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Description of key information

Adsorption/desorption:

The adsorption coefficient Koc in soil and in sewage sludge of test chemical (2R,5S)-5-methyl-2-(propan-2-yl)cyclohexan-1-one (CAS no. 89-80-5)was determined by the Reverse Phase High Performance Liquid Chromatographic method according to OECD Guideline No. 121 . The reference substances were chosen according to functional similarity with the test substance and calibration graph prepared.

The reference substances were Benzamide, Nitrobenzene, 4- Nitrobenzamide, N,N-dimethylbenzamide, N-methylbenzamide, 2 - nitrophenol having Koc value ranging from 1.239 to 2.47. The Log Koc value was determined to be 1.805 dimensionless at 25°C.

Thus based on the result it is concluded that the test substance (2R,5S)-5-methyl-2-(propan-2-yl)cyclohexan-1-one has a low sorption to soil and sediment and therefore has moderate migration potential to ground water.

Additional information

Adsorption/desorption:

Experimental study and predicted data for the target compound (2R,5S)-5-methyl-2-(propan-2-yl)cyclohexan-1-one (CAS No. 89-80-5) and varioussupporting studiesfor its structurally similar read across substance were reviewed for the adsorption end point which are summarized as below:

In first experimental study the adsorption coefficient Koc in soil and in sewage sludge of test chemical (2R,5S)-5-methyl-2-(propan-2-yl)cyclohexan-1-one (CAS no. 89-80-5)was determined by the Reverse Phase High Performance Liquid Chromatographic method according to OECD Guideline No. 121 . The reference substances were chosen according to functional similarity with the test substance and calibration graph prepared.

The reference substances were Benzamide, Nitrobenzene, 4- Nitrobenzamide, N,N-dimethylbenzamide, N-methylbenzamide, 2 - nitrophenol having Koc value ranging from 1.239 to 2.47. The Log Koc value was determined to be 1.805 dimensionless at 25°C.

Thus based on the result it is concluded that the test substance (2R,5S)-5-methyl-2-(propan-2-yl)cyclohexan-1-one has a low sorption to soil and sediment and therefore has moderate migration potential to ground water.

In next experimental study the Adsorption experiment was conducted for estimating the adsorption coefficient (Koc) value of test chemical (2R,5S)-5-methyl-2-(propan-2-yl)cyclohexan-1-one (CAS no. 89-80-5). The adsorption coefficient (Koc) value was calculated using a water solubility of 688 mg/l and regression derived equation. The adsorption coefficient (Koc) value of test substance (2R,5S)-5 -methyl-2 -(propan-2 -yl)cyclohexan-1 -one was estimated to be 120 (Log Koc = 2.079). This Koc value indicates that the substance (2R,5S)-5 -methyl-2 -(propan-2 -yl)cyclohexan-1 -one has a low sorption to soil and sediment and therefore have moderate migration potential to ground water.

Further another adsorption study was conducted for estimating the adsorption coefficient (Koc) value of test chemical. The adsorption coefficient (Koc) value was calculated using a structure estimation method based on molecular connectivity indices. The adsorption coefficient (Koc) value of test substance was estimated to be 88 dimensionless (Log Koc = 1.944). This Koc value indicates that the substance has a low sorption to soil and sediment and therefore have moderate migration potential to ground water.

On the basis of above overall results for target chemical (2R,5S)-5-methyl-2-(propan-2-yl)cyclohexan-1-one(from authoritative database HSDB, PubChem, EPI suite and ACD labs,2017) and for its read across substance (from authoritative database HSDB, 2017), it can be concluded that the Koc value of test substance (2R,5S)-5-methyl-2-(propan-2-yl)cyclohexan-1-one ranges from 120–638 indicating that the test chemical (2R,5S)-5-methyl-2-(propan-2-yl)cyclohexan-1-one has a low sorption to soil and sediment and therefore have moderate migration potential to ground water.