Denatonium benzoate

PBT assessment

PBT assessment: overall result

Reference

Name:

disodium 5-acetylamino-4-hydroxy-3-(phenylazo)naphthalene-2,7-disulphonate

Type of composition:

boundary composition of the substance

State / form:

solid: particulate/powder

Reference substance:

disodium 5-acetylamino-4-hydroxy-3-(phenylazo)naphthalene-2,7-disulphonate

PBT status:

the substance is not PBT / vPvB

Justification:

Classification of N-benzyl-2-[(2,6-dimethylphenyl)amino]-N,N-diethyl-2-oxoethanaminium benzoate hydrate for effects in the environment:

 

The chemical N-benzyl-2-[(2,6-dimethylphenyl)amino]-N,N-diethyl-2-oxoethanaminium benzoate hydrate (CAS no. 3734-33-6) is used as an oral deterrent, alcohol denaturant and flavor in pharmaceuticals. It is also used in antifreeze, nail biting preventions, respirator mask fit-testing, animal repellents, liquid soaps and shampoos. Further, it is used in air care products. In addition to this, it is used as a disinfectant.The aim was to assess whether the PBT criterion within Annex XIII was fulfilled forN-benzyl-2-[(2,6-dimethylphenyl)amino]-N,N-diethyl-2-oxoethanaminium benzoate hydrate. 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

28-days Manometric respirometry test following the OECD guideline 301F to determine the ready biodegradability of the test itemN-benzyl-2-[(2,6-dimethylphenyl)amino]-N,N-diethyl-2-oxoethanaminium benzoate hydrate(Denatonium benzoate) (CAS No. 3734-33-6) was conducted. The test system included control, test item and reference item. The concentration of test and reference item (Sodium Benzoate) chosen for both the study was 100mg/L, while that of inoculum was 10ml/l. ThOD (Theoretical oxygen demand) of test and reference item was determined by calculation. % Degradation was calculated using the values of BOD and ThOD for test item and reference item. The BOD28value of Denatonium benzoate (CAS No. 3734-33-6) was observed to be 0.436 mgO2/mg. ThOD was calculated as 2.40mgO2/mg. Accordingly, the % degradation of the test item after 28 days of incubation at 20 ± 1°C according to manometric respirometry test was determined to be 18.17%. Based on the results, the test item, under the test conditions, was considered to be not readily biodegradable at 20 ± 1°C over a period of 28 days.

 

Bioaccumulation assessment

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

 

Theoctanol water partition coefficient of the test chemical ranges from 2.2 to 2.062 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 in the range > 100– > 1000 mg/L. These value suggest that the substance is not likely to be 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 forN-benzyl-2-[(2,6-dimethylphenyl)amino]-N,N-diethyl-2-oxoethanaminium benzoate hydrate. 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 fulfils 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.