2-chlorotoluene

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Published 1989 / 1995

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Qualifier:

equivalent or similar to guideline

Guideline:

EPA OPPTS 830.7560 (Partition Coefficient, n-octanol / H2O, Generator Column Method)

Version / remarks:

or flask-method performed

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 107 (Partition Coefficient (n-octanol / water), Shake Flask Method)

Version / remarks:

or generator column method performed

Principles of method if other than guideline:

According to Sangster (1989), a direct method of determination was applied, i.e. either the Shake-falsk method (OECD TG 107) or the Generator column method (US EPA OPPTS 830.7560) to derive the preferred selected value.

GLP compliance:

not specified

Other quality assurance:

other: A critical review of available values was performed considering the original literature. Based on this, a recommended value was selected for each compound assessed and correspondingly, an associated uncertainty (+/- x) is specified.

Type of method:

other: either flask method or generator column method was performed to derive the preferred value

Partition coefficient type:

octanol-water

Analytical method:

not specified

Key result

Type:

log Pow

Partition coefficient:

3.42

Remarks on result:

other: +/- 0.20 (uncertainty); temperature not reported (ambient temperature); pH not relevant (non-ionisable)

All details as given according to Sangster (1989) are available in the illustration attached to this IUCLID endpoint study record.

The value selected by Sangster (preferred value) originates from the Pomona College log P Database created and maintained by Prof. Hansch and Leo. It is also published by Hansch et al. (1995), and the reference given is "Tichy,M & Bocek,K., Private Communication" (R531).

Conclusions:

Partition coefficient n-octanol / water (log-value; Shake-flask method or Generator column method): 3.42 (+/- 0.2)

Executive summary:

According to Sangster (1989) and Hansch et al. (1995), the partition coefficient n-octanol / water (log Pow) for 2-chlorotoluene was determined to be 3.42 (+/- 0.2). The value (selected by Sangster as the preferred value) originates from the Pomona College log P Database (created and maintained by Prof. Hansch and Leo). It is also published by Hansch et al. (1995) as the preferred value for 2-chlorotoluene, and the reference given is "Tichy,M & Bocek,K., Private Communication". While the exact experimental method is not recorded, according to Sangster (1989) a direct method of determination was applied, i.e., either the Shake-flask method (OECD TG 107) or the Generator column method (US EPA OPPTS 830.7560) was used. Further values given by Sangster (1989) of very similar size but determined via indirect method (estimation by HPLC and reference chemicals) corroborate the selected value.
Accordingly, the log Pow of 3.42 (+/- 0.2) is associated with high confidence.

Description of key information

Partition coefficient n-octanol / water (log-value; Shake-flask method or Generator column method): 3.42 (+/- 0.2)

Key value for chemical safety assessment

Log Kow (Log Pow):

3.42

at the temperature of:

25 °C

Additional information

According to Sangster (1989) and Hansch et al. (1995), the partition coefficient n-octanol / water (log Pow) for 2-chlorotoluene was determined to be 3.42 (+/- 0.2). The value (selected by Sangster as the preferred value) originates from the Pomona College log P Database (created and maintained by Prof. Hansch and Leo). It is also published by Hansch et al. (1995) as the preferred value for 2-chlorotoluene, and the reference given is "Tichy,M & Bocek,K., Private Communication". While the exact experimental method is not recorded, according to Sangster (1989) a direct method of determination was applied, i.e., either the Shake-flask method (OECD TG 107) or the Generator column method (US EPA OPPTS 830.7560) was used. Further values given by Sangster (1989) of very similar size but determined via indirect method (estimation by HPLC and reference chemicals) corroborate the selected value.
Accordingly, the log Pow of 3.42 (+/- 0.2) is associated with high confidence.

A supporting QSAR study corroborates this value (Currenta, 2013):
QSAR estimation was performed with a scientifically validated and reliable model. The substance falls within the applicability domain of the model, results are adequate for risk assessment and the applied method is adequate and reliably documented. The QSAR determination of the logarithmic octanol-water partition coefficient for 2-chlorotoluene using the model KOWWIN included in the Estimation Program Interface (EPI) Suite v4.1 revealed a value of 3.19 for the substance.