In order to evaluate the capacity of mussels to accumulate pollutants and to enhance growth and physiological effects, an investigation was carried out in the Faroe Islands and in the Skagerrak. In March 2000, about 1500 mussels of proper dimensions (length ranging between 5 and 6 cm) were collected in the Kaldbak Fjord (Faroe Islands) on a 10m water column. Selected mussels were divided in 4 groups (320 each) and deployed in 4 different stations (one at the Faroe Islands and three in the Skagerrak). Semipermeable membrane devices (SPMDs) were also deployed in the same stations for the preconcentration of lipophilic pollutants. One month later (end of April-beginning of May) mussels and SPMDs were recollected and sent to different laboratories for the determination of various parameters.