[No public or meaningful name is available]

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:

January 2021 to March 2021

Reliability:

1 (reliable without restriction)

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

yes

Remarks:

Neonates from parents which had been cultured in ISO media were used rather than Elendt M4 medium as stated in the study plan. This was considered to have no adverse effect on outcome of the study as both media are of similar quality.

GLP compliance:

yes

Specific details on test material used for the study:

Test material is a solid (deliquescent) and has a purity of approximately 94.5%. The test material has an expiry date of 3rd December 2021 and should be stored at room temperature in the dark under nitrogen.

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

A nominal amount of test item (50 mg) was dissolved in test media and the volume adjusted to 500 mL to give the 100 mg/L test concentration from which a series of dilutions was made to give further test concentrations f 10, 1.0 and 0.1 mg/L.

Test organisms (species):

Daphnia magna

Details on test organisms:

Adult daphnids were maintained in 150 mL glass vessels containing 100 mL Elendt M4 medium in a temperature controlled room maintaining temperatures at 18 to 22 oC. The lighting cycle was controlled to give 16 hours light and 8 hours darkness with 20 minute dawn and dusk transition periods. Each culture was fed daily with a mixture of algal suspension (Raphidocelis subcapitata) and GEMMA Micro 300 fish food suspension.

Culture conditions ensured that reproduction by parthenogenesis. Gravid adults were isolated the day before initiation of the test, such that young daphnids produced overnight were less than 24 hours old. These young were removed from the cultures and used for testing.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

Observations of the test animals were carried out at 24h and 48h for the definitive test.

Hardness:

2.5 mmol/L (= 250 mg/L as CaCo3)

Test temperature:

Between 18-22 oC with a maximum deviation of +/- 1 oC.

pH:

7.8-8.2

Dissolved oxygen:

> 3 mg/L

Nominal and measured concentrations:

Nominal test concentrations (mg/L) - 10, 18, 32, 56 and 100
0-Hour measured test concentrations (mg/L) - 10.6, 19.5, 34.5, 60.4, 112
48-Hour measured test concentrations (mg/L) - 4.98, 10.4, 21.1, 43.5, 90.4

Analysis of the test preparations at 0 hours showed the measured test concentrations to range from 106-112% of nominal. A decline in the measured test concentrations was observed at 48 hours in the range of 50-90% of nominal.

Given this decline in measured test concentrations it was considered justifiable to base the results of the geometric mean measured test concentrations in order to give a "worst case" analysis of the data:

Geometric mean measured test concentration (mg/L) - 7.3, 14, 27, 51, 101

Details on test conditions:

TEST SYSTEM

150 mL, closed, glass test vessels were used. Each test and control vessel contained 100 mL of test media and were covered to reduce evaporation. The flow through was static. At the start of the test five daphnids were placed in each test and control vessel containing the test preparations. Four replicate test and control vessels were prepared. The contents of the vessel were not aerated.


TEST MEDIUM / WATER PARAMETERS

The test medium was reconstituted water Elendt M4 medium with a water hardness of 2.5 mmol/L (= 250 mg/L as CaCO3) and an alkalinity of 0.9 mmol/L. The pH of the prepared media was in the range of 7.96 +/- 0.3 and was stored at approximately 21 oC. If necessary the pH was adjusted with NaOH of HCl.

OTHER TEST CONDITIONS

A photoperiod of 16 hours light (between 200 and 1200 LUX) and 8 hours darkness with a 20 minute dawn and dusk period.

EFFECT PARAMETERS MEASURED

Immobilisation was the parameter measured at 24 and 48 hours.


RANGE-FINDING STUDY

In the initial range finding test Daphina magna were exposed to a series of nominal test concentrations of 0.1, 1.0, 10 and 100 mg/L. Given that 20% immobilisation was observed in the 0.1, 1.0 and 10 mg/L test groups, it was considered appropriate to conduct a second range finding test at nominal concentrations of 0.1, 1.0, 10 and 100 mg/L. In the second range finding test no immobilisation was observed to have occured in the 0.1, 1.0 and 10 mg/L test cultures. Furthermore, no sub-lethal effects were observed throughout the test.

Based on the results from the second range finding test, test concentrations of 10, 18, 32, 56 and 100 mg/L were selected for the definitive test.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

101 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

51 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

89 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Results with reference substance (positive control):

The results from the positive control were within the normal range for this reference item. The results of inter laboratory tests and a technical corrigendum to ISO 6341 give a 24h EC50 of 0.6 mg/L to 2.1 mg/L.

Reported statistics and error estimates:

The EC50 values and associated confidence limits at 24 and 48 hours and the slope of the response curve and its standard error were calculated by Probit analysis using Linear Maximum-Likelihood regression. The LOEC and NOEC at 24 hours were calculated using Fisher's Exact Binomial Test with Bonferroni correction incorporating Qualitative Trend Analsysi by Contrasts. The NOC and LOEC at 48 hours were calculated using the Step-down Cochran-Armitage Test incorporating Tarone's Test and Qualitative Trend Analysis by Contrasts.

All results were calculated using the ToxRat computer software package.

Geometric Mean Measured Test Concentration (mg/L)	Number Immobile at 24 hours
	R1	R2	R3	R4	Total	%
							Control	0	0	0	0	0	0
7.3	0	0	0	0	0	0
14	0	0	0	0	0	0
27	0	0	0	0	0	0
51	0	0	0	0	0	0
101	2	1	1	1	5

 

Geometric Mean Measured Test Concentration (mg/L)	Number Immobile at 48 hours
	R1	R2	R3	R4	Total	%
Control	0	0	0	0	0	0
7.3	0	0	0	0	0	0
14	0	0	0	0	0	0
27	0	0	1	0	1	5
51	0	1	0	0	1	5
101	4	3	2	4	13	65

Validity criteria fulfilled:

yes

Conclusions:

The 48 hour EC50 was 89 mg/L and the 48 hour NOEC was 51 mg/L.

Executive summary:

The short-term toxicity of 1-propanaminium, N,N,N-trimethyl-3-[(1-oxo-3-phenyl-2-propenyl)amino]-, chloride to aquatic invertebrates was determined during a GLP compliant study performed according to OECD testing guideline 202 using the species Daphnia magna.

Analysis of the test preparations at 0 hours showed measured test concentrations to range from 106-112% of nominal.  A decline in measured test concentrations was observed at 48 hours in the range of 50-90% of nominal.  Given this decline in measured test concentrations it was considered justifiable to calculate the results based on the geometric mean measured test concentrations in order to give a "worst-case" analysis of the data,  The mean geometric measured concentrations were determined to be 7.3, 14, 27, 51 and 101 mg/L.

The 48 hour EC50 was 89 mg/L and the 48 hour NOEC was 51 mg/L.

Description of key information

The short-term toxicity of 1-propanaminium, N,N,N-trimethyl-3-[(1-oxo-3-phenyl-2-propenyl)amino]-, chloride to aquatic invertebrates was determined during a GLP compliant study performed according to OECD testing guideline 202 using the species Daphnia magna.

Analysis of the test preparations at 0 hours showed measured test concentrations to range from 106-112% of nominal.  A decline in measured test concentrations was observed at 48 hours in the range of 50-90% of nominal.  Given this decline in measured test concentrations it was considered justifiable to calculate the results based on the geometric mean measured test concentrations in order to give a "worst-case" analysis of the data,  The mean geometric measured concentrations were determined to be 7.3, 14, 27, 51 and 101 mg/L.

The 48 hour EC50 was 89 mg/L and the 48 hour NOEC was 51 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC50

Effect concentration:

89 mg/L