Using HRMS fingerprinting to explore micropollutant contamination in soil and vegetables caused by swine wastewater irrigation

Wen-Ling Chen; Sih-Yi Yu; Shu-Yen Liu; Sheng-Chi Lin; Tsung-Han Lee

doi:10.1016/j.scitotenv.2022.160830

Using HRMS fingerprinting to explore micropollutant contamination in soil and vegetables caused by swine wastewater irrigation

Sci Total Environ. 2023 Mar 1:862:160830. doi: 10.1016/j.scitotenv.2022.160830. Epub 2022 Dec 13.

Authors

Wen-Ling Chen¹, Sih-Yi Yu², Shu-Yen Liu², Sheng-Chi Lin³, Tsung-Han Lee⁴

Affiliations

¹ Institute of Food Safety and Health, College of Public Health, National Taiwan University, Taiwan; Department of Public Health, College of Public Health, National Taiwan University, Taiwan; Department of Agricultural Chemistry, College of Bioresources and Agriculture, National Taiwan University, Taiwan. Electronic address: adelachen@ntu.edu.tw.
² Institute of Food Safety and Health, College of Public Health, National Taiwan University, Taiwan.
³ Hydrotech Research Institute, National Taiwan University, Taiwan.
⁴ National Taiwan University Plant Teaching Hospital, Taiwan.

PMID: 36526190
DOI: 10.1016/j.scitotenv.2022.160830

Abstract

Livestock wastewater has been reused for agricultural irrigation to save water and fertilise the soil. However, micropollutants excreted by livestock animals may contaminate the soil and crops through livestock wastewater irrigation. This study employed high-resolution mass spectrometry (HRMS) to facilitate broad-scope suspect screening of soil and vegetables and identify changes in micropollutant fingerprints caused by swine wastewater irrigation. Field trials were performed to simulate the practical cultivation of small leafy vegetables. Soil and pak choi were irrigated with groundwater, a reasonable amount of swine wastewater, and excessive swine wastewater (three times the reasonable amount) and were sampled at three time points. The samples were extracted using organic solvents and analysed with a liquid chromatography-quadrupole-time-of-flight HRMS system. The molecular features were compared to over 3000 micropollutants in commercial libraries. The relative concentrations of suspect micropollutants among the irrigation groups were compared using multivariate and univariate analyses. The marker micropollutants that increased with swine wastewater irrigation were rigorously identified based on the MS/MS spectra. Fifty-three micropollutants were frequently found in the soil (n = 54) and 36 in the pak choi (n = 53). Partial least squares discriminant analysis (PLS-DA) models revealed significant differences in the micropollutant fingerprints in the soil among the three irrigation groups, but not in the pak choi. Eight micropollutants with variable importance in projection scores above 1.0 in the PLS-DA model and significantly higher relative concentrations (p < 0.05) in the soil irrigated with swine wastewater were confirmed as markers. Besides veterinary drugs and their metabolites, cinnamic acid and phenylalanine were the markers relevant to swine feed that were not previously reported. Nevertheless, accumulations of micropollutants in the soil or contamination of the pak choi due to swine wastewater irrigation were not found under the trial conditions.

Keywords: Agricultural soil; Chemical fingerprinting; Field trial; Livestock wastewater irrigation; Micropollutant; Suspect screening.

MeSH terms

Agricultural Irrigation / methods
Animals
Livestock
Soil / chemistry
Soil Pollutants* / analysis
Swine
Tandem Mass Spectrometry
Vegetables
Wastewater*

Substances

Wastewater
Soil
Soil Pollutants