Relationship Between Localization of Gold Mining Areas and Hair Mercury Levels in People from Bolivar, North of Colombia

Abstract

Mercury (Hg) is a heavy metal that, once in the environment, is bioaccumulated and biomagnified through food chain impacting ecosystems. The aim of this study was to evaluate total Hg (T-Hg) concentrations in individuals along Cauca and Magdalena Rivers in Colombia, where most gold mining activities take place. A total of 1,328 hair samples were collected and analyzed for T-Hg using atomic absorption spectroscopy. T-Hg concentrations ranged from 0.01 to 20.14 μg/g. Greatest levels were detected in La Raya (5.27 ± 0.32 μg/g), Achi (2.44 ± 0.22 μg/g), and Montecristo (2.20 ± 0.20 μg/g), places that are located near gold mines. Concentrations decreased with the distance from main mining areas. Only 0.75% of the individuals had T-Hg levels above 10 μg/g. Men had significantly higher T-Hg levels than women, and correlation analysis revealed moderately weak but significant relationships between T-Hg and weight (R = 0.111, P < 0.001), stature (R = 0.111, P < 0.001), and age (R = 0.073, P = 0.007). However, T-Hg concentrations did not vary according to fish consumption frequency. Subjective health survey showed no Hg-related signs or symptoms within studied sample. However, studies are necessary to detect neurological damage linked to the metal. Changing technologies to Hg-free mining, monitoring, and educational programs are necessary to protect health of people living near Colombian rivers.

Patterns of Fish and Whale Consumption in Relation to Methylmercury in Hair among Residents of Western Canadian Arctic Communities

“…Our ndings are consistent with the literature pertaining to the relationship between intake of aquatic species and internal dose of mercury as measured in hair 22,28,[46][47][48][49][50][51][52][53][54][55][56][57][58][59][60] . Among 66 studies of this relationship identi ed by systematic review, 44 (67%) showed that increasing sh consumption was associated with increasing hair mercury concentrations 19 .…”

Content of Hg, Cd, Pb and as in fish species: a review

“…A study conducted on hair samples of 1,328 individuals, located along Cauca and Magdalena rivers, where most mining activities take place, showed that individual hair Hg average was 1.560 + 0.060 μg/g, with values oscillating between 0.010 and 20.140 μg Hg/g in hair; 52.0% of the studied population exceeded the 1.0 μg Hg/g in hair recommendation determined by USEPA. The habitants located closer to the mining areas were those who showed the highest Hg level in hair; in this study, 99.8% consumed fish at least once a day and in some cases the intake was three times a day (61). Another study conducted at Caimito, a town near San Jorge River, located in the northwestern region of Colombia, apparently free from mining activities, hair mercury levels were measured to 94 participants between 15 to 65 year-old, finding an average Hg concentration of 4.910 + 0.550 μg Hg /g in hair; no significant differences were found on Hg levels in hair by sex or age but, however, a small but significant correlation was found between fish consumption frequency and Hg levels in hair (62).…”

Mercury and gold mining in Colombia: a failed state

“…Coincidentally, studies conducted in Colombia on mercury contamination were carried out in these same areas and on the watersheds that irrigate them (Table 3). The results of these studies confirmed serious effects of mercury in the air (Cordy et al 2011), in water resources (Olivero-Verbel et al 2004), in fish (Mancera-Rodriguez and Alvarez-Leon 2006) and in humans (Medina-Mosquera et al 2011, Olivero-Verbel et al 2011.…”