Heavy Metals in Sediments and Fish in the Caribbean Coast of Colombia: Assessing the Environmental Risk

Abstract

Heavy metals have accumulated in fish and marine sediments, especially near large cities or ports. To monitor heavy metal contamination along the Caribbean coast of Colombia, we analyzed sediments and fish by atomic absorption spectrometry to establish a baseline. Fish species were Brown chub (Kyphosus Sp.), Almaco jack (Seriola rivoliana) Grey snapper (Lutjanus cf. griseus), Mullet (Mugil incilis), and catfish (Cathorops mapale, Bagre marinus). Samples were lyophilized and microwave digested. Metal concentrations in fish dorsal muscle (dry weight) were ND-5.3 (Cd), ND-500 (Ni), 10–110 (Pb) and 330–3900 μg/kg (Zn) and in sediments 0.01–0.42 (Cd), 8.4–25 (Ni), 0.4–7.0 (Pb) and 9.3–199 (Zn) mg/kg (Zn > Ni > Pb > Cd). Metal concentrations were low compared with those reported in other regions and the maximum set by international monitoring organizations and coincided with the degree of industrialization and frequency of navigation activities. Relatively high metal concentrations were found in the main waterway of Colombia, the Magdalena River, which has become the sewage of the country’s 80% population. Although the contamination risk by fish consumption from the Colombian Caribbean Sea was low in the species studied, the cumulative risk produced by various pollutants from fish, other foods, air and water might exceed acceptable levels of exposure to hazardous chemicals.