Tall oil, reaction products with diethylenetriamine

Hydrolysis

Link to relevant study record(s)

Reference

Endpoint:

hydrolysis

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

It is considered appropriate to address the hydrolysis data requirement for DTO_DETA by read-across to an available study on AAI_TEPA.
AAI_TEPA is structurally related and of similar composition to AAI_DETA, a main component of DTO_DETA, with the only difference being the amine to which the fatty acid components are reacted with. AAI_TEPA contains a mixture of components, including monoamide, diamide and imidazoline (mono-, di and tri-condensate) structures. The substance therefore has common functional groups based on the amine, amide and imidazoline moieties, and is therefore considered structurally related to AAI_DETA.
For Rosins (the other main DTO_DETA component) no hydrolysis data is available. However, as Rosins are classified as readily biodegradable, information on hydrolysis is not required according to REACH Annex VIII. As such, it is judged that the hydrolysis data available for AAI_TEPA alone are sufficient to fulfil the DTO_DETA requirement for data on hydrolysis.

Reason / purpose for cross-reference:

read-across source

Preliminary study:

pH 4
Measured Conc. Conc. Conc. corrected
Sample Nominal T conc. T=0 T measured Extracted total Hydrolysis Hydrolysis
(µg/L) (hrs) (µg/L) (hrs) (µg/L) (µg/L) (µg/L) (%) (%)
M339 8827 0 5043 120 1,1 14,0 15,1 100,0 99,8
M361 8827 0 5276 120 92,3 2184,2 2276,5 98,2 74,2
M434 8827 0 4984 120 3786,5 59,4 3846,0 24,0 56,4
M452 8827 0 4648 120 4388,3 991,3 5379,6 5,6 39,1
M460 8827 0 5007 120 4123,6 37,8 4161,4 17,6 52,9


pH 7
Measured Conc. Conc. Conc. corrected
Sample Nominal T conc. T=0 T measured extracted total Hydrolysis Hydrolysis
(µg/L) (hrs) (µg/L) (hrs) (µg/L) (µg/L) (µg/L) (%) (%)
M339 8827 0 3820 120 0,0 0,3 0,3 100,0 100,0
M361 8827 0 7613 120 7,9 68,1 76,0 99,9 99,1
M434 8827 0 6294 120 372,4 11,9 384,3 94,1 95,6
M452 8827 0 6161 120 7438,1 3365,7 10803,8 -20,7 -22,4
M460 8827 0 6375 120 684,6 7,6 692,2 89,3 92,2


pH 9
Measured corrected
Sample Nominal T conc. T=0 T Measured Extracted Total Hydrolysis Hydrolysis
(µg/L) (hrs) (µg/L) (hrs) (µg/L) (µg/L) (µg/L) (%) (%)
M339 8827 0 4179 120 0,0 0,1 0,1 100,0 100,0
M361 8827 0 4893 120 29,5 15,0 44,5 99,4 99,5
M434 8827 0 5103 120 11,1 3,2 14,3 99,8 99,8
M452 8827 0 4246 120 60,9 73,8 134,7 98,6 98,5
M460 8827 0 4754 120 94,4 16,3 110,6 98,0 98,7

Test performance:

Hydrolysis of test substance was determined for 5 different molar masses: 339, 361 434, 452 and 460, all being part of the composition of the test substance. Thereby the absorbance of the test substance to the wall of the test vessel was determined and used for correction of the results

Transformation products:

not specified

No.:

#1

pH:

4

Temp.:

50 °C

Hydrolysis rate constant:

0.12 h-1

DT50:

5.7 h

St. dev.:

0.06

Type:

(pseudo-)first order (= half-life)

pH:

7

Temp.:

50 °C

Hydrolysis rate constant:

0.59 h-1

DT50:

1.2 h

St. dev.:

0.03

Type:

(pseudo-)first order (= half-life)

pH:

9

Temp.:

50 °C

Hydrolysis rate constant:

1.12 h-1

DT50:

0.6 h

St. dev.:

0.01

Type:

(pseudo-)first order (= half-life)

Details on results:

TEST CONDITIONS
- pH, sterility, temperature, and other experimental conditions maintained throughout the study: Yes
- Anomalies or problems encountered (if yes): no

MAJOR TRANSFORMATION PRODUCTS
At pH5:
- Range of maximum concentrations in % of the applied amount and day(s) of incubation when observed:
- Range of maximum concentrations in % of the applied amount at end of study period:
on the - the and -th day of incubation, respectively. At the end of the study period, the corresponding concentrations were - and -- % of the applied amount, respectively.

At pH7:
- Range of maximum concentrations in % of the applied amount and day(s) of incubation when observed:
- Range of maximum concentrations in % of the applied amount at end of study period:
on the - the and -th day of incubation, respectively. At the end of the study period, the corresponding concentrations were - and -- % of the applied amount, respectively.

At pH9:
- Range of maximum concentrations in % of the applied amount and day(s) of incubation when observed:
- Range of maximum concentrations in % of the applied amount at end of study period:
on the - the and -th day of incubation, respectively. At the end of the study period, the corresponding concentrations were - and -- % of the applied amount, respectively.

MINOR TRANSFORMATION PRODUCTS
Maximum concentrations in % of the applied amount
- at pH5:
- at pH7:
- at pH9:

MINERALISATION (distinguish between dark and irradiated samples)
- % of applied radioactivity present as CO2 at end of study:



PATHWAYS OF HYDROLYSIS
- Description of pathwayS:
- Figures of chemical structures attached: Yes

SUPPLEMENTARY EXPERIMENT (if any): RESULTS:

50 degrees

			Kobs	t1/2	AVG t1/2	St.dev. t1/2
		slope	(hrs^-1)	(hrs)	(hrs)	(hrs)
pH 4	series 1	-0,0522	0,12	5,77	5,7	0,06
	series 2	-0,0529	0,12	5,69
pH 7	series 1	-0,2498	0,58	1,21	1,2	0,03
	series 2	-0,2604	0,60	1,16
pH 9	series 1	-0,4905	1,13	0,61	0,6	0,01
	series 2	-0,4811	1,11	0,63

30 degrees

			Kobs	t1/2	AVG t1/2	St.dev. t1/2
		slope	(hrs^-1)	(hrs)	(hrs)	(hrs)
pH 4	series 1	-0.0064	0.01	46.89	47.5	0.89
	series 2	-0.0063	0.01	48.14
pH 7	series 1	-0.0543	0.12	5.55	5.6	0.12
	series 2	-0.0526	0.12	5.72
pH 9	series 1	-0.0543	0.12	5.55	5.6	0.05
	series 2	-0.0536	0.12	5.62

20 degrees

			Kobs	t1/2	AVG t1/2	St.dev. t1/2
		slope	(hrs^-1)	(hrs)	(hrs)	(hrs)
pH 4	series 1	-0.0008	0.002	358.89	371	17.0
	series 2	-0.0008	0.002	382.87
pH 7	series 1	-0.0192	0.04	15.70	16.3	0.79
	series 2	-0.0179	0.04	16.82
pH 9	series 1	-0.0167	0.04	17.97	19.5	2.12
	series 2	-0.0144	0.03	20.97

Validity criteria fulfilled:

yes

Conclusions:

The M339 component, representing the most condensed and main fraction of the test substance, showed hydrolysis at all pH values and at all temperatures, hydrolysis rate increased at higher temperatures and at higher pH values. The hydrolysis rate observed at a pH value of 7 and 9 was more or less equal.

Executive summary:

It is considered appropriate to address the hydrolysis data requirement for DTO_DETA by read-across to an available study on AAI_TEPA. AAI_TEPA is structurally related and of similar composition to AAI_DETA, a main component of DTO_DETA, with the only difference being the amine to which the fatty acid components are reacted with. AAI_TEPA contains a mixture of components, including monoamide, diamide and imidazoline (mono-, di and tri-condensate) structures. The substance therefore has common functional groups based on the amine, amide and imidazoline moieties, and is therefore considered structurally related to AAI_DETA. For Rosins (the other main DTO_DETA component) no hydrolysis data is available. However, as Rosins are classified as readily biodegradable, information on hydrolysis is not required according to REACH Annex VIII. As such, it is judged that the hydrolysis data available for AAI_TEPA alone are sufficient to fulfil the DTO_DETA requirement for data on hydrolysis.

The rate of hydrolysis of Tall oil, reaction products with tetraethylenepentamine (Redicote 404) was determined at 20°C, 30°C and 50°C and at the pH values of 4, 7 and 9 in agreement with OECD guideline 111.For the most condensed fraction of Redicote 404, TEPA tall oil diimidazolinewith molar mass M339, hydrolysis was observed at all tested pH values and temperatures. For TEPA tall oil diimidazolinethe half life(t_½) at a temperature of 25°C could be calculated for all testedpH valuesusing the Arrhenius relationship.

At pH 4 the half-lives (t_½) for the M339 component of Redicote 404 at a temperature of 20, 30 and 50°C were observed to be 371 hours, 47.5 hours and 5.7 hours respectively. Using the Arrhenius relationship a t_½at 25°C was calculated of 136 hours.

At pH 7 the half-lives (t_½) for the M339 component ofRedicote 404 at a temperature of 20, 30 and 50°C were observed to be 16.3 hours, 5.6 hours and 1.2 hours respectively. Using the Arrhenius relationship a t_½at 25°C was calculated of 9.6 hours.

At pH 9 the half-lives (t_½) for the M339 component ofRedicote 404at a temperature of 20, 30 and 50°C were observed to be 19.5 hours, 5.6 hours and 0.6 hours respectively. Using the Arrhenius relationship a t_½at 25°C was calculated of 10.3 hours.

For two intermediate hydrolysis products of Redicote 404 the half-lives have been determined. Using specified time periods for the half life determination of TEPA tall oil monoimidazoline (M434) and TEPA tall oil monoamide (M452) the following results were calculated.

		M434		M452
pH	Temp.	t½	Time period	t½	Time period
	°C		(hr.)		(hr.)
4	20	156 days	162.5-720	79 days	262-720
	30	39 days	6-144	44 days	6-144
	50	54.0 hr.	2-24	66.6 hr.	2.24
7	20	158 hr.	1-48.5	28 days	1-48.5
	30	Infinite	2-24	Infinite	2-24
	50	13.5 hr.	0.5-4	29.1 hr.	0.5-4
9	20	141 hr.	7-75	7487 days	7-75
	30	10.7 hr.	2-24	52.4 hr.	2-24
	50	5.8 hr.	0.5-3	Infinite	0.5-3

Description of key information

Imidazoline DETA

The 1/2 life of 28 days at 20 degrees for tall oil diethyenetriamine imidazoline is read across from the hydrolysis data from a similar substance i.e. a TEPA based imidazoline. The read across of this realistic worst case 1/2 life is considered justified also taking the biodegradation data into account.

Rosins

Rosins are readily biodegradable, therefore hydrolysis data are not needed.

The half life for DETA imidazoline is used as the key value for tall oil reaction products eith diethylenetriamine as a worst case.

Key value for chemical safety assessment

Half-life for hydrolysis:

28 d

at the temperature of:

20 °C

Additional information

Imidazoline DETA

The imidazoline ring(s) of tall oil diethylenetriamine imidazoline most likely undergo(es) hydrolysis under alkaline, neutral and acidic conditions (Akzo Nobel 2010; Watts, 1990). A hydrolysis rate of an imidazoline has been measured using a Tetraethylene pentamine based imidazoline. For this imidazoline a number of hydrolysis rates were measured as the imidazolines are in general a mixture of imidazolines and amides (non ring closed imidazolines). The tetraethylene pentamine based imidazoline contains even di-imidazolines. The shortest half-lifes of 16.3 h at 20°C were found under neutral conditions for the hydrolysis of the first imidazoline ring of the di-imidazoline. For the next step in the hydrolysis degradation route i.e. the hydrolysis of the amide by which the alkyl chain is detached a half-life of 158 h at 20°C was derived. This second reaction step is considered to be representative of the hydrolysis of the DETA based imidazoline as this is also a monoimidazoline. The next step in hydrolysis degradation route would be the opening of the second imidazoline and here a half life of 28 days at 20°C is derived. The order in which these last two hydrolysis reactions take place is not completely clear. When considering the biodegradation half-life of the DETA based imidazoline and the shape of the degradation curve it seems that a hydrolysis step is here a rate determining step. For read-across from the source chemical (TEPA based imidazoline) to the target chemical (DETA based imidazoline) the use of worst-case half-life of 28 days at 20°C is considered to be justified also taking the biodegradation half-life into account.

Rosins

No hydrolysis data are available for the rosins. However, as Rosins are classified as readily biodegradable, information on hydrolysis is not required.