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CPRC SETAC 2019 Annual Spring Meeting Canaan Valley Resort & Conference Center
Davis, West Virginia
April 7 & 8, 2019
Program & Abstracts
Additional information is available at: CPRC SETAC 2019 SPRING MEETING
Welcome CPRC Members!
I am thrilled to welcome you to beautiful Canaan Valley, West Virginia for the 36th Annual
CPRC Spring Meeting! Many of us were drawn to a career or education in environmental
sciences partially due to an early connection with nature. I grew up splashing in streams of
West Virginia and flipping over rocks to find crayfish, salamanders, and fascinating
underwater bugs, which I now appreciate as mayflies, stoneflies, and caddisflies.
The 2019 Spring Meeting location inspired us to host a pre-event hike rather than a formal
workshop. We hope you will take the opportunity to come outside for a breath of fresh air
and some nature from 2-4 pm on Sunday at Blackwater Falls State Park. First, we hike out-
and-back to Pase Point for an overlook of the mountains and Blackwater River, and then
drive a short distance to see the waterfall. If you cannot make it to the hike, meet us at 6
pm in quaint downtown Davis, WV at the Wicked Wilderness Pub n’ Parlor for dinner and
local craft beer, craft soda, or a glass of mountain spring water.
On Monday, we look forward to full and engaging day of technical platforms and posters
from both professional and student members. The chapter proudly supports our students
with a mentoring lunch and cash awards for top posters and platforms. Dr. Peter Tango of
USGS will provide a lively keynote address, outlining the history and current
understanding of harmful algal blooms in the Chesapeake Bay.
Regional SETAC chapters like ours foster the opportunity for
small meetings and meaningful one-on-one interactions. We
are fortunate to have a group of incredibly talented,
accomplished, and personable scientists and students in our
region. Take a moment at the poster social and coffee breaks
to meet someone new. A short conversation may be the first
step to building a network of career-long colleagues. Wherever
you are in your career, I hope you always feel welcome in our
chapter and continually find a way to grow with CPRC.
Jennifer Flippin CPRC SETAC President 2019-2020
Pre-meeting Hike at Blackwater Falls
Sunday, April 7th 2:00 pm – 4:00 pm
Join us on Sunday afternoon for a hike on Pase
Point Trail. Meet at 2 pm in Blackwater Falls
State Park (1584 Blackwater Lodge Rd, Davis,
WV 26260) at the Nature Center parking lot.
The given address will get you to the park but is
not the meeting point for the hike. Once you get
to the stop sign in the park, follow signs to the
lake or nature center. Look for someone holding
a CPRC sign in the Nature Center parking lot.
The Pase Point Trail begins as Dobbin House Trail and winds past Lake Pendleton
and along the edge of Blackwater River Gorge to a scenic overlook of the canyon
and river. We will walk through a forest and across footbridges spanning clear
mountain tributaries. Elevation gain on the trail is a modest 423 feet; the elevation
change is gradual with no extended trudges up a steep hill! The total distance, out
and back, is just over 4 miles.
Mandatory Gear: Wear sturdy shoes suitable for hiking that can get muddy, and
dress in layers for the weather.
Optional Gear: Water bottle, snacks, hiking poles or walking stick, camera, hat.
After we return to the Nature Center parking lot, join us on a short drive to another
part of the park to see the falls! The tannin-stained Blackwater River cascades
approximately 60 feet to create a uniquely beautiful feature. Walk down the 200
steps to see the waterfall up-close or view from one of the more easily accessible
overlooks.
In case of bad weather, watch your email for updates and we will try to make a call
on the hike by Saturday afternoon. If we are unable to hike, plan to meet at the
Purple Fiddle (a historic general store turned charming music venue) in Thomas,
WV. Explore the artsy town and listen to a free concert for the afternoon. (Concert
starts at 1:00pm.)
Dinner Social: Sunday, April 7th
6:00 pm
Kick off the spring meeting with a relaxing evening to catch up with colleagues
and greet new faces at our informal dinner social. Meet us at the Wicked
Wilderness Pub n’ Parlor (128 5th Street, Davis, WV 26260) at 6 pm Sunday
evening. Enjoy a wholesome or hearty meal along with local craft beer, craft sodas,
or a glass of mountain spring water.
This event is not included in the cost of registration (pay on your own).
If you miss the hike, but arrive in Davis before 6 pm, consider taking a moment to
check out Blackwater Falls, Lindy Point Overlook (Blackwater Falls State Park), a
local trail, or the shops in Thomas or Davis, WV.
Monday’s Keynote Speaker: Dr. Peter Tango, Chesapeake Bay
Monitoring Coordinator, USGS, Annapolis, MD
Title: What happened to Pfiesteria hysteria? Chesapeake Bay Harmful Algal
Blooms 20 Years after the “Cell from Hell”
Abstract: Pfiesteria hysteria embraced the Chesapeake Bay region in the late 1990s when it
was hypothesized that a dinoflagellate named Pfiesteria piscicida (piscicida meaning ‘fish
killer’) was found in Chesapeake Bay waters. Pfiesteria, or a Pfiesteria-like organism, was
believed to be causing fish population health events, fish kills and human illnesses in the
laboratory and the field. A convergence of all these forms of events occurred along the lower
Pocomoke River in 1996-1997 drawing enhanced local to global attention to harmful algal
bloom (HAB)-related issues. Significant investments were made in understanding
phytoplankton community composition in our region with an eye toward potential risks to
humans and bay living resources due to possibly toxic HAB species. Species monitoring, toxin
identification and impact assessments in Chesapeake Bay and its tidal tributaries diversified over
the 20 years after the discovery of the “cell from hell”. This presentation will review how our
recognition of HAB species in the region has evolved, present regional events associated with
toxic HAB activity, and give a sense for the
relative prevalence of HAB impacts
compared to other stressor impacts on living
resources in the Chesapeake Bay region.
Biography: Peter was hooked on science
ever since a 5th grade teacher inspired him to
start a birding life list. That was 1976. A
passion for science and maintaining the
birding life list continues! Peter's degree
work in forest biology (BS), wildlife science
(MS) and fisheries management (PhD)
supports his position with the USGS as the
Chesapeake Bay Monitoring Coordinator.
Serving the Chesapeake Bay Program
partnership, Peter's position also involves serving in the roles of Scientific Technical Assessment
and Reporting team Coordinator and over a decade of service as the Chair of the Criteria
Assessment Protocol Work Group. Running, fishing, hunting, hiking, gardening, writing, biking
and more all help round out the hours in a day keeping life full of good health, fitness, and plenty
of outdoor adventures.
Chesapeake-Potomac Regional Chapter SETAC
2019 Annual Spring Meeting
Canaan Valley Resort & Conference Center, Davis, West Virginia
Time Meeting Program, Monday April 8, 2018
8:15 – 8:30 AM Poster and Sponsor display set-up
8:30 – 9:30 AM Registration Opens / Breakfast / Networking & Poster Social
9:30 – 9:45 AM Welcome and Opening Remarks –Ben Burruss, CPRC President
Jennifer Flippin, CPRC Vice President
9:45 - 10:00 AM CPRC Update & Business Meeting
10:00 – 10:15 AM *Mandar Bokare, UMBC - Ongoing inputs of PCBs to the Anacostia River
from its tributaries during storm and base flow conditions
10:15 – 10:30 AM *Ross Cooper, Virginia Tech. - Spatial and temporal changes in water quality
in the Shenandoah River watershed
10:30 – 11:30 AM Refreshment Break and Poster Social
11:30 – 11:45 AM *Jada Damond, UMBC - The challenge of measuring activated carbon dose
in sediments
11:45 – 12:00 AM
*Oindrila Ghosh, UMBC - Comparison of PRC adjustment methods applied
to sediment porewater concentrations in the tributaries of the Anacostia River,
Washington DC.
12:00 – 12:15 PM *Meredith E Seeley, VIMS - Effect of different microplastics on sediment
microbial communities and nitrogen cycling
12:15 – 12:30 PM SETAC-NA Update – Lisa Ortego, Board of Directors SETAC-NA
12:30 – 1:45 PM Lunch & Mentor/Mentee Tables
1:45 – 2:45 PM
Keynote Speaker – Peter Tango, USGS – “What happened to Pfiesteria
hysteria? Chesapeake Bay Harmful Algal Blooms 20 Years after the “Cell
from Hell”
2:45 – 3:45 PM Refreshment Break and Poster Social
3:45 – 4:00 PM
Meredith Bohannon, UMD - Temporal and spatial trends of organochlorine
compounds in Herring Gull (Larus argentatus) eggs from the Great Lakes
in Ontario, Canada and Michigan, USA, 2002-2017
4:00 – 4:15 PM Nathalie Lombard, UMBC - Seasonal changes in freely dissolved PCB
concentration in the Anacostia tributaries
4:15 – 4:30 PM Amanda Milligan, Eurofins - Evaluating the influence of temperature on
reproduction in mysid life-cycle toxicity Tests
4:30 – 4:45 PM Hans Plugge, Verisk3E - Ecological hazard screening of mixtures
4:45 – 5:00 PM Closing Remarks & “Student Presentation Awards”
* Student Presentation Award Competition
Poster Presentation (*Student Poster Award Competition):
* Thanh-Binh Duong, UMW - Microplastics: Presence, concentrations, and influence on
toxicity of methoxychlor to Daphnia magna
* Charles Daniel Furst, Towson - Exploring effects of chemical stressors on terrestrial
invertebrates: development of a novel method and model using crickets, Acheta
domesticus
* Mary Hoffman, UMW - Assessing the effects of sulfoxaflor on the physiology,
reproduction, and behavior of Daphnia magna
* Amanda Isabella, Towson - Building a bigger picture: Exploring effects of chemical
mixtures in individuals and populations of Daphnia magna for use in predictive modeling
Michael Jirsa, EA Engineering - The utilization of a biological and chemical translators
for the adjustment of site specific copper permit limits
* Sarahana Joshee, UMBC - PCB levels in the surface water, sediment porewater, and
benthic organisms in Back River watershed
* Sarah Lanasa, Towson - What’s in your herbicide? Considering the toxicity of
herbicide active ingredients, “safeners”, formulation and photolysis products on non-
target algae species
* Erica Loudermilk, UVA - Evaluating effects of algae-mediated treatment on
elicitation of antibiotic resistance in wastewater treatment plants
* Taylor Motley, UMD - Analysis of physical and biological degradation of PBDEs in
historical limed biosolids and THP-AD treated biosolids
Mary Rogers, Towson - Characterization and modeling for remediation of an acid mine
drainage system in Centralia, Pennsylvania.
* Alterra Sanchez, UMD - Fabricating microplastics with standardized surface area for
quantifying the sorption of organic pollutants
* Caitlin Weible, Towson - Effects of dermal exposure to perfluroocatesulfonic acid
(PFOS) on Brown Anoles (Anolis Sagrei)
MORNING SESSION 9:30 – 10:30
1
Primary Contact: Mandar Bokare
Email: [email protected]
Ongoing inputs of PCBs to the Anacostia River from its tributaries during storm and base flow
conditions
Mandar Bokare (University of Maryland Baltimore County), Nathalie Lombard (University of Maryland
Baltimore County), Timothy Wilson (United States Geological Survey (USGS) – NJ Water Science Center),
Upal Ghosh (University of Maryland Baltimore County)
Polychlorinated biphenyls (PCBs) are major contaminants of concern in the Anacostia River. Elevated PCB
levels in fish tissue have led to consumption advisories in the District of Columbia. Uptake of PCBs in
aquatic organisms is governed by their dissolved concentration in water. In this study, polyethylene (PE)
passive samplers were used to measure dissolved PCB concentration in Anacostia River and its tributaries.
Passive sampler measurements, representing base flow conditions, were integrated with PCB
concentrations in storm-flow suspended solids, measured by United States Geological Survey, to delineate
PCB inputs from tributaries at storm and base flow conditions. For March – July 2017 sampling period,
base-flow PCB concentrations ranged from 0.01 – 6.5 ng/L across the tributaries, while average
concentration in the river was 1.6 ng/L. Dissolved PCB concentration in Lower Beaverdam Creek (LBC) was
3.4 times the concentration in the Anacostia River. At other tributaries, concentrations were lower than
those in the river. Dissolved PCB concentrations in tributaries at storm flow conditions were up to 38 times
lower than their respective concentrations at base-flow conditions, indicating that water quality impacts
from suspended-sediment bound PCBs are lower than those from dissolved PCBs at base-flow. Total PCB
loads, including dissolved- and particulate organic carbon-associated loads, were estimated at 580 g/year.
Overall, 50% of dissolved loads are attributed to storm-flow conditions with 95% coming from LBC. LBC
also had the most negative impact on water quality with higher chemical activity of dissolved PCBs at both
base and storm-flow conditions as compared to PCBs in the Anacostia River. LBC also contributed 83% of
the total dissolved load (storm + baseflow). Although storms delivered 98% of total sediment load
delivered to the Anacostia River, these sediments were relatively cleaner than the surface sediments in
Anacostia River and help in the natural attenuation of PCBs. These results highlight the importance of
tracking dissolved pollutants in aquatic systems and the need to complement existing approaches for
estimating pollutant loadings with better understanding of chemical activity of pollutants obtained
through passive sampling techniques.
MORNING SESSION 9:30 – 10:30
2
Primary Contact: Ross Cooper
Email: ross&@vt.edu
Spatial and Temporal Changes in Water Quality in the Shenandoah River Watershed
Ross Cooper (Virginia Tech), Serena Ciparis, Ph.D. (Virginia Tech)
The Shenandoah River watershed contains a high density of animal agricultural operations that produce
large amounts of nutrient- and bacteria-containing waste. The Commonwealth of Virginia has
implemented bacteria and sediment Total Maximum Daily Loads (TMDLs) for many Shenandoah River
tributaries. Despite their implementation, there is a lack of data to demonstrate water quality
improvement. This study analyzed long-term trends in nutrient concentrations as well as the correlation
between these trends and pollution mitigation plans, land use changes, and agricultural best management
practices (BMPs). For 27 sites, publicly available citizen-collected data from Friends of the Shenandoah
River (FOSR) were analyzed for temporal trends (2002-2017) in nitrate, ammonia, orthophosphate,
turbidity and discharge. Slopes from regression analyses were ranked as positive, negative, or no change.
These rankings were used in logistic regression to describe the relationship between water quality
characteristics, applied BMPs, and TMDL status. Generally, there was no relationship between
implemented BMPs in the watershed or TMDL status and analyte trends. Nitrate concentrations increased
over time in the majority of tributaries. The probability of increasing nitrate concentrations in
winter/spring was related to the amount of agricultural land in tributary watersheds. The probability of
increasing nitrate concentrations in summer/fall was related to the BMP practice of linear fence
installation. Sites downstream of wastewater treatment plants showed decreasing orthophosphate and
stable nitrate trends, suggesting regulations have been more effective in addressing point versus nonpoint
source pollution. Results indicate a general disconnect between water quality, TMDL status, and BMP
implementation, indicating a need for further assessment of applied practices and possible reevaluation
of approaches to nonpoint source pollution mitigation.
MORNING SESSION 11:30 – 12:30
3
Primary Contact: Jada Damond
Email: [email protected]
The challenge of measuring activated carbon dose in sediments
Jada Damond (University of Maryland, Baltimore County), Cynthia Gilmour (Smithsonian Environmental Research
Center), Upal Ghosh (University of Maryland, Baltimore County)
Activated carbon (AC) is used as an amendment for in-situ remediation of persistent organic pollutants (POPs) in
contaminated sediments. In-situ application of AC at a dose of 1-5% by weight has been demonstrated to significantly
reduce bio-uptake into aquatic food webs. The most important factors in the success of the technology are the
application of the correct dose of AC, uniformity of the dose in the treated area, and persistence of the applied AC dose
over time. However, there is no standard method to measure the amount of AC in sediment, and researchers have
used a variety of techniques including measures of total organic carbon, loss on ignition, traditional black carbon
determination, and a specialized method for AC. In this work, two different carbon treatments (AC and Biochar) were
measured for the amount of black carbon after 7 years of implementation in a field pilot study. Three analytical methods
(loss on ignition, total organic carbon, and specialized AC measurement) were compared for the efficacy of measuring
the amount of black carbon present in the sediments. A comparison of the accuracy and precision of each method and
recommendation for adoption is presented in this study. Accurate measurement of AC in sediments as demonstrated
in this study is necessary to build confidence in the adoption of in-situ remediation of sediments.
MORNING SESSION 11:30 – 12:30
4
Primary Contact: Oindrila Ghosh
Email: [email protected]
Comparison of PRC adjustment methods applied to sediment porewater concentrations in the tributaries of the
Anacostia River, Washington DC.
Oindrila Ghosh (Department of Chemical, Biochemical and Environmental Engineering, University of Maryland
Baltimore County, Baltimore, Maryland 21250, United States), Nathalie Lombard (Department of Chemical,
Biochemical and Environmental Engineering, University of Maryland Baltimore County, Baltimore, Maryland 21250,
United States), Mandar Bokare (Department of Chemical, Biochemical and Environmental Engineering, University of
Maryland Baltimore County, Baltimore, Maryland 21250, United States) , Upal Ghosh (Department of Chemical,
Biochemical and Environmental Engineering, University of Maryland Baltimore County, Baltimore, Maryland 21250,
United States)
Polymeric passive sampling devices have increasingly been used in the measurement of low levels of freely dissolved
concentrations of hydrophobic organic contaminants like polychlorinated biphenyls (PCBs) in surface water and
sediment porewater and provide an estimate of pollutant bioavailability to aquatic organisms. Passive samplers are
kinetically inhibited to reach equilibrium in stagnant sediments within practical deployment times. Thus, accurate
measurement of these concentrations requires adequate correction for non-equilibrium conditions by using Performing
Reference Compounds (PRCs). Different methods of conducting these corrections do not always yield similar results and
this can have possible implications for remedial actions. In this study, four PRC adjustment methods were applied to
passive samplers deployed in sediment porewaters of tributaries of the Anacostia River in Washington DC. The river is
under a fish consumption advisory due to elevated levels of PCBs in fish and is undergoing a remedial investigation to
determine PCB sources to the river, including inputs from its tributaries.The first two methods are based on a simple
first order kinetic model with linear correlation between: 1) sampler uptake rate (ke) and polymer-water partitioning
rate (Kpw) and 2) sampler uptake rate (ke) and molar volume (Vm). The third method is the Molar volume Adjustment
(MVA) method that is based on an empirical non-linear relationship between the apparent sampling rate (Rs) and Vm.
The fourth adjustment method uses a PRC Correction Calculator software which is based on a diffusion-based model.
Comparison of porewater values from these adjustment methods reveals that ke-Kpw and the MVA methods gave
similar results to the unadjusted concentrations, whereas the ke-Vm and Diffusion methods estimate are higher than
the non-adjusted values. These differences are consistent across all sites analyzed. The theoretical explanation for the
consistent differences in the porewater concentration levels is currently being explored and can help in evaluating the
better suited PRC correction method for a given flow regime.
MORNING SESSION 11:30 – 12:30
5
Primary Contact: Meredith E Seeley
Email: [email protected]
Effect of different microplastics on sediment microbial communities and nitrogen cycling
Meredith E. Seeley (Virginia Institute of Marine Science, William & Mary), Bongkeun Song (Virginia Institute of Marine
Science, William & Mary), Robert C. Hale (Virginia Institute of Marine Science, William & Mary)
Polymer type has been shown to influence the composition of floating marine debris biofilm communities. However, no
previous studies have investigated effects of plastics on sediment microbial communities and their biochemical
activities, even though microplastics have been found across open ocean, coastal and inland sediments. Here, we
present the results of a marsh sediment microcosm experiment established with microplastics (53-300 um) of different
petroleum-based polymers (polyethylene [PE], polyvinyl chloride [PVC] and polyurethane foam [PUF]) and one bio-
polymer, (polylactic acid [PLA]). We characterized the sediment bacterial compositions and functional gene abundances
after 7 and 16 days using 16S MiSeq analysis, and measured denitrification rates and nutrient fluxes. We found that
bacterial community compositions were different between the biopolymer, petroleum-based polymers and plastic-free
sediment, with PVC being the most distinctly different community. Nitrification gene abundances and nutrient fluxes
revealed that nitrification was highest in the biopolymer (PLA), followed by PUF and PE, but almost completely inhibited
in PVC. Correspondingly, denitrification gene abundances and denitrification rates (calculated via sediment slurry
incubation using 15NO3- tracer) revealed an inhibition of denitrification in the PVC, and the highest denitrification
activity in PLA treatments. Interestingly, denitrification and nitrification were higher in PE, PUF and PLA treatments than
the control (no microplastic), suggesting some plastics may enhance sedimentary nitrogen cycling processes. Overall,
this study highlights the distinct effect of different plastics on structure and function of sediment communities, and calls
for expanded research in this area.
AFTERNOON SESSION 3:45 – 4:45
6
Primary Contact: Meredith Bohannon
Email: [email protected]
Temporal and Spatial Trends of Organochlorine Compounds
in Herring Gull (Larus argentatus) Eggs from the Great Lakes
in Ontario, Canada and Michigan, USA, 2002-2017
Meredith Bohannon (Department of Environmental Science and Technology, University of Maryland, College Park, MD,
USA), Kenneth Drouillard (Great Lakes Institute for Environmental Research, University of Windsor, Windsor, ON,
Canada), Kimberley Hughes (Broadwing Biological Consulting, Pickering, ON, Canada), Shane De Solla (Ecotoxicology
and Wildlife Health Divisions, Environment and Climate Change Canada, Burlington, ON, Canada), and William
Bowerman (Department of Environmental Science and Technology, University of Maryland, College Park, MD, USA)
The Clean Michigan Initiative-Clean Water Fund has supported a 15-year-long biomonitoring program of several
organochlorine (OC) contaminants in herring gull (Larus argentatus) eggs from Lake Erie, Lake Huron, Lake Michigan,
Lake Superior, and the St. Mary’s River in Michigan from 2002-2006 and 2008-2017. This monitoring study provides a
dataset from the United States that mirrors the Environment and Climate Change Canada’s (ECCC) Great Lakes Herring
Gull Contaminant Monitoring Program dataset. These contaminants include polychlorinated biphenyls (PCBs),
polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and several organochlorine
pesticides such as dichlorodiphenyltrichloroethane (DDT) and its ubiquitous metabolite
dichlorodiphenyldichloroethylene (DDE). 77 compounds in total were analyzed, as well as 60 TEQs calculated for
individual PCBs, PCDDs, and PCDFs. Every year, thirteen eggs were randomly selected from each colony (two colonies
per Lake/River, one egg per nest) and analyzed via gas chromatography (GC) at the Great Lakes Institute for
Environmental Research, using a similar protocol used by ECCC. Eggs were either analyzed individually or as composites
and spatial and temporal trends were assessed for burdens in eggs. Additionally, a Wildlife Contamination Index (WCI)
was calculated using several legacy compounds including organochlorines, PCDDs, and PCDFs to assess risk to
piscivorous wildlife, rank colonies based on exceedances of guidelines and assess temporal changes in exceedances of
guidelines at individual colonies. Calculation of WCIs is ongoing. General trends in concentrations over this period of
time reveal that Lake Erie is ranked the most contaminated for ΣPCBs, octachlorostyrene, dieldrin, α-Chlordane, p,p’-
DDT, and p,p’-DDD. Lake Superior is ranked the most contaminated for β-Hexachlorocyclohexane, oxy-Chlordane, and
cis-Nonachlor. These and other values in some cases exceed the NOAELs or LOAELs for double-crested cormorants
(Phalacrocorax auritus), which stand in for toxicity reference values for herring gulls. These data taken together
demonstrate that the Great Lakes still carry a relatively high burden of legacy contaminants that may be affecting the
health of avian populations.
AFTERNOON SESSION 3:45 – 4:45
7
Primary Contact: Nathalie Lombard
Email: [email protected]
Seasonal changes in freely dissolved PCB concentration in the Anacostia tributaries
Nathalie Lombard (UMBC, Baltimore, MD, USA), Mandar Bokare (UMBC, Baltimore, MD, USA), Varapapa Thodpanich
(UMBC, Baltimore, MD, USA), Samuel Magee (UMBC, Baltimore, MD, USA) Jeremy Drew (UMBC, Baltimore, MD, USA),
Jada Damond (UMBC, Baltimore, MD, USA), Dev Murali (DC Department of Energy & Environment, Washington, DC),
Upal Ghosh (UMBC, Baltimore, MD, USA)
Located within a major urban environment, the Anacostia River continues to receive inputs of legacy pollutants from its
watershed, resulting in bioaccumulation in fish and the issuance of fish consumption advisories. A detailed analysis of
ongoing inputs to the river was conducted to supplement the Remedial Investigation/Feasibility Study of the tidal
Anacostia River. An initial passive sampling study over a three-month period in Summer 2016 showed that all Anacostia
main tributaries have PCB concentration above USEPA water quality criteria for fish consumption. The Lower Beaverdam
Creek was identified as the main source of both dissolved and particle-associated PCBs to the river. The study was
pursued over a full year to 1) compare PCB concentration a year apart 2) measure PCB concentration changes over the
4 seasons 3) track down PCB sources in Lower Beaverdam Creek. To address this aim, passive samplers were
consecutively deployed from Spring 2017 to Winter 2017-2018 at the same locations of the initial study, plus two
additional sites in the Lower Beaverdam Creek Tributary. Results of the study confirmed PCB concentration trends in
the Anacostia watershed, and identified two potential hot spots of PCB contamination at Lower Beaverdam creek. The
full year monitoring showed small changes in PCB concentration over time that generally followed seasonal water flow
variations with increasing dissolved concentration with increasing mean flow velocity. The seasonal changes will be
incorporated in the fate and transport model to support the feasibility study of the Anacostia River.
AFTERNOON SESSION 3:45 – 4:45
8
Primary Contact: Amanda Milligan
Email: [email protected]
Evaluating the Influence of Temperature on Reproduction in Mysid Life-Cycle Toxicity Tests
Amanda Milligan (Eurofins), Mary Beth Claude (Eurofins)
The saltwater mysid (Americamysis bahia) life-cycle toxicity test is notoriously difficult to perform. In the world of
contract research organizations, consistently meeting all guideline validity criteria during mysid life-cycle toxicity tests
is a common problem. There are conflicting recommendations in current mysid life-cycle guidelines. The draft EPA
OPPTS 850.1350 Mysid Chronic Toxicity Test guideline (1996) recommends that the test temperature should be 25 ±
2°C, while the ASTM Standard E 1191-03a: Standard Guide for Conducting Life-Cycle Toxicity Tests with Saltwater Mysids
(2014) states that the test should be conducted at temperatures of 27 ± 1°C, implying that a higher temperature is better
for the outcome of the test. Additionally, studies that have investigated the effects of temperature on mysid
reproduction have concluded that increased temperature accelerates reproductive processes. However, the OECD
Detailed Review Paper on Aquatic Arthropods in Life Cycle and Two-Generation Toxicity Tests (2005) states that the test
temperature should be 25 ± 1°C and acknowledges that higher temperatures may decrease embryo and larval survival.
An evaluation of our historical control data from 56 studies conducted between 2012 and 2017 suggested that there
was a trend between lower mean water temperatures and increased production of young. We analyzed and presented
the historical control temperature and reproduction data with Tableau Desktop Professional Edition. Using this graphical
visualization software, an association was found between lower mean water temperatures and increased production of
young. We concluded that while conducting life-cycle tests closer to 26°C might result in increased mysid growth and
decreased time in between broods as the literature suggests, it will result in decreased production and survival of young.
The data from our study indicates that approximately 24.5 to 25.5°C is the ideal range for the reproductive phase in
mysid life-cycle toxicity tests. Since the EPA OPPTS 850.1350 guideline is currently under revision, we propose that the
EPA modifies the recommended temperature range from 25 ± 2°C to 25 ± 1°C, and further acknowledge that the
reproductive phase should be conducted at a cooler temperature range of 24.5 to 25.5°C.
AFTERNOON SESSION 3:45 – 4:45
9
Primary Contact: Hans Plugge
Email: [email protected]
Ecological Hazard Screening of Mixtures
Hans Plugge, Verisk3E, Bethesda, MD
Very few approaches exist for screening ecological hazard from mixtures, and definitely very few indeed for screening
non-binary complex mixtures. Here we describe our hazard screening approach that can accommodate
mixtures/products with up to 256 chemicals. Hazard screening is performed using 6 ecological endpoints: acute and
chronic algae, fish and invertebrate toxicity. Bioaccumulation and biodegradation are considered in extrapolating acute
to chronic data where (limited) data are available. Toxicity data are transformed logarithmically to numerical scores on
a scale from 1-1,000 with 1000 being the greenest (i.e. equalling water.) Score interpretation is aided by a modified
traffic light scale: red to dark green in 6 steps. Massive normalized ecotoxicological databases (e.g. Acute Invertebrate
toxicity exceeds 57,900 records) are used to derive the scores. The underlying data for each score is auditable i.e. the
raw data can be displayed. Custom, non-literature, data can be entered.
Given the scores are normalized into unit-less scores they can be manipulated mathematically. Mixtures can thus be
rated numerically using logarithmically weighted geometric means. (Given that data is generally not normally distributed
this is a more mathematically correct averaging method while at the same time assuring that the chemical with the
lowest score i.e. the more hazardous chemical is preferentially weighted.) Given that the most often used (GHS) mixture
rule result in a classification “score” rather than a score on a continuous scale, this is a very fast way of deriving numerical
hazard assessments for mixtures. An example for hazard analysis in alternatives assessments will be presented.
POSTER SESSION
1
Primary Contact: Thanh-Binh Duong
Email: [email protected]
Microplastics: Presence, concentrations, and influence on toxicity of methoxychlor to Daphnia magna
Thanh-Binh Duong (Dept. of Earth and Environmental Sciences, University of Mary Washington), Ben
Kisila (Dept. of Earth and Environmental Sciences, University of Mary Washington), Mary Hoffman (Dept.
of Earth and Environmental Sciences, University of Mary Washington), and Tyler Frankel (Dept. of Earth
and Environmental Sciences, University of Mary Washington)
Microplastics (MPs) are defined as plastic particles <5mm in diameter which are generated through the
manufacturing of microbeads for cosmetics and personal care products, as well as from the physical and
chemical fragmentation of larger plastic pieces. MPs primarily enter aquatic environments through
wastewater treatment plant (WWTP) discharge, where they can remain suspended and navigate into
connected waterways or deposit into sediments. Due to their small size they are easily ingested by aquatic
organisms, resulting in detrimental health effects such as digestive tract obstructions, feeding debilitation,
and overall energy depletion. MPs have also been suspected to sorb and mobilize chemicals such as
pharmaceuticals and pesticides, suggesting that interactions between these two types of pollutants may
result in an altered biological response compared to the effects of each individual contaminant. This study
assessed 1) the presence and concentrations of MPs in sediment samples obtained downstream from a
wastewater treatment plant and 2) the potential synergistic or antagonistic effects of polyethylene MPs
and the organochlorine pesticide methoxychlor on the viability and behavior of Daphnia magna. Water
and sediment samples were obtained from the Little Falls WWTP outfall (Stafford, VA) and the presence,
type, and quantity of MPs assessed using light microscopy. Adult D. magna were exposed to either 1)
virgin 10-20µm polyethylene pellets (0, 12.5, 25, 50, or 100 mg/L), 2) methoxychlor (0, 1.0, 2.5, 5.0, or 10
μg/L), or 3) various combinations of the same pellet and methoxychlor concentrations for 48hrs using a
static exposure method. Mortality, paralysis, and changes in behavior were assessed every 24hrs for all
treatments, as well as the number of ingested pellets by each individual for the MP treatments. While this
project is currently ongoing, we expect to find a significant difference in mortality rates when exposed to
the combination of MP pellets and methoxychlor compared to the effects from each contaminant alone.
Thus far, few studies have examined the ability of MPs to influence the toxicity of organochlorine
pesticides and other chemicals. Our findings will help to expand what is known about the impacts of MP
pollution on aquatic environments.
POSTER SESSION
2
Primary Contact: Charles Daniel Furst
Email: [email protected]
Exploring effects of chemical stressors on terrestrial invertebrates: development of a novel method
and model using crickets, Acheta domesticus
Charles Daniel Furst, Caitlin Weible, Andrew East, and Dr. Chris J. Salice
Per- and polyfluoroalkyl substances (PFAS) are a large class of chemicals that are persistent environmental
pollutants. They are major components of many industrial flame-retardants, and can also be found in
commercial products including clothing and cookware. Studies have been conducted on terrestrial, avian,
and aquatic vertebrates, but there are little data regarding PFAS toxicity to terrestrial invertebrates,
despite the importance of these receptors for ecosystem function. The primary goal of this research was
to investigate the impacts of a specific environmentally relevant PFAS, perfluorooctanesulfonic acid
(PFOS), on an invertebrate species. House crickets (Acheta domesticus) were chosen for this study due to
their high abundance in the environment as well as their significance as an important food source for
many avian and reptilian species. Crickets were exposed to PFOS at 0.003, 0.03, 0.3, 3, 30, 300 mg/L via
drinking water over two durations (72hr and 120 hr) using a newly invented device called the “Falcon
Dress” to explore acute toxic effects through drinking water. The device uses a centrifuge tube and filter
paper to allow the crickets to drink contaminated water in a manner that limits evaporative loss. The LC50
was determined to be 20.7mg/L, in a 72 hr exposure. Mortality at low concentrations prompts concern
about invertebrate exposure and ecosystem effects in terrestrial habitats with high PFOS contamination,
as crickets are an important food source for many lizard and bird species at higher trophic levels. This
study will also inform future studies exploring longer exposure as well as sub-lethal effects of PFOS.
POSTER SESSION
3
Primary Contact: Mary Hoffman
Email: [email protected]
Assessing the effects of sulfoxaflor on the physiology, reproduction, and behavior of Daphnia magna
Mary Hoffman (a), Thanh-Binh Duong (a), Ben Kisila (a), and Tyler Frankel (a)
(a) Department of Earth and Environmental Sciences, University of Mary Washington
Insecticides are widely used to control invertebrate pest populations that threaten crop health, and often
enter nearby waterways due to improper application methods or as a component of agricultural runoff.
Sulfoxaflor, a sulfoxomine pesticide that has recently been approved by the USEPA, has shown increased
rotational use due to the lack of cross-resistance exhibited by many insect species. Sulfoxaflor binds to
insect nicotinic acetylcholine receptors (nAChR), causing overactivation of these receptors which leads to
paralysis and ultimately death. Preliminary exposure studies using rats and mice have shown neonatal
abnormalities and the development of liver tumors, and slight effects to the growth of fathead minnow
and moderate oral toxicity in birds have also been observed. Little research into the lethal and sub-lethal
effects of sulfoxaflor on aquatic invertebrates has been conducted since its approval for use by the USEPA.
As such, this study is designed to identify the potential environmental effects of sulfoxaflor at 0, 0.1, 1,
10, 100, and 1000 µg/L on Daphnia magna physiology, reproduction, and behavior. D. magna were
exposed to treatments for 48hrs and the number of paralyzed or dead individuals assessed after 24 and
48hrs. To determine the impacts of sulfoxaflor on reproduction and mobility, < 24hr old individuals were
tested using a 21d static replacement exposure (100% every 48hrs). The number of progeny from each
individual were quantified daily, and effects on mobility were assessed using ToxTrac behavioral analysis
software. To examine effects on heart rate, individual adults were exposed for 48hrs and heartrates (bpm)
assessed at 5 min, 10 min, 15 min, 24hr, and 48hr. While this research is still ongoing, it is expected that
exposure to sulfoxaflor will cause increased mortality as well as decreases in fecundity, mobility, and
heartrate in D. magna. Our results will help to elucidate the potential impacts of sulfoxaflor pollution on
aquatic environments.
POSTER SESSION
4
Primary Contact: Amanda Isabella
Email: [email protected]
Building a bigger picture: Exploring effects of chemical mixtures in individuals and populations of
Daphnia magna for use in predictive modeling
Amanda Isabella (Towson University), Andrew East (Towson University), and Dr. Christopher Salice
(Towson University)
Traditional toxicity testing is used to assess adverse effects of chemicals on environments using tests of
individual organisms. However, traditional toxicity tests largely fail to account for ecological factors such
as predation and food quality or quantity, as well as the effects of additional chemical stressors. In this
study, a binary mixture of two environmentally relevant chemicals were used to create a complex stressor
environment. A pulse of pyraclostrobin, a fungicide, was applied to waters chronically stressed with high
conductivity due to sodium chloride, which is common in aquatic systems from road de-icing activities.
These compounds were selected due to their physiochemical attributes but also their likelihood to co-
occur in Mid-Atlantic waterways. To first assess these stressors, we conducted two 48-hour acute studies
with Daphnia magna exposed to various combinations of sodium chloride and pyraclostrobin. Results
from the acute experiments indicated that, though pyraclostrobin and chloride act independently via
different mechanisms of toxicity, there was an additive impact from simultaneous exposure to two
chemical stressors on D. magna mortality. We then conducted a laboratory-population experiment with
a full factorial design to evaluate the effects of both chemicals under more ecologically realistic conditions.
Results for the laboratory-population experiment showed that chloride delayed time to first reproduction
and an addition of pyraclostrobin increased acute mortality both in individuals and at the population level.
The collective results from acute and population-level studies will be used to develop and implement
Independent Action models as well as computationally more complex, individual-based models. We will
then explore whether these different modeling constructs can predict effects of chemical mixtures.
Collectively, these experimental results and model developments will help improve the quality of
ecological risk assessments by specifically enhancing our ability to extrapolate from simple toxicity
experiments to more complex exposure environments.
POSTER SESSION
5
Primary Contact: Michael Jirsa
Email: [email protected]
The Utilization of a Biological and Chemical Translators for the Adjustment of
Site Specific Copper Permit Limits
Michael Jirsa(EA Engineering, Science, and Technology, Inc., PBC), Michael Chanov(EA Engineering,
Science, and Technology, Inc., PBC;
The development of site-specific water quality criteria for individual metals through the
performance of both biological and chemical translators has successfully enabled permittees to
modify National Pollutant Discharge Elimination System (NPDES) discharge permit single
metal permit limits. This testing concept is based on the U.S. Environmental Protection Agency
(EPA’s) recognition that the metals can be substantially less toxic in an effluent/receiving water
matrix than in clean laboratory water, on which the single metal permit limits are often based.
Additionally, the ratio of dissolved to total fractions of the metal can greatly affect the toxicity of
the specific metal. One metal in particular that has commonly been evaluated through these
studies is copper. The toxicity of copper is dependent on site-specific factors such as pH,
hardness, total suspended solids and dissolved organic carbon. Copper studies conducted by EA
have been utilized by industrial and municipal dischargers to obtain site specific water quality
criteria. This presentation outlines two studies conducted utilizing the translator methodologies
to obtain site specific permit limits for copper.
POSTER SESSION
6
Primary Contact: Sarahana Joshee
Email: [email protected]
PCB levels in the surface water, sediment porewater, and benthic organisms in Back River watershed
Sarahana Joshee, Mandar Bokare, Wesley Schmidt, Kevin Brittingham, Upal Ghosh
Polychlorinated biphenyls (PCBs) are major contaminants of concern in Back River, resulting in fish
consumption advisories in Maryland. In collaboration with the Baltimore County and the Maryland
Department of Environment (MDE) we are performing a pilot assessment of ongoing contribution of PCBs
from several streams in Back River watershed. Direct measurement of sparingly soluble chemicals like
PCBs in the water phase is challenging due to the ultra-low aqueous concentrations and interference with
colloidal particles. However, the freely dissolved concentrations are indicative of biological uptake,
toxicity, and flux of pollutants between sediments and water column. In addition, the freely dissolved
concentrations provide an indication of potential sources or hot-spots of PCB release in a watershed.
Passive sampling has emerged as an alternative technique to assess freely dissolved concentrations of
hydrophobic chemicals without interference from colloidal particles. In the present project we deployed
polyethylene (PE) passive samplers at 4 tributaries and in the main stem of Back River to measure the
freely-dissolved concentration of PCBs and to understand potential sources of the pollutants. PCB
concentrations ranged from 0.027 – 2.6 ng/L during the deployment period from June 2018 to August
2018, with Bread and Cheese Creek tributary showing the highest dissolved PCB concentrations among
the sampling sites. PCB levels at two locations in Back River itself were 0.99 and 0.56 ng/L. Concentrations
at five out of nine sampling locations exceeded the USEPA Water Quality Criteria of 0.64 ng/L, associated
with a carcinogenicity risk of 10 in a million. These monitoring results will be used to investigate potential
legacy sources of contaminants in upland areas that may be impacting water quality. Benthic organisms
were collected from sediments in the Back River and are being analyzed for PCB concentrations to assess
accumulation at the base of the aquatic food chain. Ongoing analysis of PCBs in sediment porewaters will
be used to obtain greater insight into exchange of PCBs between surface water and porewater and also
allow quantification of bioavailability of PCBs to benthic organisms.
POSTER SESSION
7
Primary Contact: Sarah Lanasa
Email: [email protected]
What’s in your herbicide? Considering the toxicity of herbicide active ingredients, “safeners”,
formulation and photolysis products on non-target algae species
Sarah Lanasa (Towson University), Christopher Salice (Towson University), John Sivey (Towson
University), Dave Cwiertney (University of Iowa), Monica McFadden(University of Iowa), & Mark
Niedzwiecki (Towson University)
Dual II Magnum (DUAL) is an herbicide formulation that is applied to a wide variety of crops including corn
which is a critical crop for much of the eastern and middle United States. When applied before
germination, the active ingredient, S-Metolachlor (S-MET), kills unwanted plants. Interestingly, to protect
crop species from the herbicide, the “safener” Benoxacor (BEN) is added. BEN and other safeners are
considered inert and, therefore, are not regulated nor tested for toxicity. Runoff from agricultural fields
where DUAL has been applied can lead to measurable concentrations of S-MET and BEN in freshwater
systems. Additionally, when the formulation enters water systems and is exposed to UV-light causing its
composition to be altered, forming photolysis transformation products (PTP). While the effects of S-MET
and its PTP on aquatic organisms have been studied, less is known about the effects of BEN and its PTP as
well as DUAL. We conducted a series of 72-hour algae toxicity tests to establish the EC50 (the
concentration causing 50% growth inhibition) of the non-target algae, Raphidocelis subcapitata, for S-
MET, DUAL, BEN and BEN PTP. S-MET was the most toxic followed by DUAL while BEN was less toxic and
its PTP showed little to no toxicity. These data suggest that BEN may provide a “safening” effect to algae
similar to what occurs in terrestrial crop species. Interestingly, when exposed to UV-light (forming PTP),
BEN was degraded or transformed and the toxicity of the photolysis products was less than BEN. The
effects of photolyzed BEN on S-Met toxicity are unknown but we hypothesize that photolyzed BEN would
not provide a safening effect. We are now exploring the PTP of S-MET and DUAL to compare results to
BEN PTP. Results from these studies provide insights into the effects of environmental factors on how
herbicides may impact non-target species under more environmentally relevant conditions.
POSTER SESSION
8
Primary Contact: Erica Loudermilk
Email: [email protected]
Evaluating Effects of Algae-mediated Treatment on Elicitation of Antibiotic Resistance in Wastewater
Treatment Plants
Erica Loudermilk (Department of Environmental Systems and Environment, University of Virginia),
Kassandra Grimes (Department of Environmental Systems and Environment, University of Virginia),
Laura Dunphy (Department of Biomedical Engineering, University of Virginia), Jason Papin (Department
of Biomedical Engineering, University of Virginia), Lisa Colosi (Department of Environmental Systems and
Environment, University of Virginia)
The prevalence of antibiotics downstream of wastewater treatment plants (WWTPs) has resulted in
increased presence of antibiotic resistant bacteria. The addition of a tertiary treatment using algae with
natural photoirradiation has been shown to be beneficial to WWTPs from both a contaminant-removal
and energy-generating perspective as previous LCA studies have shown that the addition of this treatment
could result in a net-energy surplus if the algae is anaerobically digested to produce methane biogas,
which can be converted into bio-electricity for the plant. Algae-based treatment has promising potential
to remove other emerging contaminants, such as antibiotics. This study evaluates the removal of
tetracycline (TET), ciprofloxacin (CIP), and roxithromycin (ROX) by the freshwater alga Scendesmus
dimorphus to assess the effectiveness of algae-based tertiary treatments in mitigating against antibiotic
resistance for three antibiotics commonly present in WWTPs. Adaptive laboratory evolution was
performed using Escherichia coli as a model bacterium. The results show that the algae-treated effluents
exhibited reduced capability to elicit antibiotic resistance in E. coli compared to the untreated effluents.
These results offer a promising approach for using algae-mediated tertiary treatments in WWTPs to
combat antibiotic resistance downstream of the plant.
POSTER SESSION
9
Primary Contact: Taylor Motley
Email: [email protected]
Analysis of physical and biological degradation of PBDEs in historical limed biosolids and THP-AD
treated biosolids
Taylor Motley (University of Maryland, College Park), Sarah Fischer (University of Maryland, College
Park), Birthe Kjellerup (University of Maryland, College Park), Natasha Andrade (University of Maryland,
College Park), and Alba Torrents (University of Maryland, College Park)
Biosolids are rich in recovered nutrients and are often land applied to amend soil. However, biosolids are
known to contain persistent organic pollutants, such as the flame retardant polybrominated diphenyl
ethers (PBDEs). These chemicals were phased out of production and manufacturing in the U.S. by 2013,
but are still ubiquitous in households and buildings. PBDEs are removed during the wastewater treatment
process (WWTP) to varying extents and may persist in the environment. In 2014, a Mid-Atlantic region
WWTP plant implemented thermal hydrolysis process (THP) and anaerobic digestion (AD) in an effort to
produce Class A biosolids. Past work has shown that at this WWTP plant, the total concentration of PBDEs
was lower in THP-AD treated final biosolids samples than in historic lime-stabilized final biosolids samples.
This research further investigates (i) the effect of the THP-AD system on physical and biological
degradation of PBDE-contaminated biosolids during the treatment process, and (ii) trends in falling PBDE
concentrations in historical biosolids samples that may be associated with the chemical’s phase out.
The anaerobic digestion of sludge was modeled on a laboratory scale using bottled anaerobic mesocosms.
Mesocosms were inoculated with either THP-treated or non-THP-treated sludge from the target WWTP
plant. Methods including polymerase chain reaction (PCR), gel electrophoresis, and quantitative PCR were
used to assess the abundance of the anaerobic dehalogenating bacteria Dehalobacter during anaerobic
treatment, post physical treatment.
Analysis of sludge from the AD mesocosms revealed growth of Dehalobacter in digesters fed with both
THP-treated and non-THP-treated sludge. This suggests that ADs fed with both THP and non-THP treated
sludge have the potential to support the biodegradation of PBDEs. PBDE concentrations will be quantified
in limed biosolids sampled from 2011 to 2013, the time period during which PBDEs were phased out of
production in the U.S. These results will address the gap in available PBDE concentration data from this
NRF in an effort to discern if the chemical phase-out or change in solids treatment is responsible for lower
concentrations of PBDEs in Class A biosolids.
POSTER SESSION
10
Primary Contact: Mary Rogers
Email: [email protected]
Characterization and Modeling for Remediation of an Acid Mine Drainage System in Centralia,
Pennsylvania.
Mary Rogers (Towson University), Amy Williams (University of Florida), Kirk Marks (Towson University)
In 1975, 1991, 2001, and 2017-18 (current study), geochemical data on acid mine drainage (AMD) and
associated water and sediments in receiving streams were collected in the Mahanoy Creek Basin, PA, to
evaluate the characteristics and environmental impacts of AMD. The current study focuses on four of
these AMD systems near Centralia, PA, where an underground mine fire has been burning since 1962. The
study has three goals: 1) evaluate potential changes in the water quality of the four AMD sources over the
last 4 decades; 2) determine if the Centralia Mine fire is causing elevated acidity, sulfate, and metal loading
in the Centralia Mine AMD; and 3) investigate possible remediation strategies considering water-quality
characteristics for the AMD. The four AMD systems evaluated are: Centralia Mine/Big Mine Run (CMDS),
Packer5, Girard Mine Seep (Girard), and Bast Mine Overflow (Bast). Water and sediment samples were
collected at the discharge and two or more downstream locations before the AMD entered Mahanoy
Creek. The pH, DO, alkalinity, conductivity, trace elements, major ions, and flow rates were measured.
Although [SO42-] was elevated at all AMD sites, CMDS had elevated [Al] and DO, and low pH and alkalinity
compared to the other discharges, similar to what was reported previously. The continuous burning of
unmined coal inside the Centralia mine could cause warmed air to rise, creating convective circulation
that draws in atmospheric O2 that promotes pyrite oxidation. Owing to atmospheric interaction
downgradient of Girard and Bast, alkalinity decreased while the pH and dissolved O2 increased, indicating
that rapid ingassing of O2 was accompanied by outgassing of CO2. Utilizing technology to promote rapid
CO2 outgassing and increased pH at Packer5 may be a viable remediation strategy. However, because of
its net acidic character, limestone or some other neutralizing agent will be required for treatment of
CMDS. The USGS software PHREEQC will be used to model stream parameters and assess the possibility
of remediation at CMDS and nearby AMD systems.
POSTER SESSION
11
Primary Contact: Alterra Sanchez
Email: [email protected]
Fabricating microplastics with standardized surface area for quantifying the sorption of organic
pollutants
Alterra Sanchez (University of Maryland College Park), Kara Bailey (Micromeritics), Lance Yonkos (University of Maryland College Park), Alba Torrents (University of Maryland College Park)
It is known that organisms ingest microplastics and they may cause deleterious effects, but it is unclear
how large a role microplastics play as a particle versus as an exposure route to organic pollutants. Many
studies have tried to address this issue; however there has been much criticism for environmentally
irrelevant experiments. Additionally, ecologically relevant experiments have not used standardized
microplastic particles and have shown mixed results. The heterogeneity of methods makes comparing
studies challenging, if not impossible. There is a clear need for the development of standardized
methodology for testing the toxicity of microplastics and sorbed pollutants. An integral part of this process
will be the creation of “weathered” microplastics of consistent surface area, as this particle attribute
affects sorption. In order to address this problem, the objective of this study was to develop a
methodology to fabricate irregularly shaped microplastics with a standardized surface area on a mass
basis. Rods of high-density polyethylene and polypropylene were cooled in liquid nitrogen and shaved
with a stainless-steel wood file. The particles were sieved through nine different pore sizes, and then
solvent cleaned. Results will be presented that will show how surface area and surface morphology
changes with particle diameter for all nine sizes, and will include a sorption case study with the
antimicrobials triclocarban and triclosan.
POSTER SESSION
12
Primary Contact: Caitlin Weible
Email: [email protected]
Effects of Dermal Exposure to Perfluroocatesulfonic acid (PFOS) on Brown Anoles (Anolis Sagrei)
Caitlin Weible, Charles Furst, Andew East, and Christopher Salice
Per-and polyfluoroalkyl substances (PFAS) are persistent and abundant environmental contaminants,
creating concern about their potential ecotoxicological effects on humans and wildlife. The goal of this
research was to investigate the uptake and effects of a specific PFAS known as perfluorooctanesulfonic
acid (PFOS), on reptilian species, by means of dermal exposure. To address this research objective, we
maintained brown anoles (Anolis Sagrei) on PFOS-contaminated sand for 90 days. A total of 40 lizards
were utilized for this experiment; 30 animals were reared on PFOS-contaminated sand while 10 served as
controls (no added PFOS). Approximately 1kg of sand was placed in each individual housing container.
Sand was contaminated by adding approximately 5,000 mL of 50:50 mix of methanol and moderately hard
water to 3.277 mg of PFOS. The PFOS, methanol, and water mixture was then slowly poured over 14.4kg
sand with a target concentration that equaled the 75th percentile of soil samples obtained from a
database of PFOS-contaminated sites (227 ug of PFOS per kg soil). Lizards remained under experimental
conditions for either 30, 60, or 90 days. Behavioral observations were taken three times a week and total
mass was measured every week. At the chosen sampling time for a given lizard, liver, skin, and muscle
samples were harvested for chemical analysis (data forthcoming). There were no noticeable behavioral
effects, however, PFOS-treated individuals that were exposed for the entire 90 days generally lost body
mass overall from the beginning to end of the experiment, while the control group generally gained body
mass. Body mass-corrected liver mass also was slightly decreased in PFOS-exposed lizards compared to
the control lizards. To our knowledge this is the only PFOS dermal exposure study involving reptiles and
these data will provide useful insights into ecological risk assessment of ground dwelling species in PFAS-
contaminated habitats.
