Terrestrial humic-like fluorescence peak of chromophoric dissolved organic matter as a new potential indicator tracing the antibiotics in typical polluted watershed

Sijia Li; Hanyu Ju; Meichen Ji; Jiquan Zhang; Kaishan Song; Peng Chen; Guangyi Mu

doi:10.1016/j.jenvman.2018.09.013

Terrestrial humic-like fluorescence peak of chromophoric dissolved organic matter as a new potential indicator tracing the antibiotics in typical polluted watershed

J Environ Manage. 2018 Dec 15:228:65-76. doi: 10.1016/j.jenvman.2018.09.013. Epub 2018 Sep 11.

Authors

Sijia Li¹, Hanyu Ju², Meichen Ji³, Jiquan Zhang⁴, Kaishan Song⁵, Peng Chen⁶, Guangyi Mu⁷

Affiliations

¹ School of Environment, Northeast Normal University, Changchun 130024, PR China. Electronic address: lisj983@nenu.edu.cn.
² School of Environment, Northeast Normal University, Changchun 130024, PR China. Electronic address: juhy287@nenu.edu.cn.
³ School of Environment, Northeast Normal University, Changchun 130024, PR China. Electronic address: jimc889@nenu.edu.cn.
⁴ School of Environment, Northeast Normal University, Changchun 130024, PR China. Electronic address: zhangjq022@nenu.edu.cn.
⁵ Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academic Science, Changchun 130102, PR China. Electronic address: songks@iga.ac.cn.
⁶ School of Tourism and Geography Sciences, Jilin Normal University, Siping 136000, PR China. Electronic address: pp11290@163.com.
⁷ Institute of Grass Science, Northeast Normal University, Changchun 130024, PR China. Electronic address: mugy390@nenu.edu.cn.

PMID: 30212676
DOI: 10.1016/j.jenvman.2018.09.013

Abstract

Natural surface waters are threatened globally by antibiotics pollution. In this study, we analyzed antibiotics and CDOM (Chromophoric dissolved organic matter) fluorescence in different water bodies using HPLC method and Excitation Emission Matrix- Parallel factor analysis, respectively. A combination of field studies in the Yinma River Watershed were conducted in rivers, reservoirs and urban rivers, and 65 CDOM and antibiotic samples were taken in April, May, July, and August 2016. EEM-PARAFAC analysis identified two components; a humic-like (C1) component and a tryptophan-like (C2) component. The redundancy analysis (RDA) demonstrated that CDOM could explain 38.2% (two axes) of the five antibiotics in reservoirs (N = 31), and 26.0% (two axes) of those in rivers and urban water (N = 30). Furthermore, the Pearson correlation coefficient between Sulfamethoxazole and C1 in reservoir water was 0.91 (t-test, 2-tailed, p < 0.01), and that between Sulfamethoxazole and C2 was 0.68 (t-test, 2-tailed, p < 0.01). This indicated that the humic-like component of CDOM PARAFAC fluorescence could detect Sulfamethoxazole contamination levels in the homogenized reservoir waters. Our results identified Sulfamethoxazole and Quinolones (Norfloxacin, 16.5 ng L^-1; Enrofloxacin, 0.3 ng L^-1; Ciprofloxacin, 30.9 ng L^-1) at mean concentrations of 369.5 ng L^-1 and 15.9 ng L^-1, respectively, which were the higher levels in natural surface waters. The FTIR spectroscopy of the mixture of humic acid and sulfamethoxazole showed that the absorbance at 3415 cm^-1 linked to OH stretching of OH groups and at 1386 cm^-1 because of OH bending and vibration of COOH groups became weaker, indicating that COOH groups of humic acid can adsorb and react with -NH₂ of sulfamethoxazole. The CDOM PARAFAC components can be adapted for online or in situ fluorescence measurements as an early warning of Sulfamethoxazole distribution and contamination in similar aquatic environments.

Keywords: Antibiotics; Chromophoric dissolved organic matter; PARAFAC; Polluted watershed; Sulfamethoxazole.

MeSH terms

Anti-Bacterial Agents / analysis*
Factor Analysis, Statistical
Fluorescence
Humic Substances / analysis
Rivers / chemistry*
Sulfamethoxazole / analysis
Water Pollutants, Chemical / analysis*

Substances

Anti-Bacterial Agents
Humic Substances
Water Pollutants, Chemical
Sulfamethoxazole