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Ecotoxicological information

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:
31 March - 4 June 2018
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2018
Report Date:
2018

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
Deviations:
no
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Test material form:
liquid
Details on test material:
Appearance: Straw to yellow syrup
Purity/Composition: Not indicated
Test item storage: At room temperature

Additional information
Test Facility test item number: 209099/A
Purity/Composition correction factor: No correction factor required
Test item handling: No specific handling conditions required
Specific details on test material used for the study:
Lot P7728
Dom: Nov 17 2016

Sampling and analysis

Analytical monitoring:
yes
Details on sampling:
Samples for possible analysis were taken from all test concentrations and the control according to the schedule below. In addition, the glass wool containing the undissolved residue was kept for possible analysis.
Frequency at t=0 h and t=48 h
Volume 2.0 mL from the approximate centre of the test vessels
Storage Samples were stored in a freezer (≤-15°C) until analysis at the analytical laboratory of the Test Facility.
At the end of the exposure period, the replicates were pooled at each concentration before sampling.
Additionally, reserve samples of 2.0 mL were taken for possible analysis. If not used, these samples were stored in a freezer (≤-15°C) for a maximum of three months after delivery of the draft report, pending on the decision of the sponsor for additional analysis.

Test solutions

Vehicle:
no
Details on test solutions:
The batch of WICKENOL 535 tested was a straw to yellow syrup. The test item was a UVCB which was not completely soluble in test medium at the loading rates initially prepared. No correction was made for the purity/composition of the test item.
Preparation of test solutions started with loading rates individually prepared ranging between 1.0 and 100 mg/L. A 2-day period of magnetic stirring was applied to ensure maximum dissolution of the test item in medium. The obtained mixtures were allowed to settle for a period of 1 day. Thereafter, the aqueous Water Accommodated Fractions (WAFs) were collected by means of siphoning through glass wool and used as test concentrations. All test solutions were clear and colorless at the end of the preparation procedure with the exception of the highest concentration tested, which was slightly hazy.
Any residual volumes were discarded.

Test organisms

Test organisms (species):
Daphnia magna
Details on test organisms:
Species Daphnia magna (Crustacea, Cladocera) (Straus, 1820), at least third generation, obtained by a cyclical parthenogenesis under specified breeding conditions.
Source In-house laboratory culture with a known history.
Reason for selection This system has been selected as an internationally accepted invertebrate species.
Validity of batch Daphnids originated from a healthy stock, 2nd to 5th brood, showing no signs of stress such as mortality >20%, presence of males, ephippia or discoloured animals and there was no delay in the production of the first brood.
Characteristics For the test selection of young daphnids with an age of < 24 hours, from parental daphnids of more than two weeks old.
Breeding
Start of each batch With newborn daphnids, i.e. less than 3 days old, by placing about 250 of them into 5 litres of medium in an all-glass culture vessel.
Maximum age of the cultures 4 weeks
Renewal of the cultures After 7 days of cultivation half of the medium twice a week.
Temperature of medium 18-22°C
Feeding Daily, a suspension of fresh water algae.
Medium M7, as prescribed by Dr. Elendt-Schneider
(Elendt, B.-P., 1990: Selenium deficiency in Crustacea. An ultrastructural approach to antennal damage in Daphnia magna Straus. Protoplasma 154, 25-33).
Composition of medium M7:
Adjusted ISO medium: the following chemicals (analytical grade) are dissolved in tap water purified by Reverse Osmosis (RO-water, GEON Waterbehandeling, Berkel-Enschot, The Netherlands):
Macro salts: CaCl2.2H2O 211.5 mg/L
MgSO4.7H2O 88.8 mg/L
NaHCO3 46.7 mg/L
KCl 4.2 mg/L
Medium M7: trace elements, macronutrients and vitamins are added to freshly prepared ISO medium to reach the following concentrations:
Trace elements:
B 0.125 mg/L
Fe 0.05 mg/L
Mn 0.025 mg/L
Li, Rb and Sr 0.0125 mg/L
Mo 0.0063 mg/L
Br 0.0025 mg/L
Cu 0.0016 mg/L
Zn 0.0063 mg/L
Co and I 0.0025 mg/L
Se 0.0010 mg/L
V 0.0003 mg/L
Na2EDTA.2H2O 2.5 mg/L
Macro nutrients: Na2SiO3.9H2O 10.0 mg/L
NaNO3 0.27 mg/L
KH2PO4 0.14 mg/L
K2HPO4 0.18 mg/L
Vitamins: Thiamine 75.0 µg/L
B12 1.0 µg/L
Biotin 0.75 µg/L
The hardness: 180 mg/L expressed as CaCO3 and the pH: 7.7 ± 0.3.

Study design

Test type:
static
Water media type:
freshwater
Limit test:
yes
Total exposure duration:
48 h
Post exposure observation period:
Not applicable

Test conditions

Test temperature:
19-20 degrees C
pH:
8.0
Dissolved oxygen:
8.2 - 8.9 mg/l
Salinity:
NA
Nominal and measured concentrations:
. The measured concentration was 3.1 mg/L at the start of the test. This concentration decreased to 0.19 mg/L at the end of the exposure. Based on these results, effects parameters were based on the average exposure concentration of 0.78 mg/L.
Details on test conditions:
Test duration 48 hours
Test type Static
Test vessels 60 mL, all-glass
Medium Adjusted ISO medium
Number of daphnids 20 per concentration
Loading 5 per vessel containing 50 mL of test solution
Light 16 hours photoperiod daily
Reference substance (positive control):
yes

Results and discussion

Effect concentrationsopen allclose all
Duration:
24 h
Dose descriptor:
EC50
Effect conc.:
> 0.78 mg/L
Nominal / measured:
nominal
Conc. based on:
other: WAF
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
> 0.78 mg/L
Nominal / measured:
nominal
Conc. based on:
other: WAF
Details on results:
No biologically relevant immobility or other effects were observed in the control and at any of the concentrations tested. It should be noted that 10% effect is allowed in the control. Hence, immobility ≤10% was considered biologically irrelevant.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
In conclusion, the 48h-EC50 for Daphnia magna exposed to WICKENOL 535 exceeded an average exposure concentration of 0.78 mg/L.
Executive summary:

The objective of the study was to evaluate WICKENOL 535 for its ability to generate acute toxic effects on the mobility of Daphnia magna during an exposure period of 48 hours and, if possible, to determine the EC50at 24 and 48 hours of exposure.

The study procedures described in this report were based on the OECD guideline No. 202, 2004.In addition, procedures were based on the test methods described in the OECD series on testing and assessment number 23, 2000.

The batch of WICKENOL 535 tested was astraw to yellow syrup. The test item was a UVCB which wasnot completely soluble in test medium at the loading rates initially prepared.

A combined limit/range-finding test was performed. Water Accommodated Fractions (WAFs) were individually prepared at loading rates of 1.0, 10 and 100 mg/L and used as test concentrations.

No biologically relevant immobility or other effects were observed in the control and at any of the concentrations tested.

Samples taken from the limit concentration were analysed. The measured concentration was 3.1 mg/L at the start of the test. This concentration decreased to 0.19 mg/L at the end of the exposure. Based on these results, effects parameters were based on the average exposure concentration of 0.78 mg/L. 

The study met the acceptability criteria prescribed by the study plan and was considered valid.

In conclusion, the 48h-EC50forDaphnia magnaexposed to WICKENOL 535 exceeded an average exposure concentration of 0.78 mg/L, being considered the maximum soluble concentration of the test item in test medium.