1-(4-tert-butylphenyl)-3-(4-methoxyphenyl)propane-1,3-diol

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:

September 30, 2016 - January 9, 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

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:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

R,R-1-(4-tert-butyl-phenyl)-3-(4-methoxy-phenyl)-propane-1,3-diol

Molecular formula:

C20H26O3

IUPAC Name:

R,R-1-(4-tert-butyl-phenyl)-3-(4-methoxy-phenyl)-propane-1,3-diol

Constituent 2

Reference substance name:

R,S-1-(4-tert-Butyl-phenyl)-3-(4-methoxy-phenyl)-propane-1,3-diol

Molecular formula:

C20H26O3

IUPAC Name:

R,S-1-(4-tert-Butyl-phenyl)-3-(4-methoxy-phenyl)-propane-1,3-diol

Constituent 3

Reference substance name:

S,S-1-(4-tert-Butyl-phenyl)-3-(4-methoxy-phenyl)-propane-1,3-diol

Molecular formula:

C20H26O3

IUPAC Name:

S,S-1-(4-tert-Butyl-phenyl)-3-(4-methoxy-phenyl)-propane-1,3-diol

Constituent 4

Reference substance name:

S,R-1-(4-tert-Butyl-phenyl)-3-(4-methoxy-phenyl)-propane-1,3-diol

Molecular formula:

C20H26O3

IUPAC Name:

S,R-1-(4-tert-Butyl-phenyl)-3-(4-methoxy-phenyl)-propane-1,3-diol

Test material form:

solid

Details on test material:

Minimum purity 95% w/w

Specific details on test material used for the study:

Designation: Art. 132720
Synonym: Avodiol
Product name: RonaCare® Pristine Bright™
CAS-No.: 955359-35-0
Batch: EH16000620
Purity (HPLC): 95% (w/w)
Appearance: Light cream, free flowing granules
Water solubility: 45.7 mg/L (± 2.8 mg/L) (OECD 105)
Stability under
test conditions: Stable
Expiry date: June 30, 2018
Storage: +15°C to +25°C

Preparation of the Test Item:
A stock preparation with a test item concentration of 100 mg/L was freshly prepared. For that purpose, the test item was weighed in a calibrated flask and vehicle was added. The preparation was stirred with a magnetic stirrer for further 24 hours. Then the formulation was passed through a filter membrane (pore size: 0.2 µm). The filtrate was diluted with vehicle to the different test item concentrations.

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

Concentrations:
2.5, 5.5, 21.1, 26.6 and 58.6 mg/L

Sampling method:
Samples were taken and analyzed by HPLC from control and test media from both exposure periods, i.e. 0 - 24 hours and 24 - 48 hours. The maintenance of the test item concentration was checked by analysis of freshly prepared samples and after a period of 24 hours.

Sample storage conditions before analysis:
Samples were analyzed directly without storage.

Test solutions

Vehicle:

yes

Details on test solutions:

Macro nutrients (mg/L)
CaCI2 •2H20 293.80
MgSO4•7H20 123.30
NaHCO3 64.80
KCI 5.80
Na2SiO3•9H20 10.00
NaNO3 0.27
KH2PO4 0.14
K2HPO4 0.18

Trace elements (mg/L)
B 0.5000
Fe 0.2000
Mn 0.1000
Li, Rb and Sr 0.0500
Mo 0.0250
Br 0.0125
Cu and Zn 0.0063
Co and I 0.0025
Se 0.0010
V 0.0003

Macro nutrients (mg/L)
Na2EDTA • 2H20 2.50

Vitamins (µg/L):
Thiamine 75.00
B12 1.00
Biotin 0.75

- pH: 7.81 - 7.91
- Total hardness: 238 - 244 mg CaCO3/L
- O2-Concentration: 8.38 - 8.45 mg/L

Preparation of the Test Item:
A stock preparation with a test item concentration of 100 mg/L was freshly prepared. For that purpose, the test item was weighed in a calibrated flask and vehicle was added. The preparation was stirred with a magnetic stirrer for further 24 hours. Then the formulation was passed through a filter membrane (pore size: 0.2 µm). The filtrate was diluted with vehicle to the different test item concentrations.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

Species: Daphnia magna Straus
Origin: Daphnia magna Straus was originally obtained from IBACON GmbH (Roßdorf, Germany).
Culture conditions: The clone is bred in the laboratories of Merck KGaA (room 2068).
Parental daphnids are used for reproduction until they are about 6 weeks old. Thereafter, they are replaced by neonates.
Daphnids are kept individually in 100 mL glass vessels containing approximately 60 mL reconstituted water (ELENDT M4 medium) at a water temperature of 20 ± 2°C and a 16 hour light and 8 hour dark regime to ensure similar conditions as in the experiment. Offspring are removed from the vessels at least twice per week.
Feeding: The parental daphnids are fed ad libitum with unicellular green algae Desmodesmus subspicatus three times per week.
Age: Offspring less than 24 hours old were used for the study.
Acclimation period: same as test

Feeding during test: None

Study design

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Hardness:

238 - 244 mg CaCO3/L

Test temperature:

19.2 – 20.0°C

pH:

7.68 - 7.91

Dissolved oxygen:

8.06 - 8.38 mg/L

Nominal and measured concentrations:

Nominal concentrations: 2.5, 5.5, 12.1, 26.6 and 58.6 mg/L
Measured concentrations: 1.092, 2.436, 5.355, 11.387 and 26.277 mg/L (calculated geometric mean)

Details on test conditions:

EXPOSURE:
The study was performed in an air-conditioned room. For the study 20 mL glass test tubes containing at least 20 mL either reconstituted water (control group) or test medium (test item groups) were used. Each test vessel contained five daphnids resulting in 4 mL medium per daphnid. They were not fed and the media were not aerated during the exposure.

The test was performed as a semi-static test in open vessels.

The duration of exposure was 48 hours. During the exposure period, the mobility of the daphnids was assessed daily, i.e. after 24 and 48 hours.

NO. OF DAPHNIDS:
Control Group: 20 daphnids
2.5 mg/L: 20 daphnids
5.5 mg/L: 20 daphnids
12.1 mg/L: 20 daphnids
26.6 mg/L: 20 daphnids
58.6 mg/L: 20 daphnids

STABILITY OF THE TEST ITEM
In a pre-test (non-GLP) the stability of the test item in reconstituted water for daphnids and algae was investigated. In this test it was shown, that the test item concentration in reconstituted water for daphnids was stable over a period of 48 hours (approx. 45 - 50% recovery from the nominal concentration at all time points). However, a significant decrease at the highest concentration (100 mg/L) was observed in reconstituted water for algae starting after 24 hours (Broschard, 2016) in both open and closed vessels. As a precautionary measure, this study in daphnids was performed as a semi-static test in open vessels.

CONCENTRATION(S)
The present study was performed as a semi-static test with five different concentrations of 2.5, 5.5, 12.1, 26.6 and 58.6 mg/L in an open system.

For the control, reconstituted water (ELENDT M4 medium) was used.

VEHICLE
Reconstituted water (ELENDT M4 medium) was used as vehicle.

Macro nutrients (mg/L)
CaCI2 •2H20 293.80
MgSO4•7H20 123.30
NaHCO3 64.80
KCI 5.80
Na2SiO3•9H20 10.00
NaNO3 0.27
KH2PO4 0.14
K2HPO4 0.18

Trace elements (mg/L)
B 0.5000
Fe 0.2000
Mn 0.1000
Li, Rb and Sr 0.0500
Mo 0.0250
Br 0.0125
Cu and Zn 0.0063
Co and I 0.0025
Se 0.0010
V 0.0003

Macro nutrients (mg/L)
Na2EDTA • 2H20 2.50

Vitamins (µg/L):
Thiamine 75.00
B12 1.00
Biotin 0.75

- pH: 7.81 - 7.91
- Total hardness: 238 - 244 mg CaCO3/L
- O2-Concentration: 8.38 - 8.45 mg/L
- Culture medium different from test medium: no
- Intervals of water quality measurement: 24h (semi-static)


OTHER TEST CONDITIONS
- Photoperiod: 16h light / 8h dark
- Light intensity: The mean light intensities were 716 Lux and 723 Lux prior to and at the end of the exposure period, respectively.

References:

ELENDT, B.-P. Selenium deficiency in Crustacea. An ultrastructural approach to antennal damage in Daphnia magna Straus.
Protoplasma 154, 25-33, 1990

Reference substance (positive control):

no

Remarks:

No positive control used in this study. The accuracy and reliability of the test method is demonstrated periodically as recommended by guidelines with potassium dichromate.

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

10 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: The EC50 values were calculated with the geometric mean concentrations.

Effect concentrations 2

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

5.8 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: The EC50 values were calculated with the geometric mean concentrations.

Details on results:

The test item Art. 132720 (Avodiol) showed a 48h EC50 of 5.8 mg/L.

Results with reference substance (positive control):

Potassium dichromate:
24h EC50 1.00 mg/L (0.85 – 1.23 mg/L)
48h EC50 0.66 mg/L (n.d.)

The test item Art. 104864 (Potassium dichromate) showed a 24h EC50 value of 1.0 mg/L which is within the range of the published data of 0.6 to 1.7 mg/L (Council Regulation (EC) No. 440/2008) and 0.6 to 2.1 mg/L (OECD Guideline No. 202).

Any other information on results incl. tables

Objective

The objective of this study was to determine the effect of the test item Art. 132720 (Avodiol) on the immobilization of Daphnia magna.

Study Design

Juvenile daphnids were exposed to different concentrations of the test item (nominal concentrations: 0, 2.5, 5.5, 12.1, 26.6 and 58.6 mg/L) in an open semi-static system. 20 daphnids, divided into four replicates, each with five animals were used per concentration and control. Concentrations of the test item Art. 132720 (Avodiol) in the test media were analyzed via HPLC with UV detection directly after preparation and after 24 hours. The daphnids were observed for immobilization after 24 and 48 hours of exposure.

Results

The measured concentrations of the test item were within the range of 40.1% to 47.2% of the nominal concentrations as given in the following table:

	Analytical results
	0h Fresh preparation		24h Old preparation		24h Fresh preparation		48h Old preparation
Nominal	[mg/L]	%	[mg/L]	%	[mg/L]	%	[mg/L]	%
0 mg/L	<LOD	-	<LOD	-	<LOD	-	<LOD	-
2.5 mg/L	1.117	44.7	1.002	40.1	1.168	46.7	1.089	43.6
5.5 mg/L	2.463	44.8	2.283	41.5	2.565	46.6	2.440	44.4
12.1 mg/L	5.390	44.5	5.082	42.0	5.596	46.2	5.366	44.3
26.6 mg/L	11.679	43.9	11.112	41.8	11.665	43.9	11.105	41.7
58.6 mg/L	26.080	44.5	24.933	42.5	27.682	47.2	26.485	45.2

The EC₅₀values were calculated with the geometric mean concentrations (1.092, 2.436, 5.355, 11.387 and 26.277 mg/L).

After exposure of daphnids to nominal concentrations of 2.5, 5.5, 12.1, 26.6 and 58.6 mg/L for 48 hours, the following results were obtained:

	Number of daphnids immobilized / exposed		% of daphnids immobilized
Nominal	24 hours	48 hours	24 hours	48 hours
0.0 mg/L	0/20	0/20	0%	0%
2.5 mg/L	0/20	0/20	0%	0%
5.5 mg/L	0/20	0/20	0%	0%
12.1 mg/L	2/20	10/20	10%	50%
26.6 mg/L	11/20	18/20	55%	90%
58.6 mg/L	20/20	20/20	100%	100%

No effect on the mobility of the daphnia was observed at the two lowest nominal concentrations of 2.5 mg/L and 5.5 mg/L. A concentration dependent immobilization was observed at nominal concentrations between 12.1 and 58.6 mg/L.

For the test item, Art. 132720 (Avodiol), the following EC50 values for daphnids were determined:

24h EC50       10.0 mg/L (8.1 – 12.4 mg/L)

48h EC50       5.8 mg/L (4.7 – 7.1 mg/L)

Conclusion

Under the conditions of the present study, the test item Art. 132720 (Avodiol) showed a 48h EC₅₀of 5.8 mg/L.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Under the conditions of the present study, the test item Art. 132720 (Avodiol) showed a 48h EC50 of 5.8 mg/L.

Executive summary:

This study was performed according to GLP and the methods applied are fully compliant with OECD TG 202. Art. 132720 (Avodiol), dissolved in reconstituted water, was tested in an open semi-static system. Under the conditions of the present study, the test item Art. 132720 (Avodiol) showed a 48h EC₅₀ of 5.8 mg/L.