Reaction products of C18 (unsaturated) fatty acids and dimethyl sulfate and triethanolamine

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

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

Adequacy of study:

key study

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
This read-across is based on the hypothesis that source and target substances have similar (eco)toxicological properties because
• they share structural similarities with common functional groups: One quaternised ethanolamine moiety, one to three, mainly two ester groups with a typical UVCB distribution with long-chain fatty acids of natural origin. The molecular structure is almost identical.
• they are manufactured from similar resp. identical precursors (triethanolamine, long-chain fatty acids, dimethyl sulphate) under similar conditions. Therefore, common breakdown products via physical and biological processes, which result in structurally similar chemicals are evident
• A constant pattern in the changing of the potency of the properties across the TEA-Esterquats by chain-length and the grade of esterification is not observed, because the fatty acid chain-length distribution is too narrow and similar and the distribution of mono-, di-, and tri-esters is identical. Some variation caused by variation in C=C double bonds may occur and will be discussed at the relevant endpoint.

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
See justification for read-across attached to chapter 13 of this IUCLID file.

3. ANALOGUE APPROACH JUSTIFICATION
See justification for read-across attached to chapter 13 of this IUCLID file.

4. DATA MATRIX
See justification for read-across attached to chapter 13 of this IUCLID file.

Reason / purpose for cross-reference:

read-across: supporting information

Reason / purpose for cross-reference:

read-across source

Test organisms (species):

Daphnia magna

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Key result

Duration:

21 d

Dose descriptor:

EC10

Effect conc.:

0.346 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

reproduction

Remarks on result:

other: 95% ci: 0.150 – 0.797 mg/L

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

0.268 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

reproduction

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

0.984 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks:

adult mortality

Conclusions:

The effects on reproduction were evaluated based on the reproduction per introduced parent animal, since this parameter is the ecologically most relevant response variable and is required by OECD test guideline 211 (2012), when a significant trend in mortality is detected.
The overall effect threshold for effects of the test item under the test conditions was 0.268 mg/L (NOEC) and 0.984 mg/L (LOEC) based on the time weighted mean measured concentrations of the test item. The EC50 for reproduction was determined to be 0.792 (0.303 – 2.118) mg/L based on the time weighted mean measured concentrations of the test item.
The overall effect threshold for effects of the test item under the test conditions was 0.658 mg/L (NOEC) and 2.08 mg/L (LOEC) based on the nominal concentration of the test item .

Description of key information

21 d EC10 = 0.346 mg/L (OECD TG 211, Daphnia magna); GLP, RL1; read-across: partially unsaturated TEA-Esterquat

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC10

Effect concentration:

0.346 mg/L

Additional information

No experimental data are available for the target substance oleic acid-based TEA-Esterquat. However, a Daphnia reproduction test is available for the structurally related source substance partially unsaturated TEA-Esterquat. A justification for read-across is attached to Iuclid section 13.

 

A Daphnia magna reproduction test (semi-static, 21 d) of partially unsaturated TEA-Esterquat was conducted at the test facility according to OECD 211 (2012). The test species was Daphnia magna STRAUS. Ten daphnids, held individually, were used per concentration level and control. At test start the daphnids were < 24 hours old. The study was carried out under semi-static conditions with a daily renewal. The aim of the test was to assess the effects on the reproduction capacity and other test item-related effects or parameters such as the intrinsic rate of the natural increase, first appearance of living juveniles, occurrence of aborted eggs and stillborn juveniles, adult mortality, body length and dry weight of the parental daphnids.

Nominal concentrations of the test item were selected based on the results of a preliminary range finding test (non-GLP) as follows: 2.00 - 6.32 - 20.0 - 63.2 - 200 mg dispersion/L (separation factor √10), corresponding to 0.208 – 0.658 – 2.08 – 6.58 – 20.8 mg test item/L (dry content of the suspension: 10.4%) and the time weighted mean measured concentrations 0.0935 - 0.268 - 0.984 - 2.41 - 9.29 mg test item/L.

A stock solution with a nominal concentration of 200 mg dispersion/L was prepared as specified in section 5.2 and was used for the preparation of the concentration levels in the range of 2.00 - 200 mg dispersion/L in a geometric series with a separation factor of √10 by dilution with dilution water.

The test item concentrations were analytically verified via LC-MS/MS in the fresh media at the start of the exposure-renewal intervals on days 0, 7, 14, 16 (0 hours) and in the old media at the end of the exposure intervals on days 1, 8, 15, 17 (24 hours, respectively) in all concentration levels and in the control.

The measured concentrations of the test item in fresh media at the start of the respective exposure-renewal intervals (0 hours) were in the range of 78 to 98% of the nominal concentrations. At the end of the respective exposure-renewal intervals (48 and 72 hours), the measured test item concentrations in the old media were in the range of <LOQ to 29% of the nominal concentrations.

Since the measured test item concentrations were not within ± 20% of the nominal concentrations, the time weighted mean measured test item concentrations were used for the evaluation of the effect-concentrations.

The environmental conditions were within the acceptable limits. The validity criteria of the test guideline were met. To be valid, the maximum control mortality rate of parent animals must not exceed 20% and the mean offspring number of the survived females at day 21 must be at least 60.0. In the present test, the mortality was 20% and the mean offspring number of the survived females was 95.6 in the control.

The Cochran-Armitage trend-test revealed a significant trend in mortality. Thus, according to OECD 211 it is required to report the effects for the cumulative offspring per introduced parent provided these values are lower than in the cumulative offspring per survivor.

 

Endpoints for Reproduction and Mortality (based on the time weighted mean measured test item concentrations and the nominal test item concentration)

Effect values	time weighted mean measured test item concentrations [mg/L]	nominal test item concentration [mg/L]
EC10 Reproduction (with 95% confidence limits)	0.346 (0.150 – 0.797)	0.728 (0.347 – 1.53)
EC20 Reproduction (with 95% confidence limits)	0.460 (0.208 – 1.042)	0.973 (0.475 – 2.02)
EC50 Reproduction (with 95% confidence limits)	0.792 (0.303 – 2.118)	1.69 (0.698 – 4.09)
LOEC Reproduction	0.984	2.08
NOEC Reproduction	0.268	0.658
LC10 Adult mortality after 21 days (with confidence limits)	Not applicable	Not applicable
LC20 Adult mortality after 21 days (with confidence limits)	Not applicable	Not applicable
LC50 Adult mortality after 21 days (with confidence limits)	1.02 (0.984 - 2.41)*	2.39 (2.08 - 6.58)*
LOEC Adult mortality after 21 days	2.41	6.58
NOEC Adult mortality after 21 days	0.984	2.08

 

* The goodness of fit for this parameter is low.