Evaluation of Mercury Contamination in Chickens (Gallus gallus) and Soils in an Artisanal Gold Mining Area in San Martin De Loba, Bolivar, Colombia

The use of mercury (Hg) in artisanal gold mining in San Martin de Loba (SML), Bolivar, Colombia, poses significant environmental and health risks. This study aimed to evaluate total mercury (T-Hg) concentrations in chicken feathers (Gallus gallus) and soils from SML, and compare them with those obtained in a reference site without mining activity (Arjona). A total of 40 chickens and 30 soil samples were taken in SML, along with 31 chickens and 21 soil samples in Arjona. Using the Lumex RA-915 + analyzer, mean T-Hg levels in breast feathers, wing feather rachises, and barbs were 2.37 ± 0.42, 0.72 ± 0.32, 2.97 ± 1.26 µg/g in SML, and 0.41 ± 0.05, 0.23 ± 0.04, 0.76 ± 0.07 µg/g in Arjona, respectively. The average total mercury (T-Hg) concentration in soils from SML was 45.5 ± 12.4 µg/g, markedly exceeding the levels found in Arjona (0.04 ± 0.001 µg/g). The findings indicate severe contamination in SML soils and bioaccumulation in local birds eaten by humans, representing health risks to consumers.