Glycerides, tallow sesqui-, hydrogenated, propoxylated

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

9 April to 5 July 2017 (experimental dates)

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Freshwater Alga and Cyanobacteria, Growth Inhibition Test)

Version / remarks:

2006

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Batch No.of test material: RL686/15 (Elementis Specialties)
- Expiration date of the lot/batch: 30 October 2018
- Purity test date: 11/11/2015

Analytical monitoring:

yes

Details on sampling:

- Concentrations: Control and 100% v/v saturated solution
- Sample storage conditions before analysis: Frozen

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Test substance heated to 40oC to aid weighing. Test sustance was dissolved in test media and stirred at approximately 15000 rpm for 24 hours. After 24 hours stirring was stopped and undissolved test substance removed by filtration (0.2 um Sartorius Sartopore filter
Eluate: Reconstituted culture medium (OECD)
- Differential loading: No
- Controls: Media control only
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): None
- Concentration of vehicle in test medium (stock solution and final test solution(s) or suspension(s) including control(s)): 100% v/v saturated solution
- Evidence of undissolved material (e.g. precipitate, surface film, etc.): No data

Test organisms (species):

Raphidocelis subcapitata (previous names: Pseudokirchneriella subcapitata, Selenastrum capricornutum)

Details on test organisms:

TEST ORGANISM
- Common name: Pseudokirchneriella subcapitiata
- Strain: CCAP 278/4
- Source (laboratory, culture collection): Master cultures maintained in laboratory. Orginal culture obtained from CCAP, SAMS Research Services Ltd, Scottish Marine Institute, Scotland, UK

ACCLIMATION
- Acclimation period: None

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

72 h

Hardness:

No data

Test temperature:

24 +/-1oC (niominal)

pH:

0h: 7.4-7.6
72h: 7.6

Dissolved oxygen:

No data

Salinity:

No data

Conductivity:

No data

Nominal and measured concentrations:

Nominal: Control and 100% v/v saturated solution
Measured:

Details on test conditions:

TEST SYSTEM
- Test vessel: Conical glass flask
- Type (delete if not applicable): Closed with polyurethane foam stoppers
- Material, size, headspace, fill volume: Glass conical flask with approximately 100 mL test solution
- Aeration: No
- Type of flow-through (e.g. peristaltic or proportional diluter): Not applicable
- Initial cells density: 5 x 10^3 cells/mL
- Control end cells density: 6.61 x 10^5 cells/mL
- No. of vessels per concentration (replicates): 6
- No. of vessels per control (replicates): 6

GROWTH MEDIUM
- Standard medium used: Yes

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: RO deionised water

OTHER TEST CONDITIONS
- Sterile test conditions: No
- Adjustment of pH: No
- Photoperiod: Continuous illumination
- Light intensity and quality: approx 7000 lux (warm white lighting)

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: [counting chamber; electronic particle counter; fluorimeter; spectrophotometer; colorimeter]

TEST CONCENTRATIONS
- Spacing factor for test concentrations: Limit test
- Justification for using less concentrations than requested by guideline: Limit test
- Range finding study
- Test concentrations: 0.1, 1.0, 10 and 100% v/v saturated solution
- Results used to determine the conditions for the definitive study: Yes

Reference substance (positive control):

yes

Remarks:

Conducted 28 November to 01 December 2016; results within normal range

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

>= 1.1 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Key result

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

>= 1.1 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

>= 1.1 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

biomass

Nominal concn (% v/v saturated solution)	Geometric mean measured concn (mg/L)		Growth rate		Yield (cells/mL)
			0-72h	% inhibition	0-72h	% inhibition
Control	<LoQ	Mean	0.068	-	6.54 x 10^5	-
		SD	0.0	-	1.21 x 10^4	-
100	1.1	Mean	0.065	5	5.22 x 10^5	20
		SD	0.001	-	1.24 x 10^4	-

Validity criteria fulfilled:

yes

Conclusions:

The 72-hour toxicity, based on growth rate, gave a 72-hour EC50 >1.1 mg/L (geometric mean measured concns) and a NOEC of 1.1 mg/L, although the test substance is not toxic to aquatic organisms at the limit of solubility, which is was less than the LoQ.

Executive summary:

In a 72-h toxicity study the green alga,Pseudokirchneriella subcapitata, was exposed to a single test concentration under static conditions in accordance with the OECD test guideline 201 and in compliance with GLP. The nominal test concentrations were a control and a 100% v/v saturated solution prepared at a nominal loading rate of 50 mg/L. The measured concentrations at 0 and 72-hour were 8.9 and below the LoQ (Limit of Quantification), respectively.

Under the conditions of the test, the EC50 was determined to be >1.1 mg/L based on geometric mean measured concentrations. The NOEC was calculated to be 1.1 mg/L. However, the test substance is not toxic to aquatic organisms at the limit of solubility, which is was less than the LoQ.

Description of key information

In a 72-h acute toxicity study the green alga, Pseudokirchneriella subcapitata, was exposed to a single test concentration under static conditions in accordance with the OECD test guideline 201 and in compliance with GLP. The nominal test concentrations were a control and a 100% v/v saturated solution prepared at a nominal loading rate of 50 mg/L. Under the conditions of the test, the EC50 was determined to be >1.1 mg/L based on geometric mean measured concentrations. The NOEC was calculated to be 1.1 mg/L. However, the test substance is not toxic to aquatic organisms at the limit of solubility, which is was less than the LoQ.

Key value for chemical safety assessment

EC50 for freshwater algae:

1.1 mg/L

EC10 or NOEC for freshwater algae:

1.1 mg/L