p,p',p''-tris(diethylamino)trityl alcohol

PBT assessment

PBT assessment: overall result

PBT status:

the substance is not PBT / vPvB

Justification:

Classification of p,p',p''-tris(diethylamino)trityl alcohol for effects in the environment:

 

The chemical p,p',p''-tris(diethylamino)trityl alcohol (CAS no. 596-49-6) is used for dyestuff application. The aim was to assess whether the PBT criterion within Annex XIII was fulfilled for p,p',p''-tris(diethylamino)trityl alcohol. 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

Estimation Programs Interface Suite (EPI suite, 2016) was run to predict the biodegradation potential of the test compound Benzenemethanol, 4-(diethylamino)-alpha,alpha-bis(4-(diethylamino)phenyl)- (CAS no. 596-49-6) 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 Benzenemethanol, 4-(diethylamino)-alpha, alpha-bis (4-(diethylamino ) phenyl)- is not expected to be readily biodegradable..

 

Various experimental studies on read across substances (CAS: 129-17-9 and 1694-09-3) 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 soil and sediment (i.e.estimated to 60.8% and 36.7% respetively). In sediment and soil, the substance was expected to have low mobility based upon a Log KOC of 5.80. The half-life in sediment and soil (1620.83 days and 360 days, respectively estimated by EPI suite) indicates that the chemical is persistent the exposure risk to sediment and soil dwelling animals is moderate high.

 

If released in to the environment, 2.5 % of the chemical will partition into water according to the Mackay fugacity model level III in EPI suite version 4.1 (2016). However, the half-life (180 days estimated by EPI suite) indicates that the exposure risk to aquatic animals is moderate.

Hence it has been concluded that p,p',p''-tris(diethylamino)trityl alcohol is persistent in nature.  

 

Although the half-life values reported suggest classification of the substance as very Persistent(vP), it is classified only as Persistent (P) due to lack of experimental data since only estimated values are available.

 

Bioaccumulation assessment

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

 

The estimated log octanol-water partition coefficient (log Kow) was determined to 7.86. 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 VII and 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 (solubility: 0.00425 mg/L). 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.