Registration Dossier

Administrative data

Endpoint:
Henry's law constant
Type of information:
calculation (if not (Q)SAR)
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
Acceptable calculation method using measured physical chemical properties. This study was selected as the key study because the information provided for the hazard endpoint is sufficient for the purpose of classification and labelling and/or risk assessment.

Data source

Reference
Reference Type:
other: REACH Guidance
Title:
Unnamed
Year:
2008

Materials and methods

Principles of method if other than guideline:
Henry's Law constants were calculated for TNS using EQUATION R.16-10 (Henry = (VP*MW)/Solubility) in the REACH guidance R.16.4.3.2. A measured vapour pressure (VP) of 1.07 Pa was used to calculate HLC for all three species. Water-solubility values (Solubility) used in the HCL calculations were 2.4, 0.103, and 0.026 g/L, respectively, for the mono-, bis-, and pyro- species. Molecular weights (MW) used to calculate HLC are those of the dissociated ion (444.09, 790.18, 870.16 g/mol, for the mono-, bis-, and pyro- species, respectively).
GLP compliance:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent

Results and discussion

Henry's Law constant Hopen allclose all
H:
0.2 other: Pa-m3/mole (mono- species)
H:
8.21 other: Pa-m3/mole (bis- species)
H:
35.8 other: Pa-m3/mole (pyro- species)

Any other information on results incl. tables

Calculated Henry Law Constants (HLC) for the mono-, bis-, and pyro- species are 1.948E-006, 8.075E-005, and 3.523E-004 atm-m3/mole, respectively.

Applicant's summary and conclusion

Conclusions:
A Level III fugacity model (EPI SUITE v4.00) indicate the test substance will partition predominately to soil (41 to 54%) and water (45 to 58%) with little partitioning to air (0.61 to 2.0%) and sediment (<1%). The study and the conclusions which are drawn from it fulfill the quality criteria (validity, reliability, repeatability).
Executive summary:

Henry's Law constants were calculated for TNS from measured vapour pressure (8E-003 mm Hg or 1.07 Pa) used for all three species for which HLC was calculated) and solubility values (2.4, 0.103, and 0.026 g/L, for the mono-, bis-, and pyro- species) and molecular weight (444.09, 790.18,870.16 g/mol, for the mono-, bis-, and pyro- species)) using EQUATION R.16-10 (Henry = (VP*MW)/Solubility) in the REACH guidance R.16. Calculated Henry Law Constants (HLC) for the mono-, bis-, and pyro- species are 0.20, 8.21, and 35.8 Pa-m3/mole, respectively. 

A Level III fugacity model (EPI SUITE v4.00) with user entered values for vapour pressure, water solubility, and Kow (-1.37, 0.35, and 0.20, respectively, for the mono-, bis-, and pyro- species) was used to describe the environmental distribution of the mon-. bis-, and pyro- species. The model assumed equal emission to air, water, and soil and used the log Kow-based soil Koc value from KOCWIN. This analysis indicates that the test substance will partition predominately to soil (41 to 54%) and water (45 to 58%) with little partitioning to air (0.61 to 2.0%) and sediment (<1%). One or more of the components are expected to have a high to very high mobility to ground water if emitted to soil.