Work

Determining the binding of heavy metals, biocides, and their transformation products with dissolved organic matter – Understanding pollutants interactions in building façade runoff

Year: 2025

Type: article

Abstract: Understanding the interaction between biocides and heavy metals with dissolved organic matter (DOM) is the basis of building runoff treatment facility development. In the present study, we aimed to quantitatively determine the binding of biocides/heavy metals with DOM and evaluate the effect of Cu 2 + on biocides-DOM interaction. We hypothesize that biocides prefer to bind with DOM having a larger molecular weight (MW), and this binding can be inhibited by Cu 2+ . In experiments, DOM was separated into different fractions according to their MW difference, then we investigated the binding of Cu 2+ , Zn 2+ , biocides, and their transformation products (TPs) to different DOM fractions by dialysis equilibrium. According to the results, Cu 2+ was found having the highest affinity for DOM fraction > 100 kDa with the mean binding value of 2.65 μmol/mgC, which reduced with decreasing DOM MW. Zn 2+ binding to DOM was much weaker than Cu 2+ with a mean value below 0.296 μmol/mgC and Zn 2+ did not show a clear preference for DOM MW. Parent biocides showed higher DOM affinity than their TPs. The binding affinity of biocides to DOM followed the order mecoprop-p > terbutryn > diuron. Hydrogen bonding was found to play an important role in biocides-DOM binding. Moreover, the opposite effect of Cu 2+ on biocides-DOM binding was observed, with inhibition for DOM fractions> 100 kDa and enhancement for DOM fractions < 100 kDa. Our findings suggest that source control of biocides/TPs pollution is important because a relatively high mobility of biocides/TPs in the environment is expected due to their limited interaction with DOM. • The co-presence of metals, biocides, and DOM in building runoff is investigated. • Cu 2+ -DOM binding was positively related to DOM molecular weight. • Parent biocides had higher DOM binding capability than their transformation products. • Hydrogen bonding played an essential role in biocides-DOM binding. • Opposite effects of Cu 2+ were found in biocides binding to different DOM fractions.

Source: Ecotoxicology and Environmental Safety

DOI: 10.1016/j.ecoenv.2025.117887

Authors: Panfeng Zhu, Ignacio Sottorff, Jianyuan Bi, Brigitte Helmreich

Institution: Technical University of Munich

Language: English

Topic: Pharmaceutical and Antibiotic Environmental Impacts

Subfield: Pollution

Field: Environmental Science

Domain: Physical Sciences

SDG: Clean water and sanitation

Open Access status: gold

Estimated APC paid: $3,650