Society of Environmental Toxicology and Chemistry

We are thrilled to announce that our upcoming spring meeting has garnered an exceptional response from professions and students across the region. The accepted abstracts cover a wide range of environmental and toxicological research topics. We look forward to exploring the insights and advancements they bring to the environmental science community.

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POSTER ABSTRACTS

Concentration Levels of Lead in Honey Brands from Supermarkets in Lancaster County, PA

Jada-Zara Agyare-Twum¹, Harriet Okatch², Andrew Huff², and Jeffrey Ashley¹

¹College of Life Sciences

²College of Population Health

Thomas Jefferson University, Philadelphia, PA

Abstract: 

Honey is a natural product widely consumed by humans and produced by bees that forage across large geographic areas. Because bees interact closely with their surrounding environment, honey can act as a bioindicator of environmental contamination, including the presence of heavy metals such as lead (Pb). Lead exposure is associated with serious health risks, particularly neurological and developmental effects in humans. Lancaster County, Pennsylvania has reported elevated lead exposure in local populations, highlighting the need to evaluate potential environmental sources of contamination. The objective of this study was to determine the concentration of lead in16 commercially available honey products sold in Lancaster County to assess potential human dietary exposure. Lead concentrations varied among the samples with concentrations ranging from below instrumental detection limits to 140 ppb (wet weight basis) with a mean of 50 ppb.  Overall, the lead concentrations detected in the analyzed honey samples were generally low and consistent with levels reported in previous studies worldwide. These findings suggest that the honey products analyzed do not currently indicate elevated lead contamination. Future studies should analyze a larger number of samples across multiple seasons and include raw honey sourced directly from local apiaries to better assess proximal environmental exposure pathways.

 

Nickel Uptake and Oxidative Stress Responses in Hydroponically Grown Vetiver Grass

Arash Aliasghar ¹, Rupali Datta ², and Dibyendu Sarkar ^1,*

¹  Department of Civil, Environmental and Ocean Engineering, Stevens Institute of Technology, Hoboken, NJ 07030, USA; aaliasg1@stevens.edu(AA); dsarkar@stevens.edu(DS)

²  Department of Biological Sciences, Michigan Technological University, Houghton, MI 49931, USA; rupdatta@mtu.edu

 

Abstract:

Urbanization, industrial processes, and mining activities contribute to the release of heavy metals such as nickel into wastewater, raising concerns for aquatic ecosystems and water quality. Nickel is a persistent metal contaminant that does not biodegrade and can exert toxic effects on plants, microorganisms, and aquatic organisms at elevated concentrations. Understanding the tolerance limits and physiological responses of plants to elevated metal concentrations is essential for evaluating their potential role in remediation systems.

This study evaluated the tolerance and nickel accumulation capacity of vetiver grass (Chrysopogon zizanioides), a perennial species widely investigated for phytoremediation. Plants were grown under controlled hydroponic conditions and exposed to five nickel concentrations: 0 (control), 20, 200, 400, and 1000 ppm, selected to evaluate plant tolerance and physiological responses across a wide range of nickel stress levels. Nickel accumulation in shoots and roots, together with plant physiological responses, was monitored over a 30-day exposure period.

Vetiver maintained normal growth and appearance at lower exposure levels (≤200 ppm) while demonstrating measurable nickel uptake. In contrast, plants exposed to higher concentrations (400–1000 ppm) exhibited visible stress responses, including chlorosis, reduced growth, and decreased biomass. These effects were accompanied by increased antioxidant enzyme activity, including superoxide dismutase (SOD), catalase (CAT), and glutathione S-transferase (GST), as well as elevated lipid peroxidation indicated by increased TBARS levels. Overall, the results provide insight into the nickel tolerance threshold of vetiver grass under hydroponic conditions and help clarify its physiological responses to elevated nickel stress, which is important for assessing its suitability for phytoremediation applications.

 

The Interactive Toxic Effects of Exposure to Persistent Organic Pollutants and Mercury on Early Life-Stages of Atlantic Tomcod

AUTHOR: Dorentina Gashi (graduate)

Abstract: 

Deleterious effects in young life-stages of fishes are often produced as an outcome of exposure of populations to singular or combined environmental pollutants from contaminated water bodies. Common responses to exposure in early life-stages of fishes include increased mortality, altered hatch rate, and morphological abnormalities. In this study, I conducted several exposure experiments to understand the difference of toxic responses to metals and persistent organic pollutants, individually and combined, on early life-stages of fishes. Adult Atlantic tomcod Microgadus tomcod were collected from the Hudson River and Downeast Maine populations and strip spawned in our collaborators' NOAA lab. The first 168-hour exposure subjected the two populations of Atlantic tomcod larvae to varying doses of mercury chloride (HgCl2) alone (0.01, 0.1, 1.0 ppm), 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) alone (0.1, 1.0 ppb); and four binary combinations of the listed doses. A follow up 168-hour exposure was conducted, which included a new dose of HgCl2 (0.5 ppm) individually and in-combination with 1.0 ppb TCDD. Larvae from the same adult populations were used, as well as an additional hybrid larvae group of these populations. The larvae that survived after both exposure periods were subsequently photographed for morphometric analysis. A final 60-hour exposure experiment was conducted a year later, where only the Hudson River population, at an embryonic stage, was exposed to TCDD (0.1, 1.0 ppb), HgCl2 (0.01, 0.05, 0.1, 0.5 ppm), and a single (0.1 ppm) concentration of an additional persistent organic pollutant, the polycyclic aromatic hydrocarbon (PAH) known as benzo(a)pyrene (BaP). Embryos were exposed to individual chemicals and to binary combinations of each persistent organic pollutant with HgCl2. Larvae from this experiment were consecutively pulled out after hatching for 1-day post-hatch and 10-day post-hatch imaging. Obvious synergistic or additive morphological, mortality, and hatch rate effects were not observed. Possible indications are chemical resistance or a higher-dosage threshold for the species. This study may also indicate molecular or genetic level toxicity whereas organismic changes were not necessarily a significant response to the chemical combinations. Further investigation is required to determine any correlation between chemical combinations with molecular and genetic toxicity, as well as to determine possible chemical resistance.

 

Freshwater Mussels as Biomonitors of Recovery following a Superfund Cleanup of a Large River

Professional

Authors: Sean Madden, Zoe Gliosco, Denise Meyer

Division of Fish & Wildlife

New York State Department of Environmental Conservation

 

Abstract:

Aquatic organisms are commonly used as biomonitors of polychlorinated biphenyls (PCBs) and other persistent contaminants in ecosystems. Native freshwater mussels (Family: Unionidae) are stationary organisms that filter particles from the water, are long-lived, and can be aged by counting external growth annuli, making them potential biomonitors of local contamination and ecosystem recovery. Recent Superfund remediation projects (e.g., Hudson River and Grasse River, NY) provide opportunities to study how native mussel communities respond to and recover from large-scale disturbances. As part of regular mussel surveys, we analyzed PCB concentrations in tissues from mussels that were collected between 2013 and 2023 from a series of four dam-defined river pools encompassing three river sections of the Hudson River. We also included samples from one pool upstream of the PCB contamination sources as a reference site. Three composite samples, each comprised of the tissues from five mussels, 75-80 mm in length, collected from unremediated areas within each pool were analyzed. As an indication of baseline PCB concentrations present prior to remedial activities, we extracted data from New York State’s fish contaminant database for unionid mussels in the same size range that were collected by GE in 2007, prior to the start of remedial activities in 2009. PCB concentrations in mussels decreased significantly from pre-dredge levels but are still 20-60 times greater than the last upstream reference. Our post-dredging data suggest that PCB concentration are higher in pools where less dredging occurred and exhibit an increasing trend with distance from the former plant sites. We plan to continue to collect mussels of the same size class (75-80 mm) on a 3-year cycle for PCB analysis to monitor long-term trends in PCB levels in mussels post-remediation as an indicator of environmental recovery.

 

PFAS Contamination in Absecon Bay, New Jersey

Daniel Jasinski¹, Thivanka Ariyarathna¹, Daehan Bong¹, Sara Nason², Priyankar Chand², Gustavo Garcia², Jasmine Jones², Mark Sullivan³

¹ Rowan University, Department of Environmental Science, 201 Mullica Hill Road, Glassboro, NJ 08028

² Connecticut Agricultural Experiment Station, 123 Huntington St, New Haven, CT 06511

³Stockton University, School of Natural Sciences and Mathematics, 101 Vera King Farris Drive

Galloway, NJ 08205

 

Abstract: 

Per- and polyfluoroalkyl substances (PFAS) are persistent environmental contaminants of emerging concern with incompletely characterized health impacts and exposure pathways. PFAS enter the environment through both point and non-point sources, yet comprehensive data on PFAS contamination in southern New Jersey’s coastal and estuarine environments remain limited. Absecon Bay is a coastal water body near Atlantic City that receives freshwater from Absecon Creek and stormwater via urban drainage pathways such as the Absecon Channel, which may transport PFAS and other urban contaminants into the bay. This study aimed to determine PFAS contamination in surface water, groundwater, sediment, and biota around Absecon Bay. Samples were collected during summer 2025 from sites inland within the bay and near the inlet connected to the open ocean, representing areas with distinct environmental characteristics. Biota samples encompassed four trophic levels from benthic and pelagic food webs, while water quality parameters and sediment characteristics were measured at each sampling location. Samples were processed and analyzed using ultra-performance liquid chromatography-mass spectrometry to quantify 19 PFAS compounds, including long- and short-chain perfluoroalkyl carboxylic acids and perfluoroalkyl sulfonic acids, encompassing legacy and emerging PFAS, using an adapted version of US-EPA Method 1633. Preliminary concentration data for surface water, groundwater, and biota (organism-specific PFAS concentrations) will be presented to characterize PFAS contamination in Absecon Bay. Estimated bioaccumulation factors will provide important information on PFAS bioaccumulation in economically important coastal species, while PFAS profiles in water will help identify contamination severity, supporting future risk evaluation for southern New Jersey coastal communities.

 

Synthesis and Evaluation of a TiO₂–Fir Biochar Composite for the Adsorption and Photocatalytic Degradation of PFOA and PFOS

 Parisa Javidan^1†,Sushma Yadav¹, Hadeer Saleh¹, Rupali Datta², Zhiming Zhang³, and Dibyendu Sarkar^1*  

¹Department of Civil, Environmental, and Ocean Engineering, Stevens Institute of Technology, Hoboken, NJ 07030, USA.  

²Department of Biological Sciences, Michigan Technological University, Houghton, MI 49931, USA. 

³Department of Civil and Environmental Engineering, Rowan University, Glassboro, NJ 08028, USA 

^†Graduate Student

^*Corresponding author email- dsarkar@stevens.edu

Abstract:

Per- and polyfluoroalkyl substances (PFAS) are a class of persistent environmental contaminants widely detected in water systems. Compounds such as Perfluorooctanoic acid (PFOA) and Perfluorooctanesulfonic acid (PFOS) are particularly concerning due to the strength of the carbon–fluorine (C–F) bond, which makes them highly resistant to conventional water treatment processes. This study investigated the removal and degradation of PFAS using a TiO₂-Fir biochar composite synthesized through a sol-gel method followed by pyrolysis. The composite integrates the high adsorption capacity of biochar with the photocatalytic properties of TiO₂, creating a dual-function material capable of both capturing and degrading PFAS.

Batch adsorption experiments were conducted to evaluate the removal performance of the composite toward PFOA and PFOS. Kinetic modeling indicated that the adsorption process follows a pseudo-second-order model, suggesting that chemisorption and surface interactions play a dominant role in PFAS uptake. The TiO₂-Fir biochar composite demonstrated a strong affinity for PFAS compounds, enabling rapid adsorption prior to photocatalytic treatment. Subsequent photocatalytic experiments were performed under UV irradiation to evaluate PFAS degradation. Complete degradation of PFOS was achieved within 10 minutes with no detectable transformation byproducts. In comparison, PFOA degradation reached approximately 99% after 3 hours of irradiation, with only trace amounts of Perfluorohexanoic acid (0.061 ppb) detected as a potential byproduct. Ion chromatography confirmed the release of fluoride ions, indicating C–F bond cleavage and successful defluorination during treatment.

Overall, the TiO₂–Fir biochar composite demonstrated a promising combination of adsorption-photocatalytic degradation for PFAS remediation, providing an effective and potentially scalable approach for the treatment of PFAS-contaminated water systems.

Keyword: Perfluorooctanoic acid, Perfluorooctanesulfonic acid, TiO₂–biochar composite, Photocatalytic degradation, Adsorption

Assessing Commercial Sorbents as Permeable Reactive Barrier Media for Treatment of PFAS, 1,4-Dioxane, and Metals-Contaminated Groundwater

Sevda Joudiazar¹, Zhiming Zhang², Junchul Kim³, Rupali Datta⁴, and Dibyendu Sarkar¹

¹Department of Civil, Environmental and Ocean Engineering, Stevens Institute of Technology, Hoboken, NJ 07030, USA

²Department of Civil and Environmental Engineering, Rowan University, Glassboro, NJ 08028, USA

³Tetra Tech, Inc., King of Pasadena, PA 19406, USA

⁴Department of Biological Sciences, Michigan Technological University, Houghton, MI 49931, USA

Abstract: 

Per- and polyfluoroalkyl substances (PFAS) are commonly detected in contaminated groundwater together with heavy metals and other organic pollutants; however, effective methods for their simultaneous treatment are not yet fully understood. This work investigated the performance of two commercially available sorbent materials, Filtrasorb 400 (FS-400) and zero-valent iron (ZVI), for the co-removal of multiple contaminants. The study focused on three PFAS compounds, perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), and perfluorononanoic acid (PFNA), along with the arsenic, cobalt, and 1,4-dioxane present in contaminated groundwater. Continuous-flow column tests were conducted using two media configurations: a column packed solely with FS-400 and another packed with a mixture of FS-400 and ZVI (FS-400+ZVI). During the initial operation period of up to 100 bed volumes (BV), both configurations showed comparable PFAS and 1,4-dioxane removal efficiencies, ranging between approximately 80% and 85%. In contrast, the combined FS-400+ZVI system demonstrated notably greater effectiveness in removing metal contaminants compared with the FS-400 column alone. A breakthrough occurred between approximately 50 and 150 BV for the PFAS compounds, 100 BV for 1,4-dioxane, and 50 BV for metal ions. Overall, the findings indicate that FS-400 provides effective PFAS and 1,4-dioxane removal in the early operational phase, whereas incorporating ZVI enhances the capture of heavy metals, suggesting that hybrid media systems may offer advantages for the treatment of groundwater impacted by multiple contaminants.

Competitive Sorption of Metals onto Modified Biochar in the Presence of Microplastics

Graduate Student Poster

Authors: Bobby Leary, Erica McKenzie

 

Abstract: 

Urban stormwater runoff is a major pathway for metals and microplastics to enter aquatic ecosystems, posing risks to water quality and ecological health. Stormwater runoff is captured by bioretention systems amended with biochar, which are increasingly used to mitigate metal contamination through sorption processes. The influence of microplastics on metal removal in these systems is not well understood, however. This study investigates the competitive sorption behavior of multiple metals (Fe, Cu, Cr, Cd, and Ni) onto unmodified and modified biochar in the presence of aged polypropylene microplastics under environmentally relevant conditions.

Wood-derived biochar was modified using potassium hydroxide (KOH) to increase surface area and ferric chloride (FeCl₃) to change surface functional groups. Microplastics were aged under natural sunlight to simulate environmental weathering. Batch equilibrium experiments were conducted in synthetic stormwater to quantify metal sorption onto biochar and microplastics. Isotherm analyses, where sorbate concentrations are varied, were performed to determine sorption capacities. The effects of pH and dissolved organic matter (DOM) on metal sorption were also evaluated. Sorbent surface characteristics were assessed using FTIR, and dissolved and sorbed metal concentrations were measured by ICP-MS.

Results are expected to demonstrate that microplastics reduce the sorption capacity of biochar through competition for binding sites and pore blocking by leached DOM, leading to increased dissolved metal fractions. Modified biochars are anticipated to mitigate these effects, though performance may decline under acidic and high-DOM conditions. This work provides insight into the interactive effects of emerging and regulated contaminants in stormwater treatment systems.

 

Preliminary Assessment of Lead in Dried Herbs from Online and Market Sources

Lisa B. Lomax, JoanR. Dischert, Harriet Okatch, Andrew Huff  and Jeffrey Ashley

College of Life Sciences

Thomas Jefferson University, Philadelphia, PA

 

Abstract:

Lead contamination in food products remains a public health concern due to itscumulative toxicity and lack of safe exposure thresholds. Although consumed in small quantities, dried herbs may contribute to chronic dietary lead exposure. This study assessed lead (Pb) concentrations in commercially available dried herbs from online and market sources. Samples were homogenized, digested, and analyzed using graphite furnace atomic absorption spectroscopy (GFAAS) to quantify Pb levels and assess variability among products. Lead concentrations ranged from 0.111 to 2.294 µg/g, with rosemary exhibiting the highest average concentrations (1.315 ± 0.574 µg/g, n=9), while other herbs—basil, parsley, marjoram, cilantro, and thyme—generally averaged below 0.7 µg /g.  These data will provide preliminary insight into the presence of lead in commonly consumed herbs and contribute to understanding potential dietary exposure from these products.

 

 

 

 

STUDENT (GRADUATE)

Reuse of Drinking Water Treatment Residuals for Stabilizing PFAS in Biosolids

Khalid Mustafa¹, Anirban Dhulia², Zhiming Zhang³, Michel C. Boufadel²,Rupali Datta⁴, Dibyendu Sarkar¹

¹Department of Civil, Environmental and Ocean Engineering, Stevens Institute of Technology, Hoboken, NJ 07030, USA

²Center for Natural Resources, Department of Civil and Environmental Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA

³Department of Civil and Environmental Engineering, Rowan University, Glassboro, NJ 08028, USA

⁴Department of Biological Science, Michigan Technological University, MI 49931, USA

 

Abstract: 

Biosolids are widely applied in agriculture as a cost-effective, nutrient-rich fertilizer. However, they may also serve as a significant pathway for the introduction of per- and polyfluoroalkyl substances (PFAS) into agricultural environments, raising concerns about long-term accumulation in soils, contamination of groundwater, and uptake by crops. This study investigated a cost-effective stabilization approach to reduce PFAS mobility in biosolids via amendment with drinking water treatment residuals (DWTRs). DWTRs are aluminum- and/or iron-rich solid wastes generated during coagulation in drinking water treatment process. Their high specific surface area and abundant surface functional groups make them promising sorbent materials. Two DWTRs, generated using polyaluminum chloride (PAC-WTR) and aluminum sulfate (AL-WTR) as coagulants were evaluated as repurposed sorbent amendments and compared with a commercial adsorbent, granular activated carbon (GAC 400), for PFAS immobilization in two distinct biosolids: one originating from a mix of residential and industrial sources and another from residential wastewater. Biosolids were amended at 2.5%, 5%, 10%, and 20% (w/w) rates and incubated for 30 days. PFAS immobilization effectiveness was evaluated on days 1, 7, and 30 using water leachate (WL), toxicity characteristic leaching procedure (TCLP), and methanol leachate (ML). WL simulated environmental conditions, TCLP represented regulatory scenarios, and ML estimated maximum releasable PFAS. PFAS mobility consistently decreased with increasing curing time. The effectiveness followed the order AL-WTR (10%) ≥ GAC 400 (10%) > PAC-WTR (10%). AL-WTR exhibited the most stable reduction of WL and TCLP extractable PFAS, whereas short-chain PFAS remained comparatively mobile. Overall, the repurposing of WTRs represents a practical, low-cost circular-economy solution for limiting PFAS release from biosolids and reducing environmental transport risks.

 

 

Abstract Title: Liquid chromatography method development for quantitative assessment of Per  and polyfluoroalkyl substances in different sample matrices

Authors: Oluwafemi Benjamin Omidele, Erica Mckenzie

 

Abstract: 

Per‑ and polyfluoroalkyl substances (PFAS) are persistent synthetic compounds that have been observed to be bioaccumulative and toxic, which is quantified in an ultra-trace scale to meet regulatory limits (mostly ≤ 1 ng L⁻¹). Due to their high polarity and ionic nature, some chromatography techniques are not suitable for quantitative measurement of PFAS across different matrices. Liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (LC/QTOF/MS) remains the most reliable PFAS analysis method due to its sensitivity, selectivity, and simultaneous detection of multiple PFAS compounds. In this study, we describe the development and validation of an LC method optimized for the measurement of 40 PFAS compounds in aqueous, solid (soil), and tissue (vegetables, e.g., lettuce, tomato, and carrot) matrices. We optimized the column chemistry, mobile phase composition, and gradient program to avoid coelution of our PFAS, improve peak shape and chromatographic resolution, and reduce matrix-induced ion suppression. For method validation and performance, we will base our assessment on 70-130% recoveries of our PFAS and EIS (extraction internal standard), and a relative standard deviation of ≤20%. These validated procedures meet the criteria established in EPA Method 1633 and provide a reliable and scalable approach to the routine monitoring of PFAS in laboratories associated with the environment and food safety.

 

Identifying distinct PFAS patterns in New Jersey soil and potential drivers using machine-learning methods

Emma Rosenheim¹ and Skyler Sorsby¹

¹WSP USA, Inc., Marlton, NJ, USA

* Correspondence: Emma.Rosenheim@wsp.com

Abstract: 

PFAS (Per- and Polyfluoroalkyl Substances) are emerging contaminants of concern, ubiquitous in New Jersey surficial soils [1]. Understanding the spatial distribution of PFAS is necessary to support proper regulation. While regional ambient concentrations have recently been quantified by NJDEP, systematic variations of chemical profiles and potential drivers for those differences are not well understood. Here we use a novel combination of unsupervised and supervised machine learning to identify distinct PFAS patterns in NJDEP’s regional soils dataset. We explore spatial variability and perform advanced correlations to determine potential drivers for each pattern. Nine distinct patterns predominated, including PFOA-, PFOS-, and PFBA-dominated profiles in North/Central Jersey, PFUnA-, PFNA-, and GenX-dominated profiles in Central/South Jersey, and PFOS-dominated profiles along the coast. Advanced correlation performed with nonlinear ensemble machine learning (random forest) and explainable AI (SHAP) indicates that the likely deposition mechanism varies between wet and dry deposition, and that proximal cultivated land, fluvial inundation, and basin-scale erosion rates may influence profiles in some areas. These findings help to promote a greater understanding of PFAS distribution through the extraction of key patterns from complex chemistry datasets, revealing clear differences and distilling the presence of those patterns into few, easily-visualized variables. This clarity is necessary when assessing ambient PFAS occurrence in different regions of the state.

• 1.     Willemsen, Jennifer, et al. “Per- and Polyfluoroalkyl Substances in New Jersey Soils: A Statewide Investigation.” New Jersey Department of Environmental Protection, Contaminated Site Remediation and Redevelopment, Sept. 2025.

In-situ Stormwater Treatment Using Green Engineered Mulch (GEM): Field Performance of a GEM-Retrofitted Urban Rain Garden

 

Hadeer Saleh,¹ Rupali Datta², and Dibyendu Sarkar ¹

¹Department of Civil, Environmental and Ocean Engineering, Stevens Institute of Technology, Hoboken, NJ 07030, US

²Department of Biological Sciences, Michigan Technological University, Houghton, MI 49931

 

Abstract: 

Urban stormwater runoff contains a mixture of contaminants, including nutrients (oxyanions, such as phosphate), metals, and emerging contaminants, such as per- and polyfluoroalkyl substances (PFAS), that are not effectively removed by conventional green infrastructures (GIs). This study evaluates Green Engineered Mulch (GEM), a patent-pending stormwater filtration media designed to enhancein-situ pollutant removal in GIs. GEM consists of wood mulch coated with aluminum-based water treatment residuals (Al-WTR), a non-hazardous industrial solid waste generated during the coagulation phase of drinking water treatment process using Al salts. It is typically composed of organic carbon and amorphous aluminum (hydr)oxides with high surface area and strong sorption capacity for metals, oxyanions, and PFAS.

Field performance of GEM was assessed in two roadside municipal rain gardens in Secaucus, New Jersey: a conventional system (control) and a GEM-retrofitted system (treatment) located across from each other along one of the busiest town thoroughfares experiencing high vehicular activities. Ten storm events were monitored between August 2023 and July 2024, including five baseline and five post-retrofit events. Stormwater samples were collected at inflow, leachate, and outflow locations to evaluate pollutant attenuation during infiltration.

Baseline results showed limited treatment efficiency, with ~11% removal of total suspended solids (TSS), 13–20% for phosphorus, and <5% for nitrogen species, while metals ranged from 0.9–45%. Following GEM installation, removal efficiencies increased to ~50% for TSS, 44–50% for phosphorus, and 17–70% for metals. Nitrogen removal improved modestly (6–14%). PFAS analysis showed no attenuation in the control system, with ΣPFAS ranging between1300–1700 ppt. In contrast, the GEM-retrofitted system achieved 19–22% removal of total PFAS, with higher removal of long-chain PFAS, including PFOA (38–47%) and PFOS (42–48%).

These results demonstrate that GEM is a scalable, field-ready strategy for improving stormwater treatment in-situ, particularly for long-chain PFAS and legacy contaminants.

 

Dual-Phase Assessment of Fluridone: Detection by Fluorescence Spectroscopy and Degradation by Conventional Water Disinfection Methods

Author: Mahnoor S. Sultan

Author Affiliation: Student – Undergraduate – Manhattan University

 

Abstract: 

This study addresses the dual challenges of detecting and removing the herbicide fluridone from drinking water. First, we evaluate fluorescence spectroscopy and the ELISA method as rapid, cost-effective alternatives to traditional methods like using the HPLC for herbicide quantification. Laboratory analysis of fluridone and a second herbicide, florpyrauxifen-benzyl, using fluorescence spectroscopy demonstrated strong linear correlations between fluorescence intensity and concentration (R² > 0.97), with a detection limit of approximately 10 ppb. The method was reproducible and showed strong agreement with ELISA, confirming its reliability for fast concentration monitoring.

Given its use in reservoirs in the New York State Water Supply System, we then investigated the efficacy of standard drinking water disinfection processes in degrading fluridone. Experiments using ultraviolet (UV) irradiation (20–40 mJ/cm²) and chlorination (2 mg/L) were conducted, with fluridone concentrations quantified via both ELISA and the validated fluorescence method. Results indicated that both UV and chlorination achieve partial, concentration-dependent degradation of fluridone, with greater removal observed at lower, environmentally relevant concentrations (e.g., 30-40% removal at 10 μg/L). However, varying the UV dose or chlorine contact time had minimal effect on removal efficiency.

Collectively, these findings establish fluorescence spectroscopy as a viable tool for rapid herbicide detection and reveal that conventional disinfection practices only partially remove fluridone, highlighting a need for optimized treatment strategies to ensure public health protection. Our research is currently ongoing with the intention of continuing testing the efficacy of disinfection methods and validate and reproduce our fluorescence spectroscopy results with the HPLC method.

 

Hydrothermal transformation of microplastics in subcritical water

 

Authors:

Shirui Zhang (presenter),^a Charlotte Orton,^b Margaret Wisneski,^a Aili Kelley,^c Jenny Cruz,^d Georgia Arbuckle-Keil,^e Nicole Fahrenfeld,^a Yalin Li^a

^aDepartment of Civil and Environmental Engineering, Rutgers-New Brunswick.

^bDepartment of Chemistry, Rutgers-New Brunswick.

^cDepartment of Chemical and Biochemical Engineering, Rutgers-New Brunswick.

^dDepartment of Environmental Sciences, Rutgers-New Brunswick.

^eDepartment of Chemistry, Rutgers-Camden.

 

Keywords:

Hydrothermal processing; Microplastics; polyethylene (PE); polyethylene terephthalate (PET); polyvinyl chloride (PVC)

 

Abstract:

Increasing concerns about microplastics in organic waste have been raised due to potential impacts on ecosystems and human health. As waste collection and treatment systems are not designed to remove or destroy microplastics, these particles can accumulate in organic waste streams such as food waste and wastewater treatment sludge. When waste-derived products (e.g., compost, biosolids) are subsequently applied to land, microplastics may be reintroduced into the environment. Hydrothermal processes, an emerging technology under elevated temperature and pressure for organic waste valorization, offer a potential solution. Recent studies suggest that these processes can effectively degrade certain types of plastics while simultaneously enabling the valorization of organic waste. In this presentation, polyethylene (PE), polyethylene terephthalate (PET), and polyvinyl chloride (PVC) microplastics of different sizes (<0.5 mm vs. 3 mm) were subjected to hydrothermal treatment at temperatures of 250°C and 350°C for 30 and 120 minutes, with loadings of 1% and 10%. The transformation of microplastics was evaluated through mass loss measurements and morphological characterization. The major components in the post-reaction aqueous phase were analyzed. Pre-treatment plastics and post-treatment solid residues were examined using attenuated total reflectance Fourier-transform infrared (ATR-FTIR) spectroscopy to better understand the transformation of microplastics. The results showed that mass loss increased significantly with increasing temperature and reaction time, indicating enhanced degradation under more severe hydrothermal conditions for all three types of microplastics (PE, PET, and PVC). Morphological analysis showed pore formation and structural collapse on particle surfaces after reaction, particularly at 350°C. For PVC, the chloride concentration normalized by mass loss was primarily affected by temperature. This study provides insights into the transformation pathways of PE, PET, and PVC microplastics under hydrothermal conditions and highlights the potential of hydrothermal processes for the treatment and valorization of microplastic-laden waste streams.