Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

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Additional information

Statement on non-classification for acute aquatic toxicity

Overall conclusion

Taking into account all acute aquatic toxicity data (fish, daphnia and algae) it is the registrants expert judgement that C8-18 AAPB is toxic to aquatic organism, corresponding to Acute Cat. 2 according to the Global Harmonized System (GHS/UN). As this building block is not implemented in Europe, it is not appropriate to classify C8-18 AAPB for acute aquatic effects.

 

Data situation algae acute

There are 8 valid acute algae studies available, 7 fresh water algae studies with Desmodesmus subspicatus and Pseudokirchnerella subcapitata (72h-ErC50 1.5 - > 334 mg a.i./L) and one marine algae study with Skeletonema costatum (72 h ErC50 = 0.97 mg a.i./L).

The test result with Skeletonema costatum (72 h ErC50 = 0.97 mg a.i./L) is the only acute aquatic test result with an EC50 below 1 mg a.i./L.

 

Justification for non-classification aquatic acute 1

The registrant carefully examined and reassessed the whole data situation for the aquatic environment. The fact that there are 8 acute algae studies with 3 different algae species with EC50 effect concentrations within the range 0.97 - > 334 mg a.i./L, justifies the application of a weight of evidence approach (WoE) considering all this data for classification instead of considering only the study with the lowest effect concentration. Expert judgement is, that the ecotox profile of C8-18 AAPB is characterised by an acute aquatic toxicity in the range of >1 to ≤ 10 mg/L. As a consequence C8-18 AAPB is classified as toxic rather than very toxic to aquatic organism Therefore no classification for acute aquatic toxicity Category 1 is necessary.

 

Justification for using a WoE approach considering all algae studies, not only the study with the lowest effect concentration (0.97 mg a.i./L) for classification

 

For C8-18 AAPB the following aquatic ecotoxicity test results are available:

·     acute data with daphnia, fish, algae for fresh water as well as salt water species.

·     chronic data with algae for fresh water and marine species

·     chronic data with fish and daphnia for fresh water species

 

The overall available acute test data for fish and invertebrates, fresh water as well as salt water species, do not allow classification aquatic acute for C8-18 AAPB.

For algae there are 7 acute tests with Desmodesmus subspicatus and Pseudokirchnerella subcapitata (72 h ErC50 1.5 - > 334 mg a.i./L) and one marine algae study with Skeletonema costatum (72 h-ErC50 = 0.97 mg a.i./L). For the examination of environmental acute classification a weighted treatment of the overall dataset is used (weight of evidence approach). The overall dataset for aquatic acute tests (table 1) suggests, that Skeletonema costatum should not be seen as the most sensitive species (argumentation below table 1). Nevertheless, EC50 of 0.97 mg/L for Skeletonema costatum is the only aquatic acute test value below the threshold for classification – considering that this number is quite close to the threshold limit (1.0 mg/L).

Having in mind acute data for invertebrates and fish, the obvious fact of marine algae not being the most sensitive species and the very small difference of EC50 of Skeletonema costatum 0.97 mg/L to the classification limit (1 mg/L), it is misleading to classify C8-18 AAPB based on this test result, as a single value of 0.97 mg a.i./L is not representative for the ecotoxicity profile of this substance. As a consequence data are sufficient for not classifying C8-18 AAPB as aquatic Acute Cat. 1.

 

 

Table1   Comparison of sensitivity of freshwater and marine species (lowest test result resp. test result used for hazard assessment)

 

 

fish

 

daphnia

 

algae

 

acute

 

EC50[mg a.i. / L]

 

-      freshwater

 

1.11

 

1.9

 

1.5

 

-      marine water

 

>> 1.1

 

7

 

0.97

 

chronic

 

NOEC [mg a.i. / L]

 

-      freshwater

 

0.135

 

0.3

 

0.3

 

-      marine water

 

-

-

0.47

 

 

Consideration of species sensitivity and marine /freshwater sensitivity

·     From the comparison of available chronic tests, test results suggest the species fish being the most sensitive species, not daphnia or algae. The test result for fish (NOEC, fresh water) is by a factor of 2.2 lower than test results for daphnia or algae (NOEC, fresh water) and furthermore by a factor of 2.7 lower than the test result for the marine algae (NOEC).

·     The comparison of marine and freshwater acute test results for fish and daphnia shows that in each case the freshwater species is more sensitive than the marine species. The comparison of marine and freshwater chronic algae test results show also the freshwater algae being slightly lower than the marine algae.

 

There is only one single test result, that doesn’t match the observations described above: the acute marine test with Skeletonema costatum resulting in an EC50 of 0.97 mg/L. As a consequence this test result is considered as being of inferior relevance for classification purposes compared to the other algae tests.

 

An additional argument is the fact that the range finding test for the study with Skeletonema costatum resulted in a 72 h-EC50 of 2.61 mg/l a.i. This number is substantially higher than the definitive test result and also quite above the classification limit.

 

Aquatic toxicity:

Alkylamidopropyl betaines are typical UVCB substances. 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. Lauramidopropyl betaine is the major ingredient of all AAPBs.

All AAPBs are similar in structure and contain all the same zwitterionic structure. They differ, however, by their carbon chain length distribution and the degree of unsaturation (≤ 20%) in the fatty acid moiety. The content of minor constituents in all products are comparable and differ only slightly. Based on the similar chemical structure a common mode of action of all AAPBs is to be expected and it can be assumed that chain length distribution and degree of unsaturation of the fatty acid chain have no or at the most a minor impact on this endpoints.

 

Freshwater fish

In a semi-static test conducted according to OECD Guideline 203 and EU Method C.1 using Pimephales promelas as test organism a 96 h LC50=1.11 mg a. i./L (nominal; no analytical monitoring of test substance concentration; pH not adjusted; pH range: 7.2 -7.6) was determined. In two semistatic test conducted according to OECD Guideline 203 and/or EC Method C.1 with Danio rerio (pH adjusted) and Cyprinus carpio (pH not adjusted; pH range: 7.8 -8.2) 96 h LC50values of ca. 2 mg a. i./L nominal were derived. Analytical monitoring of test substance concentrations were not conducted in the test with Danio rerio. In the semi-static test with Cyprinus carpio the concentration of Coco AAPB was stable during the incubation time which has been shown by analytical monitoring via TOC (non-specific method).

 

The acute toxicity of C8-18 AAPB towards fish (Danio rerio) was investigated in a study conducted according to OECD Guideline 203 (Fish, Acute Toxicity Test) and ISO 7346-1 (Determination of the Acute Lethal Toxicity of Substances to a Freshwater Fish [Brachydanio rerio Hamilton-Buchanan (Teleostei, Cyprinidae) ] - Part 1: Static Method). The 96 h LC50was found to be 15 mg/L nominal (no information whether this value refers to test material or active matter).

Furthermore the results of a prolonged fish toxicity test are available. In this 28-d toxicity study conducted according to OECD Guideline 204, rainbow trouts (Oncorhynchus mykiss) were exposed to C8-18 AAPB under flow-through conditions. The 28-d NOEC and LOEC values were 0.16 and 0.5 mg a. i./L nominal based on mortality and sub-lethal effects.

 

Saltwater fish

The acute toxicity of Coco AAPB to the marine fish Cyprinodon variegatus was investigated in a study conducted according to OECD Guideline 203 (Fish, Acute Toxicity Test) adapted by OSPARCOM (2005 -11) for marine testing of offshore chemicals. In this limit test conducted under semi-static conditions, the fish were exposed to a single concentration of 3 mg product/L nominal (corresponding to 1.1 mg a. i./L) for 96 h. No effects were observed at 1.1 mg a. i./L nominal.

 

Conclusion

For freshwater fish (Pimephales promelas) the lowest 96 h LC50was determined to 1.11 mg a. i./L nominal, and for marine fish (Cyprinodon variegatus) to 1.1 mg a. i./L nominal.

The obtained results were considered to be valid for the AAPBs.

 

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. 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 behavioral effects, post hatch success and overall survival.

Additional data are available from a prolonged 28-d toxicity study conducted according to OECD Guideline 215 Draft 'Juvenile growth test: 28 d' (1992) (see table Overview of short-term effects on fish). Rainbow trouts (Oncorhynchus mykiss) were exposed to C8-18 AAPB under flow through conditions. A 28-d NOEC=0.16 mg a. i./L nominal was determined based on growth (body length and mean body wet weight). At higher test concentrations of 0.5 and 1.6 mg a. i./L nominal, the growth rates could not be determined, since all fish died during the test period.

 

Conclusion:

The obtained NOECs of 0.135 and 0.16 mg a. i./L of C8 -18 AAPB were in the same range. The obtained results were considered to be valid for the AAPBs.

The NOEC of 0.135 mg a. i./L obtained from the long-term study including early life-stage was selected for further assessment and derivation of PNEC.

 

Short-term toxicity to aquatic invertebrates

Reliable results on the acute toxicity of Coco AAPB and C8-18 AAPB to fresh water and of Coco AAPB to salt water invertebrates obtained in guideline studies are available. The obtained results were considered to be valid for the AAPBs.

 

Freshwater invertebrates

After an exposure period of 48 h, EC50values of 1.9, 4.1 and 6.6 mg a. i./L nominal were determined for Coco AAPB and 6.5 mg a.i./L nominal for C8-18 AAPB, respectively. Studies were conducted according to OECD 202 and/or EU Method C.2. Two static tests were conducted with analytical monitoring of test substance concentration and one test was performed under semi-static conditions. The stability of the test compound during the exposure period could be shown by analytical monitoring (photometer and TOC analysis, respectively). The effective concentrations were > 80 % of the nominal concentration with one exception: in the study conducted with C8-18 AAPB, only 72 % of initial nominal concentration was detected at day 0 at a concentration of 6.25 mg product/L. The pH was adjusted in two studies according to guideline. In the other studies, the pH was not adjusted or no information is available with respect to this. The pH values of these studies, however, were in the acceptable range (7.6 -8.4).

The lowest 48 h EC50, determined to be ca. 1.9 mg a. i./L nominal was used for further assessment.

 

Marine invertebrates

The acute toxicity of Coco AAPB to the marine copepod Acartia tonsa was investigated in a study conducted according to ISO 14669 (1999) Water Quality - Determination of the acute lethal toxicity to marine capepods (Copepoda; Crustacea). Acartia tonsa were exposed to nominal Coco AAPB static conditions for 48 h. The 48 h NOEC and LC50values were determined to be 3.6 mg a. i./L and 7.0 mg a. i./L nominal, respectively. The 48 h LC50 of 7.0 mg a. i./L nominal was used for further assessment.

 

 

Long-term toxicity to aquatic invertebrates

Long-term toxicity data are available for C8-18 AAPB and Coco AAPB. Three of the reproduction tests were conducted in reconstituted dilution water resulting in 21 d NOEC values of 0.03, 0.32, and 0.932. 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. As already mentioned above, 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. The obtained results were considered to be valid for the AAPBs.

In the first study the 21 d toxicity of C8-18 AAPB to Daphnia magna was investigated according to OECD Guideline 211 (Daphnia magna Reproduction Test) under semi-static conditions. The analytically determined concentrations of C8-18 AAPB in the freshly prepared test media of the analysed test concentrations of 0.32, 1.0, and 3.2 mg/L varied from 101 to 124 % of the nominal concentrations, the mean measured values of all measurements amounted from 104 to 118 % of the respective nominal value. In the test media samples taken out of the actual biological test (including algal food), the test substance concentration could not be quantified due to disturbance of the measurements by the algae. However, additional stability controls showed that C8-18 AAPB was sufficiently stable in the test media (but without algal food and Daphnia) during the longest test medium renewal periods of 72 h. The 21 d NOEC and LOEC based on survival and reproduction were determined to be 0.03 and 0.1 mg a. i./L nominal, respectively. These very low values could not be confirmed in the other studies. Based on the available data this discrepancy could not be resolved.

In the second study the 21 d toxicity of Coco AAPB to Daphnia magna was investigated according to OECD Guideline 211 (Daphnia magna Reproduction Test) under semi-static conditions. The 21 d NOEC and LOEC values were determined to be 0.32 and 0.56 mg a. i./L in respect to reproduction. The most sensitive endpoint was release of the first brood (21 d NOEC=0.18 mg a. i./L; 21 d LOEC=0.32 mg a. i./L nominal each).

In the third study the 21-day-chronic toxicity of C8-18 AAPB (30 % active matter) to Daphnia magna was investigated according to OECD Guideline 211 (Daphnia magna Reproduction Test) under semi-static conditions. The test was performed in a mixture of 2/3 reconstituted water and 1/3 pond water. Per concentration 20 daphnids (ten per beaker) were kept in bulk culture. After 7 d 10 daphnids with eggs in the brood pouch were separated and kept individually. The remaining daphnids were observed for mortality rates (unhealthy and damaged daphnids were excluded). At the start of the treatment periods the measured concentrations (photometric) ranged from 76.7 to 117 % of the nominal values and at the end of the exposure period from 76.3 to 96.9 %. Additionally performed stability controls showed that the test substance was sufficiently stable in the test media during the renewal periods. The 21-day NOEC and LOEC based on reproduction were 0.9 and 3.6 mg active substance/L nominal.

In the newly performed 21-day-chronic, semi-static reproduction tests conducted according to OECD Guideline 211 (Daphnia magna Reproduction Test) and EU Method C.20 (Daphnia magna Reproduction Test), the influence of natural ingredients in environmental aquatic systems on the chronic toxicity of C8-18 AAPB (28.4 % active matter) to Daphnia magna was investigated. Daphnids were exposed to control, and test chemical at nominal concentrations of 0.0284, 0.091, 0.290, 0.932 and 2.98 mg active substance/L (dilution water according to Elendt). Samples of all concentrations and control were analytically verified via LC-MS/MS on days 0, 2, 14 (fresh media, 0 h) and on days 2, 5, 16 (old media, 48/72 h). The recovery rates of fresh and old media of the biologically relevant concentration levels were > 80 %. The 21-day NOEC and LOEC based on reproduction were 0.932 and 2.98 mg active substance/L nominal, respectively (CEFIC/CESIO [ICCA Initiative] Alkylamidopropyl Betaines Consortium (2006a))

An additional study with same study design was conducted with natural river water. The study is described and compared to the study with reconstituted water as follows in the SIAR CAPB 2006.

“The test with natural river water resulted in a NOEC on reproduction of ≥ 2.98 mg active substance/l and a LOEC greater than 2.98 mg active substance/l (21 d-NOEC ≥ 10.5 mg product/l; 21 d-LOEC > 10.5 mg product/l). In these two studies additional parameters were investigated (e. g. first appearance of juveniles, intrinsic rate of natural increase). In the study with natural river water weak (but statistically significant) effects on the intrinsic rate were observed at all concentrations ≥ 0.32 mg product/L, showing no concentration effect relationship. Only at 10.5 mg/L a significant decrease in intrinsic rate and a significant effect on the first appearance of juveniles was determined. With reconstituted water the effect levels of reproduction rate, intrinsic rate, and first appearance were comparable. The test substance concentration was sufficiently stable at the relevant concentrations. Thus, humic acids and other natural ingredients have only a slight influence on the toxicity of C8-18 AAPB to Daphnia magna. The variation in the effect values described above could not be clarified.”

 

Conclusion:

As already mentioned above, 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

The toxicity of C8-18 AAPB, Coco AAPB and C12 AAPB to fresh water and salt water algae was investigated in 8 valid studies,7 fresh water algae studies with Desmodesmus subspicatus and Pseudokirchnerella subcapitata (72h-ErC501.5 - > 334 mg/l a.i.) and one marine algae study with Skeletonema costatum (72-h- ErC500.97 mg/l a.i.).

In a weight of evidence approach, considering all available information for the endpoint aquatic toxicity, the ecotox profile of C8-18 AAPB is characterised by an acute aquatic toxicity 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 acute 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.

 

Data included in the weight of evidence approach

 

1. In a test conducted according to DIN 38412, part 9 (comparable to OECD Guideline 201), the cultures of Desmodesmus subspicatus were exposed to Coco AAPB at nominal concentrations of 0.003, 0.009, 0.03, 0.09, 0.3, 0.9, 3.0 mg a.i./L under static conditions for 72 h. Originally, the data were evaluated according to the test guideline (DIN 38412, Part 9) using the EDV-program of Mr. Holtmann (Henkel KGaA). Based on today knowledge, this calculation model is no longer valid or only valid with restriction. Therefore, a recalculation of the 72 h EC50 values was performed taking into account the OECD principles. The 72 h ErC50, EbC50, and NOEC were found to be 1.5, 0.57, and 0.3 mg a.i./L nominal, respectively.

 

2. In a 72 hour toxicity study conducted according to OECD Guideline 201 (Alga, Growth Inhibition Test) and EU Method C.3 (Algal Inhibition test), the cultures of Desmodesmus subspicatus were exposed to Coco AAPB (30.9 % active matter) at nominal concentrations of 0.97, 1.93, 3.86, 7.72, 15.45, 30.9 mg active substance/L under static conditions. The 72 h NOEC, LOEC and EC50 values based on growth rate were 3.86, 7.73 and 9.86 mg a.i./L nominal, respectively. The 72 h NOEC, LOEC and EC50 values based on biomass were 1.93, 3.86 and 5.31 mg a.i./L nominal, respectively. There were no compound related phytotoxic effects. This toxicity study is regarded as reliable without restriction and satisfies the requirements of the guideline.

 

3. In a 72 hour acute toxicity study, the cultures of Desmodesmus subspicatus were exposed to C12 AAPB at nominal concentrations of 0.03, 0.096, 0.3, 0.96, 3, 9.6 mg a.i./L / under static conditions in accordance with the OECD Guideline 201 (2006).  The 72 h ErC50 value based on inhibition of specific growth rate was 3.15 mg a.i./L, the 72 h EyC50 value based on yield inhibition was 1.01 mg a.i./L, respectively. The 72 h NOEC based on growth rate and yield was determined to be 0.3 mg a.i./L nominal. No abnormalities were noted. The test item effects were observed to be reversible at the test concentrations 0.32 - 32 mg test mat. /L. (0.096 - 9.6 mg a.i./L). This toxicity study is classified as reliable without restriction and satisfies the requirements of the OECD Guideline 201 Alga, Growth inhibition test (2006).

 

4. In a 72 hour toxicity study conducted according to OECD Guideline 201 (Alga, Growth Inhibition Test), the cultures of Desmodesmus subspicatus were exposed to C8 -18 AAPB at nominal concentrations of 0, 0.098, 0.31, 0.98, 3.1, 9.8, and 31 mg active substance/L under static conditions. The 72 h ErC50 and 72 h EbC50 were 14.7 and 9.2 mg active substance/L nominal, respectively.  There were no compound related phytotoxic effects. This study is regarded as reliable with restrictions and satisfies the guideline requirements for a toxicity study with freshwater algae.

 

5. The toxicity of Coco AAPB to Scenedesmus subspicatus was investigated in a study conducted according to OECD Guideline 201 (Alga, Growth Inhibition Test), EU Method C.3 (Algal Inhibition test) and ISO 8692 (Water Quality - Fresh Water Algal Growth Inhibition Test with Scenedesmus subspicatus and Selenastrum capricornutum). Scenedesmus subspicatus was exposed to nominal concentrations of 0 (control), 1.0, 1.8, 3.2, 5.6, and 10.0 mg a.i./L for 72 h under static conditions. The 72 h EC50 and NOEC based on biomass and growth rate were determined to be 5.6 (growth rate) and 4.66 (biomass) and 1.8 mg a.i./L nominal (growth rate and biomass), respectively . This study is regarded as reliable with restrictions.

 

6. The toxicity of Coco AAPB to Selenastrum capricornutum was investigated in a study conducted according to OECD Guideline 201 (Alga, Growth Inhibition Test), EU Method C.3 (Algal Inhibition test) and ISO 8692 (Water Quality - Fresh Water Algal Growth Inhibition Test withScenedesmussubspicatus and Selenastrumcapricornutum). Selenastrum capricornutum was exposed to nominal concentrations of 0 (control), 0.56, 1.0, 1.8, 3.2, 5.6, and 10.0 mg a.i./L for 96 h under static conditions. The 96 h ErC50, EbC50 and NOEC were determined to be >10 (growth rate) and ca. 8 (biomass) and 3.2 mg a.i./L nominal (growth rate and biomass), respectively. This study is regarded as reliable with restrictions.

 

7. In a test conducted according to OECD Guideline 201, the cultures of Desmodesmus subspicatus were exposed to Coco AAPB at nominal concentrations of 0 (control), 4, 10, 25, 63, 158, and 395 mg dry residue/L for 72 h under static conditions. The stability of the test item was measured via TOC measurements. The recovery rate was >80%. After 72 h, the measured values differed from freshly prepared solutions by < 20%. The 72 h EC50 were determined to be 37.2 (biomass) and >334 mg a.i./L nominal (growth rate), respectively. This study is regarded as reliable with restrictions.

 

8. The toxicity of Coco AAPB to the marine phytoplankton Skeletonema costatum was investigated in a study conducted according to ISO 10253 (Water quality - Marine Algal Growth Inhibition Test with Skeletonemacostatum and Phaeodactylum tricornutum). Cultures of Skeletonema costatum in the exponential growth phase were exposed to nominal concentrations of 0.32, 1.0, 3.2, 5.6, and 10 mg product/L corresponding to 0.01, 0.36, 1, 2, and 3.6 mg a.i./L under static conditions for 72 h. The 72 h ErC50 and NOEC values were determined to be 2.05 mg product/L and 1 mg product/L (nominal each), respectively.

Effect concentrations based on a.i. as named in study report CoA (certificate of analysis) (= solids - sodium chloride) and recalculated for a.i. of registration substance composition (IUCLID chapter 1.2): 72 h ErC50: 0.97 mg a.i./L, 72 h NOEC: 0.47 mg a.i./L.

Effect concentrations based on a.i. as named in study report CoA (certificate of analysis) (= solids - sodium chloride): 72 h ErC50: 0.74 mg a.i./L, 72 h NOEC: 0.36 mg a.i./L.

This toxicity study is regarded as reliable without restriction.

 

Toxicity to microorganisms

The toxicity of Coco AAPB to Pseudomonas was investigated in several studies conducted according to national standard methods (DIN 38412, part 8 and part 27) and according to EN ISO 10712, respectively. The available data point on a low toxicity of Coco AAPB to Pseudomonas putida (30 min/16 h EC0=3000 mg a.i./L nominal).

 

Read-across

For details on substance identity and detailed (eco)toxicological profiles, please refer to the endpoint specific justifications for read-across in the respective IUCLID sections as well as the general justification for read-across given at the beginning of the CSR and attached as pdf document to IUCLID section 13.