Octadecene, reaction products with hexadecene, hydrogenated

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:

11 December 2019 to 13 December 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)

Version / remarks:

OECD Guideline for Testing of Chemicals, Section 2, No. 202, “Daphnia sp., Acute Immobilisation Test”, updated 13 April 2004.

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

EPA Guideline 712-C-96-114: OCSPP 850.1010, “Aquatic Invertebrate Acute Toxicity Test, Freshwater Daphnids” April 1996.

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

Commission Regulation (EU) 2017/735 of 14 February 2017 amending, for the purpose of its adaptation to technical progress, the Annex to Regulation (EC) No 440/2008 laying down test methods pursuant to Regulation (EC) No 1907/2006 of the European Parliament and of the Council on the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH), Annex IV Part C, C.2.

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

No further details specified in the study report.

Analytical monitoring:

yes

Details on sampling:

Duplicate samples were taken (2 x ~15 mL from three replicates) in glass tubes at the beginning and at the end of the experiment from the control and at the applied test concentration level.

Vehicle:

no

Details on test solutions:

The test solutions were prepared using a saturated solution method according to the Guidance Document on Aquatic Toxicity Testing of Difficult Substances and Mixtures, OECD No. 23 (2000).
Saturated test item solution with the nominal loading rate of 100.0 mg/L (water accommodated fractions, WAF) was prepared with direct addition of the test item, mixed into the algal growth medium (ISO Medium) and then continuously stirred gently for approximately 48 hours using magnetic stirrer. Then, the emulsion was settled for approximately 1 hour, and the middle layer was collected as the test solution. This test solution (100.0 mg/L WAF) was divided into two parts. The non-dissolved test material was removed by filtration through a fine (0.22 µm) filter to give the appropriate WAF solution in the first case, while the other set was not filtered and used as test solution as it is.
Prior to treatment of each renewal period, test item solutions were prepared by the method described above just before introduction of the Daphnia (start of the treatments).

Test organisms (species):

Daphnia magna

Details on test organisms:

Species and strain: Daphnia magna
Source: István Szent University, 2100 Gödöllő, Páter Károly u. 1, Hungary
Breeding: The Daphnia are bred in Ecotoxicological Laboratory of Charles River Laboratories Hungary Kft.
The health of the stock animals is continuously monitored by visual daily checking. Abnormal behaviour or significant decrease of population is recorded.
Justification of strain:Daphnia magna is the standard species of the acute immobilisation test.
Number of animals: There were 20 animals in test group and control group respectively, divided into 4 replicates (5 animals / replicate)
Age of the animals:They were less than 24 h old at the beginning of the test
Acclimatization:There was no acclimatization because the water used was similar to the culture water

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Post exposure observation period:

No post exposure observation period specified in the study report.

Hardness:

The reconstituted water (ISO medium) had a total hardness of 248 mg/L (as CaCO3).

Test temperature:

The water temperature was measured at the start and at the end of the renewal periods in one control test vessel. The test temperature was in the range of 20.5 – 20.9°C measured in the test vessels.
The additionally measured temperature in the climate chamber was between 20.4 – 21.1°C

pH:

The pH of the test solution was not adjusted and not varied by more than 1.5 units in any one test. The pH was measured at the start and at the end of the renewal periods in one test vessel both in the control and test item group and was in the range of 7.11 – 7.70.

Dissolved oxygen:

The dissolved oxygen concentration was measured in the control and in the test concentration in one replicate at the start and at the end of the renewal periods and was in the range of 7.0 – 8.9 mg/L.

Salinity:

No specified

Conductivity:

Not specified

Nominal and measured concentrations:

nominal loading rate (WAF)

Details on test conditions:

PERFORMANCE OF THE TEST
The test duration was 48 hours. Twenty animals, divided into four groups (glass beaker with a volume of 50 mL) of five animals each (~40 mL test solution/flask; 8 mL test solution/animal) were used at the test concentration and for the control in a semi-static system. The animals were not fed during the test.
Based on the analytical method validation (Study Code: 19/045-920AN), the test was performed under semi-static conditions. The frequency of the water renewal periods was 24 hours.
The choice of the test concentration was done on the basis of the results of a preliminary range-finding test.

Preliminary Range-Finding Test
A concentration range-finding test was conducted to determine the approximate toxicity of the test item so that appropriate test concentrations could be selected for use in the definitive test. Ten daphnids (divided into two replicates) in each test concentration and control were exposed for 48 hours under semi-static conditions (in absence of stability data).
Saturated test item solutions with the nominal loading rates of 0.1, 1.0, 10.0 and 100.0 mg/L (water accommodated fractions, WAFs) were individually prepared with direct addition of the test item, mixed into the test medium (aquarium water) and then continuously stirred gently for approximately 48 hours using magnetic stirrer. Then, the emulsions were settled for approximately 1 hour, and the middle layer was collected as the test solution in each tested level.
Test solution at the highest test level (100.0 mg/L WAF) was divided into two parts as described above.

Test item concentrations in the Definitive Test
Because a toxic response was not observed at the highest concentration level during the preliminary concentration range-finding test, a Limit Test was carried out using only one test concentration at 100 mg/L nominal loading rate (WAF) (a filtered and a non-filtered one in parallel to demonstrate that any effect observed is due to physical effects and not toxicity) and one control group in a semi-static system.

OBSERVATIONS
The immobility or mortality of the Daphnia was determined by visual observation 24 and 48 hours after the start of the test. Those animals not able to swim within 15 seconds after gentle agitation of the test beaker are considered to be immobile.
The number of immobilised animals and the percentage of immobility were determined at 24 and 48 hours.
The water temperature, the oxygen concentrations and pH of the control and the test solution were measured at the beginning and at the end of the renewal periods.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate (batch no.: A0345704) is: 05 - 06 September 2019.

Key result

Duration:

48 h

Dose descriptor:

NOELR

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

LOELR

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EL100

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

VALIDITY
There were no immobilized animals in the control group and the dissolved oxygen concentration at the end of the test in the control and test vessels was more than 3 mg/L.
All validity criteria were within acceptable limits and therefore the study can be considered as valid.

IMMOBILISATION
The number of immobilised animals and the percentage of immobility were determined at the 24th and 48th hour.
In addition to immobility, no abnormal behaviour or appearance of test animals was detected.
All of the animals got stuck at the surface of the unfiltered test solution, but separated and swam after gentle agitation of the test beaker; they were not considered to be immobile (with the exception of two animals as see above). However, it was considered that effect was due to physical effects and not toxicity.

Results with reference substance (positive control):

For the evaluation of the quality of the Daphnia clone and the experimental conditions, Potassium dichromate is tested at least twice a year to demonstrate satisfactory test conditions.
The date of the last study (Study Code: 19/238-023DA) with reference item Potassium dichromate (batch no.: A0345704) is: 05 - 06 September 2019.
The 24h EC50: 0.82 mg/L, (95 % confidence limits: 0.66 – 0.93 mg/L)

Reported statistics and error estimates:

No statistical analysis was performed because of the lack of toxic effects.
The EL50, NOELR, LOELR and EL100 values were determined directly from the raw data.

Results of the Preliminary Range-Finding Test

Nominal concentrations [mg/L nominal loading rate WAF]	Untreated control	0.1	1.0	10.0	100.0	100.0*
Number of treated / immobilised animals	10 / 0	10 / 0	10 / 4	10 / 6	10 / 10	10 / 0

*Remark: filtered solution

 

Animals got stuck at the surface of the unfiltered test solutions of 1.0, 10.0 and 100.0 mg/L nominal loading rate WAFs.

 

Number and percentage of immobilised animals

Test group	Number of treated animals	Number of immobilised animals
		24 hours		48 hours
		Number	Percent	Number	Percent
Control	20	0	0	0	0
100.0 mg/L nominal loading rate (unfiltered)	20	0	0	2	10
100.0 mg/L nominal loading rate (filtered)	20	0	0	0	0

 

DATA OF TEST CONDITIONS

Test conditions during the Test

Parameter		Exposure Time
		0 h (fresh media)	24 h (old media)	24 h (fresh media)	48 h (old media)
Temperature (°C)		20.5	20.9	20.5	20.7
Oxygen concentration (mg/L)	control	8.3	8.9	8.3	8.4
	Test item (unfiltered)	7.8	8.7	7.9	8.3
	Test item (filtered)	7.0	8.6	7.2	8.5
pH	Control	7.61	7.43	7.11	7.17
	Test item (unfiltered)	7.65	7.53	7.24	7.27
	Test item (filtered)	7.70	7.55	7.147	7.25

 

DATA OF IMMOBILISATION

Immobilisation of the test animals

Test group	Number of animals	Number of immobilised animals
		24 h	48 h
Control	5	0	0
	5	0	0
	5	0	0
	5	0	0
100.0 mg/L nominal loading rate (unfiltered)*	5	0	0
	5	0	0
	5	0	0
	5	0	2
100.0 mg/L nominal loading rate (filtered)*	5	0	0
	5	0	0
	5	0	0
	5	0	0

*Remark: All of the animals got stuck at the surface of the unfiltered solution, but separated and swam after gentle agitation of the test beaker, they were not considered to be immobile (with the exception of two animals as shown above).

Validity criteria fulfilled:

yes

Conclusions:

Acute toxicity of SynNova Base Oil was assessed with Acute immobilisation test on Daphnia magna, over an exposure period of 48 hours in a semi-static system.
All validity criteria were met during this study.
Under the conditions of this Daphnia magna acute immobilisation study the observed endpoints for the effect of SynNova Base Oil were the followings:

Based on the nominal loading rate (WAF):
The 24h and 48h EL50 value: > 100.0 mg/L
The 48h EL100 value: > 100.0 mg/L
The 48h No-Observed Effect Loading Rate (NOELR): 100.0 mg/L
The 48h Lowest Observed Effect Loading Rate (LOELR): > 100.0 mg/L

Executive summary:

Acute toxicity of SynNova Base Oil on Daphnia magna was assessed in an Acute immobilisation test, over an exposure period of 48 hours in a semi-static test system.

 

Because no toxic response was observed during the preliminary range-finding test, a Limit Test was carried out using only one test concentration at 100 mg/L nominal loading rate (WAF) (a filtered and a non-filtered one in parallel) and one control group in the definitive test.

 

The WAF solution was prepared with direct addition of the test item. During the preparation periods, droplets in the top layers were observed in the test solution, so the solution in the middle layer was collected and siphoned into another test vessel as exposure solution, certainly, there no obvious droplets were observed in the exposure solution. Any remaining non-dissolved test chemical component in the WAF has the possibility to cause physical effects on the test organism unrelated to inherent chemical toxicity. For this reason, a filtered and a non-filtered test item group was tested in parallel to demonstrate that any effect observed is due to physical effects and not toxicity.

The test concentration was analytically determined at the start and at the end of the renewal periods. The measured concentration was below the Limit of Detection (LOD = 0.094 mg/L) in both the filtered and non-filtered test item groups during the whole experiment. The biological results are based on the nominal loading rate (WAF).

 

Twenty animals, divided into four groups (glass beaker) of five animals each were used at the test concentration and for the control.

 

All validity criteria were met during this study.

 

Under the conditions of this Daphnia magna acute immobilisation study the observed endpoints for the effect of SynNova Base Oil were the followings:

 

Based on the nominal loading rate (WAF):

 

The 24h and 48h EL50 value: > 100.0 mg/L

The 48h EL100 value: > 100.0 mg/L

The 48h No-Observed Effect Loading Rate (NOELR): 100.0 mg/L

The 48h Lowest Observed Effect Loading Rate (LOELR): > 100.0 mg/L

Description of key information

Based on the nominal loading rate (WAF):

The 24h and 48h EL50 value: > 100.0 mg/L

The 48h EL100 value: > 100.0 mg/L

The 48h No-Observed Effect Loading Rate (NOELR): 100.0 mg/L

The 48h Lowest Observed Effect Loading Rate (LOELR): > 100.0 mg/L

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC50

Effect concentration:

100 mg/L

Additional information

Acute toxicity of SynNova Base Oil on Daphnia magna was assessed in an Acute immobilisation test, over an exposure period of 48 hours in a semi-static test system.

 

The WAF solution was prepared with direct addition of the test item. During the preparation periods, droplets in the top layers were observed in the test solution, so the solution in the middle layer was collected and siphoned into another test vessel as exposure solution, certainly, there no obvious droplets were observed in the exposure solution. Any remaining non-dissolved test chemical component in the WAF has the possibility to cause physical effects on the test organism unrelated to inherent chemical toxicity. For this reason, a filtered and a non-filtered test item group was tested in parallel to demonstrate that any effect observed is due to physical effects and not toxicity.

The test concentration was analytically determined at the start and at the end of the renewal periods. The measured concentration was below the Limit of Detection (LOD = 0.094 mg/L) in both the filtered and non-filtered test item groups during the whole experiment. The biological results are based on the nominal loading rate (WAF).

 

Under the conditions of this Daphnia magna acute immobilisation study the observed endpoints for the effect of SynNova Base Oil were the followings:

Based on the nominal loading rate (WAF):

The 24h and 48h EL50 value: > 100.0 mg/L

The 48h EL100 value: > 100.0 mg/L

The 48h No-Observed Effect Loading Rate (NOELR): 100.0 mg/L

The 48h Lowest Observed Effect Loading Rate (LOELR): > 100.0 mg/L