Not all substances have a unique searchable CAS number in EH40 so you have to text search as well e.g. isocyanates have a generic entry. Then there are the "calculated" materials e.g. petroleum distillates - the methodology is listed in the back but ideally your supplier or their suppliers should already have done this. You can also use the online Gestis database which tabulates EU and worldwide values If you want to go more in depth the ECHA website allows substance searching - look at the registration dossier and you will find the newer values of DNEL derived no effect limit and PNEC perceived no effect concentration. Where DNELs are listed they get broken down in to exposure routes and values for workers or the general public All this data should appear on a current well prepared CLP SDS - personally still searching for this mythical beast