title: New assessment of organic mercury formation in highly polluted sediments in the Lenga estuary, Chile.
abstract: Anomalously high levels of mercury in sediment in the Lenga estuary, Chile are comparable to the most contaminated sites previously reported elsewhere. Total mercury (Hgtotal) concentrations range from 0.5 to 129 mg kg(-1) and organic mercury (Hgorg) from 11 to 53 μg kg(-1). The highest levels are in areas near the previous wastewater outfall of a chlo-alkali plant. The results show that the proportion of Hgorg/Hgtotal in the sediment varies by more than two orders of magnitude (0.02-5.7%) according to the concentration of Hgtotal. No correlation between the concentration of Hgorg and Hgtotal was found. The lack of correlation does contrast with the findings of other authors in culture media. Our results indicate that even at very high concentrations of Hgtotal and organic matter do not influence organic mercury formation in estuary sediments. The disparity in Hgtotal and Hgorg concentrations also attests to environmental differences in the formation.
authors.affiliation: Department of Analytical and Inorganic Chemistry, Faculty of Chemical Sciences, University of Concepción, PO Box 160-C, Concepción, Chile. jyanez@udec.cl
authors.forename: Jorge
authors.initials: J
authors.lastname: Yáñez
authors.forename: Marjory
authors.initials: M
authors.lastname: Guajardo
authors.forename: Cristian
authors.initials: C
authors.lastname: Miranda
authors.forename: César
authors.initials: C
authors.lastname: Soto
authors.forename: Héctor D
authors.initials: HD
authors.lastname: Mansilla
authors.forename: A Russell
authors.initials: AR
authors.lastname: Flegal
mesh_terms: D002677:Chile; D004784:Environmental Monitoring; D063366:Estuaries; D019015:Geologic Sediments / Q000737:chemistry*; D008628:Mercury / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*; D014877:Water Pollution, Chemical / Q000706:statistics & numerical data
chemical_list: D014874:Water Pollutants, Chemical; D008628:Mercury
keywords: Mercury; Methylation assessment; Organic mercury; Sediments