Hydrologic Analysis and Surface Water Sampling of Microplastics and PFAS Across Three Sites in the Mohawk River, New York

Catherine Ferry; Tasneem Tawalbeh; Virginia Smith; Erica Forgione; Kelly Good; Yuxin Wang

Our study investigated the co-contamination of microplastics (MPs) and per- and polyfluoroalkyl substances (PFAS) across three sites in the Mohawk River, New York. Conducted in collaboration with Villanova University and SUNY Binghamton, the research aimed to quantify and characterize MPs and assess their co-occurrence with PFAS under varying hydrologic conditions and watershed characteristics. Sampling of surface water was performed pre- and post-storm at Cohoes, NY (downstream of the Colonie Landfill), Rexford, NY (upstream of the Colonie Landfill), and Westernville, NY (in the Adirondack headwaters). Watershed analysis using ArcGIS revealed significant differences in drainage area and potential PFAS and MPs sources, with the Cohoes and Rexford sites exhibiting higher urbanization, road density, and point-source discharges compared to the Westernville site. The highly engineered nature of this barge-navigable waterway indicates that specific hydraulic conditions, such as dam backwater effects, may have reduced surface MP concentrations through settling and biofilm formation. Sample processing for MPs included filtration, acid and base digestions, and density separation, followed by visual microscopy and Raman spectroscopy for particle identification. Quality assurance measures included field, equipment, and laboratory blanks. The exploratory nature of this study, small sample volume , and procedural contamination complicated the MP analysis. This study highlights the complexity of MP fate and transport in engineered river systems and the difficulties in sampling and characterizing MPs and their co-contaminants. Final particle characterization and co-contaminant analysis results are expected to inform future watershed studies and pollution mitigation strategies.

Characterizing PFAS Contamination in Stormwater Outfalls, Milwaukee County, WI

Md Sakib; Walter McDonald

The frequency and spatial variability of per- and polyfluoroalkyl substances (PFAS) in stormwater outfalls remain poorly understood, even though they have become persistent contaminants of concern in urban environments. This study investigates PFAS distribution in stormwater discharges across Milwaukee County, Wisconsin, encompassing a range of land-use types. Stormwater samples from several outfalls were collected in both dry (baseflow) and wet (rainfall) conditions, and they were examined for 40 different types of PFAS compounds. Most samples had detectable PFAS concentrations with significant variation across land uses and hydrologic conditions. The results show that PFAS mass loads were frequently higher in wet-weather samples than in dry-weather samples, indicating increased mobilization during runoff events. Moreover, perfluoro butanoic acid, or PFBA, was the most common and predominant compound found at most sampling sites, ranging from 6.5 ng/L to 297 ng/L, frequently surpassing the levels of legacy PFAS, such as PFOS and PFOA. The observed temporal and spatial variability highlights how local infrastructure, storm dynamics, and land-use characteristics affect the pathways by which PFAS are transported. These findings contribute to our understanding of the presence of PFAS in urban stormwater and provide crucial information for future management of PFAS-contaminated runoff in urban drainage systems and the development of effective mitigation strategies.

Initiating Environmental Microplastics Research: Challenges in Data Collection, Management, and Analysis

Erica Forgione; Mikaela Oliver; Kelly Good

Recently, public interest in microplastics (MPs) has grown due to research indicating that they are ubiquitous and have the potential to cause large scale negative human and environmental health effects. However, MP analysis is still a developing area of research, resulting in laboratories expending significant effort to establish protocols for all parts of the process, including data collection, management, and analysis. Additionally, verification of quality data through Quality Assurance and Quality Control (QA/QC) remains difficult as standard protocols are still being developed. This presentation will overview the challenges associated with setting up a functional MP laboratory space for processing and analyzing environmental samples, from sample collection and storage to data analysis. Direct quantification and characterization of MP particles (for this research using visual microscopy and Raman spectroscopy) is time consuming and requires collecting large amounts of data and metadata for individual particles, which could number in the hundreds to thousands per sample. Data collection, management, and analysis will be focused on, including contamination reduction and QA/QC, spectral data collection and matching, and coding to merge visual microscopy and spectral datasets. This presentation aims to inform interested parties of the challenges associated with MP data collection and analysis based on insights gained by the authors as they initiated MP analysis for the first time.

Toward Standardized Microplastic Detection for Integrated Watershed and Aquatic Management

Mengshan Lee; Chichi Huang; Jing-Ru Chen

Microplastic pollution is an increasing global environmental challenge, with watersheds acting as major transport pathways delivering land-based plastics into aquatic and marine ecosystems. Microplastics serve as carriers for heavy metals and toxic compounds, and pose risks to ecosystem and human health. However, the absence of standardized analytical methods has limited data comparability and constrained effective watershed-scale pollution assessment. This study developed and validated a protocol for identifying microplastics in fish gastrointestinal tissues, with the aim of improving analytical reliability for watershed pollution monitoring. Five common plastic types (PP, PE, LLDPE, PLA, PHA) were subjected to pretreatment using fish intestinal tissue as an organic matrix. Digestion efficiency and plastic integrity were evaluated under varying digestion reagents, sample ratios, and digestion durations. Spectral integrity was assessed using ATR-FTIR, while surface morphology changes were examined via microscopy. Our results indicate that digestion with 30% hydrogen peroxide at room temperature for 96 hours effectively removed organic matter while preserving the chemical structure and morphology of all tested plastics. Compared to alkaline digestion, this method showed lower plastic degradation and higher recovery stability. Subsequent density separation using zinc chloride (1.63 g/cm³) and sequential glass fiber filtration (2.7 μm and 0.7 μm) enabled consistent and efficient microplastic recovery. Application of the standardized protocol to real fish samples confirmed its feasibility and reproducibility. The proposed method is low-cost, environmentally friendly, and operationally stable, making it suitable for routine laboratory analysis and field-based watershed monitoring. By improving data consistency and detection accuracy, this standardized approach enhances the assessment of microplastic contamination and supports science-based watershed management and pollution mitigation strategies.