Guerbet alcohols, C24-26, branched and cyclic

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

June - September 2020

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

Version / remarks:

October 2, 2012

Deviations:

yes

Remarks:

water temperature exceeded the required 18-22 °C during the test for about three days (temperature: 22-23.2 °C)

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

During the test, TOC concentrations of the test item were analyzed once a week in fresh and old media (i. e. analyses were made on a sample from the same solution - when freshly prepared and at renewal), in the control and the test solutions.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: 1.00 g test item were weighed and added into a glass bottle filled with 10 l test water. The solution was mixed by magnetic stirring at a speed of 200-250 rpm for about 24 hours and allowed to stand for 30-60 minzes. After standing, the solution was drawn from the tap at about 7 cm higher than the bottom of the bottle and then used for exposure and dilution of the test solutions of 1 and 10 mg/L.
- Eluate:
- Differential loading:
- Controls:
- Chemical name of vehicle (organic solvent, emulsifier or dispersant):
- Concentration of vehicle in test medium (stock solution and final test solution(s) or suspension(s) including control(s)):
- Evidence of undissolved material (e.g. precipitate, surface film, etc.):
- Other relevant information:

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia
- Strain/clone: Daphnia magna Straus
- Age at study initiation (mean and range, SD): less than 24 hours
- Source: Applying Chemistry Department Pesticide Environmental Evaluation Laboratory of China Agricultural University.
- Feeding during test : yes
- Food type: algal suspension of Chlorella sp. and Desdemodesmus suspicatus;
- Amount/frequency: 0.10 mg/C/Daphnia/d during days 0-8; 0.15 mg C/Daphnia/d the following days

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

21 d

Hardness:

190-200 mg/l (as CaCO3)

Test temperature:

19.2-23.2 °C

pH:

7.95-8.44

Dissolved oxygen:

min. 3 mg/l

Nominal and measured concentrations:

Nominal concentrations: 100 mg/l

Verfication of test concentrations:
The arithmetic mean measured TOC concentration (deduced control) in the samples of the test solution was determined to be 0.0678 mg/l over the whole test period. Based on the analysed Total Organic Carbon Content of 81.0 % of the test item the mean arithmetic mean TOC concentration corresponds to 0.0837 mg/l.

Details on test conditions:

TEST SYSTEM
- Test vessel: 250 ml glass beaker
- Type (delete if not applicable): losely covered to reduce the loss of water due to evaporation and to avoid the entry of dust into the solution
- Material, size, headspace, fill volume: 90 ml
- Aeration: at least 24 hours before the test to attain oxygen saturation
- Type of flow-through (e.g. peristaltic or proportional diluter):
- Renewal rate of test solution (frequency/flow rate): daily
- No. of organisms per vessel: 1
- No. of vessels per concentration (replicates): 10
- No. of vessels per control (replicates): 1
- No. of vessels per vehicle control (replicates): 10


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: tap water after being treated with Aquapro Pure Water System
- Total organic carbon: < 2 mg/l

OTHER TEST CONDITIONS
- Photoperiod: 16 hr light, 8 h darkness
- Light intensity: 1000 - 1500 lux for cool white light

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : daily count of living offspring, presence of aborted eggs, dead offspring, mortality of parent animals (daily), body length of living parent animals (once at end of test)
, time of production of first brood, total broods of each parent

TEST CONCENTRATIONS

- Justification for using less concentrations than requested by guideline: Limit test based on the results of the Preliminary study (dose range finding study) and the information on the low solubility of the test item.

Range finding study:
- Test concentrations: 1, 10, 100 mg/l
- Results used to determine the conditions for the definitive study: Thenumber of juveniles from the parent animals was not significantl inhibited in comparison to the control.

Reference substance (positive control):

no

Key result

Duration:

21 d

Dose descriptor:

NOELR

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Key result

Duration:

21 d

Dose descriptor:

NOELR

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality: Number of living offspring produced per surviving parental animal {for Daphnia magna, TG 211}

Details on results:

During the test, no immobilization or mortality was observed in control group and test group. There was no significant difference for total living offspring per parent between the control and test group. During the test, there were no dead offspring or aborted eggs.
In the control and the test group the first brood began on day 7 to 8. No significant difference was found for the first brood between the control and test group. There was also no significant difference in the number of total broods per parent and no differences were found for body length between control and test group.

Loading rate (mg/l)	mean living offspring +/- standard deviation (p-value)	Inhibition (%)	Time to Production of first Brood	Mean Total broods of each parent	Mean Parental  Mortality	Mean Body length of Parental Animals at the End of test (mm) +/- standard deviation
0 (control)	301 +/-25	-	7.9 +/-0.3	6.8 +/-0.4	0 %	3.58 +/- 0.04
100	277 +/-31 (0.57)	8	7.9 +/- 0.3	6.7 +/-0.5	0 %	3.59 +/- 0.03

Validity criteria fulfilled:

yes

Conclusions:

Total number of living offspring of each parental animal, time to production of first brood, total broods of each parent and the body length of living parent animals were analyzed by a two-sided Student's t-test using a 5% significance level to obtain the lowest observed effect loading rate (LOEL) and no observed effect loading rate (NOEL). The 21d NOEL/LOEL for all parameters (total living offspring for each parental animal, time to production of first brood, total broodds of each parent, body length of living parental animal) are: NOEL >= 100 mg/l; LOEL >100 mg/l.

Executive summary:

A reproduction test with Guerbet alcohosl, C24 -26, branched and cyclic was conducted with Daphnia magna over a 21d exposure period under semi-static conditions.

According to the information on the water solubility of the test item and the results of the range-finding test, the definite test was carried out as a limit test with 100 mg/l as loading rate. The test was conducted on 10 animals each

for test and control group. During the test no immobilization or mortality was observed in the control and test group. No effecsts on the total number of living offspring, time to production of first brood, total broods of each parent and the body length of living paranetal animals at the end of the study were observed. Therefore the No Observed Effect Loading rates for all these parameters are >= 100 mg/l.

Description of key information

A reproduction test with Guerbet alcohosl, C24 -26, branched and cyclic was conducted with Daphnia magna over a 21d exposure period under semi-static conditions. The test was performed as limit with a loading rate of 100 mg/l. The test was conducted on 10 animals each for test and control group. During the test no immobilization or mortality was observed in the control and test group. No effects on the total number of living offspring, time to production of first brood, total broods of each parent and the body length of living paranetal animals at the end of the study were observed. Therefore the No Observed Effect Loading rates for all these parameters are >= 100 mg/l.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L