Comparative investigation of heavy metal concentration in water, sediment and Corixa affinis Leach, 1817 (Heteroptera; Corixidae) of Karacomak River (Kastamonu)

In this study, 8 stations from Karaçomak River were chosen and water, sediment and insects samples (Corixa affinis Leach, 1817 (Heteroptera; Corixidae)) were taken to determine the seasonal heavy metal accumulation. Samples were taken with appropriate analytical techniques and Pb, Cr, Ni, Zn, Mn and Cu concentrations were determined by using ICP-OES device. Sources of heavy metals pollution in Karaçomak River were determined as sewage, industrial effluent, fertilizers, herbicide and pesticide. It was observed that the metal concentration means per annum were in the water Mn> Cu> Zn> Pb> Ni> Cr. Seasonal highest values of heavy metals were observed as follows; Pb (14.018 µg/L) and Ni (2.469 µg/L) in summer, Cr (2.079 µg/L), Zn (20.789 µg/L), Mn (58.296 µg/L) and Cu (19.072 µg/L) in winter. In general, the values of heavy metals in the water recorded in this study did not exceed permissible limits for international standards of drinking water According to the reference values except lead metal that exceeded Permissible limits. It was observed that the mean sequence of the metal concentration per annum in the sediment were Mn> Cu> Zn> Ni> Pb> Cr. Seasonal highest values of heavy metals were observed as follows; Pb (0.389 µg/g) and Ni (0.646 µg/g) in summer, Cr (0.276 µg/g), Zn (0.921 µg/g), Mn (13.052µg/g) and Cu (1.818 µg/g) in winter. According to the reference values, Pb, Cr, Ni, Zn, Mn and Cu contaminations in the river sediment have not reached the effective level. The results also showed a biological accumulation of heavy metals in insect for each of Corixa affinis Leach, 1817 (Heteroptera; Corixidae). Where heavy metal concentrations in the insects were decreased in sequence of Zn>Cu>Mn>Pb>Cr>Ni. Findings in this study in Karaçomak river, basis for subsequent pollution studies and pollution studies should be continued as periodic.