Biodegradable Bioplastics - Assessing Environmental Risk (BIO-PLASTIC-RISK)

可生物降解生物塑料（BBPs）是一类具有相当大潜力的材料，可以减少由报废塑料堆积造成的全球环境挑战。bbp由可再生碳制成，如植物材料（生物塑料），由于其分子结构和由此产生的特性，与传统塑料相比，bbp被认为具有更高的生物降解率。目前，只有大约1%的塑料产品是生物塑料；在潜在优势的推动下，需求迅速增长。bbp已经广泛应用于具有实质性途径进入自然环境的应用中（农业地膜、纺织纤维、化妆品中的珠子）。然而，我们对它们在自然环境中的命运了解甚少，因为缺乏降解动力学的关键信息以及它们的分解产物（碎片和化学添加剂）的任何潜在环境影响。生物降解已在特定条件下得到证明，例如商业合成，并且有相关标准，但研究表明，在自然条件下降解可能缓慢或不完全。这项雄心勃勃，但非常容易处理的4年研究计划汇集了普利茅斯大学和巴斯大学的国际知名聚合物科学家，海洋和陆地生物学家以及生态毒理学家，普利茅斯海洋实验室，项目合作伙伴Lenzing AG和一个咨询小组，包括来自政府机构，BBP生产商，商业用户（Sainsbury's和Riverford有机农场），水务当局以及非政府组织的代表。该小组将共同确定bbp在环境中的命运，它们对生物和生态系统功能的影响，并制定环境风险评估。我们将根据bbp的组成（化学结构，添加剂）以及可用于评估环境中的劣化（分子量，厚度，强度）的特征来描述bbp。然后，我们将根据BBPs的恶化速率以及BBPs及其分解产物的途径和环境积累来确定BBPs在海洋和陆地环境中的命运。这将为检验BBP退化对海洋和陆地生物（贻贝和蚯蚓等动物以及草本和草等植物）的任何相关直接影响以及对生态和生物地球化学过程的任何间接后果的实验提供信息。总的来说，这些结果将与现有文献一起用于评估环境中BBPs的命运和行为与危害之间的关系，以便进行风险评估，以显示BBPs及其相关化学物质的浓度可能对动物及其栖息地产生影响，以及生态系统如何发挥作用。将得出土壤和水中安全水平的估计值，以及增加不确定性的因素，并指出未来研究的优先事项。潜在风险方面的结果将与评级机构的好处一起进行沟通，以提供一个平衡的视角，并帮助指导下一代评级机构的发展。这将通过出版物和利益攸关方的参与来传播，包括：与经合组织和Defra共享数据；技术利益相关者研讨会（工业、政府、咨询公司、非政府组织）。等)和一个培训活动——如何完成塑料的风险评估。媒体对塑料污染的关注相当多，这已经转化为公众采取行动的紧急呼吁。然而，目前对最适当的行动的理解尚不清楚，缺乏关于诸如bbp等新材料的益处和风险的可靠信息。因此，这项研究对于指导商业实践和政策应对的变化具有至关重要的意义，例如实施25年环境计划。

Biodegradable bioplastics (BBPs) are a category of materials that offer considerable potential to reduce the global environmental challenge resulting from the accumulation of end-of-life plastic. BBPs are made from renewable carbon such as plant material (bioplastics) and as a consequence of their molecular structure and resulting properties are regarded to have enhanced rates of biodegradation compared to conventional plastics. Currently only around 1% of plastic production is in the form of bioplastics; driven by the potential advantages demand is growing rapidly. BBPs are already widely used in applications with substantive pathways to the natural environment (agricultural mulch film, textile fibres, beads in cosmetics). Yet our understanding about their fate in the natural environment is poorly understood, because key information on the kinetics of degradation and any potential environmental effects of their breakdown products (fragments and chemical additives) is lacking. Biodegradation has been demonstrated under specific conditions, such as commercial compositing, and there are associated standards, but studies indicate degradation can be slow or incomplete under natural conditions. This ambitious, yet highly tractable, 4-year research proposal brings together internationally recognised polymer scientists, marine and terrestrial biologists and ecotoxicologists from the Universities of Plymouth and Bath together with Plymouth Marine Laboratory, Project Partner Lenzing AG and an Advisory Group including representatives from Government agencies, BBP producers, commercial users (Sainsbury's and Riverford Organic Farms), Water Authorities as well as NGOs. Collectively the team will establish the fate of BBPs in the environment, their effect on organisms and ecosystem function and develop environmental risk assessments. We will characterise BBPs in terms of their composition (chemical structure, additives) as well as features that can be used to assess deterioration (molecular weight, thickness, strength) in the environment. We will then establish the fate of BBPs in marine and terrestrial environments in terms of rates of deterioration as well as the pathways and environmental accumulation of BBPs and their breakdown products. This will inform experiments to examine any associated direct effects of BBP deterioration on marine and terrestrial organisms (animals such as mussels and earthworms and plants such as herbs and grass) and to examine any indirect consequences on ecological and biogeochemical processes. Collectively, these outcomes, together with existing literature, will be used to evaluate how the fate and behaviour of BBPs in the environment relates to hazards in order to conduct a risk assessment to show at what concentration BBPs and their associated chemicals may have an impact on animals, their habitats, and how the ecosystem functions. Estimates of safe levels in soil and water will be derived as well as factors that add uncertainty and indicate priorities for future research.Outcomes in terms of potential risks, will be communicated alongside the benefits of BBPs - so as to provide a balanced perspective and help guide development for the next generation of BBPs. This will be disseminated by publications and stakeholder engagement, including: data sharing with OECD and Defra; a technical stakeholder workshop (industry, government, consultancy, NGOs. etc) and a training event - how to complete a risk assessment for plastics.There has been considerable media attention on plastic pollution and this has translated into an urgent call for action by the public. However, current understanding of the most appropriate actions is less clear and reliable information on the benefits and risks of novel materials such as BBPs, is lacking. Hence, this research is of critical importance to guide changes in commercial practice and policy responses, such as implementation of the 25 year Environment Plan.