Reaction products of 2-[[2-(dimethylamino)ethyl]methylamino]ethanol di(hexanoate) and ethyl oxirane

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2015-10-20 to 2015-10-22

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study according to GLP principles

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Qualifier:

equivalent or similar to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

The limit concentration and the control were analytically verified via LC-MS/MS analysis at the start (0 hours) and at the end of the exposure (48 hours). The method was validated prior to this study according to SANCO 3029/99 rev.4 (2000). At the start of the exposure (0 hours), sampling was carried out after preparation of the limit concentration. At the end of the exposure (48 hours), samples were taken directly from the test vessels.

Vehicle:

no

Details on test solutions:

The limit concentration (100 mg/L of the test item were weighed out) was freshly prepared with dilution water (ISO test water as specified below) before the start of the exposure (0 hours). The stock solution was mixed thoroughly by manual agitation.

Test organisms (species):

Daphnia magna

Details on test organisms:

Daphnia magna STRAUS is the preferred species in accordance with the test guidelines and is bred at the test facility. The daphnids were kept in glass vessels (2 - 3 L capacity) with approximately 1.8 L culture medium at 20 +/- 2°C in an incubator. The incubator is illuminated 16 hours per day with a light intensity of max. 20 µE/m2* s1. Elendt M4, according to ELENDT (1990), modified to a total hardness of 160 to 180 mg CaCO3/L, was used. The culture daphnids were fed at least 5 times per week ad libitum with a mix of unicellular green algae, e.g. Pseudokirchneriella subcapitata and Desmodesmus subspicatus, with an algae cell density of > 106 cells/mL. The algae were cultured at the test facility.
20 daphnids, divided into 4 replicates, each with 5 daphnids, were used for the limit concentration and the control. At the start of the exposure 2 to 24 hours old daphnids from a healthy stock were used for the study. Juvenile daphnids were removed from the culture vessels latest 22 hours before the start of the exposure and discarded. The juveniles born within this period of max. 22 hours preceding the exposure were used for the test after additional 2 hours after collection. No first brood progeny was used for the test. Daphnids were left in dilution water for acclimatisation for at least 2 hours.
The daphnids were not fed during the study

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Test temperature:

nominal: 18 - 22°C, constant within ± 1°C
During the test period, the temperature in the incubator was 19 – 20 °C.

pH:

Nominal test item start of exposure end of exposure
concentration (o hours) (48 hours, 4 Replicates)

100 mg/L 7.25 7.74 7.74 7.73 7.74
Control 7.85 7.68 7.74 7.79 7.82

Dissolved oxygen:

Dissolved O2 concentration [mg/L]
Nominal test item start of exposure end of exposure
concentration (o hours) (48 hours, 4 Replicates)

100 mg/L 8.71 8.37 8.46 8.62 8.57
Control 8.84 8.43 8.51 8.43 8.52

Nominal and measured concentrations:

The test was conducted as a limit test with anominal concentration of 100 mg/L. The measured concentration of the test item at the start of the exposure (0 hours) was 96.1 mg/L. At the end of the exposure (48 hours), the measured concentration of the test item was 110 mg/L. The measured test item concentrations were within ± 20 % of the nominal concentration. This indicates that the test item concentration was successfully maintained for the duration of the test. The effect levels are therefore based on the nominal concentration of the test item.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

The effects of the limit concentration were deduced directly from the observed immobilisation rates. All effect levels (EC10 / 50 / 100) were based on the nominal concentration of the test item, because measured test item concentrations were within ± 20 % of the nominal concentration.

Results with reference substance (positive control):

The percentage immobility for the reference item was determined after 24 hours. The EC50-value with 95 % confidence limits (CI) was calculated by sigmoidal dose-response regression. The EC50-value for the most recent of the monthly performed reference tests was:
EC50: 1.61 mg/L (CI 1.43 - 1.82 mg/L)
The EC50-value of the reference item potassium dichromate after 24 hours is within the prescribed concentration range of 0.6 - 2.4 mg/L of quality criteria according to AQS P 9/2 (02/2000) for daphnids clone 5 cultured in Elendt M4 medium. The EC50-value of the reference item is also within the recommended range of 0.6 - 2.1 mg/L according to OECD-Guideline 202.

Immobilisation Rates after 24 and 48 hours of Exposure in the Definitive Test  (n = 20, divided into 4 replicates with 5 daphnids each)

Nominal test item concentration   [mg/L]	IMMOBILISATION [%]
	24 hours					48 hours
	Replicates					Replicates
	1	2	3	4	MV	1	2	3	4	MV
100	0	0	0	0	0	0	0	0	0	0
Control	0	0	0	0	0	0	0	0	0	0

Measured Concentrations and Percent of the Nominal Concentration of the Test Item during the Definitive Test

Sampling date	2015-10-20 Start of the exposure 0 hours		2015-10-22 End of the exposure 48 hours
Start of analysis	2015-10-20		2015-10-22
Nominal test item concentration [mg/L]
	Meas. conc. [mg/L]	%	Meas. conc. [mg/L]	%
100	96.1	96	110	110
Control	< LOQ		< LOQ

Meas. conc. = measured concentration of the test item, mean value of 2 injections, dilution factors taken into account

%             = percent of the nominal concentration of the test item

LOQ     = limit of quantification (1 mg/L of the test item)

Validity criteria fulfilled:

yes

Conclusions:

At the analytically confirmed nominal concentration of 100 mg/L of the test item, no effects were observed on Daphnia magna.

Executive summary:

In the acute immobilisation test with Daphnia magna (STRAUS),the effects of a limit concentration of 100 mg/L of the test item were determined according to OECD 202 (2004). The limit test was conducted under static conditions over a period of 48 hours.

The limit concentration of 100 mg/L of the test item was freshly prepared with dilution water before the start of the exposure (at 0 hours) and mixed thoroughly by manual agitation. The limit concentration was visually clear throughout the exposure period.

Twenty daphnids each were exposed to the limit concentration and the control.

The concentrations of the test item were analytically verified via LC-MS/MS at the start (0 hours) and at the end of the exposure (48 hours) in the limit concentration and the control. The measured concentration of the test item at the start of the exposure (0 hours) was 96.1 mg/L and 110 mg/L at the end of the exposure (48 hours). The measured test item concentrations were within ±20 % of the nominal concentration. This indicates that the test item concentration was successfully maintained for the duration of the test therefore the effect levels are based on the nominal concentration of the test item.

The water quality parameters (i.e. pH-value and dissolved oxygen concentration), measured at the start (0 hours) and at the end of the exposure (48 hours), were within the acceptable limits. The validity criteria of the test guidelines were fulfilled.

Description of key information

In the acute immobilisation test with Daphnia magna (STRAUS),the effects of a limit concentration of 100 mg/L of the test item were determined according to OECD 202 (2004). The limit test was conducted under static conditions over a period of 48 hours.
The limit concentration of 100 mg/L of the test item was freshly prepared with dilution water before the start of the exposure (at 0 hours) and mixed thoroughly by manual agitation. The limit concentration was visually clear throughout the exposure period.
Twenty daphnids each were exposed to the limit concentration and the control.
The concentrations of the test item were analytically verified via LC-MS/MS at the start (0 hours) and at the end of the exposure (48 hours) in the limit concentration and the control. The measured concentration of the test item at the start of the exposure (0 hours) was 96.1 mg/L and 110 mg/L at the end of the exposure (48 hours). The measured test item concentrations were within ±20 % of the nominal concentration. This indicates that the test item concentration was successfully maintained for the duration of the test therefore the effect levels are based on the nominal concentration of the test item.
The water quality parameters (i.e. pH-value and dissolved oxygen concentration), measured at the start (0 hours) and at the end of the exposure (48 hours), were within the acceptable limits. The validity criteria of the test guidelines were fulfilled.

At the analytically confirmed nominal concentration of 100 mg/L of the test item, no effects were observed on Daphnia magna.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC50

Effect concentration:

> 100 mg/L

Additional information

At the analytically confirmed nominal concentration of 100 mg/L of the test item, no effects were observed on Daphnia magna.