Heavy metals accumulation in coastal sediments

Abstract

Heavy metals, such as arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb), mercury (Hg) and zinc (Zn), are major environmental problem due to their toxic nature, nonbiodegradability and accumulative behaviors. Once in the estuarine/coastal and marine environments, sources predominantly form industrial, agricultural and hydrocarbon-related activities, scrap metal recycling, commercial ports and sewage, these contaminants accumulate in sediments and soils. Thus, heavy metals concentrations in coastal areas around shipyards, ports and industrial sites with refineries, smelters and milling facilities are often far exceed their background values or standard limits that can be toxic. The toxicity of heavy metals may negatively affects marine biodiversity as higher concentration is detected in fish and other organisms. Due to their persistence, through bioaccumulation and biomagnification along the aquatic food chain, heavy metals contamination ultimately affects human health. Here, the sources and impacts of heavy metals pollution in living systems are discussed.