2-Propanone, reaction products with diphenylamine

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:

19 February 2018 to 21 February 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

OECD Guidelines for Testing of Chemicals, No.:202 (Adopted: 13 April 2004) OECD: Paris.

Deviations:

yes

Remarks:

See "Any other information" for details

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

Commission Regulation (EC) No 761/2009 of 23 July 2009 amending, for the purpose of its adaptation to technical progress, Regulation (EC) No 440/2008 laying down test methods pursuant to Regulation (EC) No 1907/2006 of the European Parliament and of the Council on the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACh), Annex IV Part C, C.2 (published in the Official Journal of the European Union L 220 of 24 August 2009).

Deviations:

yes

Remarks:

See "Any other information" for details

Qualifier:

according to guideline

Guideline:

EPA OPPTS 850.1010 (Aquatic Invertebrate Acute Toxicity Test, Freshwater Daphnids)

Version / remarks:

EPA Health Effects Test Guidelines, OCSPP 850.1010.

Deviations:

yes

Remarks:

See "Any other information" for details

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

No further details specified in the study report.

Analytical monitoring:

yes

Details on sampling:

Based on the agreement with the sponsor and due to the fact that the Test Item is an UVCB the analytical measurement was performed by TOC analysis. Only the sum of the carbon content of the Test Item could be measured this way (and this did not change by the end of the test, independently from the stability), measurement was sufficient only at the beginning and end of the renewal periods to justify that the Test Item is present in the test solution, since more accurate data cannot be provided by TOC. However, the solubility of the Test Item was so low that all results were All samples were analysed directly after sampling. The analytical method and results are provided in the Analytical Report.

Vehicle:

no

Details on test solutions:

Because the Test Item is a UVCB (Chemical Substances of Unknown or Variable Composition, Complex Reaction Products and Biological Materials), a test solution was be prepared using a saturated solution method according to the Guidance Document on Aquatic Toxicity Testing of Difficult Substances and Mixtures, OECD No. 23. A saturated Test Item solution at 100 mg/L Test Item nominal loading rate (WAF) was prepared individually by dispersing/dissolving the needed amount of Test Item into the test medium (ISO medium) two days before the start of each renewal period. This solution was shaken for about 24 hours at approximately 30°C and then was equilibrated for about 24 hours at approximately 20°C. The non-dissolved test materials were removed by filtration through a fine (0.22 µm) filter to give the 100% saturated solutions. As only limit test was carried out, further dilution of this saturated solution was not performed.

Test organisms (species):

Daphnia magna

Details on test organisms:

Species and strain: Daphnia magna
Source: Szent István University, Department of Aquaculture 2100 Gödöllő, Páter Károly u. 1. – Hungary
Justification of strain: Daphnia magna is the standard species of the acute immobilisation test.
Number of animals: There were 20 animals in test and control groups respectively, divided into 4 replicates (5 animals / replicate)
Age of the animals: They were less than 24 h old at the beginning of the test
Acclimatization: There was no acclimatization because the water used was similar to the culture water

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Post exposure observation period:

No post exposure observation period specified in the study report.

Hardness:

The reconstituted water (ISO medium) had a total hardness of 249 mg/L (as CaCO3).

Test temperature:

The water temperature was measured at the start of the test and 24-hour intervals thereafter in each test vessel. The test temperature was in the range of 20.2 – 20.8°C measured in the test vessels.
The additionally measured temperature in the climate chamber was between 19.8 and 20.9°C.

pH:

The pH of the test solution was not adjusted and not varied by more than 1.5 units in any one test. The pH was measured at the start and at the end of each renewal period in each test vessel and was in the range of 7.03 – 7.24.

Dissolved oxygen:

The dissolved oxygen concentration was measured in each test vessel at the start and at the end of each renewal period and was in the range of 7.1– 8.6 mg/L.

Salinity:

Not specified

Conductivity:

Not specified

Nominal and measured concentrations:

No significant toxicity was observed in the preliminary study therefore 100 mg/L Test Item nominal loading rate (WAF) and one Control was used in the Main test.

Details on test conditions:

PERFORMANCE OF THE TEST
The test duration was 48 hours. Twenty animals, divided into four groups (glass beaker) of five animals each (at least 5 mL test solution/animal) were used at the test concentration and for the control in a semi-static system. The animals were not fed during the test.
The choice of the test concentration was done on the basis of the results of a preliminary range-finding test.

Preliminary Range-Finding Test
A concentration range-finding test was conducted to determine the approximate toxicity of the Test Item so that appropriate test concentrations could be selected for use in the definitive test. Ten daphnids (divided into two replicates) in each test concentration and control were exposed for 48 hours under semi-static conditions.

OBSERVATIONS
The immobility or mortality of the Daphnia was determined by visual observation 24 and 48 hours after the start of the test. Those animals not able to swim within 15 seconds after gentle agitation of the test beaker are considered to be immobile. The number of immobilised animals and the percentage of immobility were determined at 24 and 48 hours.
The water temperature, the oxygen concentrations and pH of the controls and the test solution were measured at the beginning and at the end of the renewal periods.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Key result

Duration:

48 h

Dose descriptor:

EL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

other: test item loading rate

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

NOELR

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

LOELR

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

VALIDITY
There was no immobilized animal in the control group and the dissolved oxygen concentration at the end of the test in control and test vessels was more than 3 mg/L. All validity criteria were within acceptable limits and therefore the study can be considered as valid.

Results with reference substance (positive control):

For the evaluation of the quality of the Daphnia clone and the experimental conditions, Potassium dichromate is tested at least twice a year to demonstrate satisfactory test conditions.
The date of the last study (Study Code: 17/367-023DA) with reference item Potassium dichromate (batch no.: A0345704) is: 06-07 December 2017. The 24h EC50: 0.65 mg/L, (95 % confidence limits: 0.61 – 0.70 mg/L).

Reported statistics and error estimates:

No statistical analysis was performed because of the lack of toxic effects.
The EL50, NOELR, LOELR and EL100 values were determined directly from the raw data.

Results of the Preliminary Range-Finding Test

Nominal concentration [mg/L nominal loading rates WAFs]	Untreated control	0.1	1	10	100
Number of treated / immobilised animals	10 / 0	10 / 0	10 / 0	10 / 0	10 / 1

 

Number of percentage of immobilised animals

Test Group	Number of treated animals	Number of immobilised animals
		24 hours		48 hours
		Number	Percent	Number	Percent
Control	20	0	0	0	0
100 mg/L nominal loading rate WAF	20	0	0	0	0

 

Temperature measured in the test vessels (°C)

Test group	Replicate	Measuring
		0 h (fresh media)	24 h (old media)	24 h (fresh media)	48 h (old media)
Control	1	20.6	20.3	20.8	20.2
	2	20.6	20.3	20.8	20.2
	3	20.6	20.3	20.8	20.2
	4	20.6	20.3	20.8	20.2
100 mg/L nominal loading rate WAF	1	20.6	20.3	20.8	20.2
	2	20.6	20.3	20.8	20.2
	3	20.6	20.3	20.8	20.2
	4	20.6	20.3	20.8	20.2

 

Oxygen concentration measured in the test vessels (mg/L)

Test group	Replicate	Measuring
		0 h (fresh media)	24 h (old media)	24 h (fresh media)	48 h (old media)
Control	1	7.7	8.5	7.6	8.5
	2	7.7	8.5	7.6	8.6
	3	7.7	8.6	7.6	8.5
	4	7.7	8.5	7.6	8.5
100 mg/L nominal loading rate WAF	1	7.2	8.5	7.1	8.5
	2	7.2	8.5	7.1	8.5
	3	7.2	8.5	7.1	8.5
	4	7.2	8.5	7.1	8.4

 

pH measured in the test vessels

Test group	Replicate	Measuring
		0 h (fresh media)	24 h (old media)	24 h (fresh media)	48 h (old media)
Control	1	7.10	7.12	7.08	7.03
	2	7.10	7.12	7.08	7.03
	3	7.10	7.15	7.08	7.04
	4	7.10	7.17	7.08	7.05
100 mg/L nominal loading rate WAF	1	7.18	7.19	7.24	7.05
	2	7.18	7.19	7.24	7.05
	3	7.18	7.20	7.24	7.07
	4	7.18	7.21	7.24	7.09

 

Validity criteria fulfilled:

yes

Conclusions:

Under the conditions of the Daphnia magna acute immobilisation study the calculated and observed endpoints for the effect of Test Item were the followings:

The 24h, 48h, EL50 value: > 100 mg/L nominal loading rate WAF
The 48h EL100 value: > 100 mg/L nominal loading rate WAF
The 48h NOELR : 100 mg/L nominal loading rate WAF
The 48h LOELR : > 100 mg/L nominal loading rate WAF

Based on the results of the study, the Test Item had no toxic effect at saturation on Daphnia; the EL50 results and the LOELR are higher than the solubility level of the Test Item in the test medium.

Executive summary:

Acute toxicity of Test Item was assessed with Acute Immobilisation Test on Daphnia magna, over an exposure period of 48 hours in a semi-static system.

 

Because no toxic effect was observed at the solubility level of the Test Item in the preliminary test, only this test concentration 100 mg/L Test Item nominal loading rate (WAF) at the solubility level of the Test Item in the test medium and one control group were tested in a limit test in the definitive study.

 

Based on the agreement with the Sponsor and due to the fact that the Test Item is an UVCB the analytical measurement was performed by TOC analysis. Only the sum of the carbon content of the Test Item could be measured this way, however the solubility of the Test Item was so low that all results were <LOQ (5 mg carbon/L).

 

Twenty animals, divided into 4 groups (glass beaker) of 5 animals each were used at the test and for the control group. All validity criteria were met during this study.

 

Under the conditions of the Daphnia magna acute immobilisation study the calculated and observed endpoints for the effect of Test Item were the followings:

 

The 24h, 48h, EL50 value: > 100 mg/L nominal loading rate WAF

The 48h EL100 value: > 100 mg/L nominal loading rate WAF

The 48h NOELR: 100 mg/L nominal loading rate WAF

The 48h LOELR: > 100 mg/L nominal loading rate WAF

 

Based on the results of the study, the Test Item had no toxic effect at saturation on Daphnia; the EL50 results and the LOELR are higher than the solubility level of the Test Item in the test medium.

Description of key information

The 24h, 48h, EL50 value: > 100 mg/L nominal loading rate WAF

The 48h EL100 value: > 100 mg/L nominal loading rate WAF

The 48h NOELR: 100 mg/L nominal loading rate WAF

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L

Additional information

Acute toxicity of Test Item was assessed with Acute Immobilisation Test on Daphnia magna, over an exposure period of 48 hours in a semi-static system.

Because no toxic effect was observed at the solubility level of the Test Item in the preliminary test, only this test concentration 100 mg/L Test Item nominal loading rate (WAF) at the solubility level of the Test Item in the test medium and one control group were tested in a limit test in the definitive study.

Twenty animals, divided into 4 groups (glass beaker) of 5 animals each were used at the test and for the control group.

 

Under the conditions of the Daphnia magna acute immobilisation study the calculated and observed endpoints for the effect of Test Item were the followings:

The 24h, 48h, EL50 value: > 100 mg/L nominal loading rate WAF

The 48h EL100 value: > 100 mg/L nominal loading rate WAF

The 48h NOELR: 100 mg/L nominal loading rate WAF

The 48h LOELR: > 100 mg/L nominal loading rate WAF

 

Based on the results of the study, the Test Item had no toxic effect at saturation on Daphnia; the EL50 results and the LOELR are higher than the solubility level of the Test Item in the test medium.