Toxicity and accumulation of heavy metal in water, sediment, some macro invertebrates in Umurbey stream and Umurbey reservoir (Çanakkale)

This study was conducted to determine physico-chemical parameters of water and sediment and metal accumulation (Pb, Zn, Cd, Fe, Cu and Mn) in water, sediment, some macro invertebrates and also the lethal concentration value of lead on the amphipod (Gammarus aequicauda, Martynov, 1931) living as dominant forms in Umurbey Stream estuary area, and lead accumulation in the crab (Carcinus aestuarii, Nardo, 1847) tissues (gill, muscle, hepatopancreas) were used toxicity tests in laboratory in Umurbey Stream and Umurbey Reservoir in Çanakkale between February 2010 and April 2011 seasonally.For these aims, in the determined 5 stations in Umurbey Stream and Umurbey Reservoir, while water temperature, salinity, dissolved oxygen, electrical conductivity and pH were measured in situ, the sediment pH, conductivity, organic matter, lime, % moisture and texture were measured in laboratory. Besides, samples that were taken from 5 stations and their heavy metal concentrations were analyzied by ICP-OES. For comparing the treatments, one-way and two-way analysis of variance were used (p<0,05). For acute toxicity test, amphipod G. aequicauda were exposed to various lead concentrations (1, 2, 3, 4, 5 and 6 mg L-1) for 96 hours and it was calculated using probit analysis method. Also, C. aestuarii sampled from the eustary area exposed to different concentrations of lead (0.025, 0.05, 0.1 and 1.0 mg L-1) for 14 days and the accumulation of lead in tissues in 7th. and 14th. days were determined by time and concentrations. For statistical analysis the results, three-way analysis of variance was used (p<0,05).The results have revealed that metal concentrations in water were exceeded the threshold level imposed by EPA (2006), while metal concentrations in water were not exceeded the threshold level imposed by SKKY (1991) for irrigation water. In addition, metal concentrations in sediment were not exceeded the threshold level imposed by TGK (2010) except for zinc. While the highest accumulated metal ions were iron and zinc, the least accumulated metal was cadmium in water, sediment and macro invertebrates in Umurbey Stream and Umurbey Reservoir. The MDS (multi-dimensional scaling) results indicated that the metals interact with the other environmental variables.At the end of acute toxicity test, LC50 value of lead for G. aequicauda calculated as 4.56 mg L-1. It was determined that this toxicity test result have just no risk for this species living the area. Besides, it was found out that lead bioaccumulation in tissues of C. aestuarii exposed to different concentrations of lead for 14 days was increased with lead concentration of ambient and time of exposure, the most accumulation was determined in gill tissue.