Sulphoacetic acid

Endpoint summary

Description of key information

Dermal Irritation:

The dermal irritation potential of sulfoacetic acid was estimated using OECD QSAR toolbox v3.3 with logPow as the primary descriptor.

Sulfoacetic acid was estimated to be severely irritating to the skin of Vienna White rabbits.

Based on the estimated results, Sulfoacetic acid can be considered to be severely irritating to skin and can be classified under the category “Category 1” as per CLP regulation.

Eye Irritation:

Sulfoacetic acid was rated 9 on a scale of 1-10. Most severe injuries are rated 10

Hence based on the scores, sulfoacetic acid can be considered severely irritating to rabbit eyes.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Endpoint:

skin irritation: in vivo

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with limited documentation / justification

Justification for type of information:

data is from OECD QSAR toolbox v3.3 and the QMRF report has been attached

Qualifier:

according to guideline

Guideline:

other: Estimated data

Principles of method if other than guideline:

Prediction was done using OECD QSAR toolbox v3.3

GLP compliance:

not specified

Specific details on test material used for the study:

- Name of test material: Sulfoacetic acid
- Molecular formula: C2H4O5S
- Molecular weight: 140.115g/mole
- Substance type: organic
- Physical state: solid

Species:

rabbit

Strain:

Vienna White

Details on test animals or test system and environmental conditions:

no data available

Type of coverage:

open

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

not specified

Amount / concentration applied:

100%

Duration of treatment / exposure:

3 hours

Observation period:

8 days

Number of animals:

2

Details on study design:

no data available

Other effects / acceptance of results:

no data available

Irritation parameter:

overall irritation score

Basis:

mean

Time point:

other: 8 days

Reversibility:

not specified

Remarks on result:

probability of severe irritation

Irritant / corrosive response data:

Severe irritation observed

Estimation method: Takes mode value from the 5 nearest neighbours
Domain  logical expression:Result: In Domain

((((((("a" or "b" or "c" or "d" or "e" )  and "f" )  and ("g" and ( not "h") )  )  and "i" )  and "j" )  and "k" )  and ("l" and "m" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as Anionic Surfactants by US-EPA New Chemical Categories

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as Carboxylic acid AND Sulfonic acid by Organic Functional groups

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as Carboxylic acid AND Overlapping groups AND Sulfonic acid by Organic Functional groups (nested)

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as Acid, aliphatic attach [-COOH] AND Alcohol, olefinic attach [-OH] AND Aliphatic Carbon [CH] AND Aliphatic Carbon [-CH2-] AND Carbonyl, aliphatic attach [-C(=O)-] AND Hydroxy, sulfur attach [-OH] AND Miscellaneous sulfide (=S) or oxide (=O) AND Olefinic carbon [=CH- or =C<] AND Suflur {v+4} or {v+6} AND Sulfinic acid [-S(=O)OH] AND Sulphonate, aliphatic attach [-SO2-O] by Organic functional groups (US EPA)

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as Carbonic acid derivative AND Carboxylic acid AND Carboxylic acid derivative AND Sulfonic acid AND Sulfonic acid derivative by Organic functional groups, Norbert Haider (checkmol)

Domain logical expression index: "f"

Referential boundary: The target chemical should be classified as Bioavailable by Lipinski Rule Oasis ONLY

Domain logical expression index: "g"

Referential boundary: The target chemical should be classified as Group 14 - Carbon C AND Group 16 - Oxygen O AND Group 16 - Sulfur S by Chemical elements

Domain logical expression index: "h"

Referential boundary: The target chemical should be classified as Group 1 - Alkali Earth Li,Na,K,Rb,Cs,Fr OR Group 12 - Trans.Metals Zn,Cd,Hg OR Group 15 - Nitrogen N OR Group 15 - Phosphorus P OR Group 17 - Halogens Cl OR Group 17 - Halogens F,Cl,Br,I,At OR Group 2 - Alkaline Earth Be,Mg,Ca,Sr,Ba,Ra OR Group 4 - Trans.Metals Ti,Zr,Hf OR Group 7 - Trans.Metals Mn,Tc,Re by Chemical elements

Domain logical expression index: "i"

Similarity boundary:Target: OC(=O)CS(O)(=O)=O
Threshold=20%,
Dice(Atom centered fragments)
Atom type; Count H attached; Hybridization

Domain logical expression index: "j"

Similarity boundary:Target: OC(=O)CS(O)(=O)=O
Threshold=30%,
Dice(Atom centered fragments)
Atom type; Count H attached; Hybridization

Domain logical expression index: "k"

Similarity boundary:Target: OC(=O)CS(O)(=O)=O
Threshold=40%,
Dice(Atom centered fragments)
Atom type; Count H attached; Hybridization

Domain logical expression index: "l"

Parametric boundary:The target chemical should have a value of log Kow which is >= -1.4

Domain logical expression index: "m"

Parametric boundary:The target chemical should have a value of log Kow which is <= 1.56

Interpretation of results:

Category 1 (corrosive) based on GHS criteria

Conclusions:

Sulfoacetic acid was estimated to be severely irritating to the skin of Vienna White rabbits.

Executive summary:

The dermal irritation potential of sulfoacetic acid was estimated using OECD QSAR toolbox v3.3 with logPow as the primary descriptor.

Sulfoacetic acid was estimated to be severely irritating to the skin of Vienna White rabbits.

Based on the estimated results, Sulfoacetic acid can be considered to be severely irritating to skin and can be classified under the category “Category 1” as per CLP regulation.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Eye irritation

Link to relevant study records

Reference

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Justification for type of information:

data is from authoritative databases

Qualifier:

according to guideline

Guideline:

other: as mentioned below

Principles of method if other than guideline:

To assess the ocular irritation potential of sulfoacetic acid in rabbits

GLP compliance:

not specified

Specific details on test material used for the study:

- Name of test material: Sulfoacetic acid
- Molecular formula: C2H4O5S
- Molecular weight: 140.115g/mole
- Substance type: organic
- Physical state: solid

Species:

rabbit

Strain:

not specified

Details on test animals or tissues and environmental conditions:

no data available

Vehicle:

unchanged (no vehicle)

Controls:

not specified

Amount / concentration applied:

no data available

Duration of treatment / exposure:

24 hours

Observation period (in vivo):

24 hours

Duration of post- treatment incubation (in vitro):

no data available

Number of animals or in vitro replicates:

no data available

Details on study design:

SCORING SYSTEM: Ocular reactions were rated on scale of 1 to 10 according to degree of injury observed after 24 hr, paying particular attention to condition of cornea. Most severe injuries have been rated 10.

Other effects / acceptance of results:

no data available

Irritation parameter:

overall irritation score

Basis:

mean

Time point:

24 h

Score:

9

Max. score:

10

Reversibility:

not specified

Remarks on result:

probability of severe irritation

Irritant / corrosive response data:

Severe irritation observed

Interpretation of results:

Category 2 (irritating to eyes) based on GHS criteria

Conclusions:

Sulfoacetic acid was rated 9 on a scale of 1-10. Most severe injuries are rated 10
Hence based on the scores, sulfoacetic acid can be considered severely irritating to rabbit eyes.

Executive summary:

An eye irritation study was carried out in rabbits to assess the eye irritation potential of sulfoacetic acid. Sulfoacetic acid was instilled into rabbit eyes and observed for signs of irritation till 24 hours.Ocular reactions were rated on scale of 1 to 10 according to degree of injury observed after 24 hr, paying particular attention to condition of cornea.

Sulfoacetic acid was rated 9 on a scale of 1-10.Most severe injuries have been rated 10.

Hence based on the scores, sulfoacetic acid can be considered severely irritating to rabbit eyes.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Skin Irritation:

In different studies, sulfoacetic acid has been investigated for potential for dermal irritation to a greater or lesser extent. The studies are based on in vivo experiments in rabbits along with predicted data for target chemical and its functionally similar read across substances, Propionic acid [CAS: 79-09-4] and 2-methoxyacetic acid [CAS: 625-45-6].The predicted data using the OECD QSAR toolbox has also been compared with the experimental data.

In a prediction done by SSS (2017) using the OECD QSAR toolbox with log kow as the primary descriptor, the dermal irritation potential was estimated for sulfoacetic acid. Sulfoacetic acid was estimated to be severely irritating to the skin of Vienna White rabbits.

The dermal irritation potential of sulfoacetic acid was assessed (RTECS, Registry of Toxic Effects of Chemical Substances, last updated 1997) in rabbits according to Standard Draize test. 20 mg of sulfoacetic acid was applied on to the skin of rabbits. The rabbits were exposed to the test chemical for 24 hours and observed for signs of irritation. Sulfoacetic acid was moderately irritating to rabbit skin after 24 hours of exposure.

Hence, sulfoacetic acid can be considered to be moderate dermal irritant.                        

Skin irritation effects were also estimated by four different models i.e, Battery, Leadscope, SciQSAR and CASE Ultra used within Danish QSAR database for sulfoacetic acid. Based on estimation, severe skin irritation effects were known when sulfoacetic acid was exposed to rabbit skin. Hence, sulfoacetic acid can be considered to be irritating to skin.

The experimental and estimated results are in agreement with each other indicating the possibility of sulfoacetic acid being severely irritating to skin.

These results are further supported by the experimental study summarized in American Industrial Hygiene Association Journal, 1962, 23:2, 95-107; for the functionally similar read across substance, Propionic acid [CAS: 79-09-4]. Primary skin irritation on rabbits was recorded in a 10-grade ordinal series and was based upon the severest reaction that developed on the clipped abdominal skin of each of five albino rabbits within 24 hours of the uncovered application of 0.01 ml of undiluted sample. Grade 1 indicates no irritation and Grade 2 the least visible capillary injection from the undiluted chemical. Grade 6 indicates necrosis when undiluted and Grade 10 indicates necrosis from a 0.01% solution. Propionic acid causes necrosis when applied undiluted to rabbit skin. Primary Irritation score after 24 hours for propionic acid was Grade 6. 

Hence, in the acute dermal irritation study conducted in albino rabbits, propionic acid was considered to be a severe irritant.

These results are also supported by the experimental study summarized in GESTIS - Substance Database (Information system on hazardous substances of the Berufsgenossenschaften); 2017, functionally similar read across substance, 2-methoxyacetic acid [CAS: 625-45-6]. A piece of cotton cloth soaked with 0.5 ml (probably > 10 %) aqueous 2-methoxyacetic acid solution was applied to the shaved dorsal skin of rabbits for 3 minutes or 1 hour. Then the exposed area was rinsed with PEG 400 and finally with 50 % aqueous PEG 400. Exposure for 3 minutes led to slight to severe reddening, whereas contact for 1 hour caused chemical burns (edema, parchment like broken up necrosis). Surviving animals showed only very slow healing of these changes. Hence, 2-methoxyacetic acid can be considered corrosive to rabbit skin.

Based on the available data for the target as well as read across chemicals and applying the weight of evidence approach, sulfoacetic acid can be considered severely irritating to skin.Comparing the above annotations with the criteria of CLP regulation, test chemical can be classified under the category “Category 2”.

Eye Irritation:

In different studies, sulfoacetic acid has been investigated for potential for ocular irritation to a greater or lesser extent. The studies are based on in vivo experiments in rabbits along with predicted data for target chemical and its functionally similar read across substances, Acetic acid [CAS: 64-19-7] and acrylic acid [CAS: 79-10-7].The predicted data using the OECD QSAR toolbox has also been compared with the experimental data.

An eye irritation study was carried out (Hazardous Substances Databank (HSDB), U.S National Library Medicine, last updated 2003) in rabbits to assess the eye irritation potential of sulfoacetic acid. Sulfoacetic acid was instilled into rabbit eyes and observed for signs of irritation till 24 hours. Ocular reactions were rated on scale of 1 to 10 according to degree of injury observed after 24 hr, paying particular attention to condition of cornea.

Sulfoacetic acid was rated 9 on a scale of 1-10.Most severe injuries have been rated 10. Hence based on the scores, sulfoacetic acid can be considered severely irritating to rabbit eyes.

The ocular irritation potential of sulfoacetic acid was assessed (RTECS, Registry of Toxic Effects of Chemical Substances, last updated 1997) in rabbits according to Standard Draize test. 250 microgram of sulfoacetic acid was administration into the eyes of rabbits. The rabbits were exposed to the test chemical for 24 hours and observed for signs of irritation.

Sulfoacetic acid was severely irritating to rabbit eyes after 24 hours of exposure.Hence, sulfoacetic acid can be considered to be severe eye irritant.

In a prediction done by SSS (2017) using the OECD QSAR toolbox with log kow as the primary descriptor, the ocular irritation potential was estimated for sulfoacetic acid. Sulfoacetic acid was estimated to be severely irritating to the eyes of New Zealand White rabbits.

The experimental and estimated results are in agreement with each other indicating the possibility of sulfoacetic acid being severely irritating to eyes.

These results are further supported by the experimental study summarized in Toxicology in Vitro 13 (1999) 73 – 98; for the functionally similar read across substance, Acetic Acid [CAS: 64-19-7]. Draize tests were conducted according to the OECD guidelines for Acetic Acid.

In the first validation, 100 ml aqueous solution or a suspension of the test substances (10%) was applied to the right eyes of 3 male New Zealand white rabbits (2.30±2.98 kg, 13 wk of age). Left eyes remained untreated as a control. Eyes were observed at 1 hr, 4 hr, and every 24 hr thereafter for 7 days. Isotonic sodium chloride solution was also used as a negative control. MAS [Maximum average scores] and scores at 24 hr after application calculated for cornea, iris, conjunctivae and the sum of these scores (total average score) were used for comparison with in vitro data. According to the classification by Kay and Calandra (1962), chemicals can be classified as follows based on their MAS scores: non-irritants = (0≤MAS <0.5), slight irritants = (0.5≤MAS< 15), mild irritants = (15≤MAS< 25), moderate irritants = (25≤MAS <50) and severe irritants  = (50≤MAS) . The Maximum Average Score[MAS] obtained for 10% Acetic acid instilled in rabbits eyes was 32.7 after 24 hours of exposure.

According to the classification based on the MAS scores, Acetic acid can be considered to be moderate eye irritant.

These results are supported by the experimental study summarized in TOXICOLOGY AND APPLIED PHARMACOLOGY, 28,313-319 (1974); for the functionally similar read across substance, acrylic acid [CAS: 79-10-7]. Eye injury in rabbits is recorded in a 10- grade ordinal series and is based upon the degree of corneal necrosis that results from instillation of various volumes and concentrations of chemical. Grade 1 indicates at most a very small area of necrosis resulting from 0.5 ml of undiluted chemical in the eye. Grade 5 indicates a so-called severe burn from 0.005 ml, and Grade 10 indicates a severe burn from 0.5 ml of a 1% solution in water or propylene glycol.

Primary Irritation score after 24 hours for acrylic acid was Grade 9.

In the acute eye irritation study conducted in albino rabbits, acrylic acid was considered to be severely irritating to rabbit eyes.

Based on the available data for the target as well as read across chemicals and applying the weight of evidence approach, sulfoacetic acid can be considered severely irritating to eyes.Comparing the above annotations with the criteria of CLP regulation, test chemical can be classified under the category “Category 2”.

Justification for classification or non-classification

Available studies for sulfoacetic acid indicate that it is likely to cause severe irritation to skin and eyes.

Hence, sulfoacetic acid can be classified under the category “CATEGORY 2” as per CLP regulation