6-chlorohexan-2-one

PBT assessment

PBT assessment: overall result

PBT status:

the substance is not PBT / vPvB

Justification:

Classification of 6-chlorohexan-2-one for effects in the environment:

 

6-chlorohexan-2-one (CAS no. 10226-30-9) is used in the pharmaceutical industry. The aim of the PBT assessment was to evaluate whether this chemical fulfils the PBT criterion within Annex XIII. The PBT assessment were based on toxicological information in conjunction with standardized environmental fate- and bioaccumulation 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

Biodegradation in water ability was predicted for the test substance 6-chlorohexan-2-one (CAS no. 10226-30-9) using the OECD QSAR prediction model (Version 3.3, 2016). The ready biodegradability of the test substance 6-chlorohexan-2-one was estimated as 35.659% in 3 days by using O2 consumption parameter. This result indicates that 6 -chlorohexane-2-one was estimated to be readily biodegradable in water.

 

Environmental fate

According to the fugacity model levels III, the most likely environmental fate for this test chemical is soil (i.e.estimated to 64%). The Koc-value was estimated to 27.3 at 25ºC (KOCWIN program) indicating very high mobility and negligible adsorption potential.

The tested chemical is therefore expected to leach from soil. The half-life in soil (75 days estimated by EPI suite) indicates that the exposure risk to soil-dwelling organism should therefore be low.

 

If released in to the environment, 34.2 % 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 (37.5 days estimated by EPI suite) indicates that 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% when estimated by EPI Suite version 4.1). Hence it has been concluded that 6-chlorohexan-2-one 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:

 

The BCF value is estimated to be 4.484 L/kg (calculated by EPI suite version 4.1, 2016) and the Kow value is approx. 1.4923 at 25ºC (EPI suite version 4.1, 2016). 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

Most of the available short-term eco-toxicity estimation for fish, invertebrates and algae for the substance indicates the LC50/EC50 value are above 100 mg/L indicating that the substance is classified as non-hazardous as per the CLP criteria. Some values indicate the classification in Chronic category 3 but since the substance is readily biodegradable, it was not classified as hazardous as per the CLP criteria.These values suggest classification for aquatic toxicity will not be applicable for all of the tropic levels.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 does not fulfil the P, B and T criterion and has therefore not been classified as a PBT compound within Annex XIII.