2. How to establish an OEL?

2.1 Establishment of OELs

The establishment of OELs is an important step in the overall process of assessing the hazards of a chemical substance. It is the logical continuation of studies that have been carried out to determine the ADME of this substance, as well as the results of short-, medium-, and long-term in vitro and in vivo toxicological studies.

First, the toxicological profile of the substance must be established and all relevant data collected, then the most relevant and valid studies must be selected (Klimisch).

Relevant physicochemical data must be collected by inhalation, in particular the form (gas or particles), particle size, volatility of the liquid (boiling point and vapor pressure – PKa), solubility in aqueous and...