Assessing pollution levels and health effects of heavy metals in sediments around Cayeli copper mine area, Rize, Turkey

Heavy metal concentrations of Mn, Cr, Fe, Ni, Cu, Zn, Cd and Pb in sediment samples collected from 12 stations in the Black Sea coast, Buyukdere and Sabuncular streams around Cayeli copper mine area in Rize, Turkey were measured using Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES). The mean concentrations of Mn, Cr, Fe, Ni, Cu, Zn, Cd and Pb in the sediments have been determined to be 585.10, 22.50, 33,603.95, 7.40, 63.97, 75.50, 0.20 and 7.83, respectively. The mean heavy metal concentrations examined in sediment samples have been determined as lower than the permissible level for sediment. Assessment of the heavy metals pollution in the sediments was carried out by calculating the enrichment factor (EF), geoaccumulation index (I-geo), contamination factor (CF) and pollution load index (PLI) indices. It has been found according to the mean EF values in sediment samples that Mn, Cr, Fe, Ni and Pb had no enrichment while Cu, Zn and Cd showed minor enrichment in the field. The mean I-geo and PLI values indicated that sediments in the field were not polluted with all heavy metals examined. PCA showed that the origin of Mn, Cr, Ni and Pb was natural sources and Cu, Zn and Cd were lowly influenced from anthropogenic inputs, and the origin of Fe was also natural sources but was slightly influenced from anthropogenic inputs. Human health risk assessment of the heavy metals was carried out by calculating the hazard quotient (HQ) and the hazard index (HI) for the non-carcinogenic metals and the carcinogenic risk (CR) for the carcinogenic metals through ingestion and dermal contact. The mean HQ, HI and CR values were in safety limits. This indicated that the levels of all heavy metals examined in the sediments did not cause carcinogenic and non-carcinogenic health risks for humans via ingestion and dermal contact.