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

由于《斯德哥尔摩公约》的影响，观察到斯瓦尔巴群岛的持久性有机污染物的生物趋势正在减少，从更广泛的意义上说，持久性有机污染物的来源、汇和运输的许多方面现在都得到了很好的了解。最初，持久性有机污染物被用作杀虫剂、工业化学品和工业副产品，但它们很快被证明在环境中无处不在。然而，自《斯德哥尔摩公约》批准以来，又发现了16种具有相同持久性、生物蓄积性和毒性的持久性持久性持久性化合物。因此，重要的是要尽早确定更多的潜在物质，并在空间和时间范围内了解它们，以便对它们进行监测。斯瓦尔巴群岛东部和西部的气候不同。由于急流带来温暖的海水和温和的天气，岛屿的西部气候较为温和。相反，东海岸接收来自北冰洋的冷空气和新鲜气流，气团通常来自欧亚大陆。由于群岛内存在不同的气候梯度，这使斯瓦尔巴群岛成为进入污染物运输途径的理想地点。北极监测评估方案概述了几种新出现的北极关注物质和化学品，它们具有类似持久性有机污染物的特性。在斯瓦尔巴群岛已查明并需要进一步注意的物种是多氟化烷基物质和微塑料。这个项目的目的是进一步阐明这些物质的时间和空间理解。就全氟磺酸而言，它们是由氟端聚体醇（FTOHs）在长距离大气运输（LRAT）过程中氧化形成的，到达极地后，它们以湿沉积或干沉积的方式沉积。然而，人们对它们在北极的数量和分布知之甚少。这个项目的目标是在三个空间梯度上采集雪样。首先，在东西向的梯度上，试图确定哪些气团可能负责它们的LRAT。其次，在纬度梯度上了解PFAS发生全球分馏的可能性。最后，采样将在不同的海拔进行，以获得由于海拔的分馏。希望这些研究的结果将有助于理解在时间尺度上取得的数据。湖泊沉积物，雪坑和浅冰芯将建立对时间尺度的理解。这也可以让我们了解到，与定居点的当地污染源相比，该群岛通过LRAT受到PFAS污染的程度。将使用既定的方法提取和分析样品。人们对斯瓦尔巴群岛水域、巴伦支海和北冰洋的微塑料丰度和分布知之甚少，对后两个地区只有单一的研究。然而，值得注意的是，在海冰中发现的微塑料比大西洋和太平洋环流高出几个数量级。因此，人们假设新海冰的形成可能会清除这些颗粒，将微塑料集中在海冰中。事实上，北冰洋可能是全球微塑料的主要储存库。该项目旨在通过比较斯瓦尔巴群岛周围的海冰核和海水，进一步验证这一假设。此外，还将对海水和海冰进行测试，以了解斯瓦尔巴群岛的峡湾是否也可以作为一个潜在的水槽，以及当地的污染源在污染这些沿海地区方面发挥了什么作用。微塑料将使用现有的方法进行分离和鉴定。这使得数据易于比较。虽然微塑料和PFAS在物理和化学性质上几乎没有共同点，但这两种物质都是有毒的。希望通过进一步监测，这些物质在斯瓦尔巴群岛的丰度和分布

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