Sodium salts of [[(phosphonomethyl)imino]bis[ethane-2,1-diylnitrilobis(methylene)]]tetrakisphosphonic acid (5-7:1)

Vapour pressure

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

vapour pressure

Type of information:

(Q)SAR

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

Please refer to attached justification documents

Principles of method if other than guideline:

Estimation by MPBPVP program, USEPA/Syracuse Research, v1.40

Key result

Test no.:

#1

Temp.:

25 °C

Vapour pressure:

0 Pa

Conclusions:

A vapour pressure value of 2.7E-09 Pa was obtained by valid read-across. The result is considered to be reliable.

Reference 2

Endpoint:

vapour pressure

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

Vapour pressure data for the acid is read-across to the salt due structural similarity. The salts are produced from the parent acid; diethylene triamine penta(methylene phosphonic acid). The read-across is therefore based on the presence of common functional groups in both the acid and the salt . The impurity profile of the salt is expected to be similar to that of the parent acid since the salt is prepared from the acid.

Reason / purpose:

read-across source

Key result

Test no.:

#1

Temp.:

25 °C

Vapour pressure:

0 Pa

Description of key information

Vapour pressure: < 2.7E-09 Pa at 25°C (QSAR)

Key value for chemical safety assessment

Vapour pressure:

0 Pa

at the temperature of:

25 °C

Additional information

The vapour pressure of the sodium salts of DTPMP has been read across from the parent acid, DTPMP-H. A limit vapour pressure value of 2.7E-09 Pa at 25°C was obtained using accepted calculation method (MPBPVP program, USEPA/Syracuse Research, v1.43). The result (Fisk 2010) is considered to be reliable as a key study. This value represents the major constituent only and demonstrates that it is involatile.

 

The vapour pressure of the salts would be expected to be lower than for the parent DTPMP acid form, hence the result is reported as <2.7E-09 Pa at 25°C.