Environmental drivers of monomethylmercury photodegradation along the land-to-ocean aquatic continuum.

IF 4.3 3区 环境科学与生态学 Q1 CHEMISTRY, ANALYTICAL
Sonja Gindorf, Johannes West, Andrew Graham, Sofi Jonsson
{"title":"Environmental drivers of monomethylmercury photodegradation along the land-to-ocean aquatic continuum.","authors":"Sonja Gindorf, Johannes West, Andrew Graham, Sofi Jonsson","doi":"10.1039/d4em00636d","DOIUrl":null,"url":null,"abstract":"<p><p>In surface waters, photodegradation is a major abiotic removal pathway of the neurotoxin monomethylmercury (MMHg), acting as a key control on the amounts of MMHg available for biological uptake. Different environmental factors can alter the rate of MMHg photodegradation. However, our understanding of how MMHg photodegradation pathways in complex matrixes along the land-to-ocean aquatic continuum respond to changes in salinity, dissolved organic carbon (DOC) concentration and dissolved organic matter (DOM) composition is incomplete. In a set of laboratory experiments combining several artificial and natural waters, we demonstrate that the interplay of DOC concentration, DOM composition, and salinity affects the photodegradation rate of MMHg. The presence of DOM was found to facilitate MMHg photodegradation, but degradation rates were not altered by varying DOC concentrations over two orders of magnitude. We found DOM composition to have a stronger effect on MMHg photodegradation rates than DOC concentration. However, at high DOC levels, where most UV radiation was lost within the first cm of the reaction vessels, lower MMHg photodegradation rates were observed. When moving from terrestrially influenced waters, characterized by a high degree of humification, towards marine conditions with a protein-rich DOM pool, MMHg photodegradation rates increased. In contrast, salinity had a stabilizing effect on MMHg. Hence, especially in systems with low salt and DOC concentrations, changes in either salinity or DOC concentration can impact the photodegradation rates of MMHg.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" ","pages":""},"PeriodicalIF":4.3000,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Environmental Science: Processes & Impacts","FirstCategoryId":"93","ListUrlMain":"https://doi.org/10.1039/d4em00636d","RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, ANALYTICAL","Score":null,"Total":0}
引用次数: 0

Abstract

In surface waters, photodegradation is a major abiotic removal pathway of the neurotoxin monomethylmercury (MMHg), acting as a key control on the amounts of MMHg available for biological uptake. Different environmental factors can alter the rate of MMHg photodegradation. However, our understanding of how MMHg photodegradation pathways in complex matrixes along the land-to-ocean aquatic continuum respond to changes in salinity, dissolved organic carbon (DOC) concentration and dissolved organic matter (DOM) composition is incomplete. In a set of laboratory experiments combining several artificial and natural waters, we demonstrate that the interplay of DOC concentration, DOM composition, and salinity affects the photodegradation rate of MMHg. The presence of DOM was found to facilitate MMHg photodegradation, but degradation rates were not altered by varying DOC concentrations over two orders of magnitude. We found DOM composition to have a stronger effect on MMHg photodegradation rates than DOC concentration. However, at high DOC levels, where most UV radiation was lost within the first cm of the reaction vessels, lower MMHg photodegradation rates were observed. When moving from terrestrially influenced waters, characterized by a high degree of humification, towards marine conditions with a protein-rich DOM pool, MMHg photodegradation rates increased. In contrast, salinity had a stabilizing effect on MMHg. Hence, especially in systems with low salt and DOC concentrations, changes in either salinity or DOC concentration can impact the photodegradation rates of MMHg.

求助全文
约1分钟内获得全文 求助全文
来源期刊
Environmental Science: Processes & Impacts
Environmental Science: Processes & Impacts CHEMISTRY, ANALYTICAL-ENVIRONMENTAL SCIENCES
CiteScore
9.50
自引率
3.60%
发文量
202
审稿时长
1 months
期刊介绍: Environmental Science: Processes & Impacts publishes high quality papers in all areas of the environmental chemical sciences, including chemistry of the air, water, soil and sediment. We welcome studies on the environmental fate and effects of anthropogenic and naturally occurring contaminants, both chemical and microbiological, as well as related natural element cycling processes.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信