Xylene

Henry's Law constant

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

Henry's law constant

Type of information:

calculation (if not (Q)SAR)

Adequacy of study:

key study

Study period:

2008

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: QSAR calculation, acceptable with restrictions

Principles of method if other than guideline:

HENRYWIN estimates the Henry's Law Constant by two different methods, resulting in two separate estimates.  The methods are the Bond Contribution Method and the Group Contribution Method. The Bond Contribution Method estimates the Henry's Law Constant based on the bonds present in the molecule based on a training set of 263 substances. The Group Contribution method estimates the Henry's Law Constant based on groups present in the molecule, based on a training set of 212 substances.

GLP compliance:

no

Specific details on test material used for the study:

SMILES: c(cccc1)(c1)CC

Key result

H:

800 Pa m³/mol

Temp.:

25 °C

Atm. press.:

1 013 hPa

Remarks on result:

other: Bond contribution method

H:

900 Pa m³/mol

Temp.:

25 °C

Atm. press.:

1 013 hPa

Remarks on result:

other: Group Contribution method

N/A

Conclusions:

The calculated Henrys Law Constant is 800-900 Pa m³/mol for ethylbenzene. For the purposes of the environmental risk assessment the lower value will be taken forward.

Executive summary:

The Henry's Law Constant of ethylbenzene has been calculated by two QSAR methods recommended by ECHA (2008) Guidance on information requirements and chemical safety assessment R7a Endpoint specific guidance. The calculated Henrys Law Constant is 800-900 Pa m³/mol for ethylbenzene.

Reference 2

Endpoint:

Henry's law constant

Type of information:

(Q)SAR

Adequacy of study:

key study

Study period:

2017

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Non GLP, QSAR calculation, acceptable with restrictions.

Justification for type of information:

QSAR prediction

Principles of method if other than guideline:

HENRYWIN estimates the Henry's Law Constant of organic compounds at 25°C using the methodology originally described by Hine and Mookerjee (1975) and updated and expanded at Syracuse Research Corporation as described in Meylan and Howard (1991). Subsequent versions include additional fragment and correction factors and an experimental Henry's law constant database of 1829 compounds.

GLP compliance:

not specified

Remarks:

Not applicable

Specific details on test material used for the study:

SMILES: c(cccc1C)(c1)C

Key result

H:

623 Pa m³/mol

Temp.:

25 °C

Remarks on result:

other: Group estimation method

H:

665 Pa m³/mol

Temp.:

25 °C

Remarks on result:

other: Bond estimation method

H:

728 Pa m³/mol

Temp.:

25 °C

Remarks on result:

other: Experimental database

H:

452.2 Pa m³/mol

Temp.:

25 °C

Remarks on result:

other: Calculated using estimated vapour pressure and water solubility values

N/A

Conclusions:

The Henry's Law Constant of m-xylene is 623 Pa.m3/mole.

Executive summary:

The Henry's Law Constant has been taken from a QSAR estimate. The values determined using the group and bond contribution methods are 623 and 665 Pa.m3/mole, respectively. The experimental database and calculations using estimated vapour pressure and water solubility gave values of 728 and 452.2 Pa.m3/mole respectively for m-xylene.

Reference 3

Endpoint:

Henry's law constant

Type of information:

(Q)SAR

Adequacy of study:

key study

Study period:

2017

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Non GLP, QSAR calculation, acceptable with restrictions.

Justification for type of information:

QSAR prediction

Principles of method if other than guideline:

HENRYWIN estimates the Henry's Law Constant of organic compounds at 25°C using the methodology originally described by Hine and Mookerjee (1975) and updated and expanded at Syracuse Research Corporation as described in Meylan and Howard (1991). Subsequent versions include additional fragment and correction factors and an experimental Henry's law constant database of 1829 compounds.

GLP compliance:

not specified

Remarks:

Not applicable

Specific details on test material used for the study:

SMILES: c(c(ccc1)C)(c1)C

Key result

H:

623 Pa m³/mol

Temp.:

25 °C

Remarks on result:

other: Group estimation method

H:

665 Pa m³/mol

Temp.:

25 °C

Remarks on result:

other: Bond estimation method

H:

525 Pa m³/mol

Temp.:

25 °C

Remarks on result:

other: Experimental database

H:

430 Pa m³/mol

Temp.:

25 °C

Remarks on result:

other: Calculated using estimated vapour pressure and water solubility values

N/A

Conclusions:

The Henry's Law Constant of o-xylene is 623 Pa.m3/mole.

Executive summary:

The Henry's Law Constant has been taken from a QSAR estimate. The values determined using the group and bond contribution methods are 623 and 665 Pa.m3/mole, respectively. The experimental database and calculations using estimated vapour pressure and water solubility gave values of 525 and 430 Pa.m3/mole respectively for o-xylene.

Reference 4

Endpoint:

Henry's law constant

Type of information:

(Q)SAR

Adequacy of study:

key study

Study period:

2017

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Non GLP, QSAR calculation, acceptable with restrictions.

Justification for type of information:

QSAR prediction

Principles of method if other than guideline:

HENRYWIN estimates the Henry's Law Constant of organic compounds at 25°C using the methodology originally described by Hine and Mookerjee (1975) and updated and expanded at Syracuse Research Corporation as described in Meylan and Howard (1991). Subsequent versions include additional fragment and correction factors and an experimental Henry's law constant database of 1829 compounds.

GLP compliance:

not specified

Remarks:

Not applicable

Specific details on test material used for the study:

SMILES: c(ccc(c1)C)(c1)C

Key result

H:

623 Pa m³/mol

Temp.:

25 °C

Remarks on result:

other: Group estimation method

H:

665 Pa m³/mol

Temp.:

25 °C

Remarks on result:

other: Bond estimation method

H:

699 Pa m³/mol

Temp.:

25 °C

Remarks on result:

other: Experimental database

H:

425 Pa m³/mol

Temp.:

25 °C

Remarks on result:

other: Calculated using estimated vapour pressure and water solubility values

N/A

Conclusions:

The Henry's Law Constant of p-xylene is 623 Pa.m3/mole.

Executive summary:

The Henry's Law Constant has been taken from a QSAR estimate. The values determined using the group and bond contribution methods are 623 and 665 Pa.m3/mole, respectively. The experimental database and calculations using estimated vapour pressure and water solubility gave values of 699 and 425 Pa.m3/mole respectively for p-xylene.

Reference 5

Endpoint:

Henry's law constant

Type of information:

(Q)SAR

Adequacy of study:

key study

Study period:

2017

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Non GLP, QSAR calculation, acceptable with restrictions.

Justification for type of information:

Episuite and the HenryWin models are well documented and commonly used QSARs for predicting the biodegradation potential of chemicals. Substances within LOA fall within the applicability domain of these models and they have been recommended by ECHA in the Information Requirement Guidelines.

Principles of method if other than guideline:

HENRYWIN estimates the Henry's Law Constant of organic compounds at 25°C using the methodology originally described by Hine and Mookerjee (1975) and updated and expanded at Syracuse Research Corporation as described in Meylan and Howard (1991). Subsequent versions include additional fragment and correction factors and an experimental Henry's law constant database of 1829 compounds.

GLP compliance:

not specified

Remarks:

Not applicable

Specific details on test material used for the study:

SMILES: Cc1ccccc1C

Key result

H:

623 Pa m³/mol

Temp.:

25 °C

Remarks on result:

other: Group estimation method

H:

665 Pa m³/mol

Temp.:

25 °C

Remarks on result:

other: Bond estimation method

H:

430.1 Pa m³/mol

Temp.:

25 °C

Remarks on result:

other: Calculated using estimated vapour pressure and water solubility values

N/A

Conclusions:

The Henry's Law Constant of m-xylene is 623 Pa.m3/mole.

Executive summary:

The Henry's Law Constant has been taken from a QSAR estimate. The values determined using the group and bond contribution methods are 623 and 665 Pa.m3/mole, respectively. The calculations using estimated vapour pressure and water solubility gave a value of 430.1 Pa.m3/mole for xylene.

Description of key information

The Henry's Law Constant for the xylene isomers is 623 Pa.m3/mol. The calculated Henrys Law Constant for ethylbenzene was 800 Pa.m3/mol. The lowest value calculated via the group and bond contribution methods were used as the key value.

Key value for chemical safety assessment

Henry's law constant (H) (in Pa m³/mol):

623

at the temperature of:

25 °C

Additional information

The Henry's Law Constant has been taken from QSAR estimates following the group and bond contribution methods. Also reported are the individual values for the isomers from the experimental database and calculations using estimated vapour pressure and water solubility. These results are supported by data from the CRC Handbook (Lide 2008).