Unveiling the effects of dissolved organic matter (DOM) extracted from coastal algae and river on the photooxidation of arsenite

被引：2

作者：

You, Tingting ^{[1
]}

Zhou, Mengchao ^{[1
]}

Ding, Yu ^{[1
]}

Yan, Zelong ^{[1
]}

Xi, Yimei ^{[2
]}

Yao, Shuhua ^{[3
]}

Zeng, Xiangfeng ^{[2
]}

Wang, Shaofeng ^{[1
]}

Jia, Yongfeng ^{[2
]}

机构：

[1] Dalian Univ Technol, Sch Environm Sci & Technol, Minist Educ, Key Lab Ind Ecol & Environm Engn, Dalian 116024, Peoples R China

[2] Chinese Acad Sci, Inst Appl Ecol, Key Lab Pollut Ecol & Environm Engn, Shenyang 110016, Peoples R China

[3] Shenyang Univ Chem Technol, Liaoning Engn Res Ctr Treatment & Recycling Indust, Shenyang 110142, Peoples R China

来源：

SCIENCE OF THE TOTAL ENVIRONMENT | 2024年 / 954卷

基金：

中国国家自然科学基金;

关键词：

Coastal algal dissolved organic matter; Riverine natural organic matter; Photooxidation; Arsenite; Excited triplet state dissolved organic matter; TRIPLET-STATE; AQUATIC PHOTOCHEMISTRY; SINGLET OXYGEN; HUMIC-ACID; OXIDATION; PHOTODEGRADATION; WATER; ARSENIC(III); ADSORPTION; KINETICS;

D O I：

10.1016/j.scitotenv.2024.176499

中图分类号：

X [环境科学、安全科学];

学科分类号：

08 ; 0830 ;

摘要：

The coastal environment is an important ecosystem connecting land and sea, and arsenite (As(III)) in coastal seawater can seriously affect human health through the food chain. However, the effects of dissolved organic matter (DOM) extracted from coastal algae and rivers on As(III) photooxidation remain unclear. Results show that coastal algal DOM (CA-DOM) is significantly more effective than Suwannee River natural organic matter (SRNOM) in photooxidation of As(III), with a rate 8.3 times higher after correcting for light screening effects. CA-DOM accelerates As(III) photooxidation mainly through the (DOM)-D-3* pathway, contributing 78.7% to the process, whereas (NOM)-N-3* contributes only 37.2 % for SRNOM. CA-DOM consists primarily of low-excited tyrosine and tryptophan-like protein substances, whereas SRNOM consists of humic and fulvic acid-like substances. Thus, CADOM exhibits a higher steady-state concentration of (DOM)-D-3*, and the (DOM)-D-3* reacts much faster with As(III) than the (NOM)-N-3*. The increase in CA-DOM concentration can significantly accelerate the photooxidation of As(III), whereas the effect of SRNOM concentration is negligible. Increased salinity can accelerate As(III) photooxidation for all types of DOM. Our results provide new insights into the role of DOM from different sources in the photooxidation of As(III) in the natural environment or engineering applications.

引用

页数：10