1-(N,N-bis(2-ethylhexyl)aminomethyl)-1,2,4-triazole

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:

April - May 1985

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

1981

Deviations:

yes

Remarks:

The volume of the test solution was reduced to 1.5 litre

GLP compliance:

no

Remarks:

but GLP like quality assurance

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge:
Bacteria collected from activated sludge of the sewage treatment plant of CH-4153 Reinach on 15/04/85. The preparation was carried out according to the method described in the guideline.

Duration of test (contact time):

28 d

Initial conc.:

10 mg/L

Based on:

test mat.

Initial conc.:

20 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

TEST CONDITIONS
- Composition of medium:The test medium was prepared according to the method described in the guideline.
- Test temperature: 22 + or - 2 degrees
- Aeration of dilution water: Approx. 50 ml/min free of carbon dioxide.

TEST SYSTEM
- Culturing apparatus: 2 liters flasks equipped with gas inlet and magnetic stirrer.
- Number of culture flasks/concentration: 1

SAMPLING
- Sampling frequency: day 6, 9, 13, 17, 20, 23, 27, 28

Reference substance:

aniline

Key result

Parameter:

% degradation (CO2 evolution)

Value:

5

Sampling time:

28 d

Remarks on result:

other: 20 mg/L test substance

Parameter:

% degradation (CO2 evolution)

Value:

9

Sampling time:

28 d

Remarks on result:

other: 10 mg/L test substance

Details on results:

The test item is not is not biodegradable in this test.
The biodegradation of the reference substances was calculated as 84% in 28 days

Interpretation of results:

not readily biodegradable

Conclusions:

The key study (Ciba, 1985) was performed according to OECD guideline no. 301B (1981). The relative degradation values calculated from the measurements performed during the test period (28 days) revealed no significant degradation of the test item. At 10 mg/L and 20 mg/L, 9 % and 5% were transformed to carbon dioxide, respectively. No toxicity control was included in this test, but test item is inhibitory to sludge bacteria (EC20 = 38 mg/L). In a supportive study (Ciba, 2005) the Chemical Oxygen Demand was determined. After an exposure of 2 h the amount of CO2 was very low, indicating no degradation of the test item. The substance EC 401-280-0 hydrolyses in contact with water immediately.

Therefore the hydrolysis products need to be considered.

Description of key information

Parent substance EC 401 -280-0

The key study (Ciba, 1985) was performed according to OECD guideline no. 301B (1981). The relative degradation values calculated from the measurements performed during the test period (28 days) revealed no significant degradation of the test item. At 10 mg/L and 20 mg/L, 9 % and 5% were transformed to carbon dioxide, respectively. No toxicity control was included in this test, but test item is inhibitory to sludge bacteria (EC20 = 38 mg/L).

In a supportive study (Ciba, 2005) the Chemical Oxygen Demand was determined. After an exposure of 2 h the amount of CO2 was very low, indicating no degradation of the test item. The substance EC 401-280-0 hydrolyses in contact with water immediately.

Therefore the hydrolysis products were also considered.

Hydrolysis products:

bis(2 -ethylhexyl)amine

Based on a weight-of-evidence approach,di-(2-ethylhexyl)amine is considered to be moderately biodegradable (not readily biodegradable according to OECD criteria). Two results from ready biodegradability tests are available, both performed under GLP conditions according to OECD 301B (CO2 Evolution Test), but indicating different biodegradation potential. In the most recent study and based on CO2/ThCO2, no biodegradation was observed, even after prolonged exposure of 60 days in total (BASF, 2012). Based on DOC removal, 83% of the substance was eliminated after 28 days, which is, however, interpreted to be likely due to adsorption to the sludge and/or test vessels. In the older study and based on CO2/ThCO2, the substance was degraded by ca. 30 % after 28 days and by ca. 50% after 39 days, respectively (BASF, 1997). The latter result is supported by a Zahn-Wellens-Test performed according to an older protocol, but similar to OECD 302B. The substance was easily eliminated from water (93% after 15 days, based on COD) (Hoechst, 1977). Furthermore, two QSAR results support the potential for biodegradation ofdi-(2-ethylhexyl)amine.With the CATALOGIC model simulating the MITI (I)-Test (OECD 301C), the degradation was estimated to reach ca. 39 % after 28 days (BASF, 2011). With the BIOWIN v4.10 model of the US EPA EPISuite (v4.10) programme, several of the seven BIOWIN sub-models predict the substance to be rapidly degradable within days or weeks. The overall prediction of ready biodegradability is "no", but on average the sub-models indicate that the substance is moderately biodegradable (BASF, 2013).

1H-1,2,4 -Triazole

Data on1H-1,2,4-triazole show that the substance is not readily biodegradable (ECHA disseminated REACH dossier, 2014)

Formaldehyde

Formaldehyde is expected to be readily biodegradable at low concentrations (Gerike 1990).

Key value for chemical safety assessment

Biodegradation in water:

not biodegradable