Ž . The Science of the Total Environment 237238 1999 387400 Survey of metal levels in common fish species from Greek waters Vassiliki-Angelique Catsiki  , Evangelia Strogyloudi National Centre for Marine Research, A. Kosmas, Hellinikon, Athens 16604, Greece Abstract This survey provided information for the background levels of metals in two common fish species of the Hellenic Seas. The concentration of Cu, Cr, Ni, Zn, Fe and Mn was monitored during the period 1987 1997 in the gills and Ž . Ž . flesh of the demersal Mullus barbatus striped mullet and the pelagic Boops boops bogue collected from a network of six sampling sites covering the Aegean and Ionian Seas. The effectiveness of the above fish as biomonitors for temporal evolution studies is also investigated. The results of more than 3400 analyses showed that the temporal evolution of each metal presented similar patterns in all the sampling stations. Copper, Ni and Zn seemed to increase with time, while Cr and Fe seemed to decrease. However, the metals were not evenly distributed in the fish of the Greek seas. The differences between the sampling stations could not be explained by known differences in the quality of the marine environment. Our results suggest that the fish species used, as well as the fish tissues selected, were good metal pollution indicators since similar temporal evolution patterns were obtained when using mindless Ž . Ž . the gills or the flesh of demersal M. barbatus or pelagic B. boops fish. Finally the determined levels in the studied fish from the Greek seas were low and similar to those from other non-polluted Mediterranean areas.  1999 Elsevier Science B.V. All rights reserved. Keywords: Metals; Monitoring; Greece; Bio-indicator; Mullus barbatus; Boops boops 1. Introduction Metal pollution of the sea is less visible and direct than other types of marine pollution but its  Corresponding author. Tel.: 30-1-9653521; fax: 30-1- 9653522. Ž . E-mail address: cats@erato.fl.ncmr.gr V. Catsiki effects on marine ecosystems and humans are intensive and very extensive. As an indirect mea- sure of the abundance and availability of metals in the marine environment the bioaccumulation of metals by the tissues of marine organisms is studied. The bioaccumulation studies led to the Ž adoption of the bio-indicator concept Langston . and Spence, 1995 . Fish are widely used as bio-indicators of marine 0048-969799$ - see front matter  1999 Elsevier Science B.V. All rights reserved. Ž . PII: S 0 0 4 8 - 9 6 9 7 99 00152-7