Heavy metals in aquatic systems can be naturally produced by leaching from soil/rock to water, which usually produces low levels, causing no serious deleterious effects on human health (
10.However, the pollution of marine environments is mainly dueto the development of human activities that result in direct or indirect chemical release into the aquatic environment. In particular, it depends on the contaminant loads carried into the sea by rivers and other watercourse basins, which drain areas of intense urbanization, and on the direct input of municipal and industrial waste (11)