BIOLOGICAL MERCURY HOTSPOTS IN THE WATERSHEDS OF THE MESOAMERICAN BARRIER REEF SYSTEM
The Mesoamerican Barrier Reef System (MBRS) is the largest barrier reef in the Northern Hemisphere, extending over 1000 kilometers from the Yucatan Peninsula of Mexico to the Bay Islands of northern Honduras. It is a UNESCO World Heritage Site, renowned for its marine biodiversity. An estimated 2 million people from Mexico, Belize, Guatemala, and Honduras depend on the reef for their economic livelihoods.
A series of stressors are impacting the health of the reef including rapid coastal development, overfishing, and poor agricultural practices within the watersheds that drain into the reef. In addition, recent data suggest that mercury contamination may be impacting both freshwater and marine fishes of the barrier reef ecosystem. Here, we present mercury concentrations from more than 700 individual fishes including both freshwater and marine species. Freshwater fishes were collected in the major watersheds of Belize, Guatemala, and Honduras that drain into the barrier reef. Additional marine species were collected via market landings and direct capture.
Results highlight biological mercury hotspots where fish mercury concentrations are elevated above both U.S. EPA and World Health Organization human consumption guidelines. Hotspots include the Chalillo Reservoir and upper Belize River in Belize and Lago Yojoa of northern Honduras. In addition, we identify freshwater and marine species that represent both healthy and risky choices for human fish consumption. Riskier choices include amberjack, mackerel and barracuda with average mercury concentrations above 0.5 parts per million, wet weight (ppm, ww). Healthier choices are fishes with mercury concentrations below 0.3 ppm (ww) and include hogfish, spiny lobster, and several species of snapper. These data provide a potential model for future human health consumption guidelines for freshwater and marine fishes of the MBRS and also the need for more extensive research on potential sources of contaminants in the greater MBRS watershed.
FULFILLING OBLIGATIONS OF THE MINAMATA CONVENTION ON MERCURY FOR NATIONS: MINAMATA INITIAL ASSESSMENTS
In response to growing international concern about mercury pollution, the United Nations Environment Programme (UNEP) formalized the Global Mercury Partnership in 2008 to systematically eliminate anthropogenic mercury releases through strategic intervention and collaboration with national governments. As of 2009, UNEPs governing council entered negotiations for the preparation of a legally binding global instrument on mercury to safeguard human and ecosystem health. Negotiations were successfully completed in January 2013 with 147 governments agreeing on draft text. At the Conference of Plenipotentiaries on 9-11 October, 2013 in Minamata and Kumamoto, Japan, the Minamata Convention on Mercury was formally adopted and opened for signature.
The Minamata Convention has a phased approach to reduce, and where possible, eliminate mercury use in key industrial sectors. Provisions of the Convention include phase out deadlines established for supply sources and trade, mercury added products, and manufacturing processes in which mercury or mercury compounds are used. Based on these targets, the Convention is designed to systematically reduce emissions and releases to land and water, and phase out the use of mercury where alternatives exist.
To meet obligations under the Convention, several barriers must be addressed to assist in ratification. These barriers include: (1) lack of institutional capacity to implement the Convention; (2) gaps in political and legislative frameworks to support Convention provisions; (3) lack of data on sources of emissions and releases, as well as outdated national inventories of mercury stocks; and (4) low awareness of health risks associated with mercury among the public and government officials. With the adoption of the Convention, countries generally require assistance to formulate and apply sector wide programs.
The development of the Minamata Initial Assessment (MIA) addresses these barriers by providing standardized, basic and essential information to enable policy and strategic decisions to be made and assist in developing plans to identify priority sectors and activities within the country and to increase awareness of risks to human and ecosystem health. The use of financial support from the Global Environment Facility (GEF) enables nations to fulfill essential communication requirements, make informed policy decisions and assist in prioritizing activities. Over 90 countries are now conducting MIAs through GEF funding.
Biodiversity Research Institute (BRI) is an executing agency for the United Nations Environment Programme, United Nations Industrial Development Organization (UNIDO) and the United Nations Development Programme (UNDP). BRI is conducting and is now involved with MIAs in over 30 countries.
THE ROLE THAT THE CANADIAN MERCURY SCIENCE ASSESSMENT CAN PLAY TO INFORM GOVERNMENTS PLANNING THE IMPLEMENTATION OF THE MINAMATA CONVENTION
Scientific assessments are good tools used to synthesize extensive information into relevant and useful summaries on a topical issue. Generally, science assessments evaluate the past and current scientific status of an issue; identify priorities for future scientific needs and inform the scientific community on the state of research. In addition, they provide evidence for decision-making by research managers and policy-makers on scientific issues. The Canadian Mercury Science Assessment (CMSA) is the first nationally comprehensive, peer-reviewed synthesis of scientific knowledge on mercury in Canada and was released in 2016/17. This report was intended to provide information to support Canadas domestic policy and science priorities as well as provide a scientific foundation, from the Canadian perspective, for the development of efforts to reduce global mercury emissions in the implementation of the Minamata Convention.
Preparation of this assessment began with a series of workshops where science questions were developed to capture the information needs of the science and policy communities in Canada. Based on these questions, the goal of this assessment was to respond to the questions through a synthesis of knowledge on environmental mercury pollution. Results from Canadas Mercury Science Program (part of Canadas then Clean Air Regulatory Agenda) were used as a platform for the assessment as well as other mercury research programs. Researchers were tasked with quantifying current and past levels of mercury in the environment, identifying gaps in our knowledge of the transport routes from point of emission to exposure to wildlife and humans. Further, researchers were challenged to develop the capacity to predict changes in indicators associated with changes in levels of emissions of mercury or changes in the receiving environment. This information was combined in a full 15 chapter assessment report.
The CMSA consists of 3 documents: the Executive, Summary the Summary of Key Results and the full Science Assessment. The Executive Summary is a short document highlighting the high level results. The Summary of Key Results contains the answers to the policy-relevant science questions. The full Science Assessment provides an in-depth knowledge on mercury levels and processes in the Canadian environment and identifies gaps in our understanding of how mercury travels though the ecosystem, where it ends up, the impact of human activities on its chemistry and changes in mercury pollution.
A full summary of the CMSA and its impact on informing decision-makers for the Minamata Convention will be discussed.
AN ASSESSMENT OF MERCURY CONTAMINATED SITES IN LOW AND MIDDLE INCOME COUNTRIES
Pure Earths (PE) Toxic Site Identification Program (TSIP) works globally to identify and assess polluted sites that pose a risk to public health. Though not comprehensive, TSIP works to improve public health in low- and middle-income countries (LMICs) while being culturally and socially considerate and responsible.
Mercury (Hg) is a naturally occurring metal found in air, water and soil. Because of its damaging effects to public health and persistence as a global toxicant, the WHO placed mercury on its top ten list of chemicals of major public health concern. Despite being highly toxic, even in small amounts, it is used, unshielded, and released in several LMICs during the extraction of gold and ore processing.
In November 2016, data for 463 mercury-contaminated sites in LMICs were extracted from the TSIP database to review descriptive statistics where mercury (elemental, inorganic or organic) is identified as the key pollutant.
The TSIP database query notes distribution of mercury as a key pollutant as follows: 168 in Africa (36.3%), 97 in Central and South America (20.9%), 12 in China (2.6%), 37 in Eastern Europe (8.0%), 26 in South Asia (5.6%), and 123 in Southeast Asia (26.6%). 154 sites (33.3%) have verified health effects. The average population potentially at risk of mercury exposure at each site is approximately18,000. Artisanal Mining (Hand Mining), the largest industry contributing to global mercury emissions, represents nearly half (49.46%, 229 sites) of the TSIP sites with mercury as a key pollutant, distantly followed by formal Mining and Ore Processing (21.38%, 99 sites).
These results give insight into the effects of mercury and its global prevalence and detriment. The results are used by PE to prioritize limited funding to conduct additional assessment and to support cleanup at sites that have the highest risk.
THE ROLES OF THE HEALTH SECTOR IN THE MINAMATA CONVENTION IMPLEMENTATION: RAISING AWARENESS AND STRENGTHENING CAPABILITIES
In support of the Minamata Convention, the World Health Organization adopted the World Health Assembly Resolution 67.11: Public health impacts of exposure to mercury and mercury compounds: the role of WHO and ministries of public health in the implementation of the Minamata Convention. These roles are well defined and evolved from the United Nations Environment Program and International Negotiating Committee meetings, held during 2009 and 2016, in which WHO participated.
The Convention urges member states to act on the development and implementation of strategies and programs to identify and protect population at risk, particularly vulnerable populations, from exposure to mercury and mercury compounds. Recommendations include setting targets for mercury exposure reduction, and public education and awareness. In this regard, phase-out of mercury-added products in medical devices (i.e. thermometers and sphygmomanometers) and in products (i.e. antiseptics and skin-lightening cosmetics) is among the health sector responsibilities. In addition, dental amalgam use is under phase-down, for which additional resources are needed for its effective use reduction. For instance, the effective switch to non-amalgam materials should count with health insurance companies to incorporate reimbursement mechanisms; therefore providing higher economic support to persons using non-amalgam material.
Considering the significance of atmospheric mercury emission from the artisanal and small scale gold mining (ASGM) sector, the development of national action plans to eliminate or reduce mercury use is needed, especially for countries that declare ASGM as significant. Noting that public health strategies are required for ASGM national action plans, WHO/PAHO has been developing guideline documents to address development and implementation of such strategies.
Fish consumption is also a relevant aspect of the Convention, given the nutritional benefits and mercury risks involved, especially among women of reproductive age. Heavy fish-eating communities living in areas under the influence of ASGM have been considered the most vulnerable populations for methyl mercury exposure. Opportunities to further develop fish advisories, ideally based on local biomonitoring data, are warranted. - Dissemination of WHO guidelines, health sector capacity building, and coordination of information exchanges have been addressed in regional workshops conducted in Uruguay and Jamaica by WHO/PAHO, and Germany and Jordan, by respective regional offices for health representatives. To strengthen health sector capabilities, these topics above mentioned are addressed in the PAHO Virtual Campus course on mercury.
EVALUATING REPRODUCIBILITY OF MERCURY SCIENCE, MODELS AND BIOMONITORING: IMPLICATIONS FOR THE MINAMATA CONVENTION
Reproducibility is a cornerstone of the scientific method and, in principle, is an essential part of the scientific process. In recent years mercury science has evolved significantly with its use of advanced technologies and computational models to address this complex environmental and public health issue. These advances in the field have made it essential that transparency be enhanced to ensure that mercury studies are truly reproducible and scientifically sound. The goal of this presentation is to evaluate methods, results and inferential reproducibility as it relates to uncertainty in mercury research models, science, and biomonitoring. Here I use peer reviewed, published studies to evaluate reproducibility in several key mercury investigations especially with regard to how it relates to policymaking. I will provide examples of the overall principle of reproducibility and discuss the role of transparency, peer review, basic reporting and open data access standards. Lastly, I will also present a framework to reduce irreproducibility in mercury research studies, models and biomonitoring investigations in support of the Minamata Convention on Mercury.
USING SEABIRDS AS BIOMONITORS OF TEMPORAL AND SPATIAL TRENDS OF MERCURY FOR THE MINAMATA CONVENTION
Marine ecosystems are impacted at the global scale by Hg and the combined effects of climate change and human activities could lead to a dramatic increase of its bioaccumulation in marine organisms in the future. Indeed, the general warming of ocean water masses is affecting the cycle of Hg (e.g., its methylation rate), thereby increasing exposure of marine organisms. In that context, providing a large-scale and comprehensive understanding of marine food web contamination is essential to better comprehend the impacts of anthropogenic activities and climate change on bioaccumulation of Hg in marine organisms and to propose mitigation measures in the frame of the Minamata Convention. Monitoring at large scales, both spatially and temporally, are relevant to such evaluation. In this way, we propose to use seabirds as bioindicators of the environmental global contamination by Hg. Seabirds are indeed relevant organisms to monitor Hg as: 1) they are excellent indicators of Hg contamination and reflect the contamination of the entire food chain on which they rely; 2) they have a wide distribution and different species occupy various compartments of their ecosystems (inshore or offshore, benthic or surface feeders, piscivorous or zooplankton-feeders); 3) most species are colonial and philopatric, giving the opportunity to sample several individuals simultaneously and to monitor them repeatedly through time since non-lethal sampling of blood (short-time exposure) and feathers (long-term exposure) is easy in seabirds; 4) feathers can be collected from Museum specimens, allowing retrospective investigation of Hg time trends. Seabirds therefore appear to be ideal organisms to (1) monitor spatial variations of Hg in marine ecosystems at different latitudes (2) define hotspots of Hg contamination in the different large ecosystems and highlight sensitive areas that require particular attention and protection (3) carry long-term monitoring of Hg trends in the different parts of the world Ocean. An effort is now needed to generate an integrated and standardized biomonitoring network to determine spatial and temporal trends of Hg to help evaluate the effectiveness of the Minamata Convention.