Soybean oil, maleated, ester with triethanolamine

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:

Experimental start date 02 May 2017 Experimental completion date 11 May 2017

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 Guidelines for Testing of Chemicals (April 2004) No 202 "Daphnia sp., Acute Immobilisation Test"

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

Method C.2 of Commission Regulation (EC) No. 440/2008

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

Physical state/Appearance: Clear amber viscous liquid

Purity: 100% product
Expiry Date: 24 June 2018
Storage Conditions: Room temperature in the dark

Analytical monitoring:

yes

Remarks:

The concentration of total organic carbon in the test preparations was verified by TOC analysis at 0 and 48 hours

Details on sampling:

The concentration of total organic carbon in the test preparations was verified by TOC analysis at 0 and 48 hours

Vehicle:

no

Details on test solutions:

Due to the low aqueous solubility and complex nature of the test item, for the purposes of the study the test medium was prepared as a Water Accommodated Fraction (WAF) of the test item using a 23-Hour stirring period followed by a 1-Hour standing period.

Test organisms (species):

other: The test was carried out using first instar Daphnia magna derived from in-house laboratory cultures.

Details on test organisms:

Adult daphnids were maintained in 150 mL glass beakers containing Elendt M7 medium (see Annex 2) in a temperature controlled room maintaining the water temperature at 18 to 22 °C. The lighting cycle was controlled to give a 16 hours light and 8 hours darkness cycle with
20 minute dawn and dusk transition periods. Each culture was fed daily with a mixture of algal suspension (Desmodesmus subspicatus) and Tetramin® flake food suspension. Culture conditions ensured that reproduction was by parthenogenesis. Gravid adults were isolated the day before initiation of the test, such that the young daphnids produced overnight were less than 24 hours old. These young were removed from the cultures and used for testing. The
diet and diluent water are considered not to contain any contaminant that would affect the integrity or outcome of the study.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

Not reported

Test temperature:

Temperature was maintained at 21 ºC to 22 ºC throughout the test

pH:

7.7 - 7.9 See Table 3 Water Quality Measurements

Dissolved oxygen:

8.2 to 8.7 See Table 3 Water Quality Measurements

Salinity:

N/A

Conductivity:

N/A

Nominal and measured concentrations:

Following a preliminary range-finding test, twenty daphnids (4 replicates of 5 animals) were exposed to Water Accommodated Fractions (WAFs) of the test item over a range of nominal loading rates of 1.0, 3.2, 10, 32 and 100 mg/L

Reference substance (positive control):

yes

Remarks:

A positive control (Envigo Study Number XT01HS) used potassium dichromate as the reference item. Details of the positive control are given in Annex 3. The positive control was conducted between 20 October 2016 and 22 October 2016

Key result

Duration:

48 h

Dose descriptor:

EL50

Remarks:

EL50 (mg/L Loading Rate WAF)

Effect conc.:

36 mg/L

Nominal / measured:

nominal

Conc. based on:

other: WAF

Basis for effect:

mobility

Remarks on result:

other: The test was considered to be valid

Remarks:

95% Confidence Limits (mg/L Loading Rate WAF) 25 - 53

Duration:

48 h

Dose descriptor:

other: NOEL

Remarks:

No Observed Effect Loading Rate (NOEL) (mg/L)

Effect conc.:

3.2 mg/L

Nominal / measured:

nominal

Conc. based on:

other: WAF

Basis for effect:

mobility

Remarks on result:

other: The test was considered to be valid

Details on results:

Total Organic Carbon (TOC) analysis of the test preparations at 0 hours showed measured concentrations to range from 1.02 to 16.91 mg C/L whilst concentrations in the range of less than the limit of quantification (LOQ), determined to be 1.0 mg C/L, to 51.65 mg C/L were obtained at 48 hours.

The dissolved test item may have been one or several components of the test item. Given that the toxicity cannot be attributed to a single component or a mixture of components, but to the test item as a whole, the results were based on nominal loading rates only.

Exposure of Daphnia magna to the test item gave the following results:


Time Point (Hours) EL50 95% Confidence Limits No Observed Effect Loading Rate Lowest Observed Effect Loading Rate
(mg/L Loading Rate WAF) (mg/L Loading Rate WAF) (NOEL) (mg/L) (LOEL) (mg/L)

48 36 25 - 53 3.2 10

Results with reference substance (positive control):

A positive control (Envigo Study Number XT01HS) used potassium dichromate as the reference item. Details of the positive control are given in Annex 3. The positive control was conducted between 20 October 2016 and 22 October 2016

Cumulative immobilization data and other observations from the exposure of Daphnia magna

to the test item during the range-finding test are given in Table 1.

 

No immobilization was observed at 1.0 mg/L loading rate WAF, however, immobilization was observed at 10 and 100 mg/L loading rate WAF. Daphnids covered in debris were observed in the 100 mg/L loading rate WAF vessels at both 24 and 48 hours.

 

Based on this information loading rates of 1.0, 3.2, 10, 32 and 100 mg/L were selected for the definitive test.

 

Total Organic Carbon (TOC) analysis of the test preparations at 0 hours showed measured concentrations to range from less than the limit of quantification, determined to be 1.0  

Definitive Test

Total Organic Carbon Analysis

Total Organic Carbon (TOC) analysis of the test preparations at 0 hours showed measured concentrations to range from 1.02 to 16.91 mg C/L whilst concentrations in the range of less than the limit of quantification (LOQ), determined to be 1.0 mg C/L, to 51.65 mg C/L were obtained at 48 hours (see Annex 4).

 

The dissolved test item may have been one or several components of the test item. Given that the toxicity cannot be attributed to a single component or a mixture of components, but to the test item as a whole, the results were based on nominal loading rates only.

 

Immobilization Data

Cumulative immobilization data and other observations from the exposure of Daphnia magna to the test item during the definitive test are given in Table 2. The relationship between percentage immobilization and concentration at 48 hours is given in the attached Figure 1.

 

Analysis of the immobilization data by Probit analysis using Linear Maximum-Likelihood regression at 24 and 48 hours based on the nominal loading rates gave the following results:

Time (h)	EL50 (mg/L Loading Rate WAF)	95% Confidence limits (mg/L Loading Rate WAF)
24	68	50 – 100
48	36	25 - 53

The No Observed Effect Loading rates after 24 and 48 hours exposure were 10 and 3.2 mg/L loading rate WAF respectively. Correspondingly the Lowest Effect Loading rates were considered to be 32 and 10 mg/L loading rate WAF.

 

The slopes and their standard errors of the response curves at 24 and 48 hours were

3.3 (SE = 0.070) and 2.4 (SE = 0.079) respectively.

 

Sub-Lethal Effects

 

A sub-lethal effect of exposure was observed in the 32 and 100 mg/L loading rate WAF cultures at 48 hours. This response was being covered in debris (see Table 2).

 

Microscopic examination of the immobilized daphnids at 24 hours showed there to be no abnormalities at 32 mg/L loading rate WAF, the immobilized daphnids in the 100 mg/L loading rate WAF vessels were observed to have debris and/or test item and a damaged carapace attached. Microscopic examination of the immobilized daphnids at 48 hours showed there to be no abnormalities at 10 mg/L loading rate WAF. The immobilized daphnids in the 32 mg/L loading rate WAF vessels were observed to be coated in debris and/or test item whilst those in the 100 mg/L loading rate WAF vessels were observed to have debris and/or test item and a damaged carapace attached.

 

Given these observations care should be taken in the interpretation of the results as it was not possible to determine whether the effects seen were due to a toxicological and/or physical effect.

 

Validation Criteria

 

The test was considered to be valid given that none of the control daphnids showed immobilization or other signs of disease or stress and that the oxygen concentration at the end of the test was equal to or greater than 3 mg/L in the control and test vessels.

 

Water Quality Criteria

 

The results of the water quality measurements are given in Table 3. Temperature was maintained at 21^oC to 22^oC throughout the test, while there were no treatment related differences for oxygen concentration or pH.

 

Throughout the test the light intensity was observed to be in the range 527 to 565 lux.

 

Vortex Depth Measurements

 

The vortex depth was recorded at the start and end of the mixing period and was observed to be a dimple at the water surface on each occasion.

 

Observations on Test Item Solubility

Observations on the test media were carried out during the mixing and testing of the WAFs. At both the start and end of the mixing period, and following a 1-Hour standing period, the

1.0 and 3.2 mg/L loading rate WAFs were observed to have formed clear colorless water columns with test item floating at the water surface. At the start and end of the mixing period, and following a 1-Hour standing period the 10, 32 and 100 mg/L loading rate WAFs were observed to have formed hazy non-homogenous dispersions, the opacity of which increased with increased loading rate.

 

Visual examination of the 10, 32 and 100 mg/L loading rate WAFs showed there to be dispersed test item present and hence it was considered necessary to remove the aqueous phase by filtration. Two glass wool plugs and two pieces of filter paper were used to remove as much dispersed test item as possible. After filtration, no micro-dispersions were observed in either the 1.0 or 3.2 mg/L loading rate WAFs. Visual examination of the 10, 32 and 100 mg/L loading rate WAFs showed dispersed test item remained however, it was considered that further filtration would not have removed any more of the undissolved material.

 

After filtration and for the duration of the test, the control, 1.0 and 3.2 mg/L loading rates were observed to be clear colorless solutions. The 10 mg/L loading rate was observed to be an extremely slightly hazy dispersion, the 32 mg/L loading rate was a slightly hazy dispersions whilst the 100 mg/L loading rate was a hazy dispersion.

Validity criteria fulfilled:

yes

Conclusions:

Exposure of the freshwater invertebrate Daphnia magna to the test item has been investigated and gave the following results:

Time Point (Hours) EL50 95% Confidence Limits No Observed Effect Loading Rate Lowest Observed Effect Loading Rate
(mg/L Loading Rate WAF) (mg/L Loading Rate WAF) (NOEL) (mg/L) (LOEL) (mg/L)

48 36 25 - 53 3.2 10

Executive summary:

A study was performed to assess the acute toxicity of the test item to Daphnia magna. The method followed was designed to be compatible with the OECD Guidelines for Testing of Chemicals (April 2004) No 202, "Daphnia sp., Acute Immobilisation Test" referenced as Method C.2 of Commission Regulation (EC) No. 440/2008.

 

Due to the low aqueous solubility and complex nature of the test item, for the purposes of the test, the test medium was prepared as a Water Accommodated Fraction (WAF).

 

Following a preliminary range-finding test, twenty daphnids (4 replicates of 5 animals) were exposed to Water Accommodated Fractions (WAFs) of the test item over a range of nominal loading rates of 1.0, 3.2, 10, 32 and 100 mg/L for 48 hours at a temperature of 21C to 22 C under static test conditions. The number of immobilized daphnia and any adverse reactions to exposure were recorded after 24 and 48 hours.

 

Total Organic Carbon (TOC) analysis of the test preparations at 0 hours showed measured concentrations to range from 1.02 to 16.91 mg C/L whilst concentrations in the range of less than the limit of quantification (LOQ), determined to be 1.0 mg C/L, to 51.65 mg C/L were obtained at 48 hours.

 

The dissolved test item may have been one or several components of the test item. Given that the toxicity cannot be attributed to a single component or a mixture of components, but to the test item as a whole, the results were based on nominal loading rates only.

 

Exposure of Daphnia magna to the test item gave the following results:

Description of key information

Exposure of the freshwater invertebrate Daphnia magna to the test item has been investigated and gave the following results:

Time Point (Hours)	EL50 (mg/L Loading Rate WAF)	95% Confidence Limits (mg/L Loading Rate WAF)			No Observed Effect Loading Rate (NOEL) (mg/L)	Lowest Observed Effect Loading Rate (LOEL) (mg/L)
48	36	25	-	53	3.2	10

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

36 mg/L

Additional information

A study was performed to assess the acute toxicity of the test item to Daphnia magna. The method followed was designed to be compatible with the OECD Guidelines for Testing of Chemicals (April 2004) No 202, "Daphnia sp., Acute Immobilisation Test" referenced as Method C.2 of Commission Regulation (EC) No. 440/2008.

 

Due to the low aqueous solubility and complex nature of the test item, for the purposes of the test, the test medium was prepared as a Water Accommodated Fraction (WAF).

 

Following a preliminary range-finding test, twenty daphnids (4 replicates of 5 animals) were exposed to Water Accommodated Fractions (WAFs) of the test item over a range of nominal loading rates of 1.0, 3.2, 10, 32 and 100 mg/L for 48 hours at a temperature of 21C to 22 C under static test conditions. The number of immobilized daphnia and any adverse reactions to exposure were recorded after 24 and 48 hours.

 

Total Organic Carbon (TOC) analysis of the test preparations at 0 hours showed measured concentrations to range from 1.02 to 16.91 mg C/L whilst concentrations in the range of less than the limit of quantification (LOQ), determined to be 1.0 mg C/L, to 51.65 mg C/L were obtained at 48 hours.

 

The dissolved test item may have been one or several components of the test item. Given that the toxicity cannot be attributed to a single component or a mixture of components, but to the test item as a whole, the results were based on nominal loading rates only.

 

Exposure of Daphnia magna to the test item gave the following results:

Time Point (Hours)	EL50 (mg/L Loading Rate WAF)	95% Confidence Limits (mg/L Loading Rate WAF)			No Observed Effect Loading Rate (NOEL) (mg/L)	Lowest Observed Effect Loading Rate (LOEL) (mg/L)
48	36	25	-	53	3.2	10