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Laird LS, Craig EC, Clucas G, Taylor VF, Chen CY. Mercury bioaccumulation in three colonial seabird species in the Gulf of Maine. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 947:174438. [PMID: 38960193 DOI: 10.1016/j.scitotenv.2024.174438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Revised: 06/25/2024] [Accepted: 06/30/2024] [Indexed: 07/05/2024]
Abstract
The methylated form of mercury, MeHg, is a neurotoxin that bioaccumulates and biomagnifies through aquatic food webs, reaching high concentrations in top trophic species. Many seabird species are wide-ranging and feed on forage fish, so they can be used as sentinel species to assess the level of mercury in pelagic or coastal food webs because they integrate the signal from large areas and from lower trophic levels. The Gulf of Maine provides habitat for many seabirds, including endangered roseate terns (Sterna dougalii), common terns (Sterna hirundo), and the southernmost breeding population of black guillemots (Cepphus grylle). Hg levels were assessed in down of newly hatched chicks of three seabird species to determine pre-hatching Hg exposure. Stable isotopes (δ15N, δ13C) in down and chick contour feathers grown after hatching were used as indicators of adult female diet in the period before laying the egg (down) and pre-fledging chick diet (contour feathers). Black guillemot down THg concentrations were 10.07 ± 2.88 μg/g (mean ± 1SD), 5.5× higher than common tern down (1.82 ± 0.436 μg /g), and 7.4× higher than roseate tern down (1.37 ± 0.518 μg/g). Black guillemots also had higher down feather δ15N values (15.1 ± 0.52 ‰) compared to common (13.0 ± 0.72 ‰) or roseate terns (12.8 ± 0.25 ‰), and in black guillemot down feathers, higher Hg concentrations were correlated with δ15N, an indicator of trophic level. Repeated testing of the same tissue types across multiple years is needed to monitor THg exposure for seabirds in the Gulf of Maine; additionally, monitoring species composition and Hg presence in prey species of the black guillemot population would help to determine the source of high THg concentrations in this species.
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Affiliation(s)
- Lenny S Laird
- Dartmouth College, Department of Biological Sciences, LSC 6044, Hanover, NH 03755, USA.
| | - Elizabeth C Craig
- Shoals Marine Laboratory (Joint Program of University of New Hampshire and Cornell University), 8 College Rd., Durham, NH 03824, USA
| | - Gemma Clucas
- Cornell Lab of Ornithology, 159 Sapsucker Woods Road, Ithaca, NY 14850, USA
| | - Viven F Taylor
- Dartmouth College, Department of Earth Sciences, 6105 Fairchild, Hanover, NH 03755, USA
| | - Celia Y Chen
- Dartmouth College, Department of Biological Sciences, LSC 6044, Hanover, NH 03755, USA
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2
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Evers DC, Ackerman JT, Åkerblom S, Bally D, Basu N, Bishop K, Bodin N, Braaten HFV, Burton MEH, Bustamante P, Chen C, Chételat J, Christian L, Dietz R, Drevnick P, Eagles-Smith C, Fernandez LE, Hammerschlag N, Harmelin-Vivien M, Harte A, Krümmel EM, Brito JL, Medina G, Barrios Rodriguez CA, Stenhouse I, Sunderland E, Takeuchi A, Tear T, Vega C, Wilson S, Wu P. Global mercury concentrations in biota: their use as a basis for a global biomonitoring framework. ECOTOXICOLOGY (LONDON, ENGLAND) 2024; 33:325-396. [PMID: 38683471 PMCID: PMC11213816 DOI: 10.1007/s10646-024-02747-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 03/06/2024] [Indexed: 05/01/2024]
Abstract
An important provision of the Minamata Convention on Mercury is to monitor and evaluate the effectiveness of the adopted measures and its implementation. Here, we describe for the first time currently available biotic mercury (Hg) data on a global scale to improve the understanding of global efforts to reduce the impact of Hg pollution on people and the environment. Data from the peer-reviewed literature were compiled in the Global Biotic Mercury Synthesis (GBMS) database (>550,000 data points). These data provide a foundation for establishing a biomonitoring framework needed to track Hg concentrations in biota globally. We describe Hg exposure in the taxa identified by the Minamata Convention: fish, sea turtles, birds, and marine mammals. Based on the GBMS database, Hg concentrations are presented at relevant geographic scales for continents and oceanic basins. We identify some effective regional templates for monitoring methylmercury (MeHg) availability in the environment, but overall illustrate that there is a general lack of regional biomonitoring initiatives around the world, especially in Africa, Australia, Indo-Pacific, Middle East, and South Atlantic and Pacific Oceans. Temporal trend data for Hg in biota are generally limited. Ecologically sensitive sites (where biota have above average MeHg tissue concentrations) have been identified throughout the world. Efforts to model and quantify ecosystem sensitivity locally, regionally, and globally could help establish effective and efficient biomonitoring programs. We present a framework for a global Hg biomonitoring network that includes a three-step continental and oceanic approach to integrate existing biomonitoring efforts and prioritize filling regional data gaps linked with key Hg sources. We describe a standardized approach that builds on an evidence-based evaluation to assess the Minamata Convention's progress to reduce the impact of global Hg pollution on people and the environment.
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Affiliation(s)
- David C Evers
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA.
| | - Joshua T Ackerman
- U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, 800 Business Park Drive, Suite D, Dixon, CA, 95620, USA
| | | | - Dominique Bally
- African Center for Environmental Health, BP 826 Cidex 03, Abidjan, Côte d'Ivoire
| | - Nil Basu
- Faculty of Agricultural and Environmental Sciences, McGill University, Montreal, QC, Canada
| | - Kevin Bishop
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Upsalla, Sweden
| | - Nathalie Bodin
- Research Institute for Sustainable Development Seychelles Fishing Authority, Victoria, Seychelles
| | | | - Mark E H Burton
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA
| | - Paco Bustamante
- Littoral, Environnement et Sociétés (LIENSs), UMR 7266 CNRS La Rochelle Université, 2 Rue Olympe de Gouges, 17000, La Rochelle, France
| | - Celia Chen
- Department of Biological Sciences, Dartmouth College, Hanover, NH, 03755, USA
| | - John Chételat
- Environment and Cliamte Change Canada, National Wildlife Research Centre, Ottawa, ON, K1S 5B6, Canada
| | - Linroy Christian
- Department of Analytical Services, Dunbars, Friars Hill, St John, Antigua and Barbuda
| | - Rune Dietz
- Department of Ecoscience, Aarhus University, Arctic Research Centre (ARC), Department of Ecoscience, P.O. Box 358, DK-4000, Roskilde, Denmark
| | - Paul Drevnick
- Teck American Incorporated, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada
| | - Collin Eagles-Smith
- U.S. Geological Survey, Forest and Rangeland Ecosystem Science Center, 3200 SW Jefferson Way, Corvallis, OR, 97331, USA
| | - Luis E Fernandez
- Sabin Center for Environment and Sustainability and Department of Biology, Wake Forest University, Winston-Salem, NC, 29106, USA
- Centro de Innovación Científica Amazonica (CINCIA), Puerto Maldonado, Madre de Dios, Peru
| | - Neil Hammerschlag
- Shark Research Foundation Inc, 29 Wideview Lane, Boutiliers Point, NS, B3Z 0M9, Canada
| | - Mireille Harmelin-Vivien
- Aix-Marseille Université, Université de Toulon, CNRS/INSU/IRD, Institut Méditerranéen d'Océanologie (MIO), UM 110, Campus de Luminy, case 901, 13288, Marseille, cedex 09, France
| | - Agustin Harte
- Basel, Rotterdam and Stockholm Conventions Secretariat, United Nations Environment Programme (UNEP), Chem. des Anémones 15, 1219, Vernier, Geneva, Switzerland
| | - Eva M Krümmel
- Inuit Circumpolar Council-Canada, Ottawa, Canada and ScienTissiME Inc, Barry's Bay, ON, Canada
| | - José Lailson Brito
- Universidade do Estado do Rio de Janeiro, Rua Sao Francisco Xavier, 524, Sala 4002, CEP 20550-013, Maracana, Rio de Janeiro, RJ, Brazil
| | - Gabriela Medina
- Director of Basel Convention Coordinating Centre, Stockholm Convention Regional Centre for Latin America and the Caribbean, Hosted by the Ministry of Environment, Montevideo, Uruguay
| | | | - Iain Stenhouse
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA
| | - Elsie Sunderland
- Harvard University, Pierce Hall 127, 29 Oxford Street, Cambridge, MA, 02138, USA
| | - Akinori Takeuchi
- National Institute for Environmental Studies, Health and Environmental Risk Division, 16-2 Onogawa Tsukuba, Ibaraki, 305-8506, Japan
| | - Tim Tear
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA
| | - Claudia Vega
- Centro de Innovaccion Cientifica Amazonica (CINCIA), Jiron Ucayali 750, Puerto Maldonado, Madre de Dios, 17001, Peru
| | - Simon Wilson
- Arctic Monitoring and Assessment Programme (AMAP) Secretariat, N-9296, Tromsø, Norway
| | - Pianpian Wu
- Department of Biological Sciences, Dartmouth College, Hanover, NH, 03755, USA
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3
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Xiang Y, Liu G, Yin Y, Cai Y. Periphyton as an important source of methylmercury in Everglades water and food web. JOURNAL OF HAZARDOUS MATERIALS 2021; 410:124551. [PMID: 33223320 DOI: 10.1016/j.jhazmat.2020.124551] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 09/23/2020] [Accepted: 11/10/2020] [Indexed: 06/11/2023]
Abstract
Periphyton is ubiquitous in Florida Everglades and has a profound effect on mercury (Hg) cycling. Enhanced methylmercury (MeHg) production in periphyton has been well documented, but the re-distribution of MeHg from periphyton remains unknown. In this study, periphyton, sediments, surface water, periphyton overlying water, and periphyton porewater were collected from Everglades for analyzing the distribution of MeHg and total Hg (THg). Results showed that there were no significant differences in THg and MeHg in different types of periphyton, but they all displayed higher MeHg levels than sediments. MeHg distribution coefficients (logkd) in periphyton were lower than in sediments, suggesting that periphyton MeHg could be more labile entering aquatic cycling and bioaccumulation. In water, the more the distance of water samples taken from periphyton, the lower the MeHg and dissolved organic carbon concentrations were detected. In extracellular polymeric substances of periphyton, MeHg in colloidal fractions was significantly higher than that in capsular fractions. It was estimated that approximately 10% (or 1.35 kg) of periphyton MeHg were passed on to mosquitofish entering the food web during wet season, contributing 73% of total Hg stocked in mosquitofish. These results revealed the importance of periphyton on water MeHg distribution and MeHg bioaccumulation in Everglades.
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Affiliation(s)
- Yuping Xiang
- Department of Chemistry & Biochemistry and Southeast Environmental Research Center, Florida International University, 11200 SW 8th ST, Miami, FL 33199, USA; Laboratory of Environmental Nanotechnology and Health Effect, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Guangliang Liu
- Department of Chemistry & Biochemistry and Southeast Environmental Research Center, Florida International University, 11200 SW 8th ST, Miami, FL 33199, USA
| | - Yongguang Yin
- Laboratory of Environmental Nanotechnology and Health Effect, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yong Cai
- Department of Chemistry & Biochemistry and Southeast Environmental Research Center, Florida International University, 11200 SW 8th ST, Miami, FL 33199, USA; Laboratory of Environmental Nanotechnology and Health Effect, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
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4
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Eckley CS, Gilmour CC, Janssen S, Luxton TP, Randall PM, Whalin L, Austin C. The assessment and remediation of mercury contaminated sites: A review of current approaches. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 707:136031. [PMID: 31869604 PMCID: PMC6980986 DOI: 10.1016/j.scitotenv.2019.136031] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 12/07/2019] [Accepted: 12/07/2019] [Indexed: 04/13/2023]
Abstract
Remediation of mercury (Hg) contaminated sites has long relied on traditional approaches, such as removal and containment/capping. Here we review contemporary practices in the assessment and remediation of industrial-scale Hg contaminated sites and discuss recent advances. Significant improvements have been made in site assessment, including the use of XRF to rapidly identify the spatial extent of contamination, Hg stable isotope fractionation to identify sources and transformation processes, and solid-phase characterization (XAFS) to evaluate Hg forms. The understanding of Hg bioavailability for methylation has been improved by methods such as sequential chemical extractions and porewater measurements, including the use of diffuse gradient in thin-film (DGT) samplers. These approaches have shown varying success in identifying bioavailable Hg fractions and further study and field applications are needed. The downstream accumulation of methylmercury (MeHg) in biota is a concern at many contaminated sites. Identifying the variables limiting/controlling MeHg production-such as bioavailable inorganic Hg, organic carbon, and/or terminal electron acceptors (e.g. sulfate, iron) is critical. Mercury can be released from contaminated sites to the air and water, both of which are influenced by meteorological and hydrological conditions. Mercury mobilized from contaminated sites is predominantly bound to particles, highly correlated with total sediment solids (TSS), and elevated during stormflow. Remediation techniques to address Hg contamination can include the removal or containment of Hg contaminated materials, the application of amendments to reduce mobility and bioavailability, landscape/waterbody manipulations to reduce MeHg production, and food web manipulations through stocking or extirpation to reduce MeHg accumulated in desired species. These approaches often rely on knowledge of the Hg forms/speciation at the site, and utilize physical, chemical, thermal and biological methods to achieve remediation goals. Overall, the complexity of Hg cycling allows many different opportunities to reduce/mitigate impacts, which creates flexibility in determining suitable and logistically feasible remedies.
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Affiliation(s)
- Chris S Eckley
- U.S. Environmental Protection Agency, Region-10, 1200 6th Ave, Seattle, WA 98101, USA.
| | - Cynthia C Gilmour
- Smithsonian Environmental Research Center, 647 Contees Wharf Rd., Edgewater, MD 21037-0028, USA.
| | - Sarah Janssen
- USGS Upper Midwest Water Science Center, 8505 Research Way, Middleton, WI 53562, USA.
| | - Todd P Luxton
- US Environmental Protection Agency, Office of Research and Development, National Risk Management Research Laboratory, 26 West Martin Luther King Drive, Cincinnati, OH 45268, USA.
| | - Paul M Randall
- US Environmental Protection Agency, Office of Research and Development, Cincinnati, OH, USA.
| | - Lindsay Whalin
- San Francisco Bay Water Board, 1515 Clay St., Ste. 1400, Oakland, CA 94612, USA.
| | - Carrie Austin
- San Francisco Bay Water Board, 1515 Clay St., Ste. 1400, Oakland, CA 94612, USA.
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5
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Broadley HJ, Cottingham KL, Baer NA, Weathers KC, Ewing HA, Chaves-Ulloa R, Chickering J, Wilson AM, Shrestha J, Chen CY. Factors affecting MeHg bioaccumulation in stream biota: the role of dissolved organic carbon and diet. ECOTOXICOLOGY (LONDON, ENGLAND) 2019; 28:949-963. [PMID: 31410744 PMCID: PMC6814552 DOI: 10.1007/s10646-019-02086-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 07/22/2019] [Indexed: 05/15/2023]
Abstract
The bioaccumulation of the neurotoxin methylmercury (MeHg) in freshwater ecosystems is thought to be mediated by both water chemistry (e.g., dissolved organic carbon [DOC] and dissolved mercury [Hg]) and diet (e.g., trophic position and diet composition). Hg in small streams is of particular interest given their role as a link between terrestrial and aquatic processes. Terrestrial processes determine the quantity and quality of streamwater DOC, which in turn influence the quantity and bioavailability of dissolved MeHg. To better understand the effects of water chemistry and diet on Hg bioaccumulation in stream biota, we measured DOC and dissolved Hg in stream water and mercury concentration in three benthic invertebrate taxa and three fish species across up to 12 tributary streams in a forested watershed in New Hampshire, USA. As expected, dissolved total mercury (THg) and MeHg concentrations increased linearly with DOC. However, mercury concentrations in fish and invertebrates varied non-linearly, with maximum bioaccumulation at intermediate DOC concentrations, which suggests that MeHg bioavailability may be reduced at high levels of DOC. Further, MeHg and THg concentrations in invertebrates and fish, respectively, increased with δ15N (suggesting trophic position) but were not associated with δ13C. These results show that even though MeHg in water is strongly determined by DOC concentrations, mercury bioaccumulation in stream food webs is the result of both MeHg availability in stream water and trophic position.
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Affiliation(s)
- Hannah J Broadley
- Department of Environmental Conservation, University of Massachusetts, Amherst, MA, 01003, USA.
- Department of Biological Sciences, Dartmouth College, Hanover, NH, 03755, USA.
- Environmental Studies Program, Bates College, Lewiston, ME, 04240, USA.
| | | | - Nicholas A Baer
- Department of Natural and Environmental Sciences, Colby-Sawyer College, New London, NH, 03257, USA
| | | | - Holly A Ewing
- Environmental Studies Program, Bates College, Lewiston, ME, 04240, USA
| | - Ramsa Chaves-Ulloa
- Department of Biological Sciences, Dartmouth College, Hanover, NH, 03755, USA
- Department of General Education, Western Governors University, Salt Lake City, UT, USA
| | - Jessica Chickering
- Department of Natural and Environmental Sciences, Colby-Sawyer College, New London, NH, 03257, USA
| | - Adam M Wilson
- Department of Natural and Environmental Sciences, Colby-Sawyer College, New London, NH, 03257, USA
| | - Jenisha Shrestha
- Department of Natural and Environmental Sciences, Colby-Sawyer College, New London, NH, 03257, USA
| | - Celia Y Chen
- Department of Biological Sciences, Dartmouth College, Hanover, NH, 03755, USA
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6
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Eckley CS, Luxton TP, Goetz J, McKernan J. Water-level fluctuations influence sediment porewater chemistry and methylmercury production in a flood-control reservoir. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2017; 222:32-41. [PMID: 28104341 PMCID: PMC6498431 DOI: 10.1016/j.envpol.2017.01.010] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 12/15/2016] [Accepted: 01/07/2017] [Indexed: 05/26/2023]
Abstract
Reservoirs typically have elevated fish mercury (Hg) levels compared to natural lakes and rivers. A unique feature of reservoirs is water-level management which can result in sediment exposure to the air. The objective of this study is to identify how reservoir water-level fluctuations impact Hg cycling, particularly the formation of the more toxic and bioaccumulative methylmercury (MeHg). Total-Hg (THg), MeHg, stable isotope methylation rates and several ancillary parameters were measured in reservoir sediments (including some in porewater and overlying water) that are seasonally and permanently inundated. The results showed that sediment and porewater MeHg concentrations were over 3-times higher in areas experiencing water-level fluctuations compared to permanently inundated sediments. Analysis of the data suggest that the enhanced breakdown of organic matter in sediments experiencing water-level fluctuations has a two-fold effect on stimulating Hg methylation: 1) it increases the partitioning of inorganic Hg from the solid phase into the porewater phase (lower log Kd values) where it is more bioavailable for methylation; and 2) it increases dissolved organic carbon (DOC) in the porewater which can stimulate the microbial community that can methylate Hg. Sulfate concentrations and cycling were enhanced in the seasonally inundated sediments and may have also contributed to increased MeHg production. Overall, our results suggest that reservoir management actions can have an impact on the sediment-porewater characteristics that affect MeHg production. Such findings are also relevant to natural water systems that experience wetting and drying cycles, such as floodplains and ombrotrophic wetlands.
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Affiliation(s)
- Chris S Eckley
- US Environmental Protection Agency, Region-10. 1200, 6th Ave Seattle, WA 98101, USA
| | - Todd P Luxton
- US Environmental Protection Agency, Office of Research and Development, National Risk Management Research Laboratory, 26 West Martin Luther King Drive, Cincinnati, OH 45268, USA.
| | - Jennifer Goetz
- US Environmental Protection Agency, Office of Research and Development, National Risk Management Research Laboratory, 26 West Martin Luther King Drive, Cincinnati, OH 45268, USA
| | - John McKernan
- US Environmental Protection Agency, Office of Research and Development, National Risk Management Research Laboratory, 26 West Martin Luther King Drive, Cincinnati, OH 45268, USA
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7
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Lanza WG, Achá D, Point D, Masbou J, Alanoca L, Amouroux D, Lazzaro X. Association of a Specific Algal Group with Methylmercury Accumulation in Periphyton of a Tropical High-Altitude Andean Lake. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2017; 72:1-10. [PMID: 27822581 DOI: 10.1007/s00244-016-0324-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Accepted: 10/21/2016] [Indexed: 06/06/2023]
Abstract
Periphyton relevance for methylmercury (MeHg) production and accumulation are now well known in aquatic ecosystems. Sulfate-reducing bacteria and other microbial groups were identified as the main MeHg producers, but the effect of periphyton algae on the accumulation and transfer of MeHg to the food web remains little studied. Here we investigated the role of specific groups of algae on MeHg accumulation in the periphyton of Schoenoplectus californicus ssp. (Totora) and Myriophyllum sp. in Uru Uru, a tropical high-altitude Bolivian lake with substantial fishing and mining activities accruing around it. MeHg concentrations were most strongly related to the cell abundance of the Chlorophyte genus Oedogonium (r 2 = 0.783, p = 0.0126) and to no other specific genus despite the presence of other 34 genera identified. MeHg was also related to total chlorophyll-a (total algae) (r 2 = 0.675, p = 0.0459), but relations were more significant with chlorophyte cell numbers, chlorophyll-b (chlorophytes), and chlorophyll-c (diatoms and dinoflagellates) (r 2 = 0.72, p = 0.028, r 2 = 0.744, p = 0.0214, and r 2 = 0.766, p = 0.0161 respectively). However, Oedogonium explains most variability of chlorophytes and chlorophyll-c (r 2 = 0.856, p = < 0.001 and r 2 = 0.619, p = 0.002, respectively), suggesting it is the most influential group for MeHg accumulation and periphyton algae composition at this particular location and given time.
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Affiliation(s)
- William G Lanza
- Carrera de Biología, Unidad de Calidad Ambiental, Instituto de Ecología, Universidad Mayor de San Andrés, La Paz, Bolivia
| | - Darío Achá
- Carrera de Biología, Unidad de Calidad Ambiental, Instituto de Ecología, Universidad Mayor de San Andrés, La Paz, Bolivia.
| | - David Point
- Institut de Recherche pour le Dev́eloppement, Université de Toulouse III, CNRS, IRD, 31400, Toulouse, France
| | - Jeremy Masbou
- Institut de Recherche pour le Dev́eloppement, Université de Toulouse III, CNRS, IRD, 31400, Toulouse, France
| | - Lucia Alanoca
- Institut de Recherche pour le Dev́eloppement, Université de Toulouse III, CNRS, IRD, 31400, Toulouse, France
- LCABIE-IPREM, UMR 5254 - CNRS, Université de Pau et des Pays de l'Adour, 64053, Pau, France
| | - David Amouroux
- Institut de Recherche pour le Dev́eloppement, Université de Toulouse III, CNRS, IRD, 31400, Toulouse, France
- LCABIE-IPREM, UMR 5254 - CNRS, Université de Pau et des Pays de l'Adour, 64053, Pau, France
| | - Xavier Lazzaro
- Unité Mixte de Recherche Biologie des Organismes et Ecosystèmes Aquatiques (BOREA UMR 7208), Muséum National d'Histoire Naturelle, Université Pierre et Marie Curie, Université de Caen Basse-Normandie, Centre National de la Recherche Scientifique, Institut de Recherche pour le Développement-207; CP53, 61 rue Buffon, 75005, Paris, France
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8
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Donovan PM, Blum JD, Singer MB, Marvin-DiPasquale M, Tsui MTK. Methylmercury degradation and exposure pathways in streams and wetlands impacted by historical mining. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 568:1192-1203. [PMID: 27234290 DOI: 10.1016/j.scitotenv.2016.04.139] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2016] [Revised: 04/19/2016] [Accepted: 04/19/2016] [Indexed: 06/05/2023]
Abstract
Monomethyl mercury (MMHg) and total mercury (THg) concentrations and Hg stable isotope ratios (δ(202)Hg and Δ(199)Hg) were measured in sediment and aquatic organisms from Cache Creek (California Coast Range) and Yolo Bypass (Sacramento Valley). Cache Creek sediment had a large range in THg (87 to 3870ng/g) and δ(202)Hg (-1.69 to -0.20‰) reflecting the heterogeneity of Hg mining sources in sediment. The δ(202)Hg of Yolo Bypass wetland sediment suggests a mixture of high and low THg sediment sources. Relationships between %MMHg (the percent ratio of MMHg to THg) and Hg isotope values (δ(202)Hg and Δ(199)Hg) in fish and macroinvertebrates were used to identify and estimate the isotopic composition of MMHg. Deviation from linear relationships was found between %MMHg and Hg isotope values, which is indicative of the bioaccumulation of isotopically distinct pools of MMHg. The isotopic composition of pre-photodegraded MMHg (i.e., subtracting fractionation from photochemical reactions) was estimated and contrasting relationships were observed between the estimated δ(202)Hg of pre-photodegraded MMHg and sediment IHg. Cache Creek had mass dependent fractionation (MDF; δ(202)Hg) of at least -0.4‰ whereas Yolo Bypass had MDF of +0.2 to +0.5‰. This result supports the hypothesis that Hg isotope fractionation between IHg and MMHg observed in rivers (-MDF) is unique compared to +MDF observed in non-flowing water environments such as wetlands, lakes, and the coastal ocean.
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Affiliation(s)
- Patrick M Donovan
- University of Michigan, Department of Earth and Environmental Sciences, 1100 N., University Ave., Ann Arbor, MI 48109, USA.
| | - Joel D Blum
- University of Michigan, Department of Earth and Environmental Sciences, 1100 N., University Ave., Ann Arbor, MI 48109, USA
| | - Michael Bliss Singer
- University of St Andrews, Department of Earth and Environmental Sciences, North St., St. Andrews, KY16 9AL, UK; Earth Research Institute, University of California Santa Barbara, Santa Barbara, CA, 91306, USA
| | | | - Martin T K Tsui
- Department of Biology, University of North Carolina at Greensboro, Greensboro, NC 27402, USA
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9
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Singer MB, Harrison LR, Donovan PM, Blum JD, Marvin-DiPasquale M. Hydrologic indicators of hot spots and hot moments of mercury methylation potential along river corridors. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 568:697-711. [PMID: 26994752 DOI: 10.1016/j.scitotenv.2016.03.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 03/01/2016] [Accepted: 03/02/2016] [Indexed: 06/05/2023]
Abstract
The biogeochemical cycling of metals and other contaminants in river-floodplain corridors is controlled by microbial activity responding to dynamic redox conditions. Riverine flooding thus has the potential to affect speciation of redox-sensitive metals such as mercury (Hg). Therefore, inundation history over a period of decades potentially holds information on past production of bioavailable Hg. We investigate this within a Northern California river system with a legacy of landscape-scale 19th century hydraulic gold mining. We combine hydraulic modeling, Hg measurements in sediment and biota, and first-order calculations of mercury transformation to assess the potential role of river floodplains in producing monomethylmercury (MMHg), a neurotoxin which accumulates in local and migratory food webs. We identify frequently inundated floodplain areas, as well as floodplain areas inundated for long periods. We quantify the probability of MMHg production potential (MPP) associated with hydrology in each sector of the river system as a function of the spatial patterns of overbank inundation and drainage, which affect long-term redox history of contaminated sediments. Our findings identify river floodplains as periodic, temporary, yet potentially important, loci of biogeochemical transformation in which contaminants may undergo change during limited periods of the hydrologic record. We suggest that inundation is an important driver of MPP in river corridors and that the entire flow history must be analyzed retrospectively in terms of inundation magnitude and frequency in order to accurately assess biogeochemical risks, rather than merely highlighting the largest floods or low-flow periods. MMHg bioaccumulation within the aquatic food web in this system may pose a major risk to humans and waterfowl that eat migratory salmonids, which are being encouraged to come up these rivers to spawn. There is a long-term pattern of MPP under the current flow regime that is likely to be accentuated by increasingly common large floods with extended duration.
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Affiliation(s)
- Michael Bliss Singer
- Department of Earth & Environmental Sciences, University of St Andrews, St Andrews, UK; Earth Research Institute, University of California Santa Barbara, Santa Barbara, CA, USA.
| | - Lee R Harrison
- Earth Research Institute, University of California Santa Barbara, Santa Barbara, CA, USA; NOAA Fisheries, Santa Cruz, CA, USA
| | - Patrick M Donovan
- Department of Earth & Environmental Sciences, University of Michigan, Ann Arbor, MI, USA
| | - Joel D Blum
- Department of Earth & Environmental Sciences, University of Michigan, Ann Arbor, MI, USA
| | - Mark Marvin-DiPasquale
- National Research Program, Water Resources Division, US Geological Survey, Menlo Park, CA, USA
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10
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Chaves-Ulloa R, Taylor BW, Broadley HJ, Cottingham KL, Baer NA, Weathers KC, Ewing HA, Chen CY. Dissolved organic carbon modulates mercury concentrations in insect subsidies from streams to terrestrial consumers. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2016; 26:1771-1784. [PMID: 27755696 PMCID: PMC5070544 DOI: 10.1890/15-0025.1] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Revised: 02/11/2016] [Accepted: 02/15/2016] [Indexed: 05/28/2023]
Abstract
Mercury (Hg) concentrations in aquatic environments have increased globally, exposing consumers of aquatic organisms to high Hg levels. For both aquatic and terrestrial consumers, exposure to Hg depends on their food sources as well as environmental factors influencing Hg bioavailability. The majority of the research on the transfer of methylmercury (MeHg), a toxic and bioaccumulating form of Hg, between aquatic and terrestrial food webs has focused on terrestrial piscivores. However, a gap exists in our understanding of the factors regulating MeHg bioaccumulation by non-piscivorous terrestrial predators, specifically consumers of adult aquatic insects. Because dissolved organic carbon (DOC) binds tightly to MeHg, affecting its transport and availability in aquatic food webs, we hypothesized that DOC affects MeHg transfer from stream food webs to terrestrial predators feeding on emerging adult insects. We tested this hypothesis by collecting data over 2 years from 10 low-order streams spanning a broad DOC gradient in the Lake Sunapee watershed in New Hampshire, USA. We found that streamwater MeHg concentration increased linearly with DOC concentration. However, streams with the highest DOC concentrations had emerging stream prey and spiders with lower MeHg concentrations than streams with intermediate DOC concentrations; a pattern that is similar to fish and larval aquatic insects. Furthermore, high MeHg concentrations found in spiders show that MeHg transfer in adult aquatic insects is an overlooked but potentially significant pathway of MeHg bioaccumulation in terrestrial food webs. Our results suggest that although MeHg in water increases with DOC, MeHg concentrations in stream and terrestrial consumers did not consistently increase with increases in streamwater MeHg concentrations. In fact, there was a change from a positive to a negative relationship between aqueous exposure and bioaccumulation at streamwater MeHg concentrations associated with DOC above ~5 mg/L. Thus, our study highlights the importance of stream DOC for MeHg dynamics beyond stream boundaries, and shows that factors modulating MeHg bioavailability in aquatic systems can affect the transfer of MeHg to terrestrial predators via aquatic subsidies.
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Affiliation(s)
- Ramsa Chaves-Ulloa
- Department of Biological Sciences, Dartmouth College, 78 College Street, Hanover, New Hampshire, 03755, USA.
| | - Brad W Taylor
- Department of Biological Sciences, Dartmouth College, 78 College Street, Hanover, New Hampshire, 03755, USA
| | - Hannah J Broadley
- Department of Biological Sciences, Dartmouth College, 78 College Street, Hanover, New Hampshire, 03755, USA
- Environmental Studies Program, Bates College, 7 Andrews Road, Lewiston, Maine, 04240, USA
| | - Kathryn L Cottingham
- Department of Biological Sciences, Dartmouth College, 78 College Street, Hanover, New Hampshire, 03755, USA
| | - Nicholas A Baer
- Department of Natural Sciences, Colby-Sawyer College, 541 Main Street, New London, New Hampshire, 03257, USA
| | - Kathleen C Weathers
- Cary Institute of Ecosystem Studies, PO Box AB, Millbrook, New York, 12545, USA
| | - Holly A Ewing
- Environmental Studies Program, Bates College, 7 Andrews Road, Lewiston, Maine, 04240, USA
| | - Celia Y Chen
- Department of Biological Sciences, Dartmouth College, 78 College Street, Hanover, New Hampshire, 03755, USA
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11
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Klaus JE, Hammerschmidt CR, Costello DM, Burton GA. Net methylmercury production in 2 contrasting stream sediments and associated accumulation and toxicity to periphyton. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2016; 35:1759-1765. [PMID: 26636557 DOI: 10.1002/etc.3324] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Revised: 11/15/2015] [Accepted: 12/03/2015] [Indexed: 06/05/2023]
Abstract
Periphyton uptake of bioaccumulative methylmercury (MeHg) may be an important entryway into the food web of many stream ecosystems where periphyton can be dominant primary producers. The net production of MeHg in stream sediment, its bioaccumulation in periphyton, and the potential toxicity of divalent Hg (Hg[II]) and MeHg in sediment to periphyton were investigated with a 67-d in situ incubation experiment using chemical exposure substrates containing either a fine-grained, organic-rich or a sandy, low-organic sediment, each amended with varying concentrations of mercuric chloride. Methylmercury was produced in sediment, and concentrations increased with greater amounts of added Hg(II); however, the net production of MeHg was inhibited in the highest Hg(II) treatments of both sediments. The range of total Hg concentrations that inhibited MeHg production was between approximately 80 000 ng Hg and 350 000 ng Hg per gram of organic matter for both sediments. Periphyton colonizing substrates accumulated MeHg in proportion to the concentration in sediment, but periphyton exposed to the sandy sediment accumulated approximately 20-fold more than those exposed to the organic-rich sediment relative to sediment MeHg concentrations. Toxicity of either Hg(II) or MeHg to periphyton was not observed with either periphyton organic content, net primary production, or respiration as endpoints. These results suggest that in situ production and bioaccumulation of MeHg in stream ecosystems can vary as a function of sediment characteristics and Hg(II) loadings to the sediment. Environ Toxicol Chem 2016;35:1759-1765. © 2015 SETAC.
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Affiliation(s)
- Jaclyn E Klaus
- Department of Earth & Environmental Sciences, Wright State University, Dayton, Ohio, USA
| | - Chad R Hammerschmidt
- Department of Earth & Environmental Sciences, Wright State University, Dayton, Ohio, USA
| | - David M Costello
- Department of Biological Sciences, Kent State University, Kent, Ohio, USA
| | - G Allen Burton
- School of Natural Resources & Environment, University of Michigan, Ann Arbor, Michigan, USA
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12
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Riscassi A, Miller C, Brooks S. Seasonal and flow-driven dynamics of particulate and dissolved mercury and methylmercury in a stream impacted by an industrial mercury source. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2016; 35:1386-1400. [PMID: 26574732 DOI: 10.1002/etc.3310] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Revised: 08/21/2015] [Accepted: 11/14/2015] [Indexed: 06/05/2023]
Abstract
Sediments and floodplain soils in the East Fork Poplar Creek watershed (Oak Ridge, TN, USA) are contaminated with high levels of mercury (Hg) from an industrial source at the headwaters. Although baseflow conditions have been monitored, concentrations of Hg and methylmercury (MeHg) during high-flow storm events, when the stream is more hydrologically connected to the floodplain, have yet to be assessed. The present study evaluated baseflow and event-driven Hg and MeHg dynamics in East Fork Poplar Creek, 5 km upstream of the confluence with Poplar Creek, to determine the importance of hydrology to in-stream concentrations and downstream loads and to ascertain whether the dynamics are comparable to those of systems without an industrial Hg source. Particulate Hg and MeHg were positively correlated with discharge (r(2) = 0.64 and 0.58, respectively) and total suspended sediment (r(2) = 0.97 and 0.89, respectively), and dissolved Hg also increased with increasing flow (r(2) = 0.18) and was associated with increases in dissolved organic carbon (r(2) = 0.65), similar to the dynamics observed in uncontaminated systems. Dissolved MeHg decreased with increases in discharge (r(2) = 0.23) and was not related to dissolved organic carbon concentrations (p = 0.56), dynamics comparable to relatively uncontaminated watersheds with a small percentage of wetlands (<10%). Although stormflows exert a dominant control on particulate Hg, particulate MeHg, and dissolved Hg concentrations and loads, baseflows were associated with the highest dissolved MeHg concentration (0.38 ng/L) and represented the majority of the annual dissolved MeHg load. Environ Toxicol Chem 2016;35:1386-1400. Published 2015 Wiley Periodicals, Inc. on behalf of SETAC. This article is a US Government work, and as such, is in the public domain in the United States of America.
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Affiliation(s)
- Ami Riscassi
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Carrie Miller
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Scott Brooks
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
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13
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Donovan PM, Blum JD, Singer MB, Marvin-DiPasquale M, Tsui MTK. Isotopic Composition of Inorganic Mercury and Methylmercury Downstream of a Historical Gold Mining Region. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:1691-702. [PMID: 26789018 DOI: 10.1021/acs.est.5b04413] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We measured total mercury (THg) and monomethyl mercury (MMHg) concentrations and mercury (Hg) isotopic compositions in sediment and aquatic organisms from the Yuba River (California, USA) to identify Hg sources and biogeochemical transformations downstream of a historical gold mining region. Sediment THg concentrations and δ(202)Hg decreased from the upper Yuba Fan to the lower Yuba Fan and the Feather River. These results are consistent with the release of Hg during gold mining followed by downstream mixing and dilution. The Hg isotopic composition of Yuba Fan sediment (δ(202)Hg = -0.38 ± 0.17‰ and Δ(199)Hg = 0.04 ± 0.03‰; mean ± 1 SD, n = 7) provides a fingerprint of inorganic Hg (IHg) that could be methylated locally or after transport downstream. The isotopic composition of MMHg in the Yuba River food web was estimated using biota with a range of %MMHg (the percent of THg present as MMHg) and compared to IHg in sediment, algae, and the food web. The estimated δ(202)Hg of MMHg prior to photodegradation (-1.29 to -1.07‰) was lower than that of IHg and we suggest this is due to mass-dependent fractionation (MDF) of up to -0.9‰ between IHg and MMHg. This result is in contrast to net positive MDF (+0.4 to +0.8‰) previously observed in lakes, estuaries, coastal oceans, and forests. We hypothesize that this unique relationship could be due to differences in the extent or pathway of biotic MMHg degradation in stream environments.
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Affiliation(s)
- Patrick M Donovan
- Department of Earth and Environmental Sciences, University of Michigan , 1100 N. University Avenue, Ann Arbor, Michigan 48109, United States
| | - Joel D Blum
- Department of Earth and Environmental Sciences, University of Michigan , 1100 N. University Avenue, Ann Arbor, Michigan 48109, United States
| | - Michael Bliss Singer
- Department of Earth and Environmental Sciences, University of St Andrews , North Street, St Andrews, KY16 9AL U.K
- Earth Research Institute, University of California Santa Barbara , Santa Barbara, California 93106 United States
| | | | - Martin T K Tsui
- Department of Biology, University of North Carolina at Greensboro , Greensboro, North Carolina 27402, United States
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