Dipotassium 4,4'-bis[6-anilino-4-[bis(2-hydroxyethyl)amino-1,3,5-triazin-2-yl]amino]stilbene-2,2'-disulphonate

PBT assessment

PBT assessment: overall result

PBT status:

the substance is not PBT / vPvB

Justification:

Classification of Dipotassium 4,4'-bis[6-anilino-4-[bis(2-hydroxyethyl)amino-1,3,5-triazin-2-yl]amino]stilbene-2,2'-disulphonate for effects in the environment:

 

The chemical Dipotassium 4,4'-bis[6-anilino-4-[bis(2-hydroxyethyl)amino-1,3,5-triazin-2-yl]amino]stilbene-2,2'-disulphonate (CAS no. 71230-67-6) is used in as an optical brightening agent for paper and textiles. The aim was to assess whether the PBT criterion within Annex XIII was fulfilled for Dipotassium 4,4'-bis[6-anilino-4-[bis(2-hydroxyethyl)amino-1,3,5-triazin-2-yl]amino]stilbene-2,2'-disulphonate. 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 fulfils the P criterion within Annex XIII based on the assessment that here follows:

 

Biotic degradation

In a prediction done by SSS (2017) using OECD QSAR toolbox version 3.3 with log Kow as the primary descriptor, percentage biodegradability of test chemical Dipotassium 4,4'-bis[6 -anilino-4 -[bis(2 -hydroxyethyl)amino-1,3,5 -triazin-2 -yl]amino]stilbene-2,2'-disulphonate (CAS No. 71230-67-6) was estimated. Test substance undergoes 1.55% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical Dipotassium 4,4'-bis[6-anilino-4-[bis(2-hydroxyethyl)amino-1,3,5-triazin-2-yl]amino]stilbene-2,2'-disulphonate was estimated to be not readily biodegradable in water.

 

Experimental results from the similar substances (CAS: 16090-02-1; 4404-43-7; 4193-55-9 and 16470-24-9) also indicate that they are not readily biodegradable

 

Environmental fate

According to the fugacity model levels III, the most likely environmental fate for this test chemical is sediment and soil (i.e.estimated to 59.1 and 40.2% respectively). In soil, Dipotassium 4,4'-bis[6-anilino-4-[bis(2-hydroxyethyl)amino-1,3,5-triazin-2-yl]amino]stilbene-2,2'-disulphonate was expected to have negligible mobility based upon a LogKOC in the range 6.9 – 9.9. Thehalf-life (1620.8 days in sediment and 360 days in soil estimated by EPI suite) indicates that the chemical is persistent in both the compartments.

 

If released in to the environment, 0.684% of the chemical will partition into water according to the Mackay fugacity model level III in EPI suite version 4.1 (2017). However, the half-life (180 days in water as estimated by EPI suite) indicates that the substance is persistent in the medium.

 

Although the half-life values indicate the chemical to be Very persistent (vP), since only predicted data is available for the substance, it has been concluded that Dipotassium 4,4'-bis[6-anilino-4-[bis(2-hydroxyethyl)amino-1,3,5-triazin-2-yl]amino]stilbene-2,2'-disulphonate 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:

 

Theestimated BCF value from authoritative database was determined to be 3-3.162 and theoctanol water partition coefficient of the test chemical is 0.9539 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 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 not classified as per the CLP regulation.

 

There are no available long-term toxicity evaluations for Dipotassium 4,4'-bis[6-anilino-4-[bis(2-hydroxyethyl)amino-1,3,5-triazin-2-yl]amino]stilbene-2,2'-disulphonate. 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 fulfil the P criterion but does not fulfil the B and T criterion and has therefore not been classified as a PBT compound within Annex XIII.