This part of ISO 23893 specifies a method for measuring vitellogenin (Vtg) concentrations in a fish plasma sample employing an enzyme-linked immunosorbent assay (ELISA) method.

It applies to fish that are sampled in the environment (fresh, estuarine or salt water) and to fish exposed to substances or effluents in a laboratory. The method is quantitative when using Vtg antibodies and a Vtg standard well characterized with the species of choice.