2,2,2-trichloroethane-1,1-diol

PBT assessment

PBT assessment: overall result

PBT status:

the substance is not PBT / vPvB

Justification:

Classification of 2,2,2-Trichloroethane-1,1-diol for effects in the environment:

 

The chemical 2,2,2-Trichloroethane-1,1-diol (CAS no. 302-17-0) is usedas drug (sedative and hypnotic), a rubefacient and liniment, a glue peptizing agent etc. It is used as pesticides, pharmaceutical and chemical intermediates. Also used for the manufacture of DDT. The aim was to assess whether the PBT criterion within Annex XIII was fulfilled for2,2,2-Trichloroethane-1,1-diol. 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 does not fulfil 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 item 2, 2, 2 -trichloroethane-1, 1 -diol (CAS No. 302 -17 -0) was conducted. The test system included control, test item and reference item. The concentration of test and reference item (Sodium Benzoate) chosen for the study was 100 mg/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 2,2,2 -trichloroethane-1, 1 –diol (CAS No. 302 -17 -0) was observed to be 0.085 mgO2/mg. ThOD was calculated as 0.193 mgO2/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 44.04%. Based on the results, the test item, under the test conditions, was found to be inherently biodegradable at 20 ± 1°C over a period of 28 days.

 

Thus, based on the above available information, it has been concluded2,2,2-Trichloroethane-1,1-diolis likely to be not persistent in nature.

 

Environmental fate

According to the fugacity model levels III, the most likely environmental fate for this test chemical is soil (i.e.estimated to 54.8%). In soil,2,2,2-Trichloroethane-1,1-diolwas expected to have moderate mobility based upon a Log KOC value 1.645 ± 0.003 at 25°C, respectively. The half-life in soil (75 days estimated by EPI suite) indicates that the chemical is not persistent in soil and the exposure risk to soil dwelling animals is moderate to low.

 

If released in to the environment, 45% 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 (37.5 days estimated by EPI suite) indicates that the chemical is not persistent in water and the exposure risk to aquatic animals is moderate to low.

 

Moreover, its persistent characteristic is only observed in the sediment compartment but Fugacity modelling shows that sediment is not an important environmental fate (less than 1% i.e. reported as 0.0885% when estimated by EPI Suite version 4.1).

 

Hence it has been concluded that 2,2,2-Trichloroethane-1,1-diol 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 3.162 L/Kg, respectivelyand theoctanol water partition coefficient of the test chemical was determined to be ranges from 0.99 to 1.092, respectively, 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 65– 575.918 mg/L, respectively and the long term NOEC value for aquatic invertebrates was determined to be 11.5 mg/l, respectively.

 

Thus, the 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 chemical2,2,2-Trichloroethane-1,1-diolwas 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 does not fulfil the P, B and T criterion and has therefore not been classified as a PBT compound within Annex XIII.