Within the MONITOOL project, after exploring the relationships between dissolved and labile metal concentrations, a methodology has been proposed for the adaptation of EQS marine water to DGTs, for cadmium, nickel and lead by establing linear model and previous WP6 deliverable. This was accomplished by using a robust database of total dissolved and DGT-labile metal concentrations obtained by concurrent sampling (i.e., spot sampling and DGT) in transitional and coastal waters of the eight European countries participating in the MONITOOL project (EAPA 565/2016).

As part of the MONITOOL extension (2021-2023), an additionnal sampling campaign was done (2022) at sites known or suspected to be higly contaminated (in coastal area, estuary and closed bassin) in order to complete the dataset in high concentrations with data close to or even above the EQS _{marine water} values. The objective was to increase the range of validity of the original models to include higher concentrations levels (near/above the EQS _{marine water}). In case the 2022 data doesn’t improve the model, they can be used as “additionnal data” to check the fitness of the original MONITOOL models.