Fatty acids, C16-18, lead salts

Vapour pressure

Administrative data

Endpoint:

vapour pressure

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Justification for type of information:

JUSTIFICATION FOR DATA WAIVING

The vapour pressure of a substance is defined as the saturation pressure above a solid or liquid substance. Several different measuring methods are listed for the measurement of the vapour pressure of solids and liquids. However, the vapour pressure does not need to be measured due to technical reasons if calculations indicate that the value is significantly less than 10-5 Pa.

Neutral lead stearate is a solid inorganic substance with a melting point at 101 - 105 °C. In view of this, the volatility of this substance can therefore be safely assumed to be negligible, i.e. below the level of significance (10-5 Pa).

For purposes of comparison, QSAR (MPBPVP, version 1.43) calculation of the vapour pressure of the organic acid moiety was performed, yielding a vapour pressure of 0.00111 Pa (8.31 * 10-6 mmHg) at 25°C (modified Grain method) for stearic acid. The experimental values from this EPISUITE (v4.11) database are given as 89.63 * 10-5 Pa (7.22 * 10-7 mmHg). In consideration of the “salt” nature of this compound, it can therefore be anticipated that the vapour pressure of the fatty acids, C16-C18, lead salts is well below the value for the organic acid, and thus negligible.

In accordance with Section 1 of REACH Annex XI, the study does not need to be conducted.