title: Mercury critical concentrations to Enchytraeus crypticus (Annelida: Oligochaeta) under normal and extreme conditions of moisture in tropical soils - Reproduction and survival.
abstract: Soil provides many ecosystem services that are essential to maintain its quality and healthy development of the flora, fauna and human well-being. Environmental mercury levels may harm the survival and diversity of the soil fauna. In this respect, efforts have been made to establish limit values of mercury (Hg) in soils to terrestrial fauna. Soil organisms such as earthworms and enchytraeids have intimate contact with trace metals in soil by their oral and dermal routes, reflecting the potentially adverse effects of this contaminant. The main goal of this study was to obtain Hg critical concentrations under normal and extreme conditions of moisture in tropical soils to Enchytraeus crypticus to order to assess if climate change may potentiate their acute and chronic toxicity effects. Tropical soils were sampled from of two Forest Conservation Units of the Rio de Janeiro State - Brazil, which has been contaminated by Hg atmospheric depositions. Worms were exposed to three moisture conditions, at 20%, 50% and 80% of water holding capacity, respectively, and in combination with different Hg (HgCl2) concentrations spiked in three types of tropical soil (two natural soils and one artificial soil). The tested concentrations ranged from 0 to 512mg Hg kg-1dry weight. Results indicate that the Hg toxicity is higher under increased conditions of moisture, significantly affecting survival and reproduction rate.
authors.affiliation: Department of Environmental Geochemistry, Fluminense Federal University, Outeiro São João Baptista, s/n., Centro, 24020-007 Niterói, RJ, Brazil. Electronic address: andressabuch@hotmail.com.
authors.forename: Andressa Cristhy
authors.initials: AC
authors.lastname: Buch
authors.affiliation: ECT Oekotoxikologie GmbH, Boettgerstr. 2-14, D-65439 Flörsheim/Main, Germany.
authors.forename: Rüdiger M
authors.initials: RM
authors.lastname: Schmelz
authors.affiliation: Embrapa Cerrados, BR 020 km. 18, Rodovia Brasília/Fortaleza, 73310-970 Planaltina, DF, Brazil.
authors.forename: Cintia Carla
authors.initials: CC
authors.lastname: Niva
authors.affiliation: Embrapa Agrobiology, BR 465 km. 7, 23890-000 Seropédica, RJ, Brazil.
authors.forename: Maria Elizabeth Fernandes
authors.initials: ME
authors.lastname: Correia
authors.affiliation: Department of Environmental Geochemistry, Fluminense Federal University, Outeiro São João Baptista, s/n., Centro, 24020-007 Niterói, RJ, Brazil.
authors.forename: Emmanoel Vieira
authors.initials: EV
authors.lastname: Silva-Filho
mesh_terms: D000818:Animals; D001938:Brazil; D057231:Climate Change; D004784:Environmental Monitoring; D006863:Hydrogen-Ion Concentration; D007928:Lethal Dose 50; D008628:Mercury / Q000032:analysis / Q000633:toxicity*; D019055:No-Observed-Adverse-Effect Level; D009835:Oligochaeta / Q000187:drug effects*; D012098:Reproduction / Q000187:drug effects; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis / Q000633:toxicity*; D014329:Tropical Climate; D014867:Water / Q000032:analysis*
chemical_list: D012987:Soil; D012989:Soil Pollutants; D014867:Water; D008628:Mercury
keywords: Ecotoxicity; Enchytraeids; Environmental contamination; Forest soils; Soil mesofauna; Trace metals