Sodium tris(1,2-naphthoquinone 1-oximato-O,O')ferrate(1-)

PBT assessment

PBT assessment: overall result

PBT status:

the substance is not PBT / vPvB

Justification:

Classification of Sodium tris(1,2-naphthoquinone 1-oximato-O,O')ferrate(1-) for effects in the environment:

 

The chemical Sodium tris(1,2-naphthoquinone 1-oximato-O,O')ferrate(1-) (CAS no. 16143-80-9) is used in the dyestuff industry. The aim was to assess whether the PBT criterion within Annex XIII was fulfilled for Sodium tris(1,2-naphthoquinone 1-oximato-O,O')ferrate(1-). 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 logKow as the primary descriptor, percentage biodegradability of test chemical, Sodium tris(1,2-naphthoquinone 1-oximato-O,O')ferrate(1-)(CAS No. 16143-80-9)was estimated.Test substance undergoes 19.6% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical Sodium tris(1,2-naphthoquinone 1-oximato-O,O')ferrate(1-) was estimated to be not readily biodegradable in water.

 

Experimental study on read across substances (CAS: 2611-82-7; 3864-99-1 and 3896-11-5) also indicate the substances to be not readily biodegradable.

 

Environmental fate

According to the fugacity model levels III, the most likely environmental fate for this test chemical is sediment (i.e.estimated to 68.4%).The half-life in sediment (541.6 days estimated by EPI suite) indicates that the chemical is persistent in sediment.

 

If released in to the environment, 30.3% and 1.28 % of the chemical will partition into soil and water, respectively according to the Mackay fugacity model level III in EPI suite version 4.1 (2016). However, the half-life (120 days in soil and 60 days in water as estimated by EPI suite) indicates that the substance is not persistent in soil but persistent in water.

 

Although the half-life values in sediment suggest classification as very persistent (vP), the substance is classified only as persistent (P) since only estimated half-life values are available for the same.

 

Hence it has been concluded that the substance Sodium tris(1,2-naphthoquinone 1-oximato-O,O')ferrate(1-) is persistent in nature.  

 

Bioaccumulation assessment

The tested substance fulfils the B criterion within Annex XIII based on the assessment that here follows:

 

The octanol water partition coefficient of the test chemical is in the range 5.63 which is more than the threshold of 4.5. If this chemical is released into the aquatic environment, there should be a moderate 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

As per Column 2 (Annex VIII) of the REACH regulation, a study does not need to be conducted if there are mitigating factors indicating that aquatic toxicity is unlikely to occur for instance if the substance is highly insoluble in water. The test substance was determined to be highly insoluble in water. 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 fulfils the P and B criterion but does not fulfil the T criterion and has therefore not been classified as a PBT compound within Annex XIII.