Sulphoacetic acid

PBT assessment

PBT assessment: overall result

PBT status:

the substance is not PBT / vPvB

Justification:

Classification of Sulphoacetic acid for effects in the environment:

 

The chemical Sulphoacetic acid (CAS no. 123-43-3) is used as a laboratory chemicals and as an intermediate for chemical synthesis. The aim was to assess whether the PBT criterion within Annex XIII was fulfilled for Sulphoacetic acid. The PBT criterion was herein assessed based on experimental data in conjunction with standardized environmental fate models. Here follows a description of the PBT assessment.

 

 

Persistence assessment

The tested substance does not fulfil the P criterion within Annex XIII based on the assessment that here follows:

 

Biotic degradation

The biodegradability of test chemical sulphoacetic acid (CAS no. 123 -43 -3) is predicted using OECD QSAR tool box v. 3.3 using log Kow as primary descriptor. Sulfoacetic acid showed 82 % degradation in 28 days using microorganisms as inoculum and BOD as a parameter.

 

In another estimation study using Estimation Programs Interface Suite (EPI suite, 2017), biodegradation potential of the test compound Sulfoacetic acid (CAS No: 123-43-3) was predicted in the presence of mixed populations of environmental microorganisms. The biodegradability of the substance was calculated using seven different models such as Linear Model, Non-Linear Model, Ultimate Biodegradation Timeframe, Primary Biodegradation Timeframe, MITI Linear Model, MITI Non-Linear Model and Anaerobic Model (called as Biowin 1-7, respectively) of the BIOWIN v4.10 software. The results indicate that chemical Sulfoacetic acid (CAS No: 123-43-3) is expected to be readily biodegradable

 

Experimental study on read across substances (CAS: 95-92-1 and 124-04-9) also indicate the substances to be readily biodegradable.

 

Environmental fate

According to the fugacity model levels III, the most likely environmental fate for this test chemical is soil (i.e.estimated to 66.5%). In soil, Sulphoacetic acid was expected to have rapid mobility based upon an estimated Log KOCin the range 0 – 0.65. Thehalf-life in soil (17.33 days estimated by EPI suite) indicates that the chemical is not persistent in soil and the exposure risk to soil dwelling animals is low.

 

If released in to the environment, 33.5% and 0.0592 % of the chemical will partition into water and sediment, respectively according to the Mackay fugacity model level III in EPI suite version 4.1 (2016). However, the half-life (8.66 days in water and 77.91 days in sediment as estimated by EPI suite) indicates that the substance is not persistent in both compartments.

 

Hence it has been concluded that Sulphoacetic acid is not persistent in nature.  

 

Bioaccumulation assessment

The tested substance does not fulfil the B criterion within Annex XIII based on the assessment that here follows:

 

The estimated BCF value from various databases was determined to be in the range 1.0 – 4.63 and theoctanol water partition coefficient of the test chemical is -0.88 which is less than the threshold of 4.5. If this chemical is released into the aquatic environment, there should be a low risk for the chemical to bioaccumulate in fish and food chains.

 

Toxicity assessment

The tested substance does not fulfil the T criterion within Annex XIII based on the assessment that here follows:

 

Mammals

The tested chemical is regarded to be not classified for carcinogenicity, mutagenicity and reprotoxicity, Further, there is no evidence of chronic toxicity, as identified by the classifications STOT (repeated exposure), category 1(oral, dermal, inhalation of gases/vapours, inhalation of dust/mist/fume) or category 2 (oral, dermal, inhalation of gases/vapours, inhalation of dust/mist/fume).

 

Aquatic organisms

All of the available short-term eco-toxicity estimations for fish, invertebrates and algae for the substance indicates the LC50/EC50 value to be >100 mg/L. These value suggest that the substance is likely to be non-hazardous to Aquatic organisms at environmentally relevant concentrations and can be considered to be not classified as per the CLP regulation.

 

There are no available long-term toxicity evaluations for Sulphoacetic acid. By speculation, long-term NOEC for aquatic organisms were not expected for the substance at concentration below 0.01 mg/L based on the data mentioned above.

 

The chemical was therefore not considered as hazardous to aquatic environments as per the criteria set out in Annex XIII.

 

 

Conclusion

Based on critical, independent and collective evaluation of information summarized herein, the tested compound does not fulfil the P, B and T criterion and has therefore not been classified as a PBT compound within Annex XIII.