4-bromo-3,3,4,4-tetrafluorobut-1-ene

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

April 14 2021 to April 17 2021

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2021

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

4-bromo-3,3,4,4-tetrafluorobut-1-ene

EC Number:

242-440-8

EC Name:

4-bromo-3,3,4,4-tetrafluorobut-1-ene

Cas Number:

18599-22-9

Molecular formula:

C4H3BrF4

IUPAC Name:

4-bromo-3,3,4,4-tetrafluorobut-1-ene

Test material form:

liquid

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

Test water samples were collected from the batches of test solution prepared for each treatment and control group at the beginning of the test, and pooled samples from each test chamber in each treatment and control group at prior to renewal at approximately 24 hours, after renewal at approximately 24 hours and at 48 hours (± 1 hour) to measure concentrations of the test substance. Test solution samples (2.0 mL) were collected from mid-depth and placed in 40 mL glass septum capped vials and 2 mL auto-sampler vials with minimized headspace. Negative control samples (10 mL) were collected in the same manner. Both sets of samples collected at each sampling interval were processed immediately for analysis.

Test solutions

Vehicle:

no

Details on test solutions:

A primary stock solution was prepared by mixing a calculated amount (0.4001 g) of test substance into UV sterilized well water at a nominal concentration of 100 mg a.s./L. The stock solution concentration was adjusted to 100% active ingredient during preparation, based on the reported test substance purity (99.967%). A 4000 mL glass volumetric flask was brought close to full volume using UV sterilized well water. The test substance was weighed into a tared 3mL plastic syringe fitted with an 18 gauge stainless steel needle and then was dosed underneath the surface of the dilution water in the 4000 mL glass volumetric flask. The flask was brought to full volume using UV sterilized well water and was inverted at least 20 times to mix. After mixing, the stock solution appeared clear and colorless. The resulting 100 mg a.i./L primary stock was used to make the remaining four test solutions.

Aliquots of the 100 mg a.i./L primary stock solution were measured out into 2000 mL glass volumetric flasks. The flasks were brought to full volume using UV sterilized well water and a Teflon-lined stir bar was added. The flasks were stirred on a magnetic stir plate for 10 minutes. The resulting test solutions were divided into four 8oz French Squares and filled to minimum headspace, then capped with a Teflon-lined lid.

After distribution to the test chambers, the negative control solution and all test solutions appeared clear and colorless. The negative control solution was dilution water only.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

Daphnids used in the test were <24-hour old neonates obtained from cultures maintained by Eurofins-Easton. Identification of the species was verified by the supplier of the original stock culture (Aquatic BioSystems Inc.).

Adult daphnids were cultured in water from the same source and at approximately the same temperature as used during the test. During the 2 week period immediately preceding the test, water temperatures in the cultures ranged from 19.6 to 21.4ºC, the pH of the water ranged from 7.8 to 8.4, and the dissolved oxygen concentrations were 7.1 mg/L (78% of saturation). The 4 adult daphnids used to supply neonates for the test were held for 13 days prior to collection of the juveniles for testing, and had each produced at least one previous broods. Adult daphnids in the culture had produced an average of at least three young per adult per day over the 7 day period prior to the test. The adults showed no signs of disease or stress, no ephippia were produced during the holding period, and mortality in the culture stock was <10% in the two-day period prior to test initiation.

Loading in each test chamber during the test was approximately 40 mL of test solution per daphnid.

Study design

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Hardness:

180 mg/L as CaCO3

Test temperature:

Refer to table 3 in field 'any other information on materials and methods incl. tables'

pH:

Refer to table 3 in field 'any other information on materials and methods incl. tables'

Dissolved oxygen:

Refer to table 3 in field 'any other information on materials and methods incl. tables'

Conductivity:

Specific conductance at test initiation, 389 µS/cm

Nominal and measured concentrations:

See Table 4 under Results and Discussion, additional data.

Details on test conditions:

TEST SYSTEM
Test chambers were 8 ounce glass French squares filled to capacity (236 mL) and covered with plastic Teflon-lined lids resulting in minimal head space. The depth of the test water in a representative chamber of the negative control was 12.4 cm. All test chambers were labeled with the study number, test concentration and replicate designation. The test chambers were impartially positioned by treatment group in a temperature controlled environmental chamber to maintain the target water temperature throughout the test period.
No aeration. Renewal of test solution after 24 hours.

No. of organisms per vessel: 5
No. of vessels per concentration (replicates): 4
No. of vessels per control (replicates): 4


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: The water used for organism holding and testing was freshwater obtained from a well approximately 40 meters deep located on the Eurofins-Easton site. The well water was passed through a sand filter and pumped into a 37,800 L storage tank where the water was aerated with spray nozzles. Prior to use in the test system, the water was filtered to 0.45 µm to remove fine particles and was passed through an ultraviolet (UV) sterilizer.
- Total organic carbon: mean < 2 mg C/L for 4-week period immediately preceding the test.
- Metals: refer to attached document ' metals and pesticide analysis' in attached background material. Results are for periodic analyses.
- Pesticides: refer to attached document ' metals and pesticide analysis' in attached background material. Results are for periodic analyses.
- Chlorine: not measured
- Alkalinity: 194 mg/L as CaCO3
- Ca/mg ratio: 2.57 (Results are for periodic analyses)
- Conductivity: 337 – 385 µS/cm
- Culture medium different from test medium: no
- Intervals of water quality measurement: Temperature/dissolved oxygen and pH were measured at start, at 24 hours (before and after renewal) and after 48 hours (study end)

OTHER TEST CONDITIONS
- Adjustment of pH: none
- Photoperiod: 16 hours light/8 hours darkness
- Light intensity: 709 Lux at the surface of the water at start of test, for one representative chamber

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Cumulative number of immobile daphnids, general observation. Observation intervals: approx. 4.5 hours, 24 hours and 48 hours

RANGE-FINDING STUDY
- Test concentrations: nominal concentrations of 0.24, 0.81, 2.7, 9.0 and 30 mg a.i./L
- 0% immobility at top dose

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

66.2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 2

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

50 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 3

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

5.1 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

act. ingr. (total fraction)

Basis for effect:

mobility

Effect concentrations 4

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

2 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

act. ingr. (total fraction)

Basis for effect:

mobility

Details on results:

Because the test substance is volatile, rigorous precautions were taken to minimize losses through evaporation during the tests and collection and analysis of samples to avoid losses through volatilization. Despite the special handling and precautions, the measured concentrations resulted in concentrations well below the nominal concentrations, therefore nominal concentrations are more representative of exposure to the test system. Measured concentrations of the samples ranged from approximately 3.2 to 13% of nominal concentrations 6.3, 13, 25, 50, 100 mg a.i./L. When measured concentrations of the samples were averaged, the mean measured test concentrations for this study were 0.28, 0.42, 0.83, 2.0 and 13 mg a.i./L, representing 4.4, 3.2, 3.3, 3.9 and 13% of nominal concentrations, respectively. Although the results of the study were based on geometric mean measured test concentrations, key results are reported as nominal.
Percent immobility in the 6.3, 13, 25, 50, 100 mg a.i./L nominal (0.28, 0.42, 0.83, 2.0 and 13 mg a.i./L, measured) treatment groups at test termination was 0, 0, 0, 0 and 100%, respectively. Therefore in this study, the highest test concentration causing no immobility at test end was 50 mg a.i./L (2.0 mg a.i./L, measured), the lowest test concentration causing 100% immobility at test end was 100 mg a.i./L (13 mg a.i./L, measured), and the NOEC was 50 mg a.i./L (2.0 mg a.i./L, measured). EC50 values at 24 and 48 hours were determined from the immobility data. Please refer to attached background material for concentration-response curve.
Please refer to table 5 in field 'any other information on results, incl. tables' for main results on cumulative immobility and observations.

Reported statistics and error estimates:

The immobility data were analyzed using the computer program CETIS™ v1.9.3.0 (5). The
program was designed to calculate the EC50 value and the 95% confidence intervals. Based on the
immobility pattern in this study, the binomial method was used to calculate the 24 and 48-hour
EC50 values and 95% confidence intervals. Due to the method used to calculate the 48-hour EC50 value, the slope of the concentration-response curve could not be calculated. The no-observed-effect
concentration (NOEC) based on immobility was analyzed using Fisher Exact/Bonferroni-Holm Test in
CETIS™ v1.9.3.0. The highest test concentration causing no immobility at test end and the lowest test concentration causing 100% immobility at test end were determined by visual interpretation of the immobility data

Any other information on results incl. tables

Table 4

Measured Concentrations of 4-BROMO-3,3,4,4-TETRAFLUOROBUT-1-ENE (BTFB, CAS 18599-22-9) in Test Solution Samples 

Nominal Test Concentration (mg a.i./L)		Sample Number (783A-111-)	Sampling Time (Day)	Measured Concentration (mg a.i./L)^1,2	Percent of Nominal^2	Geometric Mean Measured Concentration (mg a.i./L)^2	Geometric Mean Measured Percent of Nominal^2
Negative		1	0	< LOQ	--	--	--
Control		7	1 (old)	< LOQ	--
		12	1 (new)	< LOQ	--
		17	2	< LOQ
6.3		2	0	0.112^3	1.77	0.28	4.4
		8	1 (old)	0.505	8.01
		13	1 (new)	0.273	4.33
		18	2	0.376	5.97
13		3	0	0.512^3	3.94	0.42	3.2
		9	1 (old)	0.363	2.79
		14	1 (new)	0.349	2.69
		19	2	0.458	3.52
25		4	0	0.855^3	3.42	0.83	3.3
		10	1 (old)	0.791	3.16
		15	1 (new)	0.594^3	2.37
		20	2	1.17^3	4.68
50		5	0	1.74^3	3.48	2.0	3.9
		11	1 (old)	3.15	6.31
		16	1 (new)	1.30^3	2.60
		21	2	2.06^3	4.12
100		6	0	12.5	12.5	13^4	13^4
	^1   The limit of quantitation (LOQ) of 4-bromo-3,3,4,4-tetrafluorobut-1-ene (BTFB) in freshwater is set at 0.0100 mg a.i./L, defined as the lowest nominal concentration of matrix fortification samples with a mean recovery within 70-110% ^2   Results were generated using Excel 2010 in full precision mode.  Manual calculations may differ slightly. ^3Value extrapolated outside the curve.  Result is reported here. ^4Geometric mean not calculted due to single point measured

 

Table 5

Cumulative Immobility and Observations

 

Geometric Mean Measured Concentration (mg a.i./L)	Rep.	No. Exposed	~4.5 Hours		24 Hours		48 Hours		Cumulative Percent Immobile
			Number Immobile^1	Observations^2	Number Immobile^1	Observations^2	Number Immobile^1	Observations^2
Negative	A	5	0	5 AN	0	5 AN	0	5 AN	0
Control	B	5	0	5 AN	0	5 AN	0	5 AN
	C	5	0	5 AN	0	5 AN	0	5 AN
	D	5	0	5 AN	0	5 AN	0	5 AN
0.28	A	5	0	5 AN	0	5 AN	0	5 AN	0
	B	5	0	5 AN	0	5 AN	0	5 AN
	C	5	0	5 AN	0	5 AN	0	5 AN
	D	5	0	5 AN	0	5 AN	0	5 AN
0.42	A	5	0	5 AN;	0	5 AN	0	5 AN	0
	B	5	0	5 AN	0	5 AN	0	5 AN
	C	5	0	5 AN	0	5 AN	0	5 AN
	D	5	0	5 AN	0	5 AN	0	5 AN
0.83	A	5	0	5 AN;	0	5 AN	0	5 AN	0
	B	5	0	5 AN	0	5 AN	0	5 AN
	C	5	0	5 AN	0	5 AN	0	5 AN
	D	5	0	5 AN	0	5 AN	0	5 AN
2.0	A	5	0	5 AN;	0	5 AN	0	5 AN	0
	B	5	0	5 AN	0	5 AN	0	5 AN
	C	5	0	5 AN	0	5 AN	0	5 AN
	D	5	0	5 AN	0	5 AN	0	5 AN
13	A	5	5	--	5	--	5	--	100
	B	5	5	--	5	--	5	--
	C	5	5	--	5	--	5	--
	D	5	5	--	5	--	5	--
^1  Cumulative number of immobile daphnids.  Any immobile daphnids were removed from the test chambers at each observation interval.  ^2  Observations of surviving organisms:  AN = appear normal.

 

 

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

Immobility in the control group was 0%. There were no signs of disease or stress observed in the control group. Dissolved oxygen concentration remained ≥8.0 mg/L.

Conclusions:

The cladoceran, Daphnia magna, was exposed for 48 hours under static-renewal conditions to five nominal concentrations of 4-BROMO-3,3,4,4-TETRAFLUOROBUT-1-ENE (BTFB, CAS 18599-22-9) ranging from 6.3 to 100 mg a.i./L. All conditions for test validity were achieved. The measured concentrations of 4-BROMO-3,3,4,4-TETRAFLUOROBUT-1-ENE (BTFB, CAS 18599-22-9) in the 6.3, 13, 25, 50, and 100 mg a.i./L treatment groups was 4.4, 3.2, 3.3, 3.9 and 13% of nominal concentrations, respectively. Based on geometric mean measured test concentrations, the 48 hour EC50 value was 5.1 mg a.i./L. The highest test concentration causing no immobility at test end was 2.0 mg a.i./L, the lowest test concentration causing 100% immobility at test end was13 mg a.i./L, and the NOEC was 2.0 mg a.i./L.

Based on nominal test concentrations, the 48 hour EC50 value was 66.2 mg a.i./L. The highest test concentration causing no immobility at test end was 50 mg a.i./L, the lowest test concentration causing 100% immobility at test end was100 mg a.i./L, and the NOEC was 50 mg a.i./L.