In this study, the geographic distribution of toxic element concentrations was determined in
Northeast Marmara Sea (Istanbul/Turkey) sediments. In addition, the pollution degree of the environment
was analyzed using various pollution index methods. Geochemical analysis of 28 elements were
performed in sediment samples. The concentrations of several elements (especially Fe, Mn, Ti, Zn, and
Cr) were found to be very high in some locations. At sites, where heavy metal concentrations were high,
foraminifera genera and species numbers and number of individuals were very low. The low number of
foraminifera in the samples taken from some regions could be due to uncontrolled ship traffic and
domestic and industrial discharges.