One particular type of environmental pollution that affects aquatic environments is constituted by trace elements or heavy metals. The main goal of this investigation was to examine the heavy metal pattern distribution in juvenile fish individuals inhabiting the Hungarian side of the Szamos River. As the results concerning the statistical analyses showed, it could be pointed out that there were no significant differences between the three juvenile species. However, the analyses within the species concluded that the metal concentrations in muscle, gills and liver showed significant differences. One important factor that explained some of the differences of concentrations measured in each of the three species was the distinct feeding habits. This present study calls attention to the source of the pollution in the Szamos River as not just an environmental issue, the impact of the industrial and mining activities on Szamos River is an International Relations case.