available regarding biodegradation in fresh water for N-methylethanolamine (according to OECD 301A, BASF, 1993). After 21 days, 92 -93 % degradation were achieved. The 10 -day window was kept. The test substance is readily biodegradable according to OECD criteria.

The japanese biodegradation screening study (Japan Chemical Industry Ecology - Toxicology & Information Center; JETOC, 1992) was conducted according to OECD 301C. A mixed inoculum was used. After 28 days, degradation of 97 % (based on TOC removal) or 68 % (based on oxygen consumption) was achieved, respectively.

The test substance is readily biodegradable according to OECD criteria (BASF AG, 1993; MITI Japan, 1992).

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Type of water:

freshwater

Additional information

Three valid experimental data are available which demonstrate that N-Methylethanolamine is readily biodegradable according to OECD criteria. The OECD guideline 301 A was used with domestic sewage sludge, whereby 92 - 93 % degradation of test substance was measurable after 21 days. These measurements were based DOC removal (BASF AG, 1993). Thus the test substance is regarded as readily biodegradable. This result is confirmed by a test cited by the Japanese National Institute of Technology and Evalution. The test was conducted according to OECD guideline 301 C (MITI Japan, 1992). The exposure time was 28 days. 97 % degradation of N-Methylethanolamine was found concerning DOC removal and 68 % concerning oxygen consumption (BOD / ThOD).

In a study according to OECD 306 with marine water (Eide-Haugmo et al. 2012) ready biodegradability (76.6 % during 28 days) was observed.