1-Propanaminium, 3-amino-N-(carboxymethyl)-N,N-dimethyl-, N-C8-10 (even numbered) acyl derivs., hydroxides, inner salts

Endpoint summary

Additional information

For the target substance C8-10 Alkylamidopropyl betaine, a short-term toxicity study with fish (Danio rerio) is available. Short-term toxicity tests to aquatic invertebrates, toxicity test to algae as well as long-term toxicity tests to fish and aquatic invertebrates are available for closely related source substances. A justification for read-across is given below.

 

Short-term toxicity to fish

In a 96 h acute toxicity study according to OECD guideline 203, adopted 17 July 1992, zebrafish (Danio rerio) were exposed to C8-10 Alkylamidopropyl betaine at nominal concentrations of 0 (control) and 100 mg/L under semi-static conditions in natural river water containing 3.46 mg/L TOC (2.71 mg/L DOC). Measured test item concentrations were in agreement with nominal (99-108%). These concentrations remained stable during both renewal periods. Given these results, effect parameters can be based on the nominal test concentrations.

No mortality or other clinical effect was observed at the limit concentration and the control during the 96-hour test period. The 96 h LC50 was >100 mg a.i./L. 

 

Similar results were obtained with the closely related read-across substances C8-18 and C18 unsatd. AAPB, C8-18 AAPB and Formamidopropylbetaine:

 

The acute toxicity of C8-18 and C18 unsatd. AAPB to fish (Pimephales promelas) was investigated in a study conducted according to OECD Guideline 203 and EU Method C.1. A 96 h LC50=1.11 mg a.i./L nominal (=3.7 mg product/L) was determined.

 

In a 28-d toxicity study conducted according to OECD Guideline 204 under flow-through conditions and using rainbow trouts (Oncorhynchus mykiss) as test organism, the 28-d NOEC and LOEC of C8-18 AAPB were 0.16 and 0.5 mg a.i./L nominal based on mortality and sublethal effects.

 

Formamidopropylbetaine induced no visible effects in carp at 100 mg/L (NOEC). The 96h-LC50 was> 100 mg/L based on analytically confirmed nominal concentrations.

 

The LC50 values obtained with the source substances C8-18 AAPB and C8-18 and C18 unsatd. AAPB in fish were lower than for the target substance. Fish was the most sensitive trophic level. Thus, the results from the studies with aquatic invertebrates and algae obtained with the source substances C8-18 AAPB and C8-18 and C18 unsatd. AAPB are considered to be also protective for these trophic levels.

 

Long-term toxicity to fish

In a study conducted according to OECD Guideline 210 (Fish, Early-Life Stage Toxicity Test) and EPA OPPTS 850.1400 (Fish Early-life Stage Toxicity Test), the 100 day chronic toxicity of C8 -18 AAPB to early life stage of rainbow trout (Oncorhynchus mykiss) was investigated under flow through conditions and analytical monitoring of test material concentrations. The mean recovery rates for all concentrations were in the range of 81 – 100 %. Therefore all effect values are based on nominal concentrations.

Fertilized eggs (4 x 35 eggs) were exposed to control and nominal concentrations of 0.005, 0.015, 0.045, 0.135, 0.405 and 1.215 mg active substance/L. The test system was maintained at 10 +/- 2 ºC (for eggs) and 12 +/- 2 °C (for larvae) and a pH of 7.48 to 7.66. The 37 – day NOEC and LOEC values, based on egg hatch, were 0.135 and 0.405 mg a.i./L respectively. The 100– day overall NOEC and LOEC values were 0.135 and 0.405 mg a.i./L, respectively. The effects included were length, dry weight, morphological and behavioural effects, post hatch success and overall survival.

 

Supporting data are available from a prolonged fish test: In a 28-d toxicity study conducted according to OECD Guideline 204, rainbow trouts (Oncorhynchus mykiss) were exposed to C8 -18 AAPB at nominal concentrations of 0.016, 0.05, 0.16, 0.5 and 1.6 mg a.i./L (= 0.05, 0.16, 0.50, 1.6 and 5.0 mg/L product (nominal)) under flow through conditions.  The 28-d NOEC and LOEC were 0.16 and 0.5 mg a.i./L nominal based on mortality and sublethal effects. The validity criteria of the OECD Guideline 204 were fulfilled.

 

Short-term toxicity to aquatic invertebrates

The acute toxicity of C8-18 and C18 unsatd. AAPB to Daphnia magna was investigated in a study conducted according to OECD TG 202 / part I (1984) under static conditions. Daphnia magna was exposed to 6 nominal concentrations ranging from 0.5 to 16 mg product/L. A 48 h LC50 of ca. 1.9 mg a.i/L (nominal) was determined based on an active matter content of 30%.

 

The 48 hr-acute toxicity of C8-18 AAPB (30% active matter) to Daphnia magna was investigated in a study conducted according to OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test) and EU Method C.2 (Acute Toxicity for Daphnia) under static conditions. Daphnids were exposed to control and test chemical at nominal concentrations of 6.25; 12.5; 25; 50; 100 mg product/L for 48 hr. The test material concentrations were analysed via UV absorption at 485 nm. The C8-18 AAPB concentrations were >80% (exception: 72.2% at the start in the 6.25 mg product/L group). The 48 h EC50 was determined to be 6.5 mg a.i./L based on nominal concentrations.

 

The acute toxicity of Formamidopropylbetaine to Daphnia magna was investigated in a study conducted according to OECD Guideline 202. The substance did not induce acute immobilisation of Daphnia magna at 100 mg/L after 48 hours of exposure. The 48h-EC50 was > 100 mg/L based on analytically confirmed nominal exposure concentrations.

 

Long-term toxicity to aquatic invertebrates

Several long-term toxicity studies in Daphnia magna are available for the source substances C8-18 AAPB and C8-18 and C18 unsatd. AAPB, which were included in the weight-of-evidence approach.

Three of the Daphnia magna  reproduction tests were conducted in reconstituted dilution water resulting in 21 d NOEC values of 0.03, 0.32, and 0.932 mg a.i./L. Based on the test results using 2/3 reconstituted dilution water and 1/3 pond water (21 d NOEC=0.9 mg a.i./L), it can be assumed that the presence of pond water has little or no influence, as the results are comparable to those obtained in the newly performed study in which analytical monitoring of the test substance concentration was performed using state-of-the-art equipments and techniques and which seems to be the most reliable study.

The very low 21 d NOEC and LOEC of 0.03 and 0.1 mg a.i./L determined in one test could not be confirmed by the other studies and based on the available data this discrepancy could not be resolved. Therefore a weight of evidence approach seems to be justified taking into account the 21 d NOEC values of 0.03, 0.32, 0.9, and 0.932 mg a.i./L. The calculation yielded a 21 d NOEC of 0.3 mg a. i./L as the geometric mean with respect to reproduction.

 

Toxicity to aquatic algae and cyanobacteria

In a weight of evidence approach the acute aquatic toxicity to algae was found to be in the range of >1 to ≤ 10 mg/L. For practical reasons (to name a value for the algae effect concentration) the algae study with the lowest effect result within this range is used for the assessment of algae toxicity: 72 h ErC50 = 1.5 mg a.i./L, 72 h NOEC = 0.3 mg a.i./L.

 

Toxicity to microorganisms

The toxicity of C8-10 Alkylamidopropyl betaine (35% a.i.) to microorganisms was investigated during a ready biodegradation study (CO2 Evolution Test) according to OECD guideline 301 B (1992) over a period of 28 days and using an inoculum obtained from activated sludge from a predominantly domestic sewage treatment plant.

Inoculum blank, procedural/functional control with the reference substance Sodium acetate and a toxicity control with 45 mg/L test item and 35 mg/L reference item Sodium acetate were performed.

The reference item degraded normally (68% within 14 days). By the end of the test, the reference item was degraded by 82%.

The biodegradation of the item mixture in the toxicity control was found to be 63% after 14 days of incubation. Thus, according to the test guidelines, the test item had no inhibitory effect on activated sludge microorganisms at the tested concentration of 45 mg/L, as the biodegradation in the toxicity control was higher than 35% within 14 days of incubation.

Justification for read-across

For details on substance identity and detailed toxicological profiles, please refer also to the general justification for read-across given at the beginning of the CSR and attached as pdf document to IUCLID section 13.

This read-across approach is justified based on structural similarities. The target and source substances contain the same functional groups. Thus a common mode of action can be assumed.

The only deviation within this group of substances is a variety in their carbon chain length, which did not have a relevant impact on ecotoxicity as demonstrated by the available data on the target and source substances.

 

a. Structural similarity and functional groups

The target substance C8-10 Alkylamidopropyl betaine is a UVCB substance manufactured from fatty acids (C8 and C10) and N, N-dimethylpropylenediamine (DMAPA) and further reacted with sodium monochloroacetate.

The source substances C8-18 AAPB and C8-18 and C18 unsatd. AAPB are UVCB substances manufactured from natural fatty acids or oils with N, N-dimethylpropylenediamine (DMAPA) and further reacted with sodium monochloroacetate. As their origin is from natural sources, the used fatty acids may have a mixed slightly varying composition with an even numbered chain length from C8 to C18. Unsaturated C18 amounts may be included.

The source substance Formamidopropylbetaine is a monoconstituent substance manufactured from formic acid and  N, N-dimethylpropylenediamine (DMAPA) and further reacted with sodium monochloroacetate.

 

b. Differences

Differences in chemical and other intrinsic properties of the target and source substances could potentially arise from the following facts:

-Different amounts of different carbon chain lengths (carbon chain length distribution):

Higher amounts of higher chain lengths and corresponding lower amounts of lower chain length lead to a rising average lipophilicity as can be seen from the increasing log Kow from Formamidopropylbetaine (log Kow: -3.3), C8-10 Alkylamidopropyl betaine (log Kow: 2.2), C12 AAPB (log Kow: 3.54), C8-18 AAPB (log Kow: 4.23).

However, based on the available ecotoxicological data it is demonstrated, that this read-across approach is nevertheless reliable.

 

- Different amounts of unsaturated fatty ester moieties:

The source substance C8-18 and C18 unsatd. AAPB contains considerable amounts of unsaturated C18 chains, which represents a worst case with respect tosome toxicological endpoints, mainly local effects (e.g. irritation, sensitisation) and reactivity.

 

The provided structural similarities and impurity profiles support the proposed read-across hypothesis with high confidence.

 

Comparison of ecotoxicity data

 

Endpoints	Target substance	Source substances		Source substance
	C8-10 Alkylamidopropyl betaine	C8-18 and C18 unsatd. AAPB	C8-18 AAPB	Formamidopropylbetaine
Short-term toxicity to fish	key_Short-term toxicity to fish: 73772-45-9 / 73772-46-0_9.1.3._Evonik_2015_OECD 203   OECD Guideline 203 (Fish, Acute Toxicity Test) Danio rerio, semi-static, freshwater, natural river water containing 3.46 mg/L TOC (2.71 mg/L DOC)   96 h LC50 > 100 mg/L,act. ingr. (nominal) based on: mortality   Reliability: 1 (reliable without restrictions), GLP	Sup_RA_Short-term toxicity to fish.61789-40-0_9.1.3_Acute_fish_Unilever_AT-R728-01 OECD Guideline 203 (Fish, Acute Toxicity Test) Pimephales promelas, semi-static, freshwater 96 h NOEC = 0.54 mg/L,act. ingr. (nominal)  96 h LC100 = 1.68 mg/L,act. ingr. (nominal)  96 h LC50 = 1.11 mg/L,act. ingr. (nominal) based on: mortality (95% c.i.: 0.54-1.68 mg a.i./L)   Reliability: 1 (reliable without restrictions), no data on GLP	Sup_RA_(prolonged fish test: 28 d).Short-term toxicity to fish.97862-59-4_9.1.3_IUA_1995_OECD_204 OECD Guideline 204 (Fish, Prolonged Toxicity Test: 14-day Study)   Oncorhynchus mykiss, flow-through, freshwater   28 d NOEC = ca. 0.16 mg/L act. ingr. (nominal) based on: mortality   28 d LOEC = ca. 0.5 mg/L act. ingr. (nominal) based on: mortality   No deaths < 1.6 mg/L; 10/10 fish died within 4 d at >/= 1.6 mg/L   Reliability: 1 (reliable without restrictions), GLP	sup_RA_NOTOX 454073 Short-term toxicity to fish   OECD Guideline 203 (Fish, Acute Toxicity Test) Cyprinus carpio, static, freshwater   96 h LC50 > 100 mg/L,act. ingr. (meas., arithm. mean) based on: mortality   Reliability: 1 (reliable without restrictions), GLP
Long-term toxicity to fish	No data, read-across	No data	WoE_RA_Long-term toxicity to fish: 97862-59-4_9.1.6.1_THG_2008_OECD 210   OECD Guideline 210 (Fish, Early-Life Stage Toxicity Test)   Oncorhynchus mykiss, flow-through, freshwater   37 d NOEC = 0.135 mg/L act. ingr. (nominal) based on: egg hatch   37 d LOEC = 0.405 mg/L act. ingr. (nominal) based on: egg hatch   100 d NOEC = 0.135 mg/L act. ingr. (nominal) based on: length, dry weight, morphological and behavioural effects, post hatch success, overall survival   100 d LOEC = 0.405 mg/L act. ingr. (nominal) based on: length, dry weight, morphological and behavioural effects, post hatch success, overall survival   Reliability: 1 (reliable without restrictions), GLP	No data
			Woe_RA_(prolonged fish test: 28 d).Short-term toxicity to fish.97862-59-4_9.1.3_IUA_1995_OECD_204 OECD Guideline 204 (Fish, Prolonged Toxicity Test: 14-day Study)   Oncorhynchus mykiss, flow-through, freshwater   28 d NOEC = ca. 0.16 mg/L act. ingr. (nominal) based on: mortality   28 d LOEC = ca. 0.5 mg/L act. ingr. (nominal) based on: mortality   No deaths < 1.6 mg/L; 10/10 fish died within 4 d at >/= 1.6 mg/L   Reliability: 1 (reliable without restrictions), GLP
Short-term toxicity to aquatic invertebrates	No data, read-across	WoE_RA_Short-term toxicity to aquatic invertebrates: 61789-40-0_9.1.1_KAO Corporation_1992_OECD 202   OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test) (part I, 24h EC50 Acute Immobilization Test (1984)) Daphnia magna, static, freshwater   48 h EC50 ca. 1.9 mg/Lact. ingr. (nominal) based on: mobility (95% CL: 1.37 - 2.69 mg a.i./L)   Reliability: 2 (reliable with restrictions), GLP	WoE_RA_Short-term toxicity to aquatic invertebrates: 97862-59-4_9.1.1_THG_1991c_OECD 202   OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test) Daphnia magna, static, freshwater   48 h EC50 = 6.5 mg/Lact. ingr. (nominal) based on: mobility (95% C.I.: 4.8 - 8.4 mg a.i./L) 24 h EC50 > 30 mg/Lact. ingr. (nominal) based on: mobility   Reliability: 1 (reliable without restrictions), GLP	WoE_RA_NOTOX 454084 Short-term toxicity to aquatic invertebrates   OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test) Daphnia magna, static, freshwater   48 h EC50 >100 mg/Lact. ingr. (meas., arithm. mean) based on: mobility Reliability: 1 (reliable without restrictions), GLP
Long-term toxicity to aquatic invertebrates	No data, read-across	WoE_RA_Long-term toxicity to aquatic invertebrates: 61789-40-0_9.1.5_Unilever Research_1990   OECD Guideline 211 (Daphnia magna Reproduction Test) (cited as OECD Guideline 202, part 2 (Daphnia sp., Reproduction Test)) Daphnia magna, semi-static, freshwater   21 d NOEC = 0.32 mg/Lact. ingr. (nominal) based on: reproduction 21 d LOEC = 0.56 mg/Lact. ingr. (nominal) based on: reproduction 21 d NOEC = 0.56 mg/Lact. ingr. (nominal) based on: mortality 21 d LOEC = 1 mg/Lact. ingr. (nominal) based on: mortality   Reliability: 2 (reliable with restrictions), GLP	WoE_RA_Long-term toxicity to aquatic invertebrates: 97862-59-4_9.1.5_IUA_1995_OECD 202   OECD Guideline 211 (Daphnia magna Reproduction Test) (cited as OECD Guideline 202, part 2 (Daphnia sp., Reproduction Test)) Daphnia magna, semi-static, freshwater 21 d NOEC = 0.032 mg/Lact. ingr. (nominal) based on: survival and reproduction rate 21 d LOEC = 0.1 mg/Lact. ingr. (nominal) based on: survival and reproduction rate   Reliability: 1 (reliable without restrictions), GLP	WoE_RA_Long-term toxicity to aquatic invertebrates: 120128-90-7_9.1.5_OECD 211_Evonik_2011   OECD Guideline 211 (Daphnia magna Reproduction Test) Daphnia magna, semi-static, freshwater   21 d NOEC >37 mg a.i/L mg/Lact. ingr. (nominal) based on: reproduction, growth   Reliability: 1 (reliable without restrictions), GLP
			WoE_RA_Long-term toxicity to aquatic invertebrates: 97862-59-4_9.1.5_THG_1991d_OECD 202   OECD Guideline 211 (Daphnia magna Reproduction Test) (cited as OECD Guideline 202, part 2 (Daphnia sp., Reproduction Test)) Daphnia magna, semi-static, freshwater 21 d NOEC = 0.9 mg/Lact. ingr. (nominal) based on: reproduction 21 d LOEC = 3.6 mg/Lact. ingr. (nominal) based on: reproduction   Reliability: 1 (reliable without restrictions), GLP
			WoE_RA_Long-term toxicity to aquatic invertebrates: 97862-59-4_9.1.5_CEFIC_CESIO_2006a_OECD 211   OECD Guideline 211 (Daphnia magna Reproduction Test) Daphnia magna, semi-static, freshwater   21 d NOEC = 0.932 mg/Lact. ingr. (nominal) based on: reproduction 21 d LOEC = 2.98 mg/Lact. ingr. (nominal) based on: reproduction   Reliability: 1 (reliable without restrictions), GLP
Toxicity to aquatic algae and cyanobacteria	No data, read-across	WoE_RA_Toxicity to aquatic algae and cyanobacteria: 61789-40-0_9.1.2_Henkel_1992_DIN 38412 part 9   DIN 38412, part 9: Bestimmung der Hemmwirkung von Wasserinhaltsstoffen auf Grünalgen, Desmodesmus subspicatus (reported as Scenedesmus subspicatus), freshwater, static   72 h EC50 = ca. 1.5 mg/L,act. ingr. (nominal) based on: growth rate Reliability: 2 (reliable with restrictions), GLP	WoE_RA_Toxicity to aquatic algae and cyanobacteria: 97862-59-4_9.1.2_THG_1993e_OECD 201 OECD Guideline 201 (Alga, Growth Inhibition Test),Scenedesmus subspicatus (new name: Desmodesmus subspicatus), freshwater, static 72 h EC50 = ca. 14.7 mg/L,act. ingr. (nominal) based on: growth rate   Reliability: 2 (reliable with restrictions), GLP	WoE_RA_NOTOX 454095 Toxicity to aquatic algae and cyanobacteria   OECD Guideline 201 (Alga, Growth Inhibition Test),Selenastrum capricornutum (new name: Pseudokirchnerella subcapitata), freshwater, static   72 h EC50 >100 mg a.i./L (meas., arithm. mean)based on: growth rate   72 h NOEC =100 mg a.i./L (meas., arithm. mean)based on: growth rate   Reliability: 1 (reliable without restrictions), GLP
		WoE_RA_Toxicity to aquatic algae and cyanobacteria: 61789-40-0_9.1.2_CEFIC_CESIO_2006b_OECD 201 OECD Guideline 201 (Alga, Growth Inhibition Test),Desmodesmus subspicatus, freshwater, static   72 h NOEC = 3.86 mg/Lact. ingr. (nominal) based on: growth rate 72 h EC50 = 9.86 mg/Lact. ingr. (nominal) based on: growth rate (95% c.i. 9.33 - 10.4 mg/L) 72 h LOEC = 7.73 mg/Lact. ingr. (nominal) based on: growth rate Reliability: 1 (reliable without restrictions), GLP
		WoE_RA_Toxicity to aquatic algae and cyanobacteria.61789-40-0_9.1.2_Acute-algae_Unilever_A19_AL-L17-01 OECD Guideline 201 (Alga, Growth Inhibition Test),Desmodesmus subspicatus (reported as Scenedesmus subspicatus), freshwater, static   72 h NOEC = 1.8 mg/Lact. ingr. (nominal) based on: biomass and growth rate 72 h EC50 = 5.6 mg/Lact. ingr. (nominal) based on: growth rate   Reliability: 2 (reliable with restrictions), no GLP
		WoE_RA_Toxicity to aquatic algae and cyanobacteria.61789-40-0_9.1.2_Acute-algae_Unilever_A18_AL-L474-01 OECD Guideline 201 (Alga, Growth Inhibition Test),Selenastrum capricornutum (new name: Pseudokirchnerella subcapitata), freshwater, static   96 h NOEC = 3.2 mg/Lact. ingr. (nominal) based on: biomass and growth rate 96 h EC50 > 10 mg/Lact. ingr. (nominal) based on: growth rate   Reliability: 2 (reliable with restrictions), no GLP
		WoE_RA_Toxicity to aquatic algae and cyanobacteria: 61789-40-0_9.1.2_Hüls_1996_EEC 92-69 C3 EU Method C.3 (Algal Inhibition test) (cited as Directive 92/69/EEC, C.3,Desmodesmus subspicatus (reported as Scenedesmus subspicatus), freshwater, static   72 h EC50 > 334 mg/Lact. ingr. (nominal) based on: growth rate 72 h EC10 = 37.2 mg/Lact. ingr. (nominal) based on: growth rate Reliability: 2 (reliable with restrictions), GLP

 

A short-term toxicity study with fish (Danio rerio) is available for the target substance C8-10 Alkylamidopropyl betaine. The 96 h LC50 was >100 mg/L (nominal).

For the source substances several short-term toxicity studies to fish according to OECD Guideline 203 are available: C8-18 AAPB (Danio rerio), C8-18 and C18 unsatd. AAPB (Pimephales promelas, Danio rerio, Cyprinus carpio), Formamidopropylbetaine (Cyprinus carpio). Furthermore a prolonged fish toxicity test to Oncorhynchus mykiss with C8-18 AAPB conducted according to OECD Guideline 204 is available. The lowest 96 h LC50 was determined to be 1.11 mg a.i./L (nominal) in Pimephales promelas. The 96 h LC50 of Formamidopropylbetaine was >100 mg/L (measured, arithm. mean).

The LC50 values obtained with the source substances C8-18 AAPB and C8-18 and C18 unsatd. AAPB in fish were lower than for the target substance. Fish was the most sensitive trophic level. Thus, the results from the studies with aquatic invertebrates and algae obtained with the source substances C8-18 AAPB and C8-18 and C18 unsatd. AAPB are considered to be also protective for these trophic levels.

A long-term toxicity study to freshwater fish (Oncorhynchus mykiss) according to OECD Guideline 210 (Early-Life Stage Toxicity Test) conducted with the source substance C8 -18 AAPB is available. The 100 day overall NOEC was 0.135 mg a.i./L.

Short-term toxicity studies to freshwater invertebrates are available for C8-18 and C18 unsatd. AAPB, C8-18 AAPB and Formamidopropylbetaine (Daphnia magna; according to OECD Guideline 202). The lowest 48 h EC50, determined to be ca. 1.9 mg a. i./L (nominal) was used for further assessment. 

Long-term toxicity studies to aquatic invertebrates (Daphnia magna) according to OECD Guideline 211 are available for C8-18 AAPB, C8-18 and C18 unsatd. AAPB and Formamidopropylbetaine. In a weight of evidence approach the 21 d NOEC was determined to be 0.3 mg a.i./L (geometric mean) with respect to reproduction.

Toxicity studies to aquatic algae and cyanobacteria (Desmodesmus subspicatus; Pseudokirchnerella subcapitata) according to OECD Guideline 201 or DIN 38412, part 9 are available for C8-18 AAPB, C8-18 and C18 unsatd. AAPB and Formamidopropylbetaine. EC50 values were in the range of >1 to ≤ 10 mg/L (> 100 mg/L for Formamidopropylbetaine). In a weight of evidence approach, considering all available information for toxicity to aquatic algae, the lowest effect result within this range is used for the assessment of algae toxicity: 72h-ErC50 = 1.5 mg a.i./L, 72h-NOEC = 0.3 mg a.i./L.

 

Quality of the experimental data of the analogues:

The available data are adequate and sufficiently reliable to justify the read-across approach.

The key studies were conducted according to OECD TG 203, 204, 210, 202, 211 and 201/DIN 38412 part 9/ EU Method C.3 and were reliable (RL1) or reliable with restrictions (RL2).

The test materials used in the respective studies represent the source substance as described in the hypothesis in terms of substance identity and minor constituents.

Overall, the study results are adequate for the purpose of classification and labelling and risk assessment.

 

Conclusion

As fatty acids independently from their chain length and degree on unsaturation are generally considered to be not toxic, a variability in the fatty acid moiety is not expected to have any influence on the ecotoxic potential of the substances.

The most sensitive organisms was found to be fish (fish early life stage test: 100 d NOEC=0.135 mg a.i./L).

The LC50 values obtained with the source substances C8-18 AAPB and C8-18 and C18 unsatd. AAPB in fish were lower than for the target substance. Thus, the results from the studies with aquatic invertebrates and algae obtained with the source substances C8-18 AAPB and C8-18 and C18 unsatd. AAPB are considered to be also protective for these trophic levels.

 

This result was considered as an appropriate starting point for deriving PNECs for the aquatic compartment (including sediment).