Collaborative Research: Predicting Current-Use Pesticides and Emerging Flame Retardants in a Changing Arctic - Fate and Phototransformation

北极正在经历快速的变化，如无冰季节的延长。在这一不断变化的景观中，必须解决的一个问题是最终进入北极的许多合成有机化学品的命运。人们对这些化学物质到达北极后的命运知之甚少，这些物质中的任何一种都可能伤害生物和人类。这些化合物的暴露风险与其环境命运紧密相关。这项研究将评估这些合成化合物的丰度以及北极环境分解这些物质的能力。为了支持未来科学家对这一新兴课题的教育，将为阿拉斯加夏季研究学院提供一个关于北极环境化学的高中模块。此外，Jennifer盖拉尔和Yu-Ping Chin的研究小组将为极地TREC（教师和研究人员探索和合作）计划招募一名教师。如果成功的话，这个项目将有助于指导快速发展的北极景观所需的污染物减排工作。最近在整个北极的苔原、空气、水、生物和人中发现了来自工业和农业的有机化学品。然而，人们对目前使用的农药（CUP）或新出现的溴化阻燃剂（EBFR）在北极的命运知之甚少。阿拉斯加大学费尔班克斯和特拉华州大学之间的这项合作旨在了解北极独特的环境如何影响CUP和EBFR的命运和转变。由于夏季连续的太阳辐照加上溶解有机物（DOM）的存在，光解可能在这些物质的命运中发挥关键作用。 这些因素可以通过与光衍生的活性氧（ROS）或其他途径反应来催化污染物衰减。本项目检验以下假设：1）在积雪融化期间和融化后不久，地表沃茨中的CUP和EBFR浓度将达到最高; 2）分析物-DOM复合物的形成将使这些物质更容易发生光降解。CUP毒死蜱和百菌清，和EBFR 1，2-双（2，4，6-三溴苯氧基）乙烷和四溴双酚A，将测量在两个领域的季节在图利克现场站的大气和水采样。将通过实地和实验室实验对悬浮固体、DOM和受北极DOM影响的光转化途径进行量化。将对物理和地球化学参数进行关键性测量，这些参数可纳入北极特有的化学归宿模型，包括用于划分环境分区的参数和光解途径的衰减率。将建立北极湖泊中CUP和EBFR的化学归宿模型，以预测在各种物理和环境条件下北极沃茨中的化学行为。量化这些化合物的持久性和转化对于北极地区污染物的风险评估和长期政策制定是必不可少的。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的知识价值和更广泛的影响审查标准进行评估来支持。

The Arctic is experiencing rapid changes such as longer ice-free seasons. One issue that must be navigated in this changing landscape is the fate of the many synthetic organic chemicals that ultimately end up in the Arctic. Little is known about the fate of these chemicals once they reach the Artic, and any of these substances can harm organisms and people. The exposure risk of these compounds is tightly coupled to their environmental fate. This research will assess the abundance of these synthetic compounds and the ability of the Arctic environment to break down these substances. To support the education of future scientists on this emerging topic, a high school module will be delivered for the Alaska Summer Research Academy on Arctic environmental chemistry. Additionally, the research groups of Jennifer Guerard and Yu-Ping Chin will recruit a teacher for the Polar TREC (Teachers and Researchers Exploring and Collaborating) Program. If successful, this project will help direct contaminant mitigation efforts that will be required in the rapidly evolving Artic landscape. Organic chemicals from industry and agriculture have been recently detected throughout the Arctic in the tundra, air, water, organisms, and people. However, little is known about the Artic fate of current use pesticides (CUPs) or emerging brominated flame retardants (EBFRs). This collaborative work between the University of Alaska Fairbanks and the University of Delaware seeks to understand how the Arctic's unique environment influences the fate and transformation of CUPs and EBFRs. Photolysis may play a critical role in the fate of these substances due to continuous solar irradiance in summer months coupled with the presence of dissolved organic matter (DOM). These factors can catalyze contaminant attenuation through reaction with photo-derived reactive oxygen species (ROS) or other pathways. This project tests the hypotheses that: 1) Concentrations of CUPs and EBFRs in surface waters will be highest during and immediately following melt of snowpack; and 2) The formation of analyte-DOM complexes will render these substances more susceptible to photodegradation. The CUPs chlorpyrifos and chlorothalonil, and EBFRs 1,2-bis(2,4,6- tribromophenoxy)ethane and tetrabromobisphenol A, will be measured by atmospheric and aqueous sampling over two field seasons at Toolik Field Station. Partitioning to suspended solids, DOM, and phototransformation pathways influenced by Arctic DOM will be quantified through field and laboratory experiments. Critical measurements will be made of physical and biogeochemical parameters that can be incorporated into an Arctic-specific chemical fate model, including parameters for partitioning into environmental compartments and attenuation rates by photolytic pathways. A chemical fate model for CUPs and EBFRs in Arctic lakes will be developed to predict chemical behavior in Arctic waters under various physical and environmental conditions. Quantifying the persistence and transformation of these compounds will be indispensable for risk assessment and long-term policy development for Arctic region contaminants.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.