Collaborative Research: CBET: The role of sunlight in determining the fate and microbial impact of microplastics in surface waters

合作研究：CBET：阳光在决定地表水中微塑料的命运和微生物影响方面的作用

基本信息

批准号：
1911257
负责人：
Kara Law
金额：
$ 8.77万
依托单位：
Sea Education Association
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2019
资助国家：
美国
起止时间：
2019-08-01 至 2024-07-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1911257&HistoricalAwards=false
关键词：
Collaborative Research CBET role sunlight

项目摘要

Microplastics are plastic particles smaller than 5 mm in size. Microplastics mostly originate from fragmentation of larger plastic objects and are now found globally from drinking water to rivers, lakes and streams, and the oceans. An estimated 8 million tonnes of plastic waste enter the oceans from land each year, yet only a fraction of this material is accounted for by floating microplastics. One hypothesis for the missing microplastic is that exposure to sunlight degrades them to dissolved carbon. This project will assess whether sunlight-driven photochemical reactions release dissolved organic carbon from plastics, resulting in removal of the plastics from the water. A second objective of this project will test whether the chemicals released affect bacterial growth and survivability in natural waters. Results will improve our understanding of the fate of floating plastics in natural waters. This project will have significant broader impacts in the fields of environmental microbiology and photochemistry. Results will be incorporated into high school classroom learning geared towards middle and high school students, to increase the Nation's scientific literacy and educate the next generation of environmental engineers and scientists. In addition, the results will inform society on how to prioritize plastic waste management to protect human and ecological health. Microplastics are plastic particles smaller than 5 mm in size and originate from fragmentation of larger plastic objects released to the environment. Microplastics are found globally from drinking water to rivers, lakes and streams, and the oceans, where more than 98% of all buoyant microplastics are unaccounted for in loading estimates. The hypothesis for this research is that sunlight is responsible for degrading floating microplastics to dissolved organic carbon (DOC) on relatively short time scales (years). This hypothesis will be tested through a series of field, experimental, and analytical studies. The second hypothesis is that DOC released from photochemical breakdown will impact microbial growth. This hypothesis will be tested through bioassays with natural marine and freshwater microbes to assess the degradation kinetics (dissolution, fragmentation, and oxidation) of microplastics in seawater and freshwater in the light and dark, and with and without microbes. Experiments with plastics of variable polymer chemistry, size, and previous oxidation history will reveal the role of these factors in explaining variability in degradation rates to inform future modeling studies of plastic loss. The project brings together scientists with complementary educational, field, experimental, and analytical skills to transform our understanding of the fate and impact of buoyant microplastics in surface waters. Results will be disseminated to other scientists, the press, and incorporated into high school classroom learning via publication in the Science Journal for Kids, an open access journal which adapts primary, peer-reviewed research papers with age-appropriate language and illustrations geared towards middle and high school students.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.

微塑料是小于5 mm的塑料颗粒。微塑料主要源于较大塑料物体的碎片，现在从饮用水到河流，湖泊和溪流以及海洋的全球发现。估计每年有800万吨塑料废物从陆地进入海洋，但仅通过浮动微型塑料来解释这种材料的一小部分。缺失的微型塑料的一种假设是，暴露于阳光下会使它们降解以溶解碳。该项目将评估阳光驱动的光化学反应是否从塑料中释放出溶解有机碳，从而导致从水中清除塑料。该项目的第二个目标将测试释放的化学物质是否影响细菌生长和天然水域的生存能力。结果将提高我们对自然水域浮动塑料命运的理解。该项目将对环境微生物学和光化学领域产生更大的影响。结果将纳入针对中学生和高中生的高中课堂学习中，以提高美国的科学素养，并教育下一代环境工程师和科学家。此外，结果将为社会提供有关如何优先考虑塑料废物管理以保护人类和生态健康的情况。微塑料是尺寸小于5 mm的塑料颗粒，起源于释放到环境的较大塑料物体的碎片。从饮用水到河流，湖泊和溪流以及海洋，在全球范围内发现了微塑料，在那里，超过98％的所有浮力微塑料都无法估算。这项研究的假设是，阳光负责在相对较短的时间尺度（年）上降解浮动微塑料（DOC）。该假设将通过一系列领域，实验和分析研究进行检验。第二个假设是，从光化学分解中释放出的DOC将影响微生物的生长。该假设将通过天然海洋和淡水微生物的生物测定进行检验，以评估海水中的微塑料的降解动力学（溶解，碎片和氧化）在光明和黑暗中，以及和有没有微生物的降解动力学。可变聚合物化学，大小和以前的氧化历史的塑料实验将揭示这些因素在解释降解速率变异性中的作用，以告知未来的塑性损失模型研究。该项目通过互补的教育，领域，实验和分析技能汇集了科学家，以改变我们对浮力微塑料在地表水中的命运和影响的理解。结果将分解给其他科学家，新闻界，并通过《科学杂志》的儿童杂志（《开放访问》杂志的出版物纳入高中课堂学习，该杂志是一本开放式访问期刊，该期刊适应了由年龄符合年龄的语言和适合中学和高中生的插图的主要，同行评审的研究论文。该奖项反映了NSF的法定任务，反映了值得宽泛的范围，这是通过评估范围的范围。