Abstract: Method for analyzing adducts in a fluid and/or a solid material suspected of containing the adducts by bringing the material in contact with an isothiocyanate reagent containing a fluorescent. The reagent do not have the isothiocyanate group directly bound to an unsubstituted phenyl or pentafluorophenyl group. A method for manufacturing a standard material for use in the analyzing method, a standard material obtainable by this manufacturing method. Compounds suitable for use as standard material and use of the standard material, and a container for analyzing the adducts are also disclosed. A method for analyzing hazardous substances, a kit including standard material or a compound set out above, an apparatus for performing the analyzing method, and a computer program stored on a data carrier for performing the analyzing method or the manufacturing method are also disclosed.