4,4'-[2,2,2-trifluoro-1-(trifluoromethyl)ethylidene]diphthalic anhydride

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:

October to November 2021

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Deviations were noted during the test but these were not thought to have a significant effect on the results:

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

yes

Remarks:

See 'any other information on materials and methods'

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Batch number: CT20201015
Re-test date: 10th September 2022
Storage conditions: store in a cool dry place

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

A 1000 mg/L stock was prepared in deionised water, and the resulting mixture was stirred for one hour left to settle for one hour and its behaviour assessed.

As the material was observed to be poorly soluble, then it was stirred again for approximately 19 hrs and then left to settle for one hour and its behaviour assessed. As the material was observed to be poorly soluble the material was prepared by Water Accommodated Fractions (WAFs). Test material stocks were individually prepared by weighing out an appropriate amount of test material, adding ISO Test Water and stirring for approximately 20h. The stocks were then left to settle for 1h and the mid column of the stock was siphoned off, taking care to avoid siphoning any undissolved material.

Test organisms (species):

Daphnia magna

Details on test organisms:

The test organisms were sourced from ephippia supplied by Eco Cheshire Solutions, from MicroBioTests. The ephippia were incubated no more than 96h prior to test commencement, therefore the neonates were less than 24h old at test commencement. The D. magna were incubated in ISO reconstituted water. The animals were fed Pseudokirchneriella subcapitata during incubation and not fed during the test.

Test type:

static

Water media type:

other: ISO reconstituted water

Limit test:

no

Total exposure duration:

48 h

Hardness:

Not specified

Test temperature:

20 °C +/- 2 °C

pH:

6-9

Dissolved oxygen:

>3 mg/L

Salinity:

Not specified

Conductivity:

Not specified

Nominal and measured concentrations:

Nominal Concentrations: 100, 180, 320, 560, 1000, 1800, 3200, 5600 and 10,000 mg/L

Details on test conditions:

Tests were conducted in 100 ml capacity borosilicate glass crystallising dishes, each containing 50 mL of test medium covered with soda glass watch covers. Stock solutions found to have a pH outside the tolerable range 6.0 – 9.0 were adjusted to 8.0 +/- 0.2 with either 1M HCl or NaOH as is appropriate.

A range-finding test was conducted at concentrations of 1000, 100, 10 and 1 mg/L, plus four control vessels. Approximately ten animals were exposed per concentration. A definitive test was conducted using concentrations dependent on the magnitude of response evident in the range-finding test. The concentrations were arranged in a geometric series of at least five concentrations with a factor not exceeding 2.2, plus four control vessels. Approximately ten animals were exposed per replicate (20 per treatment).

The dilution water used in the test was ISO Reconstituted Test Water without additives.

The photoperiod was 16 h light and 8 h dark.

Reference substance (positive control):

yes

Remarks:

A reference test was conducted concurrently using potassium dichromate (K2Cr2O7) at concentrations of 0.32, 0.56, 1.0, 1.8 and 3.2 mg/L prepared from a main stock of 100 mg/L. The 100mg/L stock was stirred for a minimum of one hour, or until dissolved

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

29.9 mg/L

95% CI:

> 14.3 - <= 222

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

10 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

Control mortality was 2.5%

Results with reference substance (positive control):

- Results with reference substance valid - yes
- Relevant effect levels: yes
- Limit test: no
- Dose-response test: yes
24 h EC50 was 1.36 mg/L

Nominal Concentration (mg/L)	Number immobile at 24 h		Number immobile at 48 h		Total exposed
	Replicate a	Replicate b	Replicate a	Replicate b
100	0	0	0	0	20
180	0	0	4	4	20
320	1	0	7	5	20
560	0	0	5	4	20
1000	2	1	7	7	20
1800	1	1	4	5	20
3200	2	2	7	6	20
5600	4	5	9	8	20
10000	5	6	10	10	20

Validity criteria fulfilled:

yes

Conclusions:

In the definitive test 4,4’-[2,2,2-trifluoro-1-(trifluoromethyl)ethylidene]diphthalic anhydride (6FDA) exhibited a 48h EC50 value of 29.9 mg/L (Water Accommodated Fraction) to the freshwater crustacean D. magna in the aqueous phase.

Executive summary:

The short-term toxicity of 6FDA to aquatic invertebrates was determined during a GLP-compliant study performed according to OECD Guideline 202.

Since the substance was poorly water soluble, Water Accomodated Fractions (WAF) were prepared.  Results are expressed on the initial loading of the test substance required to produce effects.

The species was Daphnia magna.

A range finding test was performed to determine the concentrations to be used in the definitive test.  As a result, concentrations of 100, 180, 320, 560, 1000, 1800, 3200, 5600 and 10,000 mg/L were used during the definitive test.

The 48-hour EC50 was 29.9 mg/L and the 48-hour NOEC was 10 mg/L.

Description of key information

The short-term toxicity of 6FDA to aquatic invertebrates was determined during a GLP-compliant study performed according to OECD Guideline 202.

Since the substance was poorly water soluble, Water Accomodated Fractions (WAF) were prepared.  Results are expressed on the initial loading of the test substance required to produce effects.

The species was Daphnia magna.

A range finding test was performed to determine the concentrations to be used in the definitive test.  As a result, concentrations of 100, 180, 320, 560, 1000, 1800, 3200, 5600 and 10,000 mg/L were used during the definitive test.

The 48-hour EC50 was 29.9 mg/L and the 48-hour NOEC was 10 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC50

Effect concentration:

29.9 mg/L