Chromate(2-), [4-[4-[(5-chloro-2-hydroxyphenyl)azo]-4,5-dihydro-3-methyl-5-oxo-1H-pyrazol-1-yl]benzenesulfonato(3-)][4-[(5-chloro-2-hydroxyphenyl)azo]-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-onato(2-)]-, sodium

PBT assessment

PBT assessment: overall result

PBT status:

the substance is not PBT / vPvB

Justification:

Classification of Chromate(2 -), [4 -[4 -[(5 -chloro-2 -hydroxyphenyl)azo]-4,5 -dihydro-3 -methyl-5 -oxo-1H-pyrazol-1 -yl]benzenesulfonato(3 -)][4 -[(5 -chloro-2 -hydroxyphenyl)azo]-2,4 -dihydro-5 -methyl-2 -phenyl-3H-pyrazol-3 -onato(2 -)]-,sodium for effects in the environment:

 

The aim was to assess whether the PBT criterion within Annex XIII was fulfilled for Chromate(2 -), [4 -[4 -[(5 -chloro-2 -hydroxyphenyl)azo]-4,5 -dihydro-3 -methyl-5 -oxo-1H-pyrazol-1 -yl]benzenesulfonato(3 -)][4 -[(5 -chloro-2 -hydroxyphenyl)azo]-2,4 -dihydro-5 -methyl-2 -phenyl-3H-pyrazol-3 -onato(2 -)]-,sodium (CAS no. 90294 -36 -3). 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

Biodegradability of test chemical Chromate(2 -), [4 -[4 -[(5 -chloro-2 -hydroxyphenyl)azo]-4,5 -dihydro-3 -methyl-5 -oxo-1H-pyrazol-1 -yl]benzenesulfonato(3 -)][4 -[(5 -chloro-2 -hydroxyphenyl)azo]-2,4 -dihydro-5 -methyl-2 -phenyl-3H-pyrazol-3 -onato(2 -)]-, sodium (CAS no. 90294 -36 -3) was estimated by using OECD QSAR tool box v3.4 by considering six closest read across chemical log Kow as primary descriptor. Percent biodegradation of the test chemical Chromate(2 -), [4 -[4 -[(5 -chloro-2 -hydroxyphenyl)azo]-4,5 -dihydro-3 -methyl-5 -oxo-1H-pyrazol-1 -yl]benzenesulfonato(3 -)][4 -[(5 -chloro-2 -hydroxyphenyl)azo]-2,4 -dihydro-5 -methyl-2 -phenyl-3H-pyrazol-3 -onato(2 -)]-, sodium was estimated to be 0.5 % by considering BOD as parameter and Microorganism as inoculum in 28 days. On the basis of percent degradability value it can be concluded that test chemical Chromate(2 -), [4 -[4 -[(5 -chloro-2 -hydroxyphenyl)azo]-4,5 -dihydro-3 -methyl-5 -oxo-1H-pyrazol-1 -yl]benzenesulfonato(3 -)][4 -[(5 -chloro-2 -hydroxyphenyl)azo]-2,4 -dihydro-5 -methyl-2 -phenyl-3H-pyrazol-3 -onato(2 -)]-, sodium is not readily biodegradable.

                                                                 

Experimental results from the read across substances (CAS: 1934-21-0 and 10169-02-5) also indicate that they are not readily biodegradable.

 

As the half-life value of chemical Chromate(2 -), [4 -[4 -[(5 -chloro-2 -hydroxyphenyl)azo]-4,5 -dihydro-3 -methyl-5 -oxo-1H-pyrazol-1 -yl]benzenesulfonato(3 -)][4 -[(5 -chloro-2 -hydroxyphenyl)azo]-2,4 -dihydro-5 -methyl-2 -phenyl-3H-pyrazol-3 -onato(2 -)]-,sodiumis not known and only predicted data is available for the substance, it has been concluded thatchemical Chromate(2 -), [4 -[4 -[(5 -chloro-2 -hydroxyphenyl)azo]-4,5 -dihydro-3 -methyl-5 -oxo-1H-pyrazol-1 -yl]benzenesulfonato(3 -)][4 -[(5 -chloro-2 -hydroxyphenyl)azo]-2,4 -dihydro-5 -methyl-2 -phenyl-3H-pyrazol-3 -onato(2 -)]-,sodiumis likely to be persistent (P) 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 was estimated to be 5.77, which is greater than the threshold of 4.5. If this chemical is released into the aquatic environment, there should be a high risk for the chemical to bioaccumulate in fish and food chains.

 

Thus, based on the logKow value, it indicates thatchemicalN-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amineis likely to be bioaccumulative (B) 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,testing for this end point is considered scientifically unjustified since there are mitigating factors indicating that aquatic toxicity is unlikely to occur as the substance is highly insoluble in water (solubility: 0.00844 mg/L at 25° C). The chemical Chromate(2 -), [4 -[4 -[(5 -chloro-2 -hydroxyphenyl) azo]-4,5 -dihydro-3 -methyl-5 -oxo-1H-pyrazol-1 -yl]benzenesulfonato(3 -)][4 -[(5 -chloro-2 -hydroxyphenyl)azo]-2,4 -dihydro-5 -methyl-2 -phenyl-3H-pyrazol-3 -onato(2 -)]-,sodium 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.