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RESEARCH
My
research encompasses laboratory and field-based applied studies
examining the release of metals from anthropogenic wastes to more
fundamental studies examining the biogeochemical behavior of metals
in lakes and coastal waters. Since arriving at SCSU, I have been
busy developing my laboratory facilities, recruiting students to
conduct research and further developing my research examining contaminant
metals in sediments in the harbors of Long Island Sound. I have
been successful in obtaining CSU research funding to support these
activities. I have also been successful in recruiting undergraduate
students to conduct research in my laboratory. Links are provided
here to view and access copies of my publications, current grants
and examine our laboratory facilities and capabilities. Below are
the research abstracts for the projects undergraduate students have
completed under my supervision at SCSU.
Robert Nicholson (BS Chemistry, 2002) and
I examined the sediment metal contamination in the West River Memorial
Park, New Haven, CT. As part of this study, Kristin
DeRosia (BS Biology, 2002) examined whether the abundance or
diversity of benthic invertebrates was affected by the presence
of contaminant metals in the sediment. Tina Titus
(BS Chemistry, 2004) and I examined the sediment metal contamination
in Bridgeport and New Haven Harbors. A
brief PowerPoint summary of our harbor research can be accessed
here. Matthew Cacopardo (BS Biology,
2004) and I are conducting research examining the accumulation of
metals in oysters in New Haven Harbor. Erica Skirvin
(BS Chemistry, 2005) is currently examining the depositional history
of metals in New Haven harbor sediments. A
brief PowerPoint summary of our oyster and harbor core research
can be accessed here.
>> In the News
Sediment
Metal Contamination in the West River Memorial Park, New Haven
Robert O. Nicholson - Undergraduate Student,
Southern Connecticut State University
Vincent T. Breslin - Assistant Professor,
Dept. of Science Education and Environmental Studies
Southern
Connecticut State University
This
research was designed to examine the spatial distribution of sediment
metal contamination in the West River Memorial Park, New Haven.
Seventeen surface (0-3 cm) sediment samples were collected from
within the river using a ponar grab from a canoe. Sediment samples
were then examined for composition (sand/silt/clay), total organic
matter (loss on ignition) and metals. Copper (Cu), zinc (Zn) and
lead (Pb) contents of the sediments were measured by atomic absorption
spectrophotometry following extraction using a nitric acid-hydrogen
peroxide digest technique. Results show that sediment metal concentrations
were variable and ranged from 43-609 mg/kg for Zn, 34-430 mg/kg
for Pb and from 36-197 mg/kg for Cu. Higher metal concentrations
were associated with finer-grained sediment with high organic matter
contents. Metal concentrations in some locations within the Memorial
Park are 2 to 8 fold greater than metal concentrations expected
from weathering of crustal material within the West River watershed.
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Benthic Invertebrate Distribution
in the West River Memorial Park, New Haven
Kristin L. DeRosia - Undergraduate Student,
Southern Connecticut State University
Vincent T. Breslin - Assistant Professor,
Dept. of Science Education and Environmental Studies
Southern
Connecticut State University
Kristen in the Lab
The West River Memorial Park is a degraded urban marsh habitat close
to downtown New Haven. Research within our laboratory has shown
that some sediment within the marsh is contaminated with metals
of environmental concern (lead, copper and zinc). The present study
was designed to examine whether the abundance or diversity of benthic
invertebrates is affected by the presence of contaminant metals
in the sediment. Seventeen sediment samples were collected from
within the marsh using a ponar grab from a canoe. Sediment samples
were preserved in stained buffered formalin and sieved through a
1.0 mm screen to isolate organisms. Organism classification is being
conducted using appropriate invertebrate keys. Preliminary sorting
has revealed obvious differences in the invertebrate species abundance
and diversity among various sites within the marsh. Ongoing research
is designed to determine if these differences are due to metal contamination
in the sediment or differences in other sediment properties.
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Tissue Metal Contents
of Eastern Oysters (Crassostrea virginica) in New Haven Harbor
Matthew Cacopardo - Undergraduate Student, Biology Department
Vincent T. Breslin - Associate Professor,
Science Education and Environmental Studies
Southern
Connecticut State University
Matthew in the Lab
Eastern oysters (Crassostrea virginica) are known
to concentrate chemicals in their soft tissues and are used for
evaluating physiologic effects of pollutants. Oysters are also important
to the shellfishing industry in Connecticut and are found in areas
throughout New Haven harbor. Previous research in our laboratory
showed sediment metal contamination in the inner reaches of the
harbor surrounding the mouths of the Quinnipiac, Mill and West Rivers.
In contrast, sediment in the leased shellfishing grounds located
in the outer harbor are characterized by fine to coarse-grained
sand with comparably low metal contents. This study is designed
to test the hypothesis that oyster tissue metal contents will vary
relative to the metal contents of the surrounding sediment.
Natural and caged oysters (placed 10-3-03) were collected from various
locations in New Haven harbor including Lighthouse Point, the mouths
of the Mill River and Quinnipiac River and the shellfishing beds
near Savin Rock. Collection sites were selected based on previous
sediment metal analyses at these locations and they are known to
represent a wide range of sediment metal contents. A minimum of
ten oysters of similar size from each location were harvested on
two occasions and depurated in laboratory aquaria in filtered (0.45
µm) water for 48 hours. The soft tissue was removed from each
oyster and the individual oyster tissues were oven dried, acid digested,
and the digests are being analyzed for iron, copper, zinc, nickel,
lead, cadmium and arsenic using flame and graphite furnace atomic
absorption spectrometry.
Metal concentrations in natural and caged oyster tissues measured
in this study were similar. Natural oyster populations sampled on
11-3-03 from three inner and outer harbor locations yielded mean
tissue metal contents ranging from 172 to 368 mg/kg dry wt. for
Fe, 690-860 mg/kg dry wt. for Cu and 0.47-0.91 % dry wt. for Zn.
For caged oysters sampled on 11-21-03, mean oyster tissue metal
contents ranged from 144 mg/kg to 235 mg/kg dry wt. for Fe, 650
to 820 mg/kg dry wt. for Cu and 0.65 to 1.01% dry wt. for Zn. Tissue
metal contents for caged oysters sampled from the Savin Rock and
Lighthouse Point locations were similar to tissue metal contents
for caged oysters sampled from the inner harbor areas (mouths of
Mill and Quinnipiac Rivers) even though they are located in areas
of comparatively lower sediment metal concentrations. Measured oyster
tissue Cu and Zn contents were similar to results of previous studies
for oysters sampled in New Haven harbor and significantly higher
than previously measured oyster tissue metal contents for oysters
collected from Milford and Stratford harbors.
Tissue metal analysis of a second set of caged oysters sampled on
5-10-04 is currently ongoing.
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High
Spatial Resolution Sampling of Metals in the Sediment of Bridgeport
Harbor, CT and New Haven Harbor, CT
Tina
Titus - Undergraduate Student, Biology Department
Vincent
T. Breslin - Associate Professor,
Science Education and Environmental Studies
Southern Connecticut State University
Tina
sampling in Bridgeport Harbor.
New
Haven and Bridgeport Harbors are two of the largest ports of entry
in Connecticut and play pivotal roles in the transportation infrastructure
and future economic development of the state. Both harbors have
been historically characterized by industrial development and are
urbanized throughout their watersheds. Surface (0-6 cm) sediment
samples were collected from thirteen stations in Bridgeport harbor
and 33 stations in New Haven Harbor during 2001-2003 to define a
high-resolution spatial distribution of iron, copper, lead, zinc
and nickel contamination. Sediment metal contents in New Haven harbor
ranged from 6.32 to 405 mg/kg for Cu, 0.77 to 53.0 mg/kg for Ni,
5.83 to 338 mg/kg for Pb, 7.52 to 876 mg/kg for Zn and 0.740 to
2.37 % for Fe. Sediment metal contents in Bridgeport harbor ranged
from 29.1 to 492 mg/kg for Cu, 7.56 to 179 mg/kg for Ni, 22.2 to
337 mg/kg for Pb, 44.6 to 514 mg/kg for Zn and 0.759 to 8.44 % for
Fe. For bot00h harbors, highest sediment metal concentrations were
measured at the inner harbor stations, proximate to the mouths of
the tributary rivers. Sediment metal contents were also highest
in the fine-grained, inner harbor sediment and were lowest in the
coarse-grained sediment located outside the mouth of the harbor
in Long Island Sound. For both harbors, Cu, Zn and Pb contents were
highly correlated with both the iron and % loss on ignition of the
surface sediment. In all areas in both harbors, mean metal concentrations
were higher than their respective crustal abundances. Copper was
found to have the highest calculated enrichment factors for New
Haven and Bridgeport harbors ranging from 35 for the inner harbor
sediment in Bridgeport to 7.6 in sediment for the area surrounding
the breakwaters in New Haven harbor.
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Sediment
Metal Contamination in the Branford River and Harbor
Dr. Vincent T. Breslin; Associate Professor
Dylan Clough, Doug Cucchiarelli, Peter Dart, Charlie Detelich, Sarah
Guancial, Michael Guidone, Donna Lawnsby, Grace Loman, Patrick Loman,
Jon Navarro; Science Education and Environmental Studies
Southern Connecticut State University
The main stem of the Branford River extends about 10.5 miles in
length from just south of Lake Gaillard in North Branford, CT and
ends at the Branford harbor before emptying into Long Island Sound.
Sections of the river watershed are characterized by suburban development
and several point sources of metal contaminants are evident including
marinas, a sewage treatment wastewater outfall and industry. Eighteen
surface sediment samples were collected on July 1, 2004 in the Branford
River south of Interstate 95 and Branford harbor to define a spatial
distribution of sediment metal contamination. Results show that
metal contents of the Branford River and harbor sediment ranged
from 0.7-4.2% for Fe, 21-148 mg/kg for Cu, 3.7-71.7 mg/kg for Cr,
6.5-128 mg/kg for Pb and 35.7-274 mg/kg for Zn. Although sediment
metal concentrations varied greatly, they generally reflected differences
in sediment type, with higher metal concentrations associated with
high loss on ignition, well sorted, fine-grained sediment. Copper,
Zn and to a lesser extent Cr, are correlated with sediment loss
on ignition. In particular, Cu shows a strong linear relationship
with the percentage of organic matter (LOI) found within the Branford
River and harbor sediment. Additionally, sediment Cu and Zn concentrations
co-vary in the river and harbor indicating a similar source. Results
show that sediment Pb, Cu, and Zn contents are elevated above their
respective crustal abundances and are similar or higher than previously
reported NOAA (1994) Branford harbor mean sediment metal concentrations.
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