Work

Investigating pesticide contamination in arable soils: An advanced monitoring study from Northern Germany

Year: 2025

Type: article

Abstract: Pesticide contamination in agricultural soils remains a critical environmental issue due to the persistence and mobility of parent compounds and transformation products (TPs). Most studies have focused on surface soils and short-term dynamics, overlooking the long-term transport of pesticides in the subsurface. This study investigates spatiotemporal contamination patterns of applied and non-applied pesticides and their TPs across soil depths at two agricultural sites adjacent to lentic small water bodies (LSWBs) in Northern Germany. Over a 20-month period, monthly composite soil samples were collected at four depth intervals (0–90 cm) and analyzed for 25 pesticides and TPs. Two extraction solutions were applied to separate aliquots of the same soil sample: CaCl 2 to assess the mobile, bioavailable fraction, and MeOH to evaluate the sorbed fraction. The results revealed distinct contamination patterns among applied pesticides, TPs, and non-applied residues. Sorptive compounds such as diflufenican and tebuconazole accumulated in upper soil layers, while mobile TPs like metazachlor-ESA and flufenacet-ESA were detected in deeper horizons. Seasonal trends reflected application timing and precipitation dynamics, particularly in CaCl 2 extracts. Residues not applied during the monitoring period, including bixafen and metrafenone, were persistently detected, indicating legacy contamination and potential off-site inputs. The study underscores the importance of long-term and multi-depth monitoring approaches to capture the full extent of soil contamination. Differences between extractions highlight the need to assess immediate bioavailability and long-term storage in soils. These findings support the inclusion of TPs and deeper soil layers in monitoring frameworks to improve pesticide risk management and protect soil and groundwater.

Source: The Science of The Total Environment

DOI: 10.1016/j.scitotenv.2025.180378

Authors: Lukas P. Loose, Uta Ulrich, Nicola Fohrer

Institution: Christian-Albrechts-Universität zu Kiel

Language: English

Topic: Pesticide and Herbicide Environmental Studies

Subfield: Pollution

Field: Environmental Science

Domain: Physical Sciences

SDG: Life on land

Open Access status: hybrid

Estimated APC paid: $4,250