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to enlarge photos
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| Netting
fish from an electroshocking boat on the Merrimack River, above
Lawrence, MA. |
A
section of the Merrimack River above Lawrence, MA contained
large carp. |
A
northern pike from the Blackstone River near Manville, RI. |
Largemouth
bass from Merrimack River being measured. |
Collecting
a tissue sample from a largemouth bass. |
Background
Trace elements
and organic compounds found in sediment and fish tissue are indicators
of time-integrated water-quality conditions. Trace elements (such
as mercury, lead, and cadmium) originate from natural sources, but
are redistributed and concentrated by such activities as fossil-fuel
combustion, waste incineration, and various industrial processes.
Trace elements enter river systems through wastewater and storm
runoff discharges. Manmade
organic compounds are introduced into the environment through such
mechanisms as pesticide application, industrial processes, and combustion
of fossil fuels and wood. NAWQA studies typically include an occurrence
survey of trace elements and organic compounds in streambed sediment
and fish tissue to assess the level of contaminants in these media.
Purpose and
study design
An occurrence
survey of trace elements and organic compounds in streambed sediment
and fish tissue in the New England Coastal Basins (NECB) study area
was conducted during 1998 and 1999. Streambed sediment samples were
collected at 14 river sites from Maine to Rhode Island, and fish
tissue samples were collected at 12 of these 14 sites. Sites were
selected over a range of population densities to maximize our understanding
of the effects of urbanization on water quality. (See Table
1
for site characterization). Results from the samples are used to
(1) identify the predominant trace elements and organic compounds
detected in streambed sediment and fish tissue, (2) compare concentrations
of constituents found in this study with those from other studies
and with suggested guidelines for the protection of aquatic wildlife,
and (3) relate concentrations of selected constituents to watershed
features such as land use and population density.
| Study
Location Map |
Data Tables |
click for full view |
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STREAMBED SEDIMENT DATA
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Trace
elements
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Organics
+ PAHs
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FISH
TISSUE DATA
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Trace
elements
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Organics
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General results
The streambed
sediment samples were analyzed for selected chemical compounds,
consisting of trace elements, organochlorine compounds, and semi-volatile
organic compounds. The fish tissue samples were analyzed for trace
elements and organochlorine compounds [see list
of chemical constituents analyzed]. Concentrations of selected
contaminants in both streambed sediment and fish tissue correlated
more strongly with population density than with other watershed
characteristics. Concentrations of many of these constituents in
streambed sediment also were frequently above the consensus-based
Sediment-Quality Guidelines for the protection of wildlife, suggesting
they are a threat to the health of aquatic biota in New England.
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Further
details and conclusions from the study are published in the
report
Trace elements and organic compounds in streambed sediment
and fish tissue of coastal New England streams, 1998-99
(U.S. Geological Survey Water-Resources Investigations Report
02-4179, 30 p. by Ann Chalmers, 2002).
The report
is available in pdf format at: http://water.usgs.gov/pubs/wri/wri024179/.
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Protocols
used for the NECB streambed sediment and fish tissue study
Crawford, J.K.,
and Luoma, S.N., 1993, Guidelines for studies of contaminants in
biological tissues for the National Water-Quality Assessment Program:
U.S. Geological Survey Open-File Report 92-494, 69 p.
Shelton, L.R.,
and Capel, P.D., 1994, Guidelines for collecting and processing
samples of streambed sediment for analysis of trace elements and
organic contaminants for the National Water-Quality Assessment Program:
U.S. Geological Survey Open-File
Report 94-458, 20 p.
Related information
USGS
Guidelines for assessing pesticides in water, bed sediment, and
fish
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