Heavy metal contamination status in Greek surface waters: A review with application and evaluation of pollution indices

Heavy metal contamination of the aquatic environment is of worldwide concern, due to the toxicity of metals and their lethal effects on aquatic organisms. The investigation of heavy metal concentrations in freshwater bodies has increased over the last decades in Greece; however, most studies have been sporadic and spatially limited. An overall assessment of the heavy metal contamination status in Greek surface water bodies is lacking. In this review, all available published data from 1999 to 2019 were collected and analysed to assess the heavy metal contamination status of the surface water bodies of Greece. Data were available for 68 water bodies and several pollution indices (e.g. Heavy Metal Pollution index, Geoaccumulation index, Moderated Pollution Index) were calculated to evaluate their surface water quality. Overall, heavy metal concentrations in water samples were below the Environmental Quality Standards (EQS) and the vast majority of water bodies were classified as good quality based on surface water pollution indices. Sediment heavy metal concentrations exceeding the Sediment Quality Guidelines (SQGs) were detected in most water bodies. Rivers Axios, Evros, Louros, Gallikos, Greveniotikos, Palea Kavala, Kompsatos, Alfeios and Evrotas, and lakes Pamvotis, Doirani and Koumoundourou were either moderately or highly contaminated. Up to date, heavy metal pollution indices used worldwide for surface waters refer to potable water. Thus, pollution indices must be developed for assessing primarily the ecological consequences of heavy metal pollution and surface water pollution status. Finally, sediment pollution guidelines must be suggested at a European or regional level. [Display omitted] •Heavy metal data from Greek surface water bodies from 1990 to 2019 were collected.•Surface water quality of 68 water bodies based on pollution indices were assessed.•Most water bodies were classified as good based on surface water pollution indices.•Sediments of most water bodies were heavily contaminated mainly by Ni and Cr.•Cd and PI indices were chosen as appropriate for surface water pollution status.