Reaction products of benzenesulfonic acid, mono-C20-24 (even)-sec-alkyl derivs. para-, calcium salts

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to fish

Type of information:

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

Adequacy of study:

key study

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
In this justification, the read-across (bridging) concept is applied, based on the chemical structure of the potential analogues, their toxicokinetic behaviour and other available (eco-)toxicological data.

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
C20-24 calcium sulfonate and Benzenesulfonic acid, C14-24-branched and linear alkyl derivs., calcium salts (CAS 115733-09-0) are members of a category of chemicals described as alkaryl sulfonates, which was established as part of the U.S. Environmental Protection Agency High Production Volume (HPV) Challenge Program. The substances of this category have a common functional group - the salt of aryl sulfonic acid. Furthermore, they all have a divalent alkaline earth metal, one or more linear and/or branched alkyl groups of variable chain length and branching characteristics or extended heterocyclic carbon system from the sulfonated benzene ring. Finally, they have common precursors and/or the likelihood of common breakdown products via physical and biological processes, resulting in structurally similar chemicals, and similar physicochemical properties, environmental fate, ecotoxicity and mammalian toxicity.
Concerning short-term toxicity to fish, it is believed that both substance will be metabolised by the same mechanisms by microorganisms and by other classes of living organisms. Therefore they are expected to follow the same pattern. For the detailed procedure of the read-across principle and justifications, please refer to the analogue approach justification depicted below and the separate Read-Across Statement (Chemservice S.A., 2017).

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
Source chemical: Benzenesulfonic acid, C14-24-branched and linear alkyl derivs., calcium salts (CAS 115733-09-0, EC No none)
Target chemical: Reaction products of benzenesulfonic acid, mono-C20-24 (even)-sec-alkyl derivs. para-, calcium salts (C20-24 calcium sulfonate, CAS No none, EC No none)

3. ANALOGUE APPROACH JUSTIFICATION
C20-24 calcium sulfonate and Benzenesulfonic acid, C14-24-branched and linear alkyl derivs., calcium salts (CAS 115733-09-0) are UVCB substances that are produced using similar manufacturing process and raw materials and are manufactured in mineral oil. They are members of a category of chemicals described as alkaryl sulfonates, which was established as part of the U.S. Environmental Protection Agency High Production Volume (HPV) Challenge Program. These substances are similar in that they have a common functional group, the salt of aryl sulfonic acid. TOXMATCH and OECD Toolbox QSAR structure similarity assessments using Tanimoto distance fingerprint, Hellinger distance atom environment, Euclidian distance and Dice calculations indicate that these substances are very similar. Likewise, they have similar physicochemical properties, similar environmental fate characteristics, and similar ecotoxicity and mammalian toxicity profiles. For example, these substances can dissociate only in the presence of strong acids such as in the stomach but are not expected to dissociate under environmental conditions. For further details on this, please refer to the separate Read-Across Statement (Chemservice S.A., 2017). The similar toxicity profiles indicate that they have a similar MOA. C20-24 calcium sulfonate and Benzenesulfonic acid, C14-24-branched and linear alkyl derivs., calcium salts (CAS 115733-09-0) are not classified for environmental toxicity.
The similar findings (refer to data matrix outlined below and the separate Read-Across Statement) for both substances support the conclusion that similar molecules are expected to be formed from both substances, and in consequence, similar effects can be reasonably expected. Hence, the analogue may perfectly serve as a read-across substance for the C20-24 calcium sulfonate and vice versa. So, based on the WOE of these data, the available data on CAS 115733-09-0 can be used to cover the systemic endpoints currently lacking for C20-24 calcium sulfonate and read across is scientifically justified, making further testing obsolete.

4. DATA MATRIX
There is mainly data available on the toxicological properties of the analogues CAS 61789-86-4 / its overbased version CAS 68783-96-0 and for CAS 70024-69-0 / its overbased version CAS 70024-71-4. Data on Reaction products of benzenesulfonic acid, mono-C20-24 (even)-sec-alkyl derivs. para-, calcium salts covers merely the physico chemical properties. Hence, the identification and discussion of common properties of the analogues and the C20-24 calcium sulfonate will be mainly based on this physicochemical data.
The available data for the following physico-chemical properties, which are relevant for absorption into living organisms, are very similar. The substances are rather huge molecules and have a similar molecular weight range, which triggers already similarities in their absorption/adsorption and desorption behaviour. Furthermore, the physico-chemical properties like their partition coefficient, water solubility and vapour pressure are similar. Regarding the application of these substances, the substances are usually solved in an inert mineral oil to enable handling. The C20-24 calcium sulfonate and all analogous substances are hydrolytically stable in the natural environment, as they do not contain hydrolysable groups. In addition, at least CAS 70024-69-0 and CAS 61789-86-4 are not readily biodegradable, and the available data suggests this to apply also for C20-24 calcium sulfonate. Taking into account the vast amount of data available for partition coefficient data on various calcium sulfonates it can be concluded that they do not have a significant potential for bioaccumulation in aquatic and terrestrial organisms. However, they are expected to be adsorbed to a significant extent to the sediment and soil and to be thereby not bioavailable, which was confirmed by the results of short-term toxicity tests to fish, daphnia and algae for CAS 70024-71-4; CAS 115733-09-0 and CAS 61789-64-4, in which the lowest LL50 was already > 100 mg/L WAF.
For the following toxicological endpoints there is data available derived from CAS 70024-69-0/ CAS 70024-71-4, Analogue of CAS 70024-69-0, CAS 115733-09-0, CAS 61789-86-4/ CAS 68783-96-0 and CAS 75975-85-8: Acute toxicity, Skin irritation / corrosion, Eye irritation /corrosion, Skin sensitization, Repeated dose toxicity, Genetic toxicity in vitro and in vivo and Toxicity to reproduction (fertility / developmental toxicity). Furthermore a rather extensive data package is available concerning the human sensitization potential of numerous analogous substances. For the acute oral toxicity, the values for all read across substances are very high, all LD50 values being above 2000 mg/kg (reaching in older tests up to greater than 20,000 mg/kg) and the values for the substances can be considered as similar within normal biological variations. The substances are also not toxic via the inhalation or the dermal route of exposure. Regarding Skin/Eye Irritation, the available data on CAS 70024-69-0 and CAS 61789-86-4 shows both substances to be not irritating to the skin or the eyes. The skin sensitization data in animals and humans (for CAS 75975-85-8; CAS 61789-86-4 and EC 939-141-6) evaluated in a weight-of-evidence approach indicates that low TBN calcium sulfonates (TBN < 300) are skin sensitizers with a specific concentration limit (SCL) of 10% and that high TBN calcium sulfonates (TBN ≥ 300) are not skin sensitizers. Last but not least, the available genetic toxicity data for Analogue of CAS 70024-69-0, CAS 61789-86-4 and its overbased version CAS 68783-96-0 prove all of these substances to be not mutagenic. The NOAELs derived for the endpoints Repeated dose toxicity (Analogue of CAS 70024-69-0 and CAS 61789-86-4) and Toxicity to reproduction (fertility / developmental toxicity for CAS 115733-09-0)) have been also found to be in a similar range.
For further details please refer to the seperate Read-Across Statement (Chemservice S.A., 2017) and/or the robust study summaries of the respective studies in this IUCLID file.

Reason / purpose for cross-reference:

read-across source

Duration:

96 h

Dose descriptor:

NOELR

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

other: WAF loading rate

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

LL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

other: WAF loading rate

Basis for effect:

mortality (fish)

Details on results:

No mortalities and no sub-lethal effects were noted at 100 mg/L WAF loading rate.

Results with reference substance (positive control):

Not applicable.

Reported statistics and error estimates:

None reported.

Validity criteria fulfilled:

yes

Remarks:

Scientifically validity criteria were met.

Conclusions:

The report describes a valid guideline study with GLP compliance. The calcium sulfonate Read-Across substance (CAS 115733-09-0) was found to be not toxic for Oncorhynchus mykiss up to concentrations of 100 mg/L. These results can be used to fulfill the information requirements for the chemical substance Reaction products of benzenesulfonic acid, mono-C20-24 (even)-sec-alkyl derivs. para-, calcium salts, due to the high structural similarity of these substances. For the detailed procedure of the read-across principle and justifications, please refer to the separate Read-Across Statement (Chemservice S.A., 2017).

Executive summary:

In a 96-hour acute toxicity study, juvenile Rainbow trouts (Oncorhynchus mykiss) were exposed to benzenesulfonic acid, C14-24-branched and linear alkyl derivs., calcium salts (CAS 115733-09-0) at nominal concentrations of 0 (control group) and 100 mg/L WAF loading rate under semi-static conditions. Water Accommodated Fractions (WAFs) were prepared due to the low water solubility of the calcium sulfonate read across substance. Water temperature, pH and dissolved oxygen concentrations were recorded daily throughout the test. No mortalities and no sublethal effects were noted at the highest tested concentration, thus the LL50(96h) is reported to be > 100 mg/L WAF with a corresponding NOELR of 100 mg/L WAF.

These results can be used to fulfill the information requirements for the chemical substance Reaction products of benzenesulfonic acid, mono-C20-24 (even)-sec-alkyl derivs. para-, calcium salts, due to the high structural similarity of these substances. For the detailed procedure of the read-across principle and justifications, please refer to the separate Read-Across Statement (Chemservice S.A., 2017).

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

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

Adequacy of study:

key study

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
In this justification, the read-across (bridging) concept is applied, based on the chemical structure of the potential analogues, their toxicokinetic behaviour and other available (eco-)toxicological data.

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
C20-24 calcium sulfonate and Benzenesulfonic acid, mono-C16-24-alkyl derivs., calcium salts (CAS 70024-69-0) and its overbased version (CAS 70024-71-4) are members of a category of chemicals described as alkaryl sulfonates, which was established as part of the U.S. Environmental Protection Agency High Production Volume (HPV) Challenge Program. The substances of this category have a common functional group - the salt of aryl sulfonic acid. Furthermore, they all have a divalent alkaline earth metal, one or more linear and/or branched alkyl groups of variable chain length and branching characteristics or extended heterocyclic carbon system from the sulfonated benzene ring. Finally, they have common precursors and/or the likelihood of common breakdown products via physical and biological processes, resulting in structurally similar chemicals, and similar physicochemical properties, environmental fate, ecotoxicity and mammalian toxicity.
Concerning short-term toxicity to fish, it is believed that both substance will be metabolised by the same mechanisms by microorganisms and by other classes of living organisms. Therefore they are expected to follow the same pattern. For the detailed procedure of the read-across principle and justifications, please refer to the analogue approach justification depicted below and the separate Read-Across Statement (Chemservice S.A., 2017).

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
Source chemical: Benzenesulfonic acid, mono C20-24-alkyl derivs., calcium salts, overbased (CAS 70024-71-4, EC 615-049-9)
Target chemical: Reaction products of benzenesulfonic acid, mono-C20-24 (even)-sec-alkyl derivs. para-, calcium salts (C20-24 calcium sulfonate, CAS No none, EC No none)

3. ANALOGUE APPROACH JUSTIFICATION
C20-24 calcium sulfonate, Benzenesulfonic acid, mono-C16-24-alkyl derivs., calcium salts (CAS 70024-69-0) and its overbased version Benzenesulfonic acid, mono C20-24-alkyl derivs., calcium salts, overbased (CAS 70024-71-4) are UVCB substances that are produced using similar manufacturing process and raw materials and are manufactured in mineral oil. They are members of a category of chemicals described as alkaryl sulfonates, which was established as part of the U.S. Environmental Protection Agency High Production Volume (HPV) Challenge Program. These substances are similar in that they have a common functional group, the salt of aryl sulfonic acid. TOXMATCH and OECD Toolbox QSAR structure similarity assessments using Tanimoto distance fingerprint, Hellinger distance atom environment, Euclidian distance and Dice calculations indicate that these substances are very similar. Likewise, they have similar physicochemical properties, similar environmental fate characteristics, and similar ecotoxicity and mammalian toxicity profiles. For example, these substances can dissociate only in the presence of strong acids such as in the stomach but are not expected to dissociate under environmental conditions. For further details on this, please refer to the separate Read-Across Statement (Chemservice S.A., 2017). The similar toxicity profiles indicate that they have a similar MOA. C20-24 calcium sulfonate, Benzenesulfonic acid, mono-C16-24-alkyl derivs., calcium salts (CAS 70024-69-0) and its overbased version Benzenesulfonic acid, mono C20-24-alkyl derivs., calcium salts, overbased (CAS 70024-71-4) are not classified for environmental toxicity.
The similar findings (refer to data matrix outlined below and the separate Read-Across Statement) for all three substances support the conclusion that similar molecules are expected to be formed from all three substances, and in consequence, similar effects can be reasonably expected. Hence, the analogue may perfectly serve as a read-across substance for the C20-24 calcium sulfonate and vice versa. So, based on the WOE of these data, the available data on CAS 70024-69-0 and its overbased version CAS 70024-71-4 can be used to cover the systemic endpoints currently lacking for C20-24 calcium sulfonate and read across is scientifically justified, making further testing obsolete.

4. DATA MATRIX
There is mainly data available on the toxicological properties of the analogues CAS 61789-86-4 / its overbased version CAS 68783-96-0 and for CAS 70024-69-0 / its overbased version CAS 70024-71-4. Data on Reaction products of benzenesulfonic acid, mono-C20-24 (even)-sec-alkyl derivs. para-, calcium salts covers merely the physico chemical properties. Hence, the identification and discussion of common properties of the analogues and the C20-24 calcium sulfonate will be mainly based on this physicochemical data.
The available data for the following physico-chemical properties, which are relevant for absorption into living organisms, are very similar. The substances are rather huge molecules and have a similar molecular weight range, which triggers already similarities in their absorption/adsorption and desorption behaviour. Furthermore, the physico-chemical properties like their partition coefficient, water solubility and vapour pressure are similar. Regarding the application of these substances, the substances are usually solved in an inert mineral oil to enable handling. The C20-24 calcium sulfonate and all analogous substances are hydrolytically stable in the natural environment, as they do not contain hydrolysable groups. In addition, at least CAS 70024-69-0 and CAS 61789-86-4 are not readily biodegradable, and the available data suggests this to apply also for C20-24 calcium sulfonate. Taking into account the vast amount of data available for partition coefficient data on various calcium sulfonates it can be concluded that they do not have a significant potential for bioaccumulation in aquatic and terrestrial organisms. However, they are expected to be adsorbed to a significant extent to the sediment and soil and to be thereby not bioavailable, which was confirmed by the results of short-term toxicity tests to fish, daphnia and algae for CAS 70024-71-4; CAS 115733-09-0 and CAS 61789-64-4, in which the lowest LL50 was already > 100 mg/L WAF.
For the following toxicological endpoints there is data available derived from CAS 70024-69-0/ CAS 70024-71-4, Analogue of CAS 70024-69-0, CAS 115733-09-0, CAS 61789-86-4/ CAS 68783-96-0 and CAS 75975-85-8: Acute toxicity, Skin irritation / corrosion, Eye irritation /corrosion, Skin sensitization, Repeated dose toxicity, Genetic toxicity in vitro and in vivo and Toxicity to reproduction (fertility / developmental toxicity). Furthermore a rather extensive data package is available concerning the human sensitization potential of numerous analogous substances. For the acute oral toxicity, the values for all read across substances are very high, all LD50 values being above 2000 mg/kg (reaching in older tests up to greater than 20,000 mg/kg) and the values for the substances can be considered as similar within normal biological variations. The substances are also not toxic via the inhalation or the dermal route of exposure. Regarding Skin/Eye Irritation, the available data on CAS 70024-69-0 and CAS 61789-86-4 shows both substances to be not irritating to the skin or the eyes. The skin sensitization data in animals and humans (for CAS 75975-85-8; CAS 61789-86-4 and EC 939-141-6) evaluated in a weight-of-evidence approach indicates that low TBN calcium sulfonates (TBN < 300) are skin sensitizers with a specific concentration limit (SCL) of 10% and that high TBN calcium sulfonates (TBN ≥ 300) are not skin sensitizers. Last but not least, the available genetic toxicity data for Analogue of CAS 70024-69-0, CAS 61789-86-4 and its overbased version CAS 68783-96-0 prove all of these substances to be not mutagenic. The NOAELs derived for the endpoints Repeated dose toxicity (Analogue of CAS 70024-69-0 and CAS 61789-86-4) and Toxicity to reproduction (fertility / developmental toxicity for CAS 115733-09-0)) have been also found to be in a similar range.
For further details please refer to the seperate Read-Across Statement (Chemservice S.A., 2017) and/or the robust study summaries of the respective studies in this IUCLID file.

Reason / purpose for cross-reference:

read-across source

Duration:

96 h

Dose descriptor:

LL0

Effect conc.:

10 000 other: mg/L WAF

Nominal / measured:

nominal

Conc. based on:

other: WAF loading rate

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

LL50

Effect conc.:

> 10 000 other: mg/L WAF

Nominal / measured:

nominal

Conc. based on:

other: WAF loading rate

Basis for effect:

mortality (fish)

Details on results:

Control mortality did not exceed the test validity criterion (i.e. <10 % mortality in controls).
No mortality or signs of toxicity were noted in either the control or the 10,000 mg/L WAF treatment throughout the test.

Results with reference substance (positive control):

96 hour LC50 was 1.2 mg/L

Reported statistics and error estimates:

Statistical analysis of the data was not warranted on the basis that no mortality occurred in this study.

Validity criteria fulfilled:

yes

Remarks:

Scientifically validity criteria were met.

Conclusions:

The report describes a valid guideline study with GLP compliance. The calcium sulfonate Read-Across substance (CAS 70024-71-4) was found to be not toxic for Sheepshead minnow (Cyprinidon variegatus) at a loading of 10000 mg/L nominal WAF. These results can be used to fulfill the information requirements for the chemical substance Reaction products of benzenesulfonic acid, mono-C20-24 (even)-sec-alkyl derivs. para-, calcium salts, due to the high structural similarity of these substances. For the detailed procedure of the read-across principle and justifications, please refer to the separate Read-Across Statement (Chemservice S.A., 2017).

Executive summary:

Cyprinodon variegatus (Sheepshead minnow) was used as saltwater representative fish in an experiment in order to determine the toxicity potential of the calcium sulfonate read-across substance (CAS 70024-71-4) (Nicholson, 1986b). The acclimatisation period was about 13 days and the biomass loading rate was 0.056 g/L. A control group was included and a single concentration of 10000 mg/L WAF was applied (limit test). The exposure time was 96 h. Sodium lauryl sulfate was used as reference substance, revealing a LC50(96h) of 1.2 mg/L. Neither in the control nor in any of the treatment groups, mortality or signs of toxicity were recorded. Therefore, the LL50(96h) is > 10000 mg/L WAF with a corresponding NOELR of 10000 mg/L WAF. No statistical analysis of data was warranted due to the fact that the test substance was found to be non-toxic under the applied conditions.

These results can be used to fulfill the information requirements for the chemical substance Reaction products of benzenesulfonic acid, mono-C20-24 (even)-sec-alkyl derivs. para-, calcium salts, due to the high structural similarity of these substances. For the detailed procedure of the read-across principle and justifications, please refer to the separate Read-Across Statement (Chemservice S.A., 2017).

Reference 3

Endpoint:

short-term toxicity to fish

Type of information:

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

Adequacy of study:

key study

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
In this justification, the read-across (bridging) concept is applied, based on the chemical structure of the potential analogues, their toxicokinetic behaviour and other available (eco-)toxicological data.

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
C20-24 calcium sulfonate and Sulfonic acids, petroleum, calcium salts (CAS 61789-86-4) are members of a category of chemicals described as alkaryl sulfonates, which was established as part of the U.S. Environmental Protection Agency High Production Volume (HPV) Challenge Program. The substances of this category have a common functional group - the salt of aryl sulfonic acid. Furthermore, they all have a divalent alkaline earth metal, one or more linear and/or branched alkyl groups of variable chain length and branching characteristics or extended heterocyclic carbon system from the sulfonated benzene ring. Finally, they have common precursors and/or the likelihood of common breakdown products via physical and biological processes, resulting in structurally similar chemicals, and similar physicochemical properties, environmental fate, ecotoxicity and mammalian toxicity.
Concerning short-term toxicity to fish, it is believed that both substance will be metabolised by the same mechanisms by microorganisms and by other classes of living organisms. Therefore they are expected to follow the same pattern. For the detailed procedure of the read-across principle and justifications, please refer to the analogue approach justification depicted below and the separate Read-Across Statement (Chemservice S.A., 2017).

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
Source chemical: Sulfonic acids, petroleum, calcium salts (CAS 61789-86-4, EC 263-093-9)
Target chemical: Reaction products of benzenesulfonic acid, mono-C20-24 (even)-sec-alkyl derivs. para-, calcium salts (C20-24 calcium sulfonate, CAS No none, EC No none)

3. ANALOGUE APPROACH JUSTIFICATION
C20-24 calcium sulfonate and Sulfonic acids, petroleum, calcium salts (CAS 61789-86-4) are UVCB substances that are produced using similar manufacturing process and raw materials and are manufactured in mineral oil. They are members of a category of chemicals described as alkaryl sulfonates, which was established as part of the U.S. Environmental Protection Agency High Production Volume (HPV) Challenge Program. These substances are similar in that they have a common functional group, the salt of aryl sulfonic acid. TOXMATCH and OECD Toolbox QSAR structure similarity assessments using Tanimoto distance fingerprint, Hellinger distance atom environment, Euclidian distance and Dice calculations indicate that these substances are only similar to a certain extent. However, a certain difference can be expected due to the presence of additional benzene rings and a significantly increased amount of secondary alkylations. They have similar physicochemical properties, similar environmental fate characteristics, and similar ecotoxicity and mammalian toxicity profiles. For example, these substances can dissociate only in the presence of strong acids such as in the stomach but are not expected to dissociate under environmental conditions. For further details on this, please refer to the separate Read-Across Statement (Chemservice S.A., 2017). The similar toxicity profiles indicate that they have a similar MOA. C20-24 calcium sulfonate and Sulfonic acids, petroleum, calcium salts (CAS 61789-86-4) are both not classified for environmental toxicity.
The similar findings (refer to data matrix outlined below and the separate Read-Across Statement) for both substances support the conclusion that similar molecules are expected to be formed from both substances, and in consequence, similar effects can be reasonably expected. Hence, the analogue may serve in a worst case approach as a read-across substance for the C20-24 calcium sulfonate. So, based on the WOE of these data, the available data on CAS 61789-86-4 can be used to cover the systemic endpoints currently lacking for C20-24 calcium sulfonate and read across is scientifically justified, making further testing obsolete.

4. DATA MATRIX
There is mainly data available on the toxicological properties of the analogues CAS 61789-86-4 / its overbased version CAS 68783-96-0 and for CAS 70024-69-0 / its overbased version CAS 70024-71-4. Data on Reaction products of benzenesulfonic acid, mono-C20-24 (even)-sec-alkyl derivs. para-, calcium salts covers merely the physico chemical properties. Hence, the identification and discussion of common properties of the analogues and the C20-24 calcium sulfonate will be mainly based on this physicochemical data.
The available data for the following physico-chemical properties, which are relevant for absorption into living organisms, are very similar. The substances are rather huge molecules and have a similar molecular weight range, which triggers already similarities in their absorption/adsorption and desorption behaviour. Furthermore, the physico-chemical properties like their partition coefficient, water solubility and vapour pressure are similar. Regarding the application of these substances, the substances are usually solved in an inert mineral oil to enable handling. The C20-24 calcium sulfonate and all analogous substances are hydrolytically stable in the natural environment, as they do not contain hydrolysable groups. In addition, at least CAS 70024-69-0 and CAS 61789-86-4 are not readily biodegradable, and the available data suggests this to apply also for C20-24 calcium sulfonate. Taking into account the vast amount of data available for partition coefficient data on various calcium sulfonates it can be concluded that they do not have a significant potential for bioaccumulation in aquatic and terrestrial organisms. However, they are expected to be adsorbed to a significant extent to the sediment and soil and to be thereby not bioavailable, which was confirmed by the results of short-term toxicity tests to fish, daphnia and algae for CAS 70024-71-4; CAS 115733-09-0 and CAS 61789-64-4, in which the lowest LL50 was already > 100 mg/L WAF.
For the following toxicological endpoints there is data available derived from CAS 70024-69-0/ CAS 70024-71-4, Analogue of CAS 70024-69-0, CAS 115733-09-0, CAS 61789-86-4/ CAS 68783-96-0 and CAS 75975-85-8: Acute toxicity, Skin irritation / corrosion, Eye irritation /corrosion, Skin sensitization, Repeated dose toxicity, Genetic toxicity in vitro and in vivo and Toxicity to reproduction (fertility / developmental toxicity). Furthermore a rather extensive data package is available concerning the human sensitization potential of numerous analogous substances. For the acute oral toxicity, the values for all read across substances are very high, all LD50 values being above 2000 mg/kg (reaching in older tests up to greater than 20,000 mg/kg) and the values for the substances can be considered as similar within normal biological variations. The substances are also not toxic via the inhalation or the dermal route of exposure. Regarding Skin/Eye Irritation, the available data on CAS 70024-69-0 and CAS 61789-86-4 shows both substances to be not irritating to the skin or the eyes. The skin sensitization data in animals and humans (for CAS 75975-85-8; CAS 61789-86-4 and EC 939-141-6) evaluated in a weight-of-evidence approach indicates that low TBN calcium sulfonates (TBN < 300) are skin sensitizers with a specific concentration limit (SCL) of 10% and that high TBN calcium sulfonates (TBN ≥ 300) are not skin sensitizers. Last but not least, the available genetic toxicity data for Analogue of CAS 70024-69-0, CAS 61789-86-4 and its overbased version CAS 68783-96-0 prove all of these substances to be not mutagenic. The NOAELs derived for the endpoints Repeated dose toxicity (Analogue of CAS 70024-69-0 and CAS 61789-86-4) and Toxicity to reproduction (fertility / developmental toxicity for CAS 115733-09-0)) have been also found to be in a similar range.
For further details please refer to the separate Read-Across Statement (Chemservice S.A., 2017) and/or the robust study summaries of the respective studies in this IUCLID file.

Reason / purpose for cross-reference:

read-across source

Duration:

96 h

Dose descriptor:

LL0

Effect conc.:

10 000 other: mg/L WAF

Nominal / measured:

nominal

Conc. based on:

other: WAF loading rate

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

LL50

Effect conc.:

> 10 000 other: mg/L WAF

Nominal / measured:

nominal

Conc. based on:

other: WAF loading rate

Basis for effect:

mortality (fish)

Details on results:

Control mortality did not exceed the test validity criterion (i.e. < 10 % mortality in controls).
No mortality or signs of toxicity were noted in either the control or the 10000 mg/L WAF treatment throughout the test.

Results with reference substance (positive control):

96 hour LC50 was 1.2 mg/L

Reported statistics and error estimates:

Statistical analysis of the data was not warranted on the basis that no mortality occurred in this study.

Validity criteria fulfilled:

yes

Remarks:

Scientifically validity criteria were met.

Conclusions:

The report describes a valid guideline study with GLP compliance. The calcium sulfonate Read-Across substance (CAS 61789 -86 -4) was found to be not toxic for Sheepshead minnow (Cyprinidon variegatus) at a loading of 10000 mg/L nominal WAF. These results can be used to fulfill the information requirements for the chemical substance Reaction products of benzenesulfonic acid, mono-C20-24 (even)-sec-alkyl derivs. para-, calcium salts, due to the high structural similarity of these substances. For the detailed procedure of the read-across principle and justifications, please refer to the separate Read-Across Statement (Chemservice S.A., 2017).

Executive summary:

In a 96-hour acute toxicity study, Sheepshead minnow (Cyprinidon variegatus) were exposed to sulphonic acid, petroleum derived calcium salt (CAS 61789 -86 -4) at nominal concentrations of 0 and 10,000 mg/L WAF under static renewal conditions.  The 96-hour LL₅₀was >10,000 mg/L nominal WAF. No signs of toxicity were noted.

 

This toxicity study is classified as acceptable and satisfies the guideline requirement for a fish acute toxicity study.

 

Results Synopsis

 

Test organism size/age (mean wet weight or length): 14 days old, average length 12 mm, average weight 0.04 g

Test Type: Static renewal

 

LL₅₀:  >10,000 mg/L nominal WAF

LL₀:  10,000 mg/L nominal WAF

Endpoint(s) Effected: None

These results can be used to fulfill the information requirements for the chemical substance Reaction products of benzenesulfonic acid, mono-C20-24 (even)-sec-alkyl derivs. para-, calcium salts, due to the high structural similarity of these substances. For the detailed procedure of the read-across principle and justifications, please refer to the separate Read-Across Statement (Chemservice S.A., 2017).

Description of key information

Acute toxicity to freshwater fish:
No toxicity observed even at highest concentration level tested.
RA_CAS115733-09-0_OECD 203_Oncorhynchus mykiss: LL50(96h) > 100 mg/L WAF

Acute toxicity to saltwater fish:
No toxicity observed even at highest concentration level tested.

RA_CAS70024-71-4_OECD 203_Cyprinodon variegatus: LL50 (96h) > 10000 mg/L WAF,

RA_CAS61789-86-4_OECD 203_Cyprinodon variegatus: LL50 (96h) > 10000 mg/L WAF

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

100 mg/L

Marine water fish

Marine water fish

Effect concentration:

10 000 mg/L

Additional information

General considerations

The acute toxicity to fish was investigated for different analogues structures of the calcium sulfonate target substance (Reaction products of benzenesulfonic acid, mono-C20-24 (even)-sec-alkyl derivs. para-, calcium salts). For the substance itself, no experimental data are available. Since all substances used belong to the same chemical group, aryl-alkyl sulfonates, the same behaviour and toxicity potential can be expected. Calcium sulfonate read-across substance (CAS 115733-09-0), calcium sulfonate read-across substance (CAS 61789 -86 -4) and calcium sulfonate read-across substance (CAS 70024-71-4), were used to fulfil the endpoint of short-term toxicity to freshwater fish: For the detailed procedure of the read-across principle and justifications, please refer to the separate Read-Across Statement (Chemservice S.A., 2017).

Acute toxicity to freshwater fish

In a 96-hour key study, juvenile Rainbow trouts (Oncorhynchus mykiss) were exposed to the calcium sulfonate read-across substance (CAS 115733-09-0) at nominal concentrations of 0 (control group) and 100 mg/L WAF loading rate under semi-static conditions (Goodband, 2005).

The experiment was conducted in accordance to OECD Guideline 203 and under GLP compliance. Based on the intrinsic properties of the used substance, Water Accommodated Fractions (WAFs) were prepared for testing. Physico-chemical parameters (i.e. water temperature, pH and dissolved oxygen concentration (DOC)) were recorded daily throughout the test duration of 96 h. No mortalities and no sublethal effects were noted at the highest tested concentration, thus the LL50(96h) is reported to be > 100 mg/L WAF with a corresponding NOELR of 100 mg/L WAF.

Acute toxicity to saltwater fish

Cyprinodon variegatus (Sheepshead minnow) was used as saltwater representative fish in an experiment in order to determine the toxicity potential of the calcium sulfonate read-across substance (CAS 70024-71-4) in a key study by Nicholson (1986b). The acclimatisation period was about 13 days and the biomass loading rate was 0.056 g/L. A control group was included and a single concentration of 10000 mg/L WAF was applied (limit test). The exposure time was 96 h. Sodium lauryl sulfate was used as reference substance, revealing a LC50 (96h) of 1.2 mg/L. Neither in the control nor in any of the treatment groups, mortality or signs of toxicity were recorded. Therefore, the LL50 (96h) is > 10000 mg/L WAF with a corresponding NOELR of 10000 mg/L WAF. No statistical analysis of data was warranted due to the fact that the test substance was found to be non-toxic under the applied conditions.

In a further key study (Nicholson, 1986a), calcium sulfonate read-across substance (CAS 61789-86-4) was tested under same test conditions (i.e. Shepshead minnow; 96 h exposure according to OECD Guideline 203; single concentration level of 10000 mg/L WAF). Again, no toxic effects were observed at this concentration level. Hence, the LL50(96h) is > 10000 mg/L WAF, whereas NOELR amounts to 10000 mg/L WAF.

Conclusion:

No toxic effects observed in all acute fish studies even at the highest concentration levels tested. The weight-of-evidence indicate that the lower NOECs for O. mykiss are not an indicator of toxicity per se, but are the result of dose selection.