Management of mercury legacy from dental amalgam in waste water

汞是一种强有力的神经毒素，在鱼类和贝类中生物积累，使其成为全球污染问题。联合国环境规划署（UNEP）指出，汞及其化合物对人类健康和环境构成严重威胁。这一问题是一个重要的环境优先事项：2017年，联合国环境规划署实施了《水俣公约》，这是一项旨在“保护人类健康和环境免受汞的不利影响”的全球条约。“通过这一条约，环境署着手逐步减少、淘汰和消除全球汞的使用。牙科是汞的主要来源;汞占传统银填充物中使用的“牙科汞合金”的50%。虽然牙科汞合金正在被塑料和陶瓷替代品所取代，但这是一个缓慢的过程，在发展中国家，汞合金仍然是主要的牙科填充材料。此外，在过去150年里，由于不加控制的处置，“遗留问题”仍然存在。在一些发达国家，牙科手术配备了“牙科汞合金分离器”;但在其他地方，将这种废物排入城市下水道的情况仍然很普遍。这些废物排入市政设施，造成了复杂的污染物遗留问题，因为重汞合金废物在污水管道中沉淀，在厌氧污泥中堆积。环境署估计，每年有数千吨汞从牙科汞合金中进入废物流，这在赤道和热带发展中国家是一个严重问题，这些国家普遍存在不受控制的废物处置，因为在这些地区，温度较高时，细菌活动会形成异常危险的生物累积神经毒素甲基汞，从而增加汞的有害影响。该项目将与英国和印度的合作伙伴一起，发展和壮大一个专门的研究小组，以确定一项战略，对废水系统中牙科汞合金中的汞进行量化。该团队的优势来自于科学与工业研究理事会（CSIR）组建的研究机构中技能高超的“特定任务”科学家，他们在汞检测和量化分析系统方面拥有独特的知识和专长。CSIR科学家将与英国谢菲尔德大学化学系的同事一起工作并分享专业知识。该小组还得到了环境署和世界卫生组织的宝贵战略支持，并表示希望与之合作。这两个组织都将印度确定为这一污染途径的“环境利益和所需行动”领域;通过这种方式，我们正在结合在“风险”地点运营的国际合作伙伴的专业知识。印度牙科协会主席已加入我们的合作团队，并将提供指导，“风险网站”的专业知识，对地方和国家的专业和政治资源，以及未来可能的资助机会的基本国家建议。该应用程序旨在发展这个强大的科学联盟，并促进概念研究的验证，以优化CSIR-CSMRI开发的灵敏的汞检测方法。我们制定的工作包旨在实现以下具体目标：（i）进一步开发和完善该测试和其他敏感方法，以确定和量化废水中的汞含量。(ii)确定废水管道内汞合金残留物积聚的目标地点。(iii)开发水传感能力，以测试污染源的“下游”。(iv)这一初步的活动方案将使我们能够发展该联盟，并申请更全面的长期资金，以有效的方式应对这一环境污染物途径的挑战。

Mercury, Hg, is a potent neurotoxin that bioaccumulates in fish and shellfish, making it a global pollution concern. The United Nations Environmental Program (UNEP) has stated that Hg and its compounds are serious risks to human health and the environment. This issue a major environmental priority: in 2017 UNEP brought into force the 'Minamata Convention,' a global treaty to "protect human health and the environment from the adverse effects of mercury." Through this treaty, UNEP sets out to phase down, phase out and eliminate global Hg use. Dentistry is a major source of Hg; the metal makes up 50% of the 'dental amalgam' used in traditional silver fillings. Although dental amalgam is being replaced by plastic and ceramic substitutes; this is a slow process and in the developing world it remains the principal dental filling material. Furthermore, a 'legacy problem' remains from its uncontrolled disposal over the last 150 years. In some developed countries, dental surgeries are equipped with 'dental amalgam separators'; but elsewhere discharge of this waste into municipal sewers is still common. The release of this waste into municipal facilities creates a complex pollutant legacy as heavy amalgam waste settles in sewerage pipes, becoming accreted in anaerobic sludge. UNEP estimates that thousands of tonnes of Hg from dental amalgam enter waste streams each year and that this is a significant problem in developing equatorial and tropical countries where uncontrolled waste disposal is widespread, as at the higher temperatures in these regions bacterial action increases the deleterious effects of Hg, by forming the exceptionally hazardous bio-accumulating neurotoxin, methyl mercury. This project will develop and grow a bespoke research team, with partners in the UK and India, to identify a strategy for the quantification of Hg from dental amalgam present in waste-water systems. The strengths of the team comes from a combination of highly skilled 'task-specific' scientists in the Research Institutes formed by the Council of Scientific & Industrial Research (CSIR) with unique knowledge and expertise in analytical systems for the detection and quantification of mercury. CSIR scientists will work and share specialist knowledge with colleagues in the Department of Chemistry at the University of Sheffield, UK. The team also has the invaluable strategic support and expressed desire for collaboration from UNEP and the World Health Organisation. Both these organisations have identified India as an area of 'environmental interest and required action' for this pollution pathway; and in this way we are combining the expertise of international collaborating partners that are operational in an 'at risk' location. The presidency of the Indian Dental Association has joined our collaborative team and will provide guidance, expertise on 'at-risk sites', essential national advice on local and national professional and political resources, and possible future funding opportunities.This application seeks to develop this powerful scientific consortium and facilitate a proof of concept study to optimise sensitive mercury detection methods developed by CSIR-CSMRI. The work packages we have developed are designed to meet specific objectives: (i) to further develop and refine this test and other sensitive methods to identify and quantify Hg content in waste water. (ii) to identify target sites where amalgam residues accrete inside waste water pipes. (iii) to develop water sensing capabilities to test 'down-stream' from a contaminant source. (iv) to electronically automate testing for the presence of mercury or methyl mercury in water or accretions in pipes.This initial programme of activities will enable us to develop the consortium and apply for more comprehensive, long-term, funding to address the challenges of this environmental pollutant pathway in an impactful way.