Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

Aquatic toxictiy:

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 rerioHamilton-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 tableOverview 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 LC50of 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 and Coco AAPB to fresh water algae was investigated in several reliable studies conducted according to guideline. There is more than one set of data on algae with the same endpoint, duration, life stage and testing condition with the same reliability rating and there is no specific reason that could explain the difference in results. According to “R.10.2.2 Evaluation and interpretation of data” these data are harmonised by a geometric mean. This weight of evidence approach was followed though the test results are slightly more than a factor of 10 apart.

As Desmodesmus subspicatus as well as Skeletonema costatum belong to the Eucaryota and according to TGD the sensitivity of fresh water and marine organisms are in general comparable, the EC50and NOEC values were calculated based on aweight of evidence approach. For fresh water algae, data from two reliable studies with the lowest EC50and NOEC values were included in the weight of evidence approach. In addition it seems to be justified to include the values obtained from the study conducted with C12 AAPB, as it is the main component of Coco AAPB and differs only in chain length distribution. Therefore a common mode of action can be assumed. For marine water data from one study are available. The obtained results were considered to be valid for the AAPBs.

Data included in the weight of evidence approach

 

Fresh water algae

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 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 current knowledge, this calculation model is no longer valid or only valid with restriction. Therefore, a recalculation of the data 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.

In the second 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 (aqueous solution, 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 EC50values based on growth rate were 3.86, 7.73 and 9.86 mg a. i./L nominal, respectively. The 72 h NOEC, LOEC and EC50values based on biomass were 1.93, 3.86 and 5.31 mg a. i./L nominal, respectively.

C12 AAPB was investigated in a 72 hour acute toxicity study. The cultures of Desmodesmus subspicatus were exposed under static conditions in accordance with the OECD Guideline 201. The 72 h ErC50value based on inhibition of specific growth rate was 3.15 mg a. i./L, the 72 h EyC50value 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).

 

Marine algae

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 Skeletonema costatum and Phaeodactylum tricornutum). Cultures of Skeletonema costatum in the exponential growth phase were exposed to Coco AAPB under static conditions for 72 h. The 72 h ErC50and NOEC values were determined to be 0.74 mg a. i./L and 0.36 mg a. i./L (nominal each), respectively.

Supporting data

The results were supported by further fresh water guideline studies (OECD 201, EU Method C.3, ISO 8692). ForScenedesmus subspicatus (Desmodesmus subspicatus),the 72 h ErC50, EbC50and NOEC values were determined to be in the range between 5.6 and 14.7 (growth rate), 4.66 and 9.2 (biomass), and 1.8 –3.55 mg a. i./L nominal (NOEC growth rate and biomass), respectively.

For Pseudokirchneriella subcapitata (Selenastrum capricornutum) the 96 h ErC50, EbC50and NOEC values were determined in a study on Coco AAPB to be >10 (growth rate) and ca. 8 (biomass) and 3.2 mg a. i./L nominal (NOEC growth rate and biomass), respectively. Compound related phytotoxic effects were not detected.

AAPBs were subject to the ICCA OECD program. In additional studies the toxicity to aquatic algae was investigated, comparing two different products, reconstituted water and natural river water. The following conclusion is cited from SIAR CAPB (2006).

“The effect values using natural river water are only slightly higher than using reconstituted

water. The influence of ingredients in natural aquatic systems on the algae toxicity can be neglected. It could also be shown, that the use of different products did not have an influence on the algae toxicity of cocamidopropyl betaine.”

Conclusion:

As justified above this endpoint was evaluated using a weight of evidence approach. The geometric mean calculation results in a 72 h ErC50of 2.4 mg a. i./L and a NOEC of 0.6 mg a. i./L taking into account 72 h ErC50values of 1.5, 9.86, 3.15, and 0.74 mg a. i./L, NOEC values of 0.3, 3.86, 0.3, and 0.36 mg a. i./L respectively.

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).

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