Sodium benzenesulphinate

Endpoint summary

Description of key information

Short term toxicity on aquatic invertebrates

Using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the five closest read across substances, the short term toxicity on aquatic invertebrates was predicted for sodium benzenesulfinate (873-55-2). EC50 value was estimated to be 130.5 mg/l for Daphnia magna for 48 hrs duration. Based on the value, sodium benzenesulfinate (873-55-2) was considered to be non-toxic to aquatic invertebrates and can be considered to be not classified as per the CLP regulations.

Toxicity to aquatic algae and cyanobacteria

Using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the five closest read across substances, the short term toxicity on aquatic algae and cyanobacteria was predicted for target substance sodium benzenesulfinate (CAS no. 873 -55 -2). EC50 value was estimated to be 105.25 mg/l for Pseudokirchneriella subcapitata for 72 h duration. Based on this value it can be concluded that the substance sodium benzenesulfinate is considered to be non-toxic to aquatic environment and can be considered to be not classified as per the CLP classification criteria.

Toxicity to microorganisms

Antibacterial and antifungal activities of sulfone derivatives including test compound sodium benzenesulfinate was tested for four bacterial strains (two gram positive, and two gram negative ones) and two yeasts by Disk diffusion method.

The minimal inhibitory concentration (MIC) value of the test compound sodium benzenesulfinate was observed at dose concentration 10 μl/disk in DMSO for 30 min. The test compound showed no activity against any of the tested strains (i.e Staphylococcus aureus,Escherichia coli,Candida albicans,Candida tropicalis,Pseudomonas aeruginosa and Enterococcus hirae) whereas the zone of inhibition for the positive controls are in the range 14-34 mm.

Thus, NOEC for the substance can be considered to be 10 μl/disk for 30 minute study.

Additional information

Short term toxicity to aquatic invertebrates

Short term toxicity to aquatic invertebrates for sodium benzenesulfinate (873-55-2) was summaries with predicted data for target and experimental studies of read across are summarised as follows:

Using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the five closest read across substances, the short term toxicity on aquatic invertebrates was predicted for sodium benzenesulfinate (873-55-2). EC50 value was estimated to be 130.5 mg/l for Daphnia magna for 48 hrs duration. Based on the value, sodium benzenesulfinate (873-55-2) was considered to be non-toxic to aquatic invertebrates and can be considered to be not classified as per the CLP regulations.

Study was performed according to the OECD guideline 202 on read across sodium ethenesulfonate (3039-83-6) from IUCLID dataset (2000).The test was performed for 48 hrs After the experiment, the EC 50 value for sodium ethenesulfonate (3039-83-6) for short term toxicity to daphnia magna was determined to be >100 mg/l. Based on the value, sodium ethenesulfonate (3039-83-6) was considered to be non-toxic to aquatic invertebrates and can be considered to be not classified as per the CLP regulations.

Information for another read across benzenesulfonic acid (98-11-3) from IUCLID dataset, NOTOX Company, (2003) indicate that study was performed according to the OECD guideline 202. The test was performed for 48 hrs in daphnia magna. After the experiment, the EC 50 value for benzenesulfonic acid (98-11-3) for short term toxicity to aquatic invertebrates was determined to be 963000 mg/l. Based on the value, benzenesulfonic acid (98-11-3) was considered to be non-toxic to aquatic invertebrates and can be considered to be not classified as per the CLP regulations.

Based on the above prediction of target and studies of functional read across, it was considered that sodium benzenesulfinate (873-55-2) was non-toxic to aquatic invertebrates and can be considered to be not classified as per the CLP regulation.

Toxicity to aquatic algae and cyanobacteria

Various predicted data for the target chemical sodium benzenesulfinate(CAS No. 873-55-2) and various weight of evidence study for its read across substance were reviewed to summarize the following information:

Short term toxicity on aquatic algae and cyanobacteria of target chemical sodium benzenesulfinate(CAS No. 873-55-2) is predicted using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the five closest read across substances (2017). EC50 value was estimated to be 105.25 mg/l for Pseudokirchneriella subcapitata for 72 h duration. Based on this value it can be concluded that the substance sodium benzenesulfinate is considered to be non-toxic to aquatic environment and can be considered to be not classified as per the CLP classification criteria.

 

In a weight of evidence study from authoritative database (ECOTOX, 2017) of the read across chemical Benzenesulphonic acid (CAS no. 98 -11 -3),short term toxicity to Navicula seminulum (Pennate diatom) study was carried out for 96 hrs. The study was based on the effects of the read across compound Benzenesulphonic acid on Navicula seminulum in a static fresh water system at a temperature of 28°C and hardness of 77 mg/l as CaCO3 respectively. Based on effect on population of the test organism Navicula seminulum, the 96 hr EC50 value was determined to be 19500 mg/l, respectively. Thus, based on the EC50 value, it can be concluded that the substance Benzenesulphonic acid can be considered as non-toxic to aquatic organisms and thus can be considered to be not classified as per the CLP classification criteria.

 

Another short term toxicity to Selenastrum capricornutum (green algae) study was carried out for 72 hrs (HPVIS, 2016). The study was performed according to OECD Guideline 201 (Alga, Growth Inhibition Test) and was based on the effects of the read across compound Benzenesulphonic acid (CAS no. 98 -11 -3) on Selenastrum capricornutum in a static fresh water system under a continuous illumination with a light intensity within the range of 73 to 101 uE/m2/s, at a temperature of 22.5 - 23°C, pH of 8.3 ± 0.2 and hardness of 24 mg/l as CaCO3 respectively. Pretreatment was given to the test organism for 3 days under test conditions. Test chemical concentration used for the study was 0, 4.6, 10, 22, 46, 100 and 220 mg/L (nominal concentration) and 0 (not detected), 4.3, 10.1, 21.9, 44.8, 101, 224 and 233 mg/l (measured concentration), respectively. A stock solution of 220 mg/L was prepared in test medium, applying 56 minutes of magnetic stirring. Lower test concentrations were prepared by subsequent dilutions of the stock in test medium. Analytical determinations were carried out using HPLC (RP, UV detection at 263 nm). Potassium dichromate was used as a reference substance in the study. All tests were performed in triplicates except the blank control was performed in 6 replicates. Inhibition of cell growth and reduction of growth rate was measured at 0 hr and 72 hr. Based on effect on cell growth inhibition and growth rate reduction of the test organism Selenastrum capricornutum, the 72 hr NOEC value was determined to be 46 mg/l and on the basis of effect on cell growth inhibition and growth rate reduction, the 72 hr EC50 value was determined to be 70 and 73 mg/l, respectively. Thus, based on the EC50 value, it can be concluded that the substance Benzenesulphonic acid can be considered as toxic to aquatic organisms. Since the chemical is readily biodegradable in nature, chemical Benzenesulphonic acid can be considered as non-toxic to aquatic organisms and thus can be considered to be not classified as per the CLP classification criteria.

 

Thus, based on the overall reported results for target chemicalsodium benzenesulfinate(OECD QSAR toolbox version 3.3, 2017) and for its read across substance (from authoritative database ECOTOX, 2017 and secondary source HPVIS, 2016), it can be concluded that the test substancesodium benzenesulfinatecan be considered asnon-toxic to aquatic environment and can be considered to be not classified as per the CLP classification criteria.

Toxicity to microorganisms

By Disk diffusion method, antibacterial and antifungal activities of sulfone derivatives including test compound sodium benzenesulfinate was tested for four bacterial strains (two gram positive, and two gram negative ones) and two yeasts.

In Disk diffusion method; paper disk containing title comp. placed on Mueller-Hinton agar plate inoculated with test bacteria ATCC 6538, bacteria ATCC 10536, bacteria ATCC 15442, bacteria ATCC 10541, fungi ATCC 90029,fungi ATCC 90029, strain and incubated at 37 deg C; diameter of inhibition zone measured as follows:

The zone of inhibition for the positive controls are in the range 14-34 mm as mentioned below:

-For Staphylococcus aureus-streptomycin with 27 mm inhibition zone as positive control

-For Escherichia coli-chloramphenicol with 34 mm inhibition zone as positive control

-For Candida albicans-fluconazole with 18 mm inhibition zone as positive control

-For Candida tropicalis-fluconazole with 21 mm inhibition zone as positive control

-For Pseudomonas aeruginosa-penicillin G with 24 mm inhibition zone as positive control

-For Enterococcus hirae-penicillin G with 14 mm inhibition zone as positive control

According to the disk diffusion method, the minimal inhibitory concentration (MIC) value of the test compound sodium benzenesulfinate was determined at dose concentration 10 μl/disk in DMSO for 30 min. The test compound showed no activity against any of the tested strains (i.e Staphylococcus aureus,Escherichia coli,Candida albicans,Candida tropicalis,Pseudomonas aeruginosa and Enterococcus hirae). Thus, NOEC for the substance can be considered to be 10 μl/disk for the 30 minute study