Investigation of selected precursors as an atmospheric source of perfluoroalkyl substances (PFAS) to the Arctic

对作为北极全氟烷基物质 (PFAS) 大气来源的选定前体进行调查

• 批准号: 1935760
• 金额: --
• 依托单位: University of Oxford
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2017
• 资助国家: 英国
• 起止时间: 2017 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-1935760
• 关键词: Investigation; selected; precursors; atmospheric; source

Since the implication of the Stockholm Convention trends in abiota of persistent organic pollutants (POPs) have been observed to be decreasing in Svalbard and, in a broader sense, many aspects of the sources, sinks and transport of POPs are now well understood.Originally POPs were used as pesticides, industrial chemicals and industrial by-products, however they soon proved to be ubiquitous in the environment.However, since ratification of the Stockholm Convention, a further sixteen compounds have been found to express the same POP characteristics - persistent,bioaccumalative6 and toxic.Hence, it is important that further potential substances are identified early and understood on spatial and temporal extends so they can be monitored.Svalbard exists with differing climates in the east compared to the west. The west of the islands experiences a milder climate due to the jet stream bring warm water and a milder weather.In contrast, the east coast receives cold and fresh currents from the Arctic ocean, with air masses typically originating in Eurasia.This sets up Svalbard as an ideal location to access the transport pathways of pollutants due to the different climate gradients that exist within the archipelago.The Arctic Monitoring Assessment Programme has outlined several substances and chemicals of emerging Arctic concern (CEACs) which exhibit POP-like properties.Such species that have been identified and require further attention in the Svalbard archipelago are polyfluoronated alkyl substances (PFAS) and microplastics.It is the intention of this project to shed further light on the temporal and spatial understanding of these substances.With respect to PFAS, they are formed by oxidation during long range atmospheric transport (LRAT) from fluorotelomer alcohols (FTOHs) and upon arrival in polar regions they become deposited by wet or dry deposition.However little is known about their abundance and distribution in the Arctic.This projects aims to take snow samples on three spatial gradients.Firstly, on an east-west gradient to attempt to establish which air masses may be responsible for their LRAT.Secondly on a latitude gradient to understand the potential for PFAS to undergo global fractionation.Finally, sampling will be undertaken with varying elevation to access fractionation due to altitude.It is hoped that results from these studies will assist with understanding data taken on a temporal scale. Lake sediments,snow pits and shallow ice cores will build up an understanding on temporal scales.This should also offer an insight into what extent the archipelago is polluted by PFAS through LRAT compared to local sources in settlements.Samples will be extracted and analysed using established methodology.Very little is understood concerning microplastic abundance and distribution in Svalbard's waters, the Barents Sea and the Arctic Ocean with only single studies existing in the latter two areas.However, it is notable that microplastics in sea ice has been found to be several orders of magnitude higher than Atlantic and Pacific oceanic gyres.Hence it has been hypothesised that the formation of new sea ice may scavenge such particles, concentrating microplastics in sea ice.Indeed it may be that the Arctic Ocean represents a major global sink of microplastics.This project would aim to test this hypothesis further, by comparison of sea ice cores and sea water surrounding Svalbard. Furthermore, sea water and sea ice would also be tested to understand if Svalbard's fjords also act as a potential sink, and what role local sources have to play in polluting these coastal areas.Microplastics will be isolated and identified using existing methodology.This allows for data to be readily comparable.Whilst microplastics and PFAS share little physical and chemical properties in common, both substances are known to be toxic.It is hoped that through further monitoring, the abundance and distribution of these substances in the Svalbard Archipelago

自《斯德哥尔摩公约》生效以来，斯瓦尔巴特群岛的持久性有机污染物（POP）的生物区系呈下降趋势，从更广泛的意义上说，现在对POP的来源、汇和迁移的许多方面都有了很好的了解。最初，POP被用作杀虫剂、工业化学品和工业副产品，但不久就证明它们在环境中无处不在。然而，自《斯德哥尔摩公约》批准以来，又发现了16种具有持久性、生物降解性6和毒性等持久性有机污染物特性的化合物。因此，必须及早确定更多的潜在物质，并了解其空间和时间范围，以便对其进行监测。群岛的西部由于急流带来温暖的海水和温和的天气而经历了温和的气候。相比之下，东海岸接受来自北冰洋的寒冷和新鲜的水流，由于斯瓦尔巴群岛的气候梯度不同，因此，该群岛是进入污染物输送路径的理想地点。北极监测评估方案概述了几种表现出类似持久性有机污染物特性的北极新出现关注的物质和化学品。在斯瓦尔巴群岛已经确定并需要进一步关注的物种是多氟烷基物质（PFAS）和微塑料。该项目的目的是进一步阐明对这些物质的时间和空间认识。关于PFAS，它们是由含氟调聚物醇（FTOHs）在长距离大气传输（LRAT）过程中氧化形成的，到达极地后通过湿沉降或干沉降而沉积。然而，对它们在北极的丰度和分布知之甚少。本项目旨在采集三个空间梯度上的雪样。首先，在东西梯度上，试图确定哪些气团可能是造成其LRAT的原因;其次，在纬度梯度上，以了解PFAS经历全球分馏的可能性;最后，将在不同的海拔高度上进行采样，以了解由于海拔高度引起的分馏。湖泊沉积物、雪坑和浅冰芯将在时间尺度上建立一个了解。这也应该提供一个洞察力，了解通过LRAT与当地居民点的污染源相比，该群岛受到PFAS污染的程度。将使用既定的方法提取和分析样本。对斯瓦尔巴特群岛沃茨中微塑料丰度和分布的了解很少，巴伦支海和北冰洋，后两个区域仅有单一研究。然而，值得注意的是，已经发现海冰中的微塑料比大西洋和太平洋的海洋环流高出几个数量级。因此，有人假设新海冰的形成可能会破坏这些微塑料。颗粒，集中在海冰中的微塑料。事实上，北冰洋可能是全球微塑料的主要汇。该项目旨在通过比较海冰核心和斯瓦尔巴特群岛周围的海水来进一步验证这一假设。此外，还将对海水和海冰进行测试，以了解斯瓦尔巴特群岛峡湾是否也是一个潜在的汇，以及当地污染源在污染这些沿海地区方面发挥了什么作用。将使用现有的方法分离和识别微塑料。这使得数据易于比较。虽然微塑料和PFAS的物理和化学性质几乎没有共同之处，这两种物质都是已知的有毒物质。希望通过进一步的监测，这些物质在斯瓦尔巴群岛的丰度和分布