Assessing and Managing the Impacts of Mixtures of Chemicals on UK Freshwater Biodiversity in a Changing World

我们正面临全球生物多样性危机，淡水生物多样性的下降速度超过陆地或海洋生物多样性。英国十分之一的淡水和湿地物种面临灭绝的威胁，三分之二的现有物种正在减少。监管数据表明，废水排放、运输、城市环境、农业和采矿造成的化学污染都导致不符合现有的质量标准。环境审计委员会最近对水质状况的总结是：“英格兰的河流一团糟。污水、农业废弃物和塑料组成的‘化学鸡尾酒’正在污染该国许多河流的水域。”然而，这些化学品对英国地表水影响的评估不太可能反映实际影响，因为它们：关注使用中的化学品的一小部分；采用单一化合物-单一端点方法；忽略化学物质、水质参数和物种相互作用的综合影响；也没有认识到生态群落的敏感性在空间和时间上是不同的。如果我们要阻止英国河流生物多样性的丧失，同时继续实现化学品的社会效益，我们迫切需要更有效的方法来评估、预测和管理化学品现在和未来的影响。我们的目标是提供并展示一个新的评估框架，该框架考虑了集水区物理化学和生态特征的已知变异性，并确定了高空间分辨率下化学物质、生物利用度调节剂和营养物质混合物对物种组合结构和功能的综合影响。该框架不仅将评估当前的化学影响，还将评估气候变化、城市化和人口增长等全球大趋势驱动的变化对未来的影响。在九个约克郡河集水区的350个地点，覆盖不同的土地用途和污染压力，我们将通过以下方式开发、测试和演示我们的框架：优先考虑排放到英国淡水中的化学物质，以确定集水区中产生影响的化学物质；2. 描述当前（2002-2022）和未来（2061-2080）英国集水区的化学暴露和一般水质参数概况；3. 评估不同水质条件下化学品对英国相关物种的影响；4. 预测化学混合物、生物利用度调节剂和营养物质对生物多样性和生态系统功能的当前和未来联合效应；和5。应用这些发现来确定干预措施，以减轻现在和未来气候和流域变化下化学品对生物多样性的影响。在本项目期间开发的理解和预测建模工具将为制定更好的计划提供信息，以适应和减轻现在和未来与水质下降有关的风险。通过与我们的合作伙伴密切合作，包括政策（JNCC），监管（HSE），主要行业（联合利华，UKWIR，网络铁路）和非政府组织（国民信托，河流信托）部门的主要代表，我们将为政策制定者提供知识和框架，以实现向化学品风险评估的范式转变，从而保护生物多样性和关键环境功能在他们脆弱的地区。监管机构和行业都将能够将未来的投资和努力集中在最有可能/实际发生危害的情况上。化学品制造商将能够更好地生产对社会有益但不会对自然环境及其提供的生态系统服务产生负面影响的化学品。只有在这个项目中采用一种综合的、全系统的方法，我们才能实现《环境法》的愿望，即“到2030年底扭转物种丰富度下降的趋势”。

We are facing a global biodiversity crisis and freshwater biodiversity is declining more rapidly than either terrestrial or marine biodiversity. One in ten freshwater and wetland species in England are threatened with extinction and two thirds of existing species are in decline. Regulatory data suggest that chemical pollution from wastewater discharges, transport, urban environments, agriculture and mining all contribute to failures against existing quality standards. The Environmental Audit Committee recently summarised the state of water quality as: "rivers in England are in a mess. A 'chemical cocktail' of sewage, agricultural waste, and plastic is polluting the waters of many of the country's rivers". However, these assessments of the impacts of chemicals on UK surface waters, are unlikely to reflect real impacts as they: focus on a small proportion of chemicals in use; take a single compound-single endpoint approach; ignore the combined effects of chemicals, water quality parameters and species interactions; and do not recognise that the sensitivity of ecological communities can vary in space and time. If we are to halt biodiversity loss in UK rivers while continuing to realise the societal benefits of chemicals, we urgently need more effective methods for assessing, predicting and managing the impacts of chemicals both now and in the future. We aim to deliver and demonstrate a new assessment framework that accounts for the known variability in the physico-chemical and ecological characteristics of a catchment and determines the combined impacts of mixtures of chemicals, bioavailability modifiers and nutrients on the structure and functioning of species assemblages at high spatial resolution. The framework will be developed not only to assess current chemical impacts but also future impacts resulting from changes driven by global megatrends such as climate change, urbanisation and population growth. Using 350 sites in nine Yorkshire river catchments covering different land-uses and pollution pressures, we will develop, test and demonstrate our framework by: 1. prioritising chemicals emitted to UK freshwaters to identify those chemicals in catchments that are driving impacts; 2. characterising current (2002-2022) and future (2061-2080) chemical exposure and general water quality parameter profiles in UK catchments; 3. estimating the effects of chemicals on UK-relevant species under different water quality conditions; 4. predicting the current and future combined effects of chemical mixtures, bioavailability modifiers and nutrients on biodiversity and ecosystem function; and 5. applying the findings to identify interventions to mitigate the impacts of chemicals on biodiversity now and under future climate and catchment change.The understanding and predictive modelling tools developed during this project will inform the development of better plans for adaptation and mitigation of risks associated with declining water quality now and in the future. By working closely with our partners, who include key representatives from the policy (JNCC), regulatory (HSE), major industry (Unilever, UKWIR, Network Rail) and NGO (National Trust, Rivers Trust) sectors, we will provide policy makers with the knowledge and frameworks to realise a paradigm shift towards chemical risk assessment that will protect biodiversity and key environmental functions in areas where they are vulnerable. Regulators and industry alike will be able to focus future investments and effort on scenarios where harm is most likely/actually occurring. Manufacturers of chemicals will be in a better position to produce chemicals that are beneficial to society but which do not negatively impact the natural environment and the ecosystem services that it provides. Only by taking an integrative and system-wide approach adopted in this project will we be able to deliver the Environment Act's aspiration to "reverse the decline in species abundance by the end of 2030".