Fatty acids, C5-10, esters with pentaerythritol

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

29 Feb - 02 Mar 2007

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.3 (Algal Inhibition test)

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Water Accomodated Fraction (WAF): A concentration of 100 mg/L of the test substance was moderately stirred in algal medium for 24 h at
room temperature. After this incubation time, the undissolved materials were removed by sterile filtration (0.45 µm) to obtain a sterile test substance solution for the algal growth test. The resulting water accommodated fraction was used in the test.

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISM
- Strain: 86.81 SAG
- Source: obtained from the collection of Algal Cultures, Institute of Freshwater Ecology, University of Göttingen, Göttingen, Germany
Age of inoculum (at test initiation): Exponentially growing liquid preculture were used to inoculate sterile test flasks.
- Method of cultivation: 250 mL flask containing 100 mL of sterile OECD medium inoculated with cell material from axenic slope culture, continuous
illumination from warm white fluorescent tubes (8500 - 9000 lux), temperature: 22 ± 0.2 °C thermocontrolled room, periodically conducted
reference test with potassium dichromate.

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

72 h

Hardness:

not stated

Test temperature:

22 ± 0.2 °C

pH:

8.0 ± 0.2

Nominal and measured concentrations:

Nominal: 100 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Erlenmeyer flask
- Material: glass; Size: 250 mL; Fill volume: 100 mL
- Initial cells density: 10000 - 20000/mL
- No. of vessels per concentration: 3
- No. of vessels per control: 5

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: OECD medium
- Culture medium different from test medium: no
- Intervals of water quality measurement: Temperature was determined in a control flask at the start and at the end of the test. The pH was determined in 1 control flask after sterilization before the test and in all test vessels at the end of the test. Observations of mis-shapen cells and cell-debris were made after 24, 48 and 72 h test duration.

OTHER TEST CONDITIONS
- Photoperiod: continuous
- Light intensity and quality: warm white fluorescent tubes (8500-9000 lux)

EFFECT PARAMETERS MEASURED: Algal growth was recorded after 24, 48 and 72 h test duration.
- Determination of cell concentrations: using a spectrophotometer (680 nm wavelength). Aliquots of 5 mL were removed from each test
substance served as controls. The starting cell density was determined using a counting chamber.

Reference substance (positive control):

no

Key result

Duration:

72 h

Dose descriptor:

EL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: EL50 (24-72h)

Key result

Duration:

72 h

Dose descriptor:

EL0

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: EL0 (24-72h)

Key result

Duration:

72 h

Dose descriptor:

EL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Remarks on result:

other: EL50 (24-72h)

Key result

Duration:

72 h

Dose descriptor:

EL0

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Remarks on result:

other: EL0 (24-72h)

Details on results:

- Exponential growth in the control: yes
- Observation of abnormalities: no

At the WAF loading rate of 100 mg/L no inhibition with respect to algal growth rate and algal cell growth (area under growth curve) compared to the untreated controls were observed. The no-observed-effect concentration for growth rates (ErL0) and biomass production (EbL0) with respect to the loading rate was ≥ 100 mg/L. The EL50 -value was conducted as EL50 (24 -72 h). But the EL50 can also be stated as EL50 (72 h) > 100 mg/L for the algal growth rate and algal cell growth.

Table 1: Cell concentration (A680) in individual test cultures after 24, 48 and 72 h of exposure to the test material. ((b) = Mean absorbance (A680))

Nominal concentration [mg/L]	Code	Cell concentration (A680)
		0 h (b)	24 h	48 h	72 h
Control	A B C D E	0.008 0.008 0.008 0.008 0.008	0.033 0.038 0.038 0.036 0.040	0.228 0.222 0.208 0.212 0.233	0.685 0.733 0.676 0.624 0.694
100	A B C	0.008 0.008 0.008	0.040 0.038 0.044	0.224 0.207 0.207	0.700 0.631 0.675

 

Reference 2

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

21 Jul - 24 Aug 1995

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

GLP Guideline study with acceptable restrictions: The light intensity exceeded the guideline requirements of 3870 to 4730 lux. The intensity ranged from 4559 to 5118 lux during the study. This minor deviation is not believed to have had any adverse effects on the study.

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

yes

Remarks:

The light intensity exceeded the guideline requirements of 3870 to 4730 lux. The intensity ranged from 4559 to 5118 lux during the study.

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

- Concentrations: control; 1000 mg/L treatment
- Sampling method: Samples were removed from the treatment and the control on day 0 and at termination of the study.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Individual treatment solutions (WAF) were prepared by adding the appropriate amount of the test substance to 1 L of algal nutrient media. The vessels were closed with cotton gauze stoppers to minimize evaporation and/or volatilization.The solutions were mixed at ≤ 10% vortex on magnetic stirplates with Teflon coated stirbars for approx. 24 hours. The 1000 mg/L treatment solution appeared slightly cloudy with undissolved test material floating on the surface. All remaining treatment solutions appeared clear with undissolved test material floating on the surface. After mixing, the solutions were allowed to settle for approx. one hour before the WAFs were removed through the outlet at the bottom of the aspirator bottle.
- Evidence of undissolved material: Once prepared, no test substance insolubility was observed in the WAF solutions during the study.

Test organisms (species):

Scenedesmus capricornutum

Details on test organisms:

TEST ORGANISM
- Strain: 1648
- Source: cultured in the Environmental Toxicology and Chemistry Laboratory of Exxon Biomedical Sciences Inc. Initial strain provided by the Department of Botany, University of Texas
- Age of inoculum: Algae were taken from stock cultures in their log phase of growth (culture date: 19 Jul 1995).
- Method of cultivation: Algae are cultured in algal nutrient media prepared with distilled water and reagent grade chemicals. Culturesd were held at 24 ± 2 °C under continuous illumination.

ACCLIMATION
- Culturing media and conditions: same as test

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Remarks on exposure duration:

± 1 h

Hardness:

not stated

Test temperature:

22.8 ± 0.8 °C

pH:

7.4 (test inition)
8.7 - 9.0 (test end)

Nominal and measured concentrations:

Nominal: 1000 mg/L, 500 mg/L, 250 mg/L, 125 mg/L and 62.5 mg/L ( loading rate WAFs)

Details on test conditions:

TEST SYSTEM
- Test vessel: Erlenmeyer flask
- Type: closed with cotton gauze stoppers
- Material: glass; Size: 125 mL; Fill volume: 80 mL
- Initial cells density: 10000 cells/mL
- Control end cells density: 4300000 cells/mL
- No. of vessels per concentration: 4
- No. of vessels per control: 4
-other: Each test flask was placed on a shaker table (100 rpm) for the duration of the study to keep the algae in suspension and facilitate the transfer of carbon dioxide.

GROWTH MEDIUM
- Standard medium used: yes, according to guideline: EPA-600/9-78-018

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: reverse osmosis dialyzed well water
- Culture medium different from test medium: no
- Intervals of water quality measurement: Temperature was continuously monitored. The pH was measured on day 0 and at termination.

OTHER TEST CONDITIONS
- Sterile test conditions: yes
- Photoperiod: continuous illumination
- Light intensity and quality: 4599 - 5118 lux (provided by cool-white fluorescent bulbs; oscillation rate: 100 oscillations/min.)

EFFECT PARAMETERS MEASURED: Cell densities were monitored after 24, 48, 72 and 96 h test duration.
- Determination of cell concentrations: Turner filter fluorimeter

Reference substance (positive control):

no

Key result

Duration:

72 h

Dose descriptor:

NOELR

Effect conc.:

>= 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

(WAF)

Basis for effect:

growth rate

Key result

Duration:

72 h

Dose descriptor:

EL50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

(WAF)

Basis for effect:

growth rate

Details on results:

- Exponential growth in the control: yes
- Observation of abnormalities: no
- Unusual cell shape: no
- Colour differences: no
- Flocculation: no
- Adherence to test vessels: no
- Aggregation of algal cells: no

The TOC results indicate that the level of test substance in the WAF was at or near the level of organic carbon in the control. This result confirmes the low water solubility of the test substance (table 1). Therefore, the effect values are determined in relation to the nominal test substance concentration.

Table 1: Results of TOC analysis

Loading level [mg/L]	Total organic carbon [mg/L]*
	0 h	4 h
control	5.4 ± 0.5	5.5 ± 0.6
1000 mg/L	6.7 ± 0.7	4.2 ± 1.2

*: triplicate TOC measurements on each sample

Table 2: Mean cell concentrations

Loading level [mg/L]	Mean cell concentration [cells/mL]
	0 h	24 h	48 h	72 h	96 h
Control	1.0E4	2.6E4	2.1E5	1.3E6	4.3E6
62.5	1.0E4	2.5E4	1.6E5	9.1E5	3.6E6
125	1.0E4	2.6E4	1.8E5	1.1E6	3.8E6
250	1.0E4	2.5E4	1.7E5	1.0E6	3.7E6
500	1.0E4	2.8E4	2.0E5	1.2E6	3.6E6
1000	1.0E4	2.8E4	2.1E5	1.2E6	3.6E6

Reference 3

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

30 Jul - 03 Aug 2007

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

GLP - Guideline study, tested with the source substance Fatty acids, C16-18 (even numbered), esters with pentaerythritol (CAS 85116-93-4). According to the ECHA guidance document “Practical guide 6: How to report read-across and categories (March 2010)”, the reliability was changed from RL1 to RL2 to reflect the fact that this study was conducted on a read-across substance.

Qualifier:

according to guideline

Guideline:

EPA OPPTS 850.5400 (Algal Toxicity, Tiers I and II) (January 2012)

GLP compliance:

yes (incl. QA statement)

Remarks:

Staatliches Gewerbeaufsichtsamt Hildesheim

Analytical monitoring:

yes

Details on sampling:

- Concentrations: The highest loading level and control were analytically verified at the beginning and end of the test via GC-MS.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Water Accomodated Fraction (WAF): Stock solutions of 10, 30 and 100 mg/L were prepared by directly adding appropriate amounts of test substance to dilution water. The stock solutions were shaken with 20 rpm for 24 h at room temperature. After a separation phase of at least 30 min the WAF was taken from the homogenous liquid phase.

Test organisms (species):

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

Details on test organisms:

TEST ORGANISM
- Common name: Pseudokirchneriella subcapitata
- Strain: HINDAK
- Source: Sammlung von Algenkulturen (SAG), Pflanzenphysiologisches Institut der Universität Göttingen, Germany
- Age of inoculum: A three day old preculture was used as inoculum.
- Method of cultivation: Fresh stocks were prepared every month on Z-Agar. Light intensity was 35-70 µE/m2*s for 24 h per day. Nutrient
medium Z according to Lüttge et al. (1994) was used as culture medium.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Test temperature:

21.4 - 22.8

pH:

7.44 - 10.11

Nominal and measured concentrations:

Nominal: 10, 30 and 100 mg/L
Measured (100mg/L WAF): 108.3 µg/L at test start; 34.9 µg/L at test end
Measured (control): < limit of quantification

Details on test conditions:

TEST SYSTEM
- Test vessel: Erlenmeyer flasks
- Type: closed with cotton wool plugs
- Size: 250 mL; Fill volume: 100 mL
- Initial cells density: 5134 cells/mL
- Control end cells density: 2655237 cells/mL (mean of 6 values)
- No. of vessels per concentration: 3
- No. of vessels per control: 6

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Threefold concentrated medium of the OPPTS guideline (3xAAP medium)
- Intervals of water quality measurement: pH at the beginning and end, water temperature hourly, room temperature continously, light intesity prior to the test start

OTHER TEST CONDITIONS
- Sterile test conditions: yes
- Photoperiod: 24 hrs light
- Light intensity and quality: 66.5 µE/m2*s ± 10%

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: Chlorophyll-a-fluorescence excitation at 435 nm, emission at 685 nm. Each replicate was measured 6-fold,
value (flash) no. 3-6 were used for calculation.
The cell density was measured at the beginning of the test (after application) and every 24h.
- Other: At the start and the end of the incubation the cells were checked for unusual cell shape, colour differences in chloroplast morphology,
flocculation, adherence of algae to test containers and aggregation of alga cells.

TEST CONCENTRATIONS
- Range finding study
- Test concentrations: 1, 10 and 100 mg/L
- Results used to determine the conditions for the definitive study: yes, specific growth rate inhibition was 14% at 100 mg/l (nominal) and yield
inhibition 60% at 100 mg/l (nominal)

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Key result

Duration:

72 h

Dose descriptor:

EL10

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

(WAF)

Basis for effect:

growth rate

Key result

Duration:

72 h

Dose descriptor:

EL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

(WAF)

Basis for effect:

growth rate

Key result

Duration:

96 h

Dose descriptor:

EL10

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

(WAF)

Basis for effect:

growth rate

Key result

Duration:

72 h

Dose descriptor:

EL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

(WAF)

Basis for effect:

biomass

Key result

Duration:

72 h

Dose descriptor:

EL10

Effect conc.:

50.7 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

(WAF)

Basis for effect:

biomass

Remarks on result:

other: 39.0 - 70.2 mg/L

Key result

Duration:

96 h

Dose descriptor:

EL10

Effect conc.:

50.7 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

(WAF)

Basis for effect:

biomass

Remarks on result:

other: 39.0-70.2 mg/L

Details on results:

- Exponential growth in the control: Yes

Results with reference substance (positive control):

- Results with reference substance valid? Yes
- EC50: 0.86 (72h, growth rate), 0.46 (72h, cell number)

Reported statistics and error estimates:

EC10, EC20 and EC50 value of growth rate and yield inhibition after 96h were calculated by sigmoidal dose-response regression.
Calculation of confidence intervals EC10, EC20 and EC50 values were carried out using standard procedures according to Clopper and Pearson
(1934).

Table 1: Cell densities

Nominal loading level [mg/l]	Replicate No.	Cell densities [cells/ml]
		0 hours	24 hours	48 hours	72 hours	96 hours
100	1 2 3	5134 5134 5134	21575 21821 20140	87524 94391 110176	467614 517224 546539	1904254 1918604 1935004
	Mean	5134	21179	97364	510459	1919287
30	1 2 3	5134 5134 5134	19095 21534 20468	98409 109684 101074	550434 616854 541414	2804204 2625854 2463904
	Mean	5134	20366	103056	569567	2631321
10	1 2 3	5134 5134 5134	21268 21309 23687	136129 125059 90414	677124 821444 592254	2957954 2496704 2761154
	Mean	5134	22088	117201	696941	2738604
Control	1 2 3 4 5 6	5134 5134 5134 5134 5134 5134	18664 24322 17455 19997 21370 21678	93079 129159 95744 111939 103124 96769	646989 887454 708694 682044 798894 613369	2244554 2090804 2828804 2664804 3275704 2826754
	Mean	5134	20581	104969	722907	2655237

 

Table 2: Evaluation after 96 h

Nominal loading level [mg/L]	Replicate No.	Yield	Inhibition of yield [%]	Growth rate [d^-1]	Rate-related inhibition [%]
100	1 2 3	1899120 1913470 1929870	28.34 27.80 27.18	1.479 1.481 1.483	5.15 5.03 4.89
	Mean	1914153	27.77	1.481	5.02
30	1 2 3	2799070 2620720 2458770	-5,62 1.11 7.22	1.576 1.559 1.543	-1.06 0.00 1.02
	Mean	2626187	0.90	1.559	-0.01
10	1 2 3	2952820 2491570 2756020	-11.42 5.98 -4.00	1.589 1.547 1.572	-1.91 0.81 -0.81
	Mean	2733470	-3.15	1.569	-0.64
Control	1 2 3 4 5 6	2239420 2085670 2823670 2659670 3270570 2821620		1.520 1.502 1.578 1.563 1.615 1.578
	Mean	2650103		1.559

 

Reference 4

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Remarks:

3 substances are available for read across

Adequacy of study:

weight of evidence

Justification for type of information:

see the attached justification in section 13 for details

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

GLP compliance:

no

Key result

Duration:

72 h

Dose descriptor:

EL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: EL50 (24-72h)

Remarks:

2,2-bis[(octanoyloxy)methyl]butyl decanoate (CAS 11138-60-6)

Key result

Duration:

72 h

Dose descriptor:

EL0

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: EL0 (24-72h)

Remarks:

2,2-bis[(octanoyloxy)methyl]butyl decanoate (CAS 11138-60-6)

Key result

Duration:

72 h

Dose descriptor:

EL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Remarks on result:

other: EL50 (24-72h)

Remarks:

2,2-bis[(octanoyloxy)methyl]butyl decanoate (CAS 11138-60-6)

Key result

Duration:

72 h

Dose descriptor:

EL0

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Remarks on result:

other: EL0 (24-72h)

Remarks:

2,2-bis[(octanoyloxy)methyl]butyl decanoate (CAS 11138-60-6)

Key result

Duration:

72 h

Dose descriptor:

NOELR

Effect conc.:

>= 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

other: test mat. / WAF

Basis for effect:

growth rate

Remarks on result:

other: Mixed esters of pentaerythritol, technical grade, with isooctanoic acid and C8/10 fatty acids (CAS 189200-42-8)

Key result

Duration:

72 h

Dose descriptor:

EL50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

other: test mat. / WAF

Basis for effect:

growth rate

Remarks on result:

other: Mixed esters of pentaerythritol, technical grade, with isooctanoic acid and C8/10 fatty acids (CAS 189200-42-8)

Key result

Duration:

72 h

Dose descriptor:

EL10

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

other: test mat. (WAF)

Basis for effect:

growth rate

Remarks on result:

other: Fatty acids, C16-18, esters with pentaerythritol (CAS 85116-93-4)

Key result

Duration:

72 h

Dose descriptor:

EL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

other: test mat. (WAF)

Basis for effect:

growth rate

Remarks on result:

other: Fatty acids, C16-18, esters with pentaerythritol (CAS 85116-93-4)

Key result

Duration:

96 h

Dose descriptor:

EL10

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

other: test mat. (WAF)

Basis for effect:

growth rate

Remarks on result:

other: Fatty acids, C16-18, esters with pentaerythritol (CAS 85116-93-4)

Key result

Duration:

72 h

Dose descriptor:

EL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

other: test mat. (WAF)

Basis for effect:

biomass

Remarks on result:

other: Fatty acids, C16-18, esters with pentaerythritol (CAS 85116-93-4)

Key result

Duration:

72 h

Dose descriptor:

EL10

Effect conc.:

50.7 mg/L

Nominal / measured:

nominal

Conc. based on:

other: test mat. (WAF)

Basis for effect:

biomass

Remarks on result:

other: 39.0 - 70.2 mg/L

Remarks:

Fatty acids, C16-18, esters with pentaerythritol (CAS 85116-93-4)

Validity criteria fulfilled:

not applicable

Remarks:

read across

Conclusions:

The substance, CAS 68424-31-7 ; EC 270-291-9, is analogous to the substances to be read across to, in terms of basic form, and the degree of substitution of functional groups is not considered to effect the proposed read across for the endpoint of toxicity to aquatic algae and cyanobacteria. Based on the available information to read across to, the substance is not expected to be toxic upto the limit of solubility in water.

Description of key information

No toxic effects up to the limit of water solubility.

Additional information

In accordance to Regulation (EC) No. 1907/2006 Annex XI, 1.5 a read across to three structurally related category members, fatty acids, C8-10 mixed esters with dipentaerythritol, isooctanoic acid, pentaerythritol and tripentaerythritol (CAS 189200-42-8), fatty acids, C8-10 (even numbered), di-and triesters with propylidynetrimethanol (CAS 11138-60-6) and fatty acids, C16-18 (even numbered), esters with pentaerythritol (CAS-No. 85116-93-4) was conducted. This read-across is justified in detail in the overall summary (IUCLID chapter 6.1) and within the category justification in IUCLID Section 13. In this case of read-across, the best suited (highest degree of structural similarity, nearest physico-chemical properties) read-across substances were used for the assessment. The fatty acid chain length of C8 – C10 of the first two read-across substances are similar to those of the target substance. In addition, the first read-across substance fatty acids, C8-10 mixed esters with dipentaerythritol, isooctanoic acid, pentaerythritol and tripentaerythritol contains the same alcohol component, i.e. pentaerythritol, and is a tetra-ester. The final read across substance is a mono-tetraester containing a fatty acid chain length of C16 –C18, nevertheless it is significant as it pins the longer chain length end of the polyol esters category and shows that at this chain length no toxicity to algae is expected up to the limit of water solubility.

The first study with the read-across substance fatty acids, C8-10 mixed esters with dipentaerythritol, isooctanoic acid, pentaerythritol and tripentaerythritol (CAS 189200-42-8) was performed according to OECD 201 under GLP conditions (Febbo, 1995). The green algae Scenedesmus capricornutum was exposed to nominal concentrations of 62.5 mg/L, 125 mg/L, 250 mg/L, 500 mg/L and 1000 mg/L. The test solution was prepared by adding the appropriate amount of test substance with subsequent stirring and sampling of the aqueous portions (WAFs) through the outlet at the bottom of the vessels. No inhibition of growth of Scenedesmus capricornutum up to the limit of water solubility was observed resulting in an EL50 > 1000 mg/L (nominal). A NOELR of ≥ 1000 mg/L was determined based on effects on growth rate.

For the second read across substance fatty acids, C8-10 (even numbered), di-and triesters with propylidynetrimethanol (CAS 11138-60-6) a study conducted according to OECD 201 and GLP (Häner. 2007) as limit test is available. The green algae Desmodesmus subspicatus was exposed to a limit concentration of 100 mg/L (nominal). A water accommodated fraction (WAF) was prepared by stirring the test substance in algal medium for 24 h and removing undissolved materials by filtration. No inhibition of growth rate and effects on biomass were observed resulting in an EL50 > 100 mg/L.

The third read across study investigated the toxicity of fatty acids, C16-18 (even numbered), esters with pentaerythritol (CAS-No. 85116-93-4) to algae. This static algal growth inhibition test with Pseudokirchnerella subcapitata was conducted according to GLP, and EPA OPPTS 850.5400 (Algal Toxicity, Tiers I and II) determined an ErL50 and ErL10 (72h) of > 100 mg/L (WAF loading rate). It can be concluded that no toxicological effects on algae are expected up to the water solubility for this read-across substance.

Based on these results from structurally related read-across substances (in accordance to Regulation (EC) No 1907/2006 Annex XI, 1.5) which are characterized by a similar ecotoxicological profile, it can be concluded that pentaerythritol tetraesters of n-decanoic, n-heptanoic, n-octanoic and n-valeric acids (CAS 68424-31-7) will not exhibit effects to aquatic algae up to the limit of water solubility. As it can be seen in the data matrix of the category justification in section 13 and the overall endpoint summary IUCLID 6.1, all reliable data in the polyol esters category support this hazard assessment by showing a consistent pattern of results, i.e. no toxic effects were observed to aquatic algae or other aquatic organisms up to the limit of water solubility.