Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

Justification for grouping of substances and read-across

The short chain methyl esters category (SCAE Me) covers fatty acid esters of methanol. The category contains both mono-constituent substances, with fatty acid C-chain lengths ranging from C6 to C18 and UVCB substances, composed of single methyl esters in variable proportions. Fatty acid esters are generally produced by chemical reaction of an alcohol (e.g. methanol) with a fatty acid (e.g. lauric acid) in the presence of an acid catalyst (Radzi et al., 2005). The esterification reaction is started by the transfer of a proton from the acid catalyst to the acid to form an alkyloxonium ion. The carboxylic acid is protonated on its carbonyl oxygen followed by a nucleophilic addition of a molecule of the alcohol to the carbonyl carbon of the acid. An intermediate product is formed. This intermediate product loses a water molecule and proton to give an ester (Liu et al., 2006; Lilja et al., 2005; Gubicza et al., 2000; Zhao, 2000). Monoesters are the final products of esterification of fatty acids with methanol.

In accordance with Article 13 (1) of Regulation (EC) No 1907/2006, "information on intrinsic properties of substances may be generated by means other than tests, provided that the conditions set out in Annex XI are met.” In particular, information shall be generated whenever possible by means other than vertebrate animal tests, which includes the use of information from structurally related substances (grouping or read-across).

Having regard to the general rules for grouping of substances and read-across approach laid down in Annex XI, Item 1.5, of Regulation (EC) No 1907/2006, whereby substances may be considered as a category provided that their physicochemical, toxicological and ecotoxicological properties are likely to be similar or follow a regular pattern as a result of structural similarity, the substances listed below are allocated to the category of SCAE Me.

The SCAE Me category members include:

CAS

EC name

MW

Fatty acid chain length

Type of alcohol

Molecular formula

106-70-7 (a)

Methyl hexanoate

130.18

C6

Methanol

C7H14O2

111-11-5

Methyl octanoate

158.24

C8

Methanol

C9H18O2

110-42-9

Methyl decanoate

186.29

C10

Methanol

C11H22O2

111-82-0

Methyl laurate

214.35

C12

Methanol

C13H26O2

124-10-7 (b)

Methyl myristate

242.41

C14

Methanol

C15H30O2

112-39-0

Methyl palmitate

270.46

C16

Methanol

C17H34O2

112-62-9

Methyl oleate

296.49

C18:1 (cis)

Methanol

C19H36O2

112-63-0

Methyl linoleate

294.48

C18:2 (cis)

Methanol

C19H34O2

112-61-8

Methyl stearate

298.51

C18

Methanol

C19H38O2

68937-83-7

Fatty acids, C6-10, methyl esters

130.18-186.29

C6-10

Methanol

C7H14O2; C11H22O2

67762-39-4

Fatty acids, C6-12, methyl esters

130.18-214.35

C6-12

Methanol

C7H14O2; C13H26O2

85566-26-3

Fatty acids, C8-10, methyl esters

158.24-186.29

C8-10

Methanol

C9H18O2; C11H22O2

67762-40-7

Fatty acids, C10-16, methyl esters

186.29-270.46

C10-16

Methanol

C11H22O2; C17H34O2

61788-59-8

Fatty acids, coco, methyl esters

214.35-242.40

C12-14

Methanol

C13H26O2; C15H30O2

308065-15-8

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

214.35-242.40

C12-14

Methanol

C13H26O2: C15H30O2

1234694-02-0

Fatty acids, C12-16 (even numbered) and C18-unsatd., methyl esters

270.46-296.49

C16-18; C18uns.

Methanol

C17H34O2; C19H38O2; C19H36O2

68937-84-8

Fatty acids, C12-18, methyl esters

214.35-296.49

C12-18

Methanol

C13H26O2; C19H38O2

67762-26-9

Fatty acids, C14-18 and C16-18-unsatd., methyl esters

242.40-298.51

C14-18; C16-18uns.

Methanol

C15H30O2; C19H38O2; C17H32O2; C19H36O2

61788-61-2

Fatty acids, tallow, methyl esters

270.46-298.51

C16-18; C18:1

Methanol

C17H34O2; C19H38O2; C19H36O2

67762-38-3

Fatty acids, C16-18 and C18-unsatd., methyl esters

270.46-298.51

C16-18; C18uns.

Methanol

C17H34O2; C19H38O2; C19H36O2

85586-21-6

Fatty acids, C16-18, methyl esters

270.46–298.51

C16-18

Methanol

C17H34O2; C19H38O2

111-62-6 (c)

Ethyl oleate

310.52

C18:1 (cis)

Ethanol

C20H38O2

544-35-4 (c)

Ethyl linoleate

308.51

C18:2 (cis)

Ethanol

C20H36O2

68171-33-5 (c)

Isopropyl isostearate

326.56

C18iso

Iso-propanol

C21H42O2

123-95-5 (c)

Butyl stearate

340.60

C18

Butanol

C22H44O2

22047-49-0 (c)

2-ethylhexyl stearate

396.70

C18

2-ethyl-hexanol

C26H52O2

91031-48-0 (c)

Fatty acids, C16-18, 2-ethylhexyl esters

368.65-396.70

C16-18

2-ethyl-hexanol

C24H48O2; C26H52O2

57-10-3 (c)

Palmitic acid

256.43

C16

--

C16H32O2

(a) Category members subject to the REACh Phase-in registration deadline of 31 May 2013 are indicated in bold font. Only for these substances a full set of experimental results and/or read-across is given.

(b) Substances that are either already registered under REACh or not subject to the REACh Phase-in registration deadline of 31 May 2013 are indicated in normal font. Lack of data for a given endpoint is indicated by “--“.

(c)Surrogate substances are either chemicals forming part of a related category of structurally similar fatty acid esters or precursors/breakdown products of category members (i.e. alcohol and fatty acid moieties). Available data on these substances are used for assessment of (eco‑)toxicological properties by read-across on the same basis of structural similarity and/or mechanistic reasoning as described below for the present category.

 

Grouping of substances into this category is based on:

(1) common functional groups:

All category members are esters with the ester group being the common functional group of all substances. The substances are monoesters of aliphatic alcohols (methanol) and fatty acids with the chain length C6 to C18 and C18 unsaturated. The fatty acid chains comprise carbon chain lengths ranging from C6 (e.g. methyl hexanoate, CAS 106-70-7) to C18 (e.g. methyl stearate, CAS 112-61-8), mainly saturated but also mono and di unsaturated C18 (e.g. methyl oleate, CAS 112-62-9 and methyl linoleate, CAS 112‑63‑0).

(2) common precursors and the likelihood of common breakdown products via biological processes, which result in structurally similar chemicals:

All members of the category result from esterification of the alcohol with the respective fatty acid(s). Esterification is, in principle, a reversible reaction (hydrolysis). Thus, the alcohol and fatty acid moieties are simultaneously precursors and breakdown products of the category members. For the purpose of grouping of substances, enzymatic hydrolysis in the gastrointestinal tract and/or liver is identified as the biological process, by which the breakdown of the category members result in structurally similar chemicals. Following hydrolysis, fatty acids are enzymatically degraded primarily via beta-oxidation. Alternative oxidation pathways (alpha- and omega-oxidation) are available and are relevant for degradation of branched fatty acids. Unsaturated fatty acids require additional isomerization prior to enter the beta-oxidation cycle. The methanol is slowly oxidized in the liver by the enzyme alcohol dehydrogenase (ADH) to formaldehyde, which itself is oxidized very rapidly by the enzyme aldehyde dehydrogenase (ALDH) to formic acid. Finally, formic acid is slowly metabolised to CO2 and H2O (ICPS, 2002).

(3) constant pattern in the changing of the potency of the properties across the category:

a) Physicochemical properties:

The molecular weight of the category members ranges from 130.19 to 298.5 g/mol. The physical appearance is related to the chain length of the fatty acid moiety and the degree of saturation. Thus, methyl esters up to a fatty acid chain length of C12 are liquid, the C14 methyl ester (methyl myristate, CAS 124-10-7) is a semi solid substance, methyl esters with fatty acid chain lengths of C16 and C18 are solids (methyl palmitate and methyl stearate, CAS 112-39-0 and 112-61-8). Methyl esters with unsaturated fatty acids (C18:1, C18:2) are liquid (methyl oleate and methyl linoleate, CAS 112-62-9 and 112-63-0). For all category members the vapour pressure decreases with the chain length from 496 Pa (C6 methyl ester) to circa 0.002 Pa (C18 methyl ester), for C18 unsaturated esters it is even lower. The octanol/water partition coefficient increases with increasing fatty acid chain length, ranging from log Kow = 2.34 (C6) to log Kow = 8.35 (C18), for C18 unsaturated log Kow = 7.45 (C18:1) and 6.82 (C18:2) respectively. This trend can be observed also of the water solubility where 1330 mg/L for C6 methyl ester to 0.003 mg/L for C18 methyl ester is measured. The solubility of C18 unsaturated esters are slightly higher than for saturated components. It is observed that interactions between molecules of different single substances in water result in a decrease of water solubility comparing with water solubilities of mono-constituents, e.g. for C8-C10 it is 0.3 mg/L, while for C8 (64.4 mg/L) and for C10 (10.62 mg/L) can be found. Also for C10-C16 the value (<0.06 mg/L) is much closer to the lower value for C16 (0.004 mg/L) than to the C10 value of 10.62 mg/L, or C12 value of ca. 7.8 mg/L. It is generally concluded and experimentally confirmed that all UVCBs in the category are characterized with low water solubility (<1 mg/L).

b) Environmental fate and ecotoxicological properties:

The members of the SCAE Me category are readily biodegradable and show low bioaccumulation potential in biota. Hydrolysis is not a relevant degradation pathway for these substances, due to their ready biodegradability and estimated half-lives in water > 1 year at pH 7 and 8 (HYDROWIN v2.00). The majority of the SCAE Me category members have log Koc values > 3, indicating potential for adsorption to solid organic particles. Therefore, the main compartments for environmental distribution of these substances are expected to be soil and sediment, with the exception of methyl hexanoate (CAS 106-70-7) and methyl octanoate (CAS 111-11-5), for which log Koc < 3 are reported. Therefore, these two substances will be most likely available in the water phase. Nevertheless, all substances are readily biodegradable, indicating that persistency in the environment is not expected. The vapour pressure values of methyl hexanoate and methyl octanoate (> 10 Pa) indicate potential for volatilization of these substances into air. But if released into the atmosphere both these substances are susceptible to indirect photodegradation, with half-lives of 81.6 h and 51 h, respectively (AOPWIN v1.92). This degradation pathway is not relevant for all other category members, since their vapour pressure values are low (0.0001 Pa-4.93 Pa) and no significant release into the atmosphere is expected. Regarding the aquatic toxicity profile in the category, the LC50 values reported show that fish species are the least sensitive aquatic organisms when exposed to the SCAE Me category members. On the other hand, aquatic invertebrates and algae showed the highest sensitivity to these substances. A trend in the toxicity of the monoconstituent substances of the SCAE Me category to aquatic invertebrates and algae is observed, related to the toxicity mode of action (narcosis). The toxicity increases at increasing fatty acid C-chain length (starting from C6 (CAS 106-70-7)) up to a toxicity peak at C12 (for which L(E)C50s and NOECs < 1 mg/L have been reported). With decreasing water solubility at longer C-chain lengths (C14), no toxicity up to the highest attainable concentration is observed in Daphnia and algae. Based on the available data, no toxicity to aquatic microorganisms and terrestrial organisms is to be expected for the substances of the SCAE Me category.

c) Toxicological properties:

The toxicological properties indicate that all the category members show similar toxicokinetic behaviour. The ester bond will be hydrolysed in the gastrointestinal tract before absorption and the breakdown products will be metabolised. Based on the available data, none of the category members caused acute oral, dermal or inhalation toxicity, or skin or eye irritation, or skin sensitisation. No treatment-related effects were noted up to and including the limit dose of 1000 mg/kg bw/day after repeated oral exposure, indicating that the category members have a very limited potential for toxicity. The substances did not show a potential for toxicity to reproduction, fertility and development. No mutagenic or clastogenic potential was observed.

 

The available data allows for an accurate hazard and risk assessment of the category and the category concept is applied for the assessment of environmental fate, environmental and human health hazards. Thus where applicable, environmental and human health effects are predicted from adequate and reliable data for source substance(s) within the group by interpolation to the target substances in the group (read-across approach) applying the group concept in accordance with Annex XI, Item 1.5, of Regulation (EC) No 1907/2006. In particular, for each specific endpoint the source substance(s) structurally closest to the target substance is/are chosen for read-across, with due regard to the requirements of adequacy and reliability of the available data. Structural similarities and similarities in properties and/or activities of the source and target substance are the basis of read-across.

A detailed justification for the grouping of chemicals and read-across is provided in the technical dossier (see IUCLID Section 13).

 

Table 2. Aquatic toxicity parameters of the SCAE Me category

CAS

Short term toxicity to fish

Long term toxicity to fish

Short term toxicity to aquatic invertebrates

Long term toxicity to aquatic invertebrates

Toxicity to aquatic algae

Toxicity to microorganisms

106-70-7 (a)

Experimental result:
WoE

LC50 (48 h)

170 mg/L
RA: CAS 111-82-0
RA: CAS 111-11-5
RA: CAS 110-42-9

Waiving based on CSA

Experimental result:

EC50 (48 h)

40 mg/L

(nominal)

28 mg/L

(measured)

RA:CAS 111-11-5

Experimental result:

EC50 (72 h)

61 mg/L (nominal)

11 mg/L

(measured)

NOEC (72 h)

12.5 mg/L

(nominal)

2.7 mg/L

(measured)

RA:CAS 111-82-0

111-11-5

Experimental result:
WoE

LC50 (48 h)

>100-<300 mg/L
RA: CAS 110-42-9
RA: CAS 111-82-0
RA: CAS 106-70-7

Waiving based on CSA

(Q)SAR:
LC50 (48 h)

5.6 mg/L

Ongoing study

 

(Q)SAR:
EC50 (96 h)

4.76 mg/L

RA:CAS 111-82-0

110-42-9

Experimental result:
WoE

LC50 (48 h)

1700 mg/L
RA: CAS 106-70-7
RA: CAS 111-11-5
RA: CAS 111-82-0

Waiving based on CSA

Experimental result:
EC50 (48 h)

1.1 mg/L (meas.)

RA: CAS 111-82-0

Experimental result:
EC50 (72 h)

>0.055 mg/L (meas.)

RA:CAS 111-82-0

111-82-0

Experimental result:

LC50 (96 h)

>1 mg/L (nom.)
>0.52 mg/L (meas.)

Waiving based on CSA

Experimental result:
EC50 (48 h) 0.255 mg/L (meas.)

Experimental result:
NOEC (21 d) 0.0814 mg/L (meas.)

Experimental result:
EC50 (72 h)

0.324 mg/L (meas.)

NOEC (72 h)
0.0396 mg/L (meas.)

Experimental result:

NOEC (3 h)

1000 mg/L

124-10-7 (b)

Experimental result:
LC50 (96 h)

1700 mg/L (nom.)

--

Experimental result:
EC50 (48 h)

> 100 mg/L (nom.)

>0.02 mg/L (meas.)

--

Experimental result:
EC50 (72 h)

> 100 mg/L (nom.)

>0.023 mg/L (meas.)
NOEC (72 h)

100 mg/L (nom.)

0.023 mg/L (meas.)

--

112-39-0

Experimental result:
LC50 (96 h)

550 mg/L (nom.)

Waiving based on CSA

RA: CAS 124-10-7

RA: CAS 57-10-3

RA: CAS 124-10-7

RA:CAS 111-82-0

112-61-8

--

--

RA: CAS 124-10-7
RA: CAS 67762-26-9

--

RA: CAS 124-10-7

--

85566-26-3

Experimental result:
LC50 (96 h)

100 mg/L

Waiving based on CSA

RA: CAS 110-42-9
RA: CAS 111-11-5

Waiving based

on CSA

RA: CAS 110-42-9
RA: CAS 111-11-5

Waiving based

on CSA

61788-59-8

Experimental result:
LC50 (48 h)

55 mg/L (nom.)

--

--

--

--

--

308065-15-8

RA: CAS 111-82-0
RA: CAS 124-10-7

Waiving based on CSA

RA: CAS 111-82-0
RA: CAS 124-10-7

RA: CAS 111-82-0

RA: CAS 111-82-0
RA: CAS 124-10-7

RA: CAS 111-82-0

1234694-02-0

RA: CAS 68937-84-8

Waiving based on CSA

Experimental result:
EL50(48 h)

>0.16 mg/L (meas.)

RA: CAS 111-82-0

RA: CAS 111-82-0

RA: CAS 111-82-0

68937-84-8

Experimental result:
LC50 (96 h)

550 mg/L (nom.)

--

RA: CAS 111-82-0

RA: CAS 111-82-0

RA: CAS 111-82-0

--

67762-26-9

--

--

Experimental result:
EC50/EL50 (48 h)

>100 mg/L (nom.)

--

--

--

67762-38-3

Experimental result:
LC50 (48 h)

5500 mg/L (nom.)

--

Experimental result:
EL50(48 h)

>1000 mg/L (nom.)

--

--

--

85586-21-6

RA: CAS 112-39-0
RA: CAS 67762-38-3

Waiving based on CSA

RA: CAS 124-10-7
RA: CAS 67762-26-9
RA: CAS 67762-38-3

RA: CAS 57-10-3

RA: CAS 124-10-7

RA: CAS 111-82-0

57-10-3(c)

--

--

--

Experimental result:
NOEC (21 d) ≥ 0.22 mg/L (meas.)

--

--

(a) Category members subject to the REACh Phase-in registration deadline of 31 May 2013 are indicated in bold font. Only for these substances a full set of experimental results and/or read-across is given.

(b) Substances that are either already registered under REACh or not subject to the REACh Phase-in registration deadline of 31 May 2013 are indicated in normal font. Lack of data for a given endpoint is indicated by “--“.

(c)Surrogate substances are either chemicals forming part of a related category of structurally similar fatty acid esters or precursors/breakdown products of category members (i.e. alcohol and fatty acid moieties). Available data on these substances are used for assessment of (eco‑)toxicological properties by read-across on the same basis of structural similarity and/or mechanistic reasoning as described below for the present category.

 

In accordance with Regulation (EC) No. 1907/2006, Annex XI, 1.5, the toxicity of the SCAE Methyl Esters category members follows a trend for aquatic invertebrates and algae. No or only low toxicity is expected for fish species exposed to these substances. All category members are structurally similar and read-across was performed to the structurally most similar category members to fulfil the data requirements under Regulation (EC) No. 1907/2006. 

A trend in the toxicity of the monoconstituent substances of the SCAE Me category to aquatic invertebrates is observed, related to the toxicity mode of action (narcosis). Eight short-term toxicity tests conducted on aquatic invertebrates are available. The highest toxicity was determined for methyl laurate (CAS 111-82-0, fatty acid chain length C12). In a GLP-study conducted on this substance according to OECD 202, the EC50 (48 h) was determined to be 0.255 mg/L for Daphnia magna. The toxicity decreases with shorter fatty acid C-chain length (CAS 110-42-9, C10, EC50 (48 h)= 1.1 mg/L (Daphnia magna);CAS 111-11-5, C8, EC50 (48 h)= 5.6 mg/L (QSAR), CAS 106-70-7, C6, EC50 (48 h)= 28 mg/L (Daphnia magna)); and longer chain length (CAS 124-10-7, C14, EC50 (48 h) > 0.02 mg/L (Daphnia magna)). Due to the very low water solubility values of fatty acid C-chain lengths ≥ C14 (0.05-0.0003 mg/L), concentration levels that might be toxic for aquatic invertebrates could not be reached. Test results are available as well for two UVCB substances containing C14-18 and C16-18 unsatd. fatty acids (CAS 67762-26-9) with EL50 and EC50 (48 h) > 100 mg/L (nominal), and C16-18 and C18 unsatd. fatty acids (CAS 67762-38-3) with an EL50 (48 h) > 1000 mg/L (nominal). These results indicate that no toxicity of SCAE Me category members with fatty acid C-chain lengths > C14 to aquatic invertebrates is expected within the range of their water solubility. The toxicity to aquatic invertebrates of the remaining UVCB substances has been determined by read-across from the most similar monoconstituent or UVCB substances.

The same toxicity trend as observed in aquatic invertebrates can be observed in algae. This is related to the toxicity mode of action (narcosis). The highest toxicity to algae was determined for methyl laurate (CAS 111-82-0, fatty acid chain length C12). In the GLP-study conducted on this substance according to OECD 201 the EC50 (72 h, growth rate) was determined to be 0.324 mg/L (Pseudokirchneriella subcapitata). The toxicity decreases with shorter chain length (CAS 110-42-9, C10, EC50 (96 h)= 1.35 mg/L (QSAR) and EC50 (72 h) > 0.055 mg/L (Pseudokirchneriella subcapitata);CAS 111-11-5, C8, EC50 (96 h)= 4.76 mg/L (QSAR); CAS No. 106-70-7, C6, EC50 (72 h)= 11 mg/L and QSAR EC50 (96 h)= 16.2 mg/L. Estimated QSAR values obtained for methyl hexanoate (CAS 106-70-7 (C6)) and methyl decanoate (CAS 110-42-9 (C10)) are in agreement with experimental values, supporting the validity of the observed trend (reduced toxicity from C12 at lower C-chain lengths). A decrease in algal toxicity is observed also at longer fatty acid C-chain lengths (≥ C14)(CAS 124-10-7, C14, EC50 (48 h) > 0.023 mg/L (Pseudokirchneriella subcapitata)). Due to the very low water solubility values of fatty acid C-chain lengths ≥ C14 (0.05-0.0003 mg/L), and considering the test results for C14, no toxicity of these substances to algae in the range of their water solubility is expected. The toxicity of the UVCB substances to algae has been determined by read-across from the most similar monoconstituent substances.

Ten acute toxicity tests performed on fish species according to OECD/ internationally accepted guidelines are available for the SCAE Me category members. The results obtained in the studies conducted with methyl octanoate (CAS 111-11-5), methyl decanoate (CAS 110-42-9), methyl myristate (CAS 124-10-7), methyl palmitate (CAS 112-39-0), Fatty acids, C8-10, methyl esters (CAS 85566-26-3), Fatty acids, coco, methyl esters (61788-59-8), Fatty acids, C12-18, methyl esters (CAS 68937-84-8) and Fatty acids, C16-18 and C18-unsatd., methyl esters (CAS 67762-38-3) showed effects well above the water solubility of the respective substances (LC50 values > 50 mg/L (nominal)). Therefore, and especially regarding the most insoluble substances, these effects could be physical (due to direct interference with the test substances) rather than toxicological. The key study conducted on methyl laurate (CAS 111-82-0), with the aid of a solvent, reported no effects at the tested study concentration (LC50 (96 h) > 0.52 mg/L (measured concentration)). On the other hand, in the study performed with methyl hexanoate (CAS 106-70-7) effects within the water solubility of the substance were observed (LC50 (48)= 170 mg/L (nominal)). Nevertheless, the LC50 values reported in all the tests mentioned above show that fish species are the least sensitive aquatic organisms when exposed to the SCAE Me category members.

Regarding chronic data, two studies are available evaluating the toxicity of the SCAE Methyl Esters to aquatic invertebrates. The study conducted on methyl laurate (CAS 111-82-0, C12 fatty acid chain length) reported toxicity to aquatic life with long lasting effects for Daphnia magna after 21 days, with a NOEC = 0.0814 mg/L (mean measured concentration). Due to the metabolism of fatty acid methyl esters to the corresponding alcohol (methanol) and fatty acids, chronic data from palmitic (C16) acid (CAS 57-10-3) is considered as a valid read-across for the SCAE Methyl ester with longer fatty acid C-chain lengths (> C14). In the long-term study (limit-test) conducted with this substance on Daphnia magna according to OECD 211, no effects in survival or reproduction were observed, resulting in a NOEC ≥ 0.22 mg/L (measured TWA concentration). These results are in line with the toxicity trend observed in the acute aquatic invertebrates tests (high toxicity for C12 (CAS 111-82-0) and no toxicity for long fatty acid C-chain lengths (> C14)). An additional test performed according to OECD 211 is currently ongoing for methyl octanoate (CAS 111-11-5, C8). Once the results of this test become available, the chemical safety assessment according to Annex I of Regulation (EC) No. 1907/2006 will be re-evaluated for this substance based on the outcome of this new study, and the category justification will be updated as soon as possible.

Due to the availability of chronic NOEC values for the most sensitive species within the category (aquatic invertebrates and algae), long-term toxicity data on fish species is not deemed necessary for further assessment.

Due to the ready biodegradability of the SCAE Methyl esters, no toxicity could be expected for microorganisms and the inhibition of the biodegradation activity of activated sludge is not anticipated. One study (OECD 209) evaluating the toxicity of methyl laurate (CAS 111-82-0) to aquatic microorganisms is available (Fiebig, 2013), in which no inhibiting effects of the substance to microorganisms activity were reported, leading to a NOEC (3 h) ≥ 1000 mg/L (nominal concentration). Considering that methyl laurate exhibits the highest toxic potential to aquatic organisms, its lack of toxicity in the OECD 209 and the ready biodegradation studies, give a good indication of the expected lack of toxicity of the SCAE Me category members to activated sludge microorganisms.

A detailed reference list is provided in the technical dossier (IUCLID, section 13) and within CSR.