Emerging and Legacy Contaminants in Soil and Water Systems: Pathways, Monitoring, Characterization, and Treatment

Dear Colleagues,

As essential environmental media and the material foundations for life on our planet, soil and water are vital components of Earth's natural systems. However, rapid industrialization and urbanization have introduced a diverse array of pollutants into these systems. Alongside legacy contaminants such as heavy metals and excess nutrients, urban environments are increasingly producing contaminants of increasing concern, including pharmaceuticals, microplastics, per- and polyfluoroalkyl substances (PFAS), pesticides, herbicides, endocrine-disrupting chemicals, personal care products, and tire-derived chemicals such as 6PPD and its transformation product 6PPD-Q. These pollutants are introduced through various sources and pathways, including discharge from wastewater treatment plants, surface water and stormwater runoff, and the land application of sludge/biosolids and compost. From these sources, contaminants can infiltrate into the subsurface and eventually reach groundwater systems. Over time, this continuum of transport may result in the contamination of drinking water supplies, posing serious risks to both ecological integrity and human health. 

This Special Issue aims to assemble cutting-edge research on both emerging and legacy contaminants across interconnected soil and water systems—including surface water, groundwater, wastewater, stormwater, and drinking water. Our goal is to present a comprehensive overview of contaminant pathways—from their sources and environmental transport to their monitoring and characterization, and innovative technological solutions for their treatment and remediation. 

We welcome high-quality original research articles and critical reviews focusing on, but not limited to, the following focus areas: 

1. Pathways and Transport:

• Studies on spatial and temporal distribution, as well as the accumulation of contaminants in soil and water systems.
• Identification of point and non-point sources contributing to contamination.
• Investigation of contaminant fate and transport processes, including mobility, persistence, and transfer across environmental media.

2. Monitoring:

• Development and application of field-based and real-time monitoring technologies for detecting contaminants.
• Integration of geospatial tools such as remote sensing, GIS, UAVs and GeoAI for mapping contamination hotspots and tracking pollutant transport.
• Use of sensor networks and automated systems to enable continuous, high-resolution monitoring

3. Characterization and Analysis:

• Target and non-target analyses using advanced instrumentation such as LC-HRMS to identify known and unknown contaminants.
• Investigation of contaminant speciation and bioavailability under different environmental conditions.

4. Treatment and Remediation:

• Evaluation and optimization of conventional and advanced treatment technologies, including adsorption, membrane filtration, photocatalysis, constructed wetlands, and bioreactors.
• Development of novel materials and engineered systems—such as functionalized sorbents, nanomaterials, photocatalytic compounds, and biosensors—for enhanced detection and removal of contaminants. 

We look forward to receiving your submissions to this Special Issue and advancing the collective understanding of emerging and legacy contaminants.

Dr. Jinsheng Huang
Prof. Dr. Yuchuan Fan
Dr. Xi Zhang
Guest Editors

Manuscript Submission Information

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