1,2,4,5,7,8-Hexoxonane, 3,6,9-trimethyl-, 3,6,9-tris(Ethyl and Propyl) derivatives (upper limit: 41% w/w; typical concentration: 38% w/w)

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Jan 2015

Reliability:

1 (reliable without restriction)

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

Samples were taken at the start of the test as well as after 24 hours in both old and new solutions and at the end of the test for each concentration and the control. 15 ml was pipetted directly to HPLC vials from centrifuge tubes for new solutions and from the test vessels for old solutions. Analysis took place as soon as possible after sampling. A cooled auto-sampler was used to minimize degradation that may occur prior to analysis.

Details on test solutions:

Test medium
The test medium was Dutch Standard Water (DSW), having a pH of approximately 8.2, and a conductivity between 550 and 650 μS/cm, containing per liter of de-ionized water: 200 mg of CaCl2•2H2O, 180 mg of MgSO4•7H2O, 100 mg of NaHCO3 and 20 mg of KHCO3. The guideline criteria requires the CaCO3 content to be between 10 and 250 mg/L (approximately 1-14 ºdH). Water hardness parameters are measured monthly in the DSW system using the appropriate Dr Lange test kit. These are validated by analyzing a CaCl2 Standard. The dilution water was saturated with oxygen before the start of the test.

Test solutions
The test material comprises of multiple components with different physical chemical properties. The active components are also of low solubility (AkzoNobel 2015). For this reason preparation of the test solutions in a standard manner via a stock solution and further dilution is not possible. For this reason WAF’s were prepared for each test concentration separately. This was achieved by accurate weighing of the test substance with an analytical balance and loading of the test material to 1 liter of test medium. The resulting solutions were stirred slowly for 48 hours. This was shown by preliminary studies sufficient to achieve the highest possible concentration of the measured active components. After 48 hours of slow stirring the solutions were stopped and allowed to rest for one hour. After which approximately 350 ml of liquid from each of the WAF vessels was tapped off into a centrifuge tube. The tap was positioned so as to remove liquid from the water phase of the vessel avoiding transfer of undissolved material on the surface or bottom of the vessels. Centrifugation then took place at 8000 RPM for 10 minutes so as to align the methodology with that of water solubility testing procedures. Furthermore this also reduces the chance of undissolved material in the form of a dispersion being transferred to the test. From the centrifuge vessels the test vessels were filled to approximately 50 ml with the use of a dispenser pipette. Prior to each concentration the pipette was primed with the corresponding WAF solution and discarded to reduce any possible adsorption to the apparatus. The test solutions were then ready for addition of test organisms or for physical chemical measurements. WAF’s were then restarted again for solution refreshment after 24 hours using the same procedures.

Test concentrations
Direct addition of the test material to 1 L of test medium was carried out to achieve the following test substance loadings:
5.2, 11.2 24.5 53.3 and 116.3 mg/L

Test organisms (species):

Daphnia magna

Details on test conditions:

Test conditions
The test was carried out in a temperature-controlled room. The test temperature was set at 20°C and the actual temperature should remain constant within ± 1°C. The light regime was 16 h of ambient light per day, provided by fluorescent tubes.

Test medium
The test medium was Dutch Standard Water (DSW), having a pH of approximately 8.2, and a conductivity between 550 and 650 μS/cm, containing per liter of de-ionized water: 200 mg of CaCl2•2H2O, 180 mg of MgSO4•7H2O, 100 mg of NaHCO3 and 20 mg of KHCO3. The guideline criteria requires the CaCO3 content to be between 10 and 250 mg/L (approximately 1-14 ºdH). Water hardness parameters are measured monthly in the DSW system using the appropriate Dr Lange test kit. These are validated by analyzing a CaCl2 Standard. The dilution water was saturated with oxygen before the start of the test.

Test procedures
The test was performed as a semi static test for 48 hours with refreshment after 24 hours. 20 animals divided into 4 batches of 5 animals were tested at each of 5 test concentrations and in the control. Those animals which are not able to swim within 15 seconds after gentle agitation of the test vessel are considered to be immobile. The number of animals being trapped at the surface was determined. These animals were not regarded as immobile and were made to re-submerge. Daphnids were randomly placed in the test fluids and the test vessels were placed in a random manner within each group. The test vessels were not aerated during the test and the animals were not fed. The test was inspected at 0, 24 and 48 hours and refreshed after 24 hours using identical procedures to those used at the start of the test.

Duration:

48 h

Dose descriptor:

EL50

Effect conc.:

> 116.3 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Validity criteria fulfilled:

yes

Conclusions:

The NOELR of the test material was determined as 116.3 mg/L a LOELR could not determined as no effects were observed. The EL50 may therefore be expressed as >116.3 mg/L.

Executive summary:

In order to predict the effects of the test substance in an aquatic environment, an acute immobilization test to Daphnia magna was conducted in accordance with OECD test guideline and with the OECD Principles of Good Laboratory Practice.

The toxicity of the test chemical to juvenile daphnids was determined in a semi-static system over an exposure period of 48 hours. Nominal loadings of 5.2, 11.2 24.5 53.3 and 116.3 mg/L were tested including the required control group.

The NOELR of the test material was determined as 116.3 mg/L a LOELR could not determined as no effects were observed. The EL50 may therefore be expressed as >116.3 mg/L. Use of the loading rate is not always fully acceptable to all regulatory authorities. In this case the test substance components can also be concluded to cause no toxicity to Daphnia magna at their corresponding maximum solubility limits in test medium i.e. the EC50 is > the limit of solubility of the test substance components.

It is preferable to express the toxicity as measured concentrations although for complex mixtures this is of debatable relevance. For this substance 2 of the 4 components could be detected and geometric mean exposure concentrations could be calculated. It is therefore also possible to express the endpoints as measured values expressed as total product quantified by each of the measured components. However due to the differing solubility of these components these measured values cannot be meaningfully related to the amount of total product for expression of the toxicity. The analytical data does however clearly demonstrate that each component was at or close to its water solubility limit in new test solutions. Hence the highest achievable initial concentration was tested. The following quality criteria have been met in the present study: · Immobilization in the control did not exceed 10% · Oxygen concentration did not fall below 3 mg/L at any point during the study · The EC50 value of the reference compound, potassium dichromate, was in the range of 0.25-2.0 mg/L (Documented as part of GLP laboratory maintenance). · No daphnids were irreversibly trapped on the surface for any length of time · Chemical analysis quality criteria were met The following quality criterion was not met in the present study: · The measured concentration s of the main components of the test chemical did not remain stable during the study.

The aim of the study was to determine a concentration at which 50% effect occurs in the test organism. Due to the soluble components of the test material not having any effect on the test organisms at a loading rate of 116.3 mg/L an EC50 could not be determined. For this reason only NOELR values or EL50 > values could be reported.

Reference 2

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

12/2/2013-14/2/2013

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Appropriate guideline followed with modifications for poorly soluble substances. No chemical analysis or GLP accreditation. Restricted for use as supporting evidence only.

Reason / purpose for cross-reference:

reference to other study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

yes

Principles of method if other than guideline:

Less replicates used, no chemical analysis, WAF method was used. Study is for screening purposes only.

GLP compliance:

no

Analytical monitoring:

no

Details on sampling:

N/A

Vehicle:

yes

Details on test solutions:

The test chemical is mixed with isoparaffinic hydrocarbons for stability and safety reasons and cannot be tested separately. The test material therefore needs to be tested in a manner that allows all of its ingredients or resulting degradation products / impurities the possibility to dissolve up to their solubility limit in the test media and thus assessing ecotoxicological effect of all of the components of the test chemical. For this reason a WAF approach was used for this test. WAF solutions at 1,10 and 100 mg/L were prepared as follows; accurately weighed amounts of test material (1 10 and 100 mg) were added to 1000 mL of DSW medium was added and agitated slowly with a magnetic stirrer at room temperature for 24 hours in a sealed glass vessel. The procedure was repeated for each WAF solution separately. After 24 hours each WAF was then considered loaded with the test substance.

Each WAF was left to stand for one hour after which the test solutions were extracted from the middle of the test vessels using a syringe and inert tubing. Due to the possibility of transferring undissolved test material the removed solutions were centrifuged at 800 RPM for 10 minutes and transferred in the same manner to the test vessels.


The test medium Dutch Standard Water (DSW, ref 7) was used for testing. DSW has a pH of 8.3, conductivity of 607µs/cm, and contains: 200 mg of CaCl2.2H2O, 180 mg of MgSO4.7H2O, 100 mg of Na.HCO3 and 20 mg of KHCO3 per liter. The water was made by an automatic dosing system and aerated before being used in the test.

Test organisms (species):

Daphnia magna

Details on test organisms:

The stock culture of the test animals aged between 2 and 4 weeks old was sieved 24 hours prior to starting the test to ensure all juvenile test animals were <24hours old. Daphnia Magna Clone 5 were used.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Remarks on exposure duration:

Demonstrated stable other studies.

Post exposure observation period:

None

Hardness:

Not measured

Test temperature:

20±1 ºC

pH:

7.7-7.9

Dissolved oxygen:

8.9-9.1

Salinity:

N/A

Nominal and measured concentrations:

1,10 and 100 mg/L Loading.

Details on test conditions:

The stock culture of the test animals aged between 2 and 4 weeks old was sieved 24 hours prior to starting the test to ensure all juvenile test animals were <24hours old. The test solutions were prepared as Water Accommodated Fractions in DSW as described below. pH and oxygen measurements were taken. The test solutions were then transferred to 50 mL beakers (open system). Two replicates of 5 animals were tested per test concentration and four replicates in the control. Observations were made at 0 24 and 48 hours. At the start and at the end of the test pH and oxygen concentrations
were measured

Duration:

48 h

Dose descriptor:

EL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: N/A

Duration:

48 h

Dose descriptor:

NOELR

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: N/A

Details on results:

Results demonstrate a lack of toxicity at the maximum achievable concentration in test medium.

Results with reference substance (positive control):

Conducted periodically as part of GLP maintenance.

Reported statistics and error estimates:

Not required no effects observed.

Concentration (mg/l)	Batches/Total
		Closed system
		0 hrs	24 hrs	48 hrs
Control	Batch I Batch II Batch III Batch IV Total	5 5 5 5 20	5 5 5 5 20	5 5 5 5 20
WAF 1 mg/L	Batch I Batch II Total	5 5 10	5 5 10	5 5 10
WAF 10 mg/L	Batch I Batch II Total	5 5 10	5 5 10	5 5 10
WAF 100 mg/L	Batch I Batch II Total	5 5 10	5 5 10	5 5 10

Validity criteria fulfilled:

yes

Remarks:

Valid as supporting evidence

Conclusions:

The test substance is not acutely toxic to daphnia magna at its maximum achievable concentration in the test medium. Analytical confirmation of stability had been demonstrated during chronic testing. Stabilization of the maximum water solubility of the parent material in a WAF preparation has bee demonstrated in GLP algae study on this material.

Executive summary:

Non GLP screening study to relevant guideline without chemical analysis and with adaptions for poorly water soluble substances. Valid as supporting evidence with the restrictions mentioned.

Reference 3

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

12-1997

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Test is valid and done under GLP however no analysis was performed and the content of the test concentration is unknown therefore the reliability has rstrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

yes

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

Daphnia magna

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Nominal and measured concentrations:

nominal 0.5, 1, 21 mg/L

Reference substance (positive control):

no

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 2 mg/L

Nominal / measured:

nominal

Conc. based on:

other: total solution

Basis for effect:

mortality

Validity criteria fulfilled:

yes

Conclusions:

Test is valid however no analysis was performed and the content of the test concentration is unknown

Reference 4

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

10-1997

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study done under GLP and complete

Qualifier:

according to guideline

Guideline:

other: OECD 202 and EU C.2 of 92/69/EEC

GLP compliance:

yes

Analytical monitoring:

yes

Vehicle:

yes

Details on test solutions:

Identity and concentration of auxiliary solvent for dispersal: Acetone

Test organisms (species):

Daphnia magna

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

CA 100 mg CaCO3/L

Test temperature:

21 C

pH:

7.7

Dissolved oxygen:

7.6-8.1 mg/L

Nominal and measured concentrations:

nominal 2 mg/L

Reference substance (positive control):

no

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 2 mg/L

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 2 mg/L

Duration:

48 h

Dose descriptor:

EC100

Effect conc.:

> 2 mg/L

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

>= 2 mg/L

Details on results:

%Concentration loss over test: 16 ...

Validity criteria fulfilled:

yes

Conclusions:

study is valid and complete, therefore the EC50 is determined to be > 2 mg/L

Description of key information

The results of an OECD 202 GLP study show that substance is not acutely toxic to Daphnia at maximum soluble concentration.

Additional information

The toxicity of the test chemical to juvenile daphnids was determined in a semi-static system over an exposure period of 48 hours. Nominal loadings of 5.2, 11.2 24.5 53.3 and 116.3 mg/L were tested including the required control group.

The NOELR of the test material was determined as 116.3 mg/L a LOELR could not determined as no effects were observed. The EL50 may therefore be expressed as >116.3 mg/L. Use of the loading rate is not always fully acceptable to all regulatory authorities. In this case the test substance components can also be concluded to cause no toxicity to Daphnia magna at their corresponding maximum solubility limits in test medium i.e. the EC50 is > the limit of solubility of the test substance components.