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SFS Annual Meeting

Wednesday, June 5, 2024
13:30 - 15:00

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S04 Contaminant Ecology of Freshwaters

13:30 - 13:45 | Freedom Ballroom F | FISH PRESENCE IN HUMAN-MADE PONDS INFLUENCES INSECT-MEDIATED MEHG FLUX

6/05/2024  |   13:30 - 13:45   |  Freedom Ballroom F

FISH PRESENCE IN HUMAN-MADE PONDS INFLUENCES INSECT-MEDIATED MEHG FLUX When adult aquatic insects emerge from waterbodies, they transport methylmercury (MeHg) produced in aquatic systems to terrestrial predators. This “insect-mediated MeHg flux” from pond systems may be an important source of MeHg to terrestrial food webs in the U.S. Great Plains, where there are millions of human-made ponds. The present study tested the hypothesis that the presence of fish would suppress insect emergence of large insects (e.g., odonates) and, therefore, decrease insect-mediated MeHg flux compared to fishless ponds. Emerging aquatic insects were collected using floating emergence traps from 4 ponds with fish, and 7 fishless ponds at the LBJ National Grasslands, TX (southern Great Plains of the U.S.) from March to July, 2018. We calculated MeHg flux for each insect taxa as insect biomass x MeHg concentration/m2/day. Mean (±SE) MeHg flux was ~10x higher from fishless ponds than ponds with fish at 2.94 (±0.27) and 0.26 (±0.08) ng/m2/day, respectively (ANOVA p<0.001). Significantly more insects emerged from fishless ponds (ANOVA p=0.03), especially odonates (dragonflies and damselflies). In fishless ponds, odonates made up the majority of MeHg flux (67%, 2 ng/m2/day), whereas small flies (midges) dominated MeHg flux in ponds with fish (61%, 0.2 ng/m2/day). This study suggests that pond community structure can influence aquatic insect emergence and cross-system transport of contaminants from ponds to terrestrial food webs. Although fishless human-made ponds could provide more emergent insect prey for native terrestrial species, they could also transport more MeHg to terrestrial consumers compared to ponds with fish.

Maddy Hannappel (Primary Presenter/Author), California Academy of Sciences, mphannappel@gmail.com;

Matthew Chumchal (Co-Presenter/Co-Author), Texas Christian University, m.m.chumchal@tcu.edu;

Ray Drenner (Co-Presenter/Co-Author), Texas Christian University, r.drenner@tcu.edu;

James Kennedy (Co-Presenter/Co-Author), University of North Texas, james.kennedy@unt.edu;

Lexi Freeman (Co-Presenter/Co-Author), Texas Christian University, l.r.freeman@tcu.edu;

Benjamin Barst (Co-Presenter/Co-Author), University of Alaska, Fairbanks, bdbarst@alaska.edu;

13:45 - 14:00 | Freedom Ballroom F | BIOACCUMULATION AND TRANSFER OF PER- AND POLYFLUOROALKYL COMPOUNDS IN A CONTAMINATED STREAM FOOD WEB

6/05/2024  |   13:45 - 14:00   |  Freedom Ballroom F

BIOACCUMULATION AND TRANSFER OF PER- AND POLYFLUOROALKYL COMPOUNDS IN A CONTAMINATED STREAM FOOD WEB Per- and polyfluoroalkyl substances (PFAS) in freshwater ecosystems are a global concern due to their persistent and bioaccumulative nature and potential toxicity to aquatic life. We investigated the fate of PFAS in a contaminated agricultural stream receiving treated wastewater discharge from a food processing plant. We assessed accumulation of PFAS and their degradation products in the aquatic food web by sampling abiotic compartments (i.e., water, bed sediment), algae, benthic macroinvertebrates, and fish. In addition, we sampled adult aquatic insects and riparian spiders (tetragnathids) to assess the potential transfer of PFAS to the riparian food web. Downstream PFAS concentrations in water were up to three orders of magnitude higher than upstream and reflective of the PFAS composition in the effluent. Fish bioaccumulated PFAS both upstream and downstream of the effluent, but downstream fish accumulated relatively higher concentrations and more PFAS compounds. Accumulation in larval aquatic insects was highly variable, with caddisflies accumulating more PFAS compounds (n=11) compared to odonates and craneflies (n=1 to 3). Evaluation of the relative concentrations of PFAS in larval and adult caddisflies suggested compound-specific metamorphic retention. In addition, transfer of PFAS to riparian consumers was observed, with spiders showing elevated PFAS concentrations that generally reflected the composition of PFAS observed in their prey (i.e., adult aquatic insects). Our research demonstrated PFAS uptake in the stream food web and trophic transfer to riparian consumers. Variation among PFAS (including precursors), and trophic position of aquatic taxa, were important drivers of contaminant transfer.

Laura Hubbard (Co-Presenter/Co-Author), United States Geological Survey , lhubbard@usgs.gov;

Brittany Perrotta (Co-Presenter/Co-Author), United States Geological Survey, bperrotta@usgs.gov;

Christopher Kotalik (Primary Presenter/Author), United States Geological Survey, ckotalik@usgs.gov;

Dana Kolpin (Co-Presenter/Co-Author), United States Geological Survey, dwkolpin@usgs.gov;

David Walters (Co-Presenter/Co-Author), United States Geological Survey, waltersd@usgs.gov;

Alison Zachritz (Co-Presenter/Co-Author), University of Notre Dame, azachrit@nd.edu;

Johanna Kraus (Co-Presenter/Co-Author), United States Geological Survey, jkraus@usgs.gov;

James Gray (Co-Presenter/Co-Author), United States Geological Survey, jlgray@usgs.gov;

Carrie Givens (Co-Presenter/Co-Author), United States Geological Survey, cgivens@usgs.gov;

Gary Lamberti (Co-Presenter/Co-Author), University of Notre Dame, glambert@nd.edu;

Karen Kidd (Co-Presenter/Co-Author), McMaster University, karenkidd@mcmaster.ca;

14:00 - 14:15 | Freedom Ballroom F | ADULT AQUATIC INSECTS ARE PFAS VECTORS IN LINKED STREAM AND RIPARIAN FOOD WEBS

6/05/2024  |   14:00 - 14:15   |  Freedom Ballroom F

Adult Aquatic Insects are PFAS Vectors in Linked Stream and Riparian Food Webs Per- and polyfluoroalkyl substances (PFAS) are a group of anthropogenic substances that have warranted concern due to their environmental persistence, bioaccumulation, and potential toxicity. PFAS are commonly detected in aquatic ecosystems where aquatic insects can serve as contaminant vectors to riparian consumers. Despite heightened focus on environmental PFAS research, few studies have investigated PFAS trophodynamics in linked stream and riparian food webs. Here, we report PFAS concentrations, compositions, and metamorphic and trophic transfer factors for food webs representing five streams in the Farmington River watershed (Connecticut, USA) sampled between 2022 and 2023. Water, sediment, basal resources (i.e., seston, detritus, biofilm), aquatic larval and adult insects, and riparian spiders were collected and analyzed for 28 PFAS. Water samples had the highest number of compounds detected with compositions reflecting local PFAS sources. Concentrations in sediment and basal resources varied; however, composition still reflected local PFAS sources. Bioconcentration factors suggested uptake of several PFAS, including PFOS, PFOA, and PFNA, from water to larval life stages. Moreover, adult aquatic insects had the highest mean ?PFAS concentrations and metamorphic transfer factors indicated retention of PFOS, PFNA, PFHxA, and PFUnA in several insect orders. Several of these compounds were also detected in spiders, with average concentrations spanning 0.37 – 25.57 ng/g, suggesting variable exposure risk to terrestrial predators that eat adult aquatic insects. Overall, our results suggest PFAS are transferred from the aquatic ecosystem to the riparian food web via aquatic insects when they transition from an aquatic to terrestrial organism to complete their life cycle.

Kaitlyn Campbell (Primary Presenter/Author), University of Connecticut, kaitlyn.campbell@uconn.edu;

Jeff Wesner (Co-Presenter/Co-Author), University of South Dakota, Jeff.Wesner@usd.edu;

Alison Baranovic (Co-Presenter/Co-Author), University of Connecticut, Alisonbaranovic@gmail.com ;

Jenna Bartholomew (Co-Presenter/Co-Author), University of Connecticut, jenna.bartholomew@uconn.edu;

Ashley Helton (Co-Presenter/Co-Author), University of Connecticut, ashley.helton@uconn.edu;

Anthony Provatas (Co-Presenter/Co-Author), University of Connecticut, anthony.provatas@uconn.edu;

Johanna Kraus (Co-Presenter/Co-Author), United States Geological Survey, jkraus@usgs.gov;

David Walters (Co-Presenter/Co-Author), United States Geological Survey, waltersd@usgs.gov;

Jessica Brandt (Co-Presenter/Co-Author), University of Connecticut, jessica.brandt@uconn.edu;

14:15 - 14:30 | Freedom Ballroom F | UNDERSTANDING PFAS VARIABILITY IN FISHES: A REVIEW

6/05/2024  |   14:15 - 14:30   |  Freedom Ballroom F

Understanding PFAS variability in fishes: A review Per- and Polyfluorinated Substances (PFAS) are of increasing human health and environmental concern worldwide. Even with guidance, variability exists in current fish collection methods, sample sizes, species, and waterbodies sampled within and outside of Maine. Age, sex, size, metabolic rate, and other characteristics may influence PFAS accumulation in individual fish. The PFAS compounds in water responsible for accumulation in fish may also change seasonality with variability in hydrological conditions. Questions remain on how this variability, even intra- and interspecific across species, impacts PFAs assimilation and sample results in Maine fishes, especially as these samples are typically composites. To tackle these uncertainties and improve sampling regimes, we are working on compiling existing literature, including data from Maine, to evaluate variability across these axes and to model discriminatory power. This review will guide targeted data collections addressing the most critical aspects of variability with the goal of addressing uncertainties and identifying future sampling designs.

Guillermo Figueroa-Muñoz (Primary Presenter/Author), University of Maine, guillermo.figueroa@maine.edu;

Christina A. Murphy (Co-Presenter/Co-Author), U.S. Geological Survey, Maine Cooperative Fish and Wildlife Research Unit, Orono, ME, christina.murphy@maine.edu;

Joseph Zydlewski (Co-Presenter/Co-Author), USGS, University of Maine, josephz@maine.edu;

14:30 - 14:45 | Freedom Ballroom F | PER- AND POLYFLUOROALKYL SUBSTANCES (PFASS) IN WASTEWATER TREATMENT PLANTS & FRESHWATER IN AFRICA: OCCURRENCE, CHALLENGES, TOXICITY & FUTURE PERSPECTIVES.

6/05/2024  |   14:30 - 14:45   |  Freedom Ballroom F

PER- AND POLYFLUOROALKYL SUBSTANCES (PFASS) IN WASTEWATER TREATMENT PLANTS & FRESHWATER IN AFRICA: OCCURRENCE, CHALLENGES, TOXICITY & FUTURE PERSPECTIVES. Per- and polyfluoroalkyl substances (PFASs) are contaminants of emerging concern(CECs) and persistent organic pollutants, posing threats to ecosystems and human health globally. This review addresses the scarcity of research on PFASs in African freshwater and wastewater treatment plants (WWTPs), contrasting with extensive studies in other continents. Utilizing databases like Science Direct®, Google Scholar®, PubMed, Scopus, Web of Science, and Wiley Online Library, we highlight PFASs presence in African WWTPs’ discharge to waterbodies, emphasizing ecological implications and mitigation strategies. While most studies focused on PFASs levels in freshwater, fewer explored PFASs in WWTPs, a potential PFASs source to freshwater. However, a significant correlation between PFASs concentrations in WWTPs and freshwater environments emerged, suggesting WWTPs as potential sources of PFASs. Key findings indicate varying concentrations influenced by wastewater characteristics, treatment technologies, and operational conditions in WWTPs. In freshwater, factors like waste management behaviors, geographical distribution, and environmental conditions contribute to PFASs pollution. Industrial effluents, landfill leachates, and sewage discharge remain prominent sources. Resource limitations, particularly economic constraints, highlight the necessity for region-specific investigations. Urgently, specific regulatory frameworks for PFASs in wastewater management across African countries are required. International collaboration and sharing best practices are crucial for effective mitigation strategies. Future research should explore PFASs ecotoxicological effects on African ecosystems and long-term human health impacts, guiding sustainable mitigation strategies for protecting ecological integrity in Africa's receiving waters.

ASHIRAF MIIRO (Primary Presenter/Author), MAKERERE UNIVERSITY, KAMPALA-UGANDA, miiroashirafu9@gmail.com;