Amides, tall-oil fatty, N-[3-(dimethylamino)propyl]

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:

48 hours

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

no

Details on sampling:

No analytical method was available, therefore there was no sampling. The test item concentrations were lower than the quantification limit of the analysis method. Calculations of effective concentrations EC50 were thus performed using nominal values.

Vehicle:

no

Details on test solutions:

Osmotic water was used for the preparation of dilution water (resistivity > 1.8 MO).

For the preliminary test, item solutions at 1, 10, 50 and 100 mg/L were prepared as WAF. For the 1 and 10 mg/L concentrations, the solution was clear. For 50 and 100 mg/L concentrations, th solutions were filtered on Millipore HV 0.45 µm membranes, which were pre-saturated.
For the definitve test, a stock solution of the test item diluted in water was prepared at the beginning of the test (time 0) by mixing 10 mg of Emulsamine AT-O in 1 Litre of dilution water.

Test organisms (species):

Daphnia magna

Details on test organisms:

- organisms Daphnia magna Straus (Cladocera, Crustacea), clone 5 or clone A
- animals come from a stock breading in the laboratory reared in VOLVIC water added with vitamin B12, Na2SeO3, 5H2O, Ca(NO3)2, spiruline, unicellular green fresh-water algae Pseudokirchneriella subcapitata.
- selection of test organisms less than 24 hours old is made by filtration.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

N/A

Hardness:

no data

Test temperature:

Between 18.7ºC and 19.7ºC

pH:

T0 = 7.83 to 7.93;
T48h = 7.64 to 7.74

Dissolved oxygen:

T0 = 8.5 mg O2/l;
T48h = 7.5 to 8.1 mg O2/l

Salinity:

no data

Nominal and measured concentrations:

Test substance concentrations were lower than the quantification limit of the analysis method. Calculations of effective concentration EC 50 were thus performed using nominal values.
Nominal test concentrations were 0.016, 0.031, 0.063, 0.125, 0.25, 0.5, and 1 mg/L.

Details on test conditions:

The study was performed in a thermostated room. The temperature was continuously recorded in one flask. Physicochemical parameters were measeured using a Mettler Toledo 345 pH meter for measures of pH, and with a WTW OXI 538 oxymeter for dissolved oxygen measurement.

PRELIMINARY TEST:
The study was performed using 30 mL glass bottle stoppered with PTFE bungs and sealed with aluminium caps.

A certain volume of the test solution was added into the test flasks. 5 Daphnia aged from 24 hours were added into each test flask which were then totally filled with the test solution. 2 replicates were prepared for each concentration. 2 control flasks were prepared under the same conditions, with no test item. Test flasks were incubated in darkness at a temperature of 19 ± 0.5 °C.

After 48 hours of incubation, mobile Daphnia were counted.

Dissolved O2 and pH were measured at the highest tested concentration and in the control.

Results of the preliminary test served to define the concentration range used in the definitive test.

DEFINITIVE TEST
Volumetric flasks were filled with the required volumes of the test item stock solution and dilution water in order to obtain the test solutions at concentrations varying from 0.016 mg/L to 1 mg/L. The definitive test was performed to a concentrations range forming a geometric pregression with a factor of 2.

5 Daphnia aged from 24 hours were added into each flask which were then totally filled with the test solution. 4 replicates were prepared for each concentration. 4 control flasks were prepared under the same conditions, with no test item. Test flasks were incubated in darkness at a temperature of 19.2 ± 0.5 °C.

After 24 hours of incubation, mobile Daphnia were counted and flasks replaced under incubation. At time 48 hours mobile Daphnia were counted.

Dissolved O2 and pH were measured at the highest concentration and in the control at the beginning, and at all concentrations and in the control at the end of the test.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate, volumetric standard quality purity > 99.95 %.

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

0.58 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 0.38 - 1.1

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

0.28 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

no data

Results with reference substance (positive control):

The report contains a potassium dichromate EC50 of 0.79 mg/L. The expected range detaield in ISO 6341 is 0.5 to 1.7 mg/L. Therefore the report result is valid.

Reported statistics and error estimates:

Results were determined using the Probit/log model.

The appearance of the test solutions was visually checked at the beginning and at the end of the test. Solutions were found to be clear over the period of the test. No precipitation was observed at the end of the test.

Table 1: The percentage inhibition of Daphnia mobility

Nominal Concentration	Immobilisation (%)
mg/L	24-hour	48-hour
0	0	0
0.016	0	0
0.031	0	0
0.063	0	0
0.125	0	0
0.25	0	10
0.5	30	100
1	95	100

In the definitive test, the test item concentrations were lowere than the quantification limit of the analysis method. Calculations of effective concentration EC₅₀were thus performed using nominal values.

Validity criteria fulfilled:

yes

Remarks:

see details in conclusions

Conclusions:

The study was conducted to determine the toxicity of Amides, rape-oil, N-[3-(dimethylamino)propyl] to Daphnia magna. This study was carried out in accordance with OECD Guideline 202 and EC method C.2. 
The study was performed in compliance with its quality criteria:
- Immobilisation in the control did not exceed 10% at the end of the test;
- Test Daphnia in the control were not trapped at the surface of the water; concentration of dissolved oxygen in the test vessels remained above 2 mg/l at the end of the test and pH did not vary by more than 1 unit.

Executive summary:

The acute toxicity (inhibition of mobility) of the test substance to Daphnia magna was assessed according to the method C2 of the European Directive 92/69/EEC and in the guideline 202 (part I) of the OECD.

Daphnia were exposed to a range of concentrations of the test substance dissolved in dilution water. The toxic effect measured during the assay was the inhibition of mobility after time period of 24 hours and 48 hours.

The test was performed using closed flasks as testing vessels. Flasks were entirely filled with test solutions and closed with butyl rubber caps covered with PTFE. Daphnia were exposed in a static test to a concentration range of 0.016 to 1 mg/l, forming a geometric progression with a factor of 2. The test was performed with 5 Daphnia per vessels. Testing flasks were incubated in darkness at 19.2 ± 0.5 for 48 hours. For each exposure concentration, the percentage of immobilisation after 24 hours and 48 hours using Probit/log model. The results are presented in the following table:

Effective concentrations (mg/l)
	Value	95 % CI
EC50-24h	0.58	0.38-1.1
EC50-48h	0.28	ND

CI: confident interval; ND: not determined

As no analytical method was available, effective concentration shown in the previous table have been calculated using the initial nominal concentrations of the test substance.

The appearance of the test solutions was visually checked at the beginning and at the end of the test. Solutions were found to be clear over the period of the test. No precipitation was observed at the end of the test.

It was not possible to check item concentration as values were lower than the quantification limit of the method used.

The study was performed according to the OECD principles of Good Laboratory Practice (GLP).

Description of key information

It is assessed from the methods of manufacture the starting materials and the similarity of the end product compositions that EC272-047-7 is sufficiently similar in all respects to EC800-353-8 that it is a sensible approach to use a read-across approach. A comparison of the two substances and a read-across justification can be found in section 13 of this dataset

Additional information

An acute toxicity of Amides, C18-unsatd., N-[3-(dimethylamino)propyl] to Daphnia magna was assessed according to the method C2 of the European Directive 92/69/EEC and in the guideline 202 (part I) of the OECD (Gancet, 2002). However, this study was considered as diregarded since it was not possible to check item concentrations. A long-term aquatic toxicity study on daphnia (OECD 211) is available (Kean, 2010). Therefore, in accordance with Column 2 of Annex VII (required in section 9.1.1), the acute toxicity test can be waived.