Fatty acids, C12-14 (even numbered), methyl ester

Toxicity to soil macroorganisms except arthropods

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

toxicity to soil macroorganisms except arthropods: long-term

Type of information:

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

Adequacy of study:

key study

Justification for type of information:

Category justification document is attached in chapter 13.

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

28 d

Dose descriptor:

NOEC

Effect conc.:

>= 1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Remarks on result:

other: CAS 111-82-0

Reference 2

Endpoint:

toxicity to soil macroorganisms except arthropods: long-term

Type of information:

experimental study

Adequacy of study:

key study

Study period:

11 Oct 2012 - 05 Dec 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 222 (Earthworm Reproduction Test (Eisenia fetida/Eisenia andrei))

Deviations:

yes

Remarks:

Soil moisture of the solvent control and the test item concentration 500 mg/kg soil dw deviated by more than 10 % of the initial value at termination. Food was given on day 0 instead on day 1. Deviations were considered to have no impact on the study.

GLP compliance:

yes (incl. QA statement)

Remarks:

Staatliches Gewerbeaufsichtamt, Niedersachsen, Germany

Analytical monitoring:

no

Vehicle:

yes

Details on preparation and application of test substrate:

- Method of mixing into soil (if used): The respective test item amount was weighed out for each test item concentration, dissolved in acetone (2.5 mL per replicate) and mixed thoroughly with quartz sand (10 g per replicate). After complete evaporation of the solvent, the treated quartz sand was given to the artificial soil (2643 g). Additional 341 mL demineralised water was added to the artificial soil to adjust the humidity of the artificial soil to a moisture of 52 % of the maximum water holding capacity. Subsequently, the test medium was thoroughly mixed to ensure a homogeneous distribution and about 600 g soil dry weight was filled into each test vessel.
- Controls: Artificial soil moistened with demineralised water without test or reference item was used as control medium. Artificial soil with addition of quartz sand treated with acetone and moistened with demineralised water without test item was used as solvent control medium
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): Acetone
- Concentration of vehicle in test medium (stock solution and final test solution): 2.5 mL per replicate
- Evaporation of vehicle before use: yes

Test organisms (species):

Eisenia fetida

Animal group:

annelids

Details on test organisms:

TEST ORGANISM
- Common name: earthworm
- Source: Dr.U.Noack-Laboratorien
- Age at test initiation: 2 to 12 months, with clitellum. The difference of age did not deviate by more than 1 month. Synchronisation of the population was achieved by placing adult earthworms into breeding boxes and removing the adults after 4 weeks. Offspring from the remaining cocoons reached the adult age after 2 months at the earliest.
- Weight at test initiation (range): 0.32 - 0.60 g
- Feeding: The earthworms were fed with cattle manure during the first four weeks. At test start and at Day 28 the food was carefully mixed into the soil, on the other days food was placed on the soil surface.

ACCLIMATION
- Acclimation period: Earthworms were adapted to artificial soil two days prior to test start

HOMOGENITY OF GROUS:
The worms were washed with dechlorinated tap water and dried gently on a paper towel. The homogeneity of the population was checked by weighing the earthworms. After confirmation of homogeneity, groups of 10 earthworms (chosen by a randomised procedure) were weighed and introduced to each test vessel.

Study type:

laboratory study

Substrate type:

artificial soil

Limit test:

no

Total exposure duration:

8 wk

Remarks:

reproduction was followed for eight weeks, mortality and sublethal effects were followed for the first four weeks

Test temperature:

18 - 22 °C

pH:

6.40 - 6.87

Moisture:

25.4 - 28.9% of the maximum water holding capacity

Details on test conditions:

TEST SYSTEM
- Test container (material, size): Round plastic boxes with an inner diameter of 15.0 cm corresponding to a bottom surface area of 177 cm2 and a height of 14.0 cm. Transparent and perforated lids enabled sufficient gas exchanges as well as light input and prevented the test substrate from drying.
- Amount of soil or substrate: about 600 g soil dry weight
- No. of organisms per container (treatment): 10
- No. of replicates per treatment group: 4
- No. of replicates per control: 8
- No. of replicates per vehicle control: 8

SOURCE AND PROPERTIES OF SUBSTRATE (if soil)
- Composition (if artificial substrate):
5% Peat, air dried and finely ground
20% Kaolin, kaolinite content >30%
74% Air dried quartz sand (sand with >50% particle size of 0.05 - 0.2 mm)
0.30% Calcium carbonate (CaCO3) to achieve a pH of 6.0 ± 0.5

- Maximum water holding capacity (in % dry weigth): 50%
- Pretreatment of soil: Two days before experimental starting the artificial soil (23.5 kg) was pre-moistened by adding demineralised water (2115 g) to get a soil moisture of each 26 % of the maximal water capacity.
- Storage (condition, duration): Until test start the evaporation of water from the artificial soil was avoided by covering the soil.
- Moistening: Throughout the test the replicates were weighed weekly. Evaporated water was added to maintain the soil moisture which should not deviate by more than 10% of the initial value at the end of the test. Since the soil seemed to be too dry it was decided to add additional water to the test vessels

OTHER TEST CONDITIONS
- Photoperiod: 16 hours light, 8 hours dark
- Light intensity: 400 - 800 lx

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): mortality and biomass after 4 weeks, reproduction after 8 weeks

VEHICLE CONTROL PERFORMED: yes

Nominal and measured concentrations:

62.5, 125, 250, 500, and 1000 mg/kg soil dry weight (nominal)

Reference substance (positive control):

yes

Remarks:

Carbendazim

Duration:

28 d

Dose descriptor:

LOEC

Effect conc.:

> 1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

8 wk

Dose descriptor:

LOEC

Effect conc.:

> 1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Duration:

28 d

Dose descriptor:

LOEC

Effect conc.:

> 1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: biomass

Duration:

28 d

Dose descriptor:

NOEC

Effect conc.:

1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

8 wk

Dose descriptor:

NOEC

Effect conc.:

1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Duration:

28 d

Dose descriptor:

NOEC

Effect conc.:

1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: biomass

Details on results:

- Mortality at end of exposure period: none
- Total mass of adults at beginning of test:
34.7 g (80 worms, control)
34.8 g (80 worms, solvent control)
17.4 g (40 worms, 62.5 mg test item/kg dw soil)
16.1 g (40 worms, 125 mg test item/kg dw soil)
15.8 g (40 worms, 250 mg test item/kg dw soil)
14.4 g (40 worms, 500 mg test item/kg dw soil)
14.5 g (40 worms, 1000 mg test item/kg dw soil)
- Changes in body weigth of live adults (% of initial weight) at end of exposure period:
48.3 g (79 worms, control), 41.6 ± 5.08% (pooled for control and solvent control)
49.7 g (80 worms, solvent control), 41.6 ± 5.08% (pooled for control and solvent control)
26.0 g (40 worms, 62.5 mg test item/kg dw soil), 50.1 ± 4.08%
24.1 g (40 worms, 125 mg test item/kg dw soil), 49.4 ± 6.84%
24.3 g (40 worms, 250 mg test item/kg dw soil), 54.5 ± 6.72%
23.4 g (40 worms, 500 mg test item/kg dw soil), 62.5 ± 6.97%
25.8 g (40 worms, 1000 mg test item/kg dw soil), 79.2 ± 8.65%
- No. of offspring produced:
control: 185 ± 15.8
solvent control: 183 ± 38.6
62.5 mg test item/kg dw soil: 214 ± 43.1
125 mg test item/kg dw soil: 186 ± 39.9
250 mg test item/kg dw soil: 186 ± 43.3
500 mg test item/kg dw soil: 201 ± 18.2
1000 mg test item/kg dw soil: 148 ± 24.8
- Morphological abnormalities: none
- Behavioural abnormalities: none

Results with reference substance (positive control):

NOEC(reproduction, mortality, body weight) = 0.503 mg a.i./kg soil dw
LOEC(reproduction, mortality, body weight) = 1.26 mg a.i./kg soil dw
EC50(reproduction) = 0.628 mg a.i./kg soil dw

Reported statistics and error estimates:

Differences between the control and the solvent control were statistically analysed using t-tests. Since no significances occurred, both controls were pooled for further statistics. One Way Analysis of Variance (ANOVA) was carried out for the determination of statistically significant differences compared to the pooled control. A Normality Test and an Equal Variance Test were conducted prior running the ANOVA. P-values for both Normality and Equal Variance Test are 0.05. The Alpha-value for ANOVA test (acceptable probability of incorrectly concluding that there is a difference) is Alpha = 0.05.

Description of key information

NOEC (28 d) >= 1000 mg/kg dw for Eisenia fetida (OECD 222)

Additional information

No experimental data evaluating the toxicity of Fatty acids, C12-14 (even numbered), methyl esters (CAS No. 308065-15-8) to soil macroorganisms are available.

 

Therefore, toxicity data from a structurally related category member are used as read-across (methyl laurate (CAS No. 111-82-0)) in accordance with Regulation (EC) No. 1907/2006, Annex XI, 1.5. Both substances are fatty esters esterified with methanol, containing fatty acid components with C-chain lengths of C12 (CAS No. 111-82-0) and C12-14 (CAS No. 308065-15-8), respectively. The log Kow values of these substances (> 5) indicate a high adsorption potential to soil particles. Methyl laurate (CAS No. 111-82-0) exhibits the highest toxicity to aquatic organisms (Daphnia and algae) throughout the whole SCAE Me category, with EC50 and NOEC values < 1 mg/L. Therefore, methyl laurate is used as worst-case read across substance. Based on the above information and the fact that the target substance has a high content of C12 fatty acids (30-100%), the use of data from methyl laurate as read-across for Fatty acids, C12-14 (even numbered), methyl esters is considered justified.

 

The toxicity of methyl laurate (CAS No. 111-82-0) to earthworms was evaluated by Winkelmann (2013) in a test according to OECD 222, under GLP conditions. Eisenia fetida was exposed to the test substance for 56 days at a concentration of 1000 mg/kg dw (limit test). Mortality and growth were evaluated after 28 days whereas reproduction was evaluated after 56 days. After the exposure period, no effects on earthworm’s survival, reproduction or growth were observed, leading to a NOEC >= 1000 mg/kg dw.

 

Based on the results obtained for the structurally related category member (in accordance with Regulation (EC) No. 1907/2006, Annex XI, 1.5), it can be concluded that Fatty acids, C12-14 (even numbered), methyl esters (CAS No. 308065-15-8) will not exhibit toxicity to soil macroorganisms.