Bu çal›flmada salt bak›r ile bak›r + kadmiyum kar›fl›m›n›n, farkl› ortam deriflimlerinin etkisinde tatl›su çipuras›n›n (Oreochromis niloticus, L.) solungaç, karaci¤er, böbrek ve kas dokular›ndaki bak›r birikimi üzerine etkilerinin belirlenmesi amaçlanm›flt›r. Deneyler iki seri halinde yürütülmüfl, bal›klar her iki seride de 1, 7, 15 ve 30 gün sürelerle, birinci seride 0,1; 0,5; 1,0 ve 5,0 ppm bak›r, ikinci seride ise 0,1 + 0,05; 0,5 + 0,1; 1,0 + 0,5 ve 5,0 + 1,0 ppm bak›r + kadmiyum ortam deriflimlerinin etkisine b›rak›lm›flt›r. Deneyler süresince, her iki deney serisinde de belirlenen ortam deriflimlerinin etkisinde bal›klarda mortalite gözlenmemifltir. Genel olarak incelenen doku ve organlardaki bak›r birikimi etkide kalma süresi ve ortam deriflimindeki art›fla ba¤l› olarak artm›flt›r. Bak›r + kadmiyum kar›fl›mlar›n›n solungaç, karaci¤er, böbrek ve kas dokular›ndaki bak›r birikim düzeyine etkileri, ortam deriflimine, etkide kalma süresine ve dokulara göre farkl›l›k göstermifltir.

Experiments were conducted in two series for 1, 7, 15 and 30 days. In the first series, fish were exposed to 0.1, 0.5, 1.0 and 5.0 ppm of copper and in the second series to 0.1 + 0.05, 0.5 + 0.1, 1.0 + 0.5 and 5.0 + 1.0 ppm of copper and cadmium mixtures. No mortalities were observed during the experimental period. Accumulation of copper in the tissues and organs increased with increasing concentrations of copper and with longer exposure periods. Copper accumulation associated with copper + cadmium mixtures in the gill, liver, kidney and muscle tissues varied with the concentration, exposure period and tissue type.