trans-2-(4-Bromo-3-fluorophenyl)-5-butyl-[1,3]dioxane

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:

Jue 3 - July 25, 2019

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)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

At the start of the exposure and at the renewal (0 and 24 h), samples of the freshly prepared test item concentrations were taken and analyzed.
At renewal and at the end of the exposure (24 and 48 h), sampled of the 24 h old media were taken directly fron the test vessels and analyzed.

Vehicle:

yes

Remarks:

dilution water

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna STRAUS (Clone 5)
- Source: Institut für Wasser-, Boden und Lufthygiene (WaBoLu), Berlin, Germany
- Age: < 24 h

FEEDING DURING TEST
- Food type: 5 x per week ad libitum with a mix of unicellular green algae

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

265 (0 h) and 238 (24 h) mg CaCO3/L

Test temperature:

21.3 - 21.4 °C

pH:

7.65 - 8.06

Dissolved oxygen:

8.86 - 9.03 mg/L

Conductivity:

561-565 µS/cm

Nominal and measured concentrations:

6.25 - 12.5 - 25.0 - 50.0 - 100% saturated solution, which corresponds to the geometric mean measured test item concentrations:
0.0200 - 0.0414 - 0.0781 - 0.157 - 0.315 mg/L

Details on test conditions:

Test vessels:
Glass beakers, 50 mL capacity, loosely covered with watch glasses
Test volume: 20 mL
Number of daphnids and replicates: 20 daphnids, divided into 4 replicates, each with 5 daphnids were used for each concentration level and control.
Application: 20 g test solution per replicate was weighed out into each test vessel. This corresponds to 20 mL per test vessel. The daphnids were inserted with a samll amount of dilution water (start of the exposure) or test solution (water renewal) by pipette.
Renewal of the test solutions: The test solutions were renewed after 24 h. For this purpose, a second set of test vessels was filled with the freshly prepared test solutions and the daphnids were transferred by pipette.

Reference substance (positive control):

no

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 0.315 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: eqal to 100 mg/L (nominal)

Details on results:

No effects were observed on Daphnia magna in any of the tested concentration levels of the test item.

Results with reference substance (positive control):

EC50 (24 h) = 1.78 mg/L
valid range: 0.6 - 2.4 mg/L, acc. to AQS P 9/2 (02/2000)

1) Immobilization Rates after 24 and 48 hours of Exposure in the Definitive Test

Geometric mean measured test item concentration [µg/L]	IMMOBILIZATION [%]
	24 hours					48 hours
	Replicates					Replicates
	1	2	3	4	MV	1	2	3	4	MV
827	0	0	0	0	0	0	0	0	0	0
354	0	0	0	0	0	0	0	0	0	0
210	0	0	0	0	0	0	0	0	0	0
94.0	0	0	0	0	0	0	0	0	0	0
47.2	0	0	0	0	0	0	0	0	0	0
Control	0	0	0	0	0	0	0	0	0	0

2) Measured Concentrations during the Definitive Test

Sampling date	Fresh media, 0 hours	Old media, 24 hours		Fresh media, 24 hours	Old media, 48 hours		Geometric mean* measured concentration of the test item   [mg/L]
Nominal loading rate of the saturated solution of the test item [%]	Test Item
	Meas. conc. [mg/L]	Meas. conc. [mg/L]	%	Meas. conc. [mg/L]	Meas. conc. [mg/L]	%
100	0.227	0.168	74	0.571	0.449	79	0.315
50.0	0.110	0.0881	80	0.277	0.223	80	0.157
25.0	0.0532	0.0461	87	0.142	0.107	75	0.0781
12.5	0.0279	0.0252	90	0.0728	0.0570	78	0.0414
6.25	< LOQ*	< LOQ*		0.0377	0.0270	72	0.0200
Control	< LOQ	< LOQ		< LOQ	< LOQ		< LOQ

Meas. conc. = measured concentration of the test item, enrichment and dilution factors taken into account

%                = percentage of the initially measured concentration of the test item

LOQ           = limit of quantification of the analytical method (25 µg test item/L)

*                 = For the calculation of the geometric mean measured test item concentrations, ½ LOQ was taken into
   account for measured values below the LOQ

Validity criteria fulfilled:

yes

Conclusions:

Based on the geometric mean measured concentrations of the test item, the 48 hour-EC50 for Daphnia magna was > 0.315 mg/L (eq. nominal 100 mg/L).

Executive summary:

The information for this endpoint study record was obtained from an experimental study. The OECD GLP criteria were met and the methods applied are fully compliant with OECD TG 202. Based on the geometric mean measured concentrations of the test item, the 48 hour-EC50 for Daphnia magna was > 0.315 mg/L (eq. nominal 100 mg/L). Therefore, no adverse effects were observed up to the limit of water solubility.

Description of key information

Based on the geometric mean measured concentrations of the test item, the 48 hour-EC50 for Daphnia magna was > 0.315 mg/L (eq. nominal 100 mg/L).

Therefore, no adverse effects were observed up to the limit of water solubility.