Heavy metals trigger distinct molecular transformations in microplastic-versus natural-derived dissolved organic matter
Dissolved organic matter (DOM) is a key determinant of heavy metal fate in aquatic environments, influencing their mobility, toxicity, and bioavailability. Derived from natural sources such as soil and vegetation decomposition, natural DOM (N-DOM) typically features humic-like substances with abunda...
Saved in:
| Main Authors: | , , , , , , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Elsevier
2025-09-01
|
| Series: | Environmental Science and Ecotechnology |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S2666498425000882 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1849242814166073344 |
|---|---|
| author | Xianbao Zhong Kaiying Zhao Mengyuan Wu Yaohui Zhang Chiyue Ma Hexiang Liu Bokun Chang Xiaohui Lian Yujing Li Zixuan Huang Lang Zhu Ming Zhang Chi Zhang Yajun Yang Jialong Lv |
| author_facet | Xianbao Zhong Kaiying Zhao Mengyuan Wu Yaohui Zhang Chiyue Ma Hexiang Liu Bokun Chang Xiaohui Lian Yujing Li Zixuan Huang Lang Zhu Ming Zhang Chi Zhang Yajun Yang Jialong Lv |
| author_sort | Xianbao Zhong |
| collection | DOAJ |
| description | Dissolved organic matter (DOM) is a key determinant of heavy metal fate in aquatic environments, influencing their mobility, toxicity, and bioavailability. Derived from natural sources such as soil and vegetation decomposition, natural DOM (N-DOM) typically features humic-like substances with abundant oxygen-containing functional groups that stabilize heavy metals through complexation. However, microplastic-derived DOM (MP-DOM), increasingly prevalent due to plastic degradation, may interact differently with heavy metals, potentially exacerbating environmental risks amid rising plastic pollution. Yet, how heavy metals drive molecular transformations in MP-DOM versus N-DOM remains unclear, hindering accurate pollution assessments. Here, we compare interactions between N-DOM and MP-DOM with cadmium, chromium (Cr), copper, and lead from both fluorescence and molecular perspectives. Our results show that N-DOM, dominated by humic-like substances (46.0–57.3 %), lignin-like (55.0–64.9 %), and tannin-like (10.1–17.6 %) compounds, forms more stable heavy metal complexes via carboxyl, phenolic hydroxyl, and ether groups than MP-DOM. By contrast, MP-DOM—enriched in protein/phenolic-like substances (13.8–24.0 %), condensed aromatic (12.1–28.5 %), and protein/aliphatic-like (8.6–12.4 %) compounds—yields less stable complexes and is highly susceptible to Cr-induced oxidation. Mass-difference network analysis and density functional theory calculations further reveal that both DOM types undergo heavy-metal-triggered decarboxylation and dealkylation, but N-DOM retains complex structures, whereas MP-DOM degrades into smaller, hazardous molecules such as phenol and benzene. This study underscores the potential for heavy metals to exacerbate the ecological risks associated with the transformation of MP-DOM, providing crucial insights to inform global risk assessment and management strategies in contaminated waters where plastic and metal pollution co-occur. |
| format | Article |
| id | doaj-art-fa5bcdda82a049d081304ee40d612b46 |
| institution | Kabale University |
| issn | 2666-4984 |
| language | English |
| publishDate | 2025-09-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Environmental Science and Ecotechnology |
| spelling | doaj-art-fa5bcdda82a049d081304ee40d612b462025-08-20T03:59:41ZengElsevierEnvironmental Science and Ecotechnology2666-49842025-09-012710061010.1016/j.ese.2025.100610Heavy metals trigger distinct molecular transformations in microplastic-versus natural-derived dissolved organic matterXianbao Zhong0Kaiying Zhao1Mengyuan Wu2Yaohui Zhang3Chiyue Ma4Hexiang Liu5Bokun Chang6Xiaohui Lian7Yujing Li8Zixuan Huang9Lang Zhu10Ming Zhang11Chi Zhang12Yajun Yang13Jialong Lv14College of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, PR China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, Yangling, 712100, PR ChinaCollege of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, PR China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, Yangling, 712100, PR ChinaCollege of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, PR China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, Yangling, 712100, PR ChinaCollege of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, PR China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, Yangling, 712100, PR ChinaCollege of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, PR China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, Yangling, 712100, PR ChinaCollege of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, PR China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, Yangling, 712100, PR ChinaCollege of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, PR China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, Yangling, 712100, PR ChinaCollege of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, PR China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, Yangling, 712100, PR ChinaCollege of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, PR China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, Yangling, 712100, PR ChinaCollege of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, PR China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, Yangling, 712100, PR ChinaCollege of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, PR China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, Yangling, 712100, PR ChinaCollege of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, PR China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, Yangling, 712100, PR ChinaCollege of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, PR China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, Yangling, 712100, PR ChinaCollege of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, PR China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, Yangling, 712100, PR China; Corresponding author. College of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, PR China.College of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, PR China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, Yangling, 712100, PR China; Corresponding author. College of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, PR China.Dissolved organic matter (DOM) is a key determinant of heavy metal fate in aquatic environments, influencing their mobility, toxicity, and bioavailability. Derived from natural sources such as soil and vegetation decomposition, natural DOM (N-DOM) typically features humic-like substances with abundant oxygen-containing functional groups that stabilize heavy metals through complexation. However, microplastic-derived DOM (MP-DOM), increasingly prevalent due to plastic degradation, may interact differently with heavy metals, potentially exacerbating environmental risks amid rising plastic pollution. Yet, how heavy metals drive molecular transformations in MP-DOM versus N-DOM remains unclear, hindering accurate pollution assessments. Here, we compare interactions between N-DOM and MP-DOM with cadmium, chromium (Cr), copper, and lead from both fluorescence and molecular perspectives. Our results show that N-DOM, dominated by humic-like substances (46.0–57.3 %), lignin-like (55.0–64.9 %), and tannin-like (10.1–17.6 %) compounds, forms more stable heavy metal complexes via carboxyl, phenolic hydroxyl, and ether groups than MP-DOM. By contrast, MP-DOM—enriched in protein/phenolic-like substances (13.8–24.0 %), condensed aromatic (12.1–28.5 %), and protein/aliphatic-like (8.6–12.4 %) compounds—yields less stable complexes and is highly susceptible to Cr-induced oxidation. Mass-difference network analysis and density functional theory calculations further reveal that both DOM types undergo heavy-metal-triggered decarboxylation and dealkylation, but N-DOM retains complex structures, whereas MP-DOM degrades into smaller, hazardous molecules such as phenol and benzene. This study underscores the potential for heavy metals to exacerbate the ecological risks associated with the transformation of MP-DOM, providing crucial insights to inform global risk assessment and management strategies in contaminated waters where plastic and metal pollution co-occur.http://www.sciencedirect.com/science/article/pii/S2666498425000882Dissolved organic matterMicroplasticHeavy metalComplexationMolecular transformation |
| spellingShingle | Xianbao Zhong Kaiying Zhao Mengyuan Wu Yaohui Zhang Chiyue Ma Hexiang Liu Bokun Chang Xiaohui Lian Yujing Li Zixuan Huang Lang Zhu Ming Zhang Chi Zhang Yajun Yang Jialong Lv Heavy metals trigger distinct molecular transformations in microplastic-versus natural-derived dissolved organic matter Environmental Science and Ecotechnology Dissolved organic matter Microplastic Heavy metal Complexation Molecular transformation |
| title | Heavy metals trigger distinct molecular transformations in microplastic-versus natural-derived dissolved organic matter |
| title_full | Heavy metals trigger distinct molecular transformations in microplastic-versus natural-derived dissolved organic matter |
| title_fullStr | Heavy metals trigger distinct molecular transformations in microplastic-versus natural-derived dissolved organic matter |
| title_full_unstemmed | Heavy metals trigger distinct molecular transformations in microplastic-versus natural-derived dissolved organic matter |
| title_short | Heavy metals trigger distinct molecular transformations in microplastic-versus natural-derived dissolved organic matter |
| title_sort | heavy metals trigger distinct molecular transformations in microplastic versus natural derived dissolved organic matter |
| topic | Dissolved organic matter Microplastic Heavy metal Complexation Molecular transformation |
| url | http://www.sciencedirect.com/science/article/pii/S2666498425000882 |
| work_keys_str_mv | AT xianbaozhong heavymetalstriggerdistinctmoleculartransformationsinmicroplasticversusnaturalderiveddissolvedorganicmatter AT kaiyingzhao heavymetalstriggerdistinctmoleculartransformationsinmicroplasticversusnaturalderiveddissolvedorganicmatter AT mengyuanwu heavymetalstriggerdistinctmoleculartransformationsinmicroplasticversusnaturalderiveddissolvedorganicmatter AT yaohuizhang heavymetalstriggerdistinctmoleculartransformationsinmicroplasticversusnaturalderiveddissolvedorganicmatter AT chiyuema heavymetalstriggerdistinctmoleculartransformationsinmicroplasticversusnaturalderiveddissolvedorganicmatter AT hexiangliu heavymetalstriggerdistinctmoleculartransformationsinmicroplasticversusnaturalderiveddissolvedorganicmatter AT bokunchang heavymetalstriggerdistinctmoleculartransformationsinmicroplasticversusnaturalderiveddissolvedorganicmatter AT xiaohuilian heavymetalstriggerdistinctmoleculartransformationsinmicroplasticversusnaturalderiveddissolvedorganicmatter AT yujingli heavymetalstriggerdistinctmoleculartransformationsinmicroplasticversusnaturalderiveddissolvedorganicmatter AT zixuanhuang heavymetalstriggerdistinctmoleculartransformationsinmicroplasticversusnaturalderiveddissolvedorganicmatter AT langzhu heavymetalstriggerdistinctmoleculartransformationsinmicroplasticversusnaturalderiveddissolvedorganicmatter AT mingzhang heavymetalstriggerdistinctmoleculartransformationsinmicroplasticversusnaturalderiveddissolvedorganicmatter AT chizhang heavymetalstriggerdistinctmoleculartransformationsinmicroplasticversusnaturalderiveddissolvedorganicmatter AT yajunyang heavymetalstriggerdistinctmoleculartransformationsinmicroplasticversusnaturalderiveddissolvedorganicmatter AT jialonglv heavymetalstriggerdistinctmoleculartransformationsinmicroplasticversusnaturalderiveddissolvedorganicmatter |