Title:
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A comparison of the pollution record of South Merseyside from sediment cores taken from the estuary and a small lake
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The ability to assess the contamination of sediments in estuaries and lakes is extremely
important. This is because of various factors, both natural (tidal action, chemical
remobilisation) and anthropogenic (e.g. building work), that lead to the disturbance of
the sediment can result in the remobilisation or resuspension of the pollutants and, if
high levels of pollutants are present in ,a region, they can be responsible for a number of
health impacts on the local population. The use of sediment cores to investigate the
pollution levels in the sediment is a relatively easy method of assessing contamination.
The main aims of this study were to investigate pollution in saltmarsh, intertidal and lake
sediment cores taken from the South Liverpool area and to attempt to distinguish
different pollutant transport pathways between cores.
This was done using sediment cores taken from a saltmarsh, intertidal area and lake in
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South Merseyside and measuring the heavy metal and persistent organic pollutant (P AH
and PCB) content using a variety of methods including; X-Ray Fluorescence,
Environmental Magnetism, Gas ChromatographylMass Spectrometry and Flame Atomic
Absorption Spectrometry.
The results showed that, although the pollution input to the region has reduced over the
last 30 years, there are still high levels of certain chemicals (including lead, mercury and
PCBs) in the environment. The concentrations of the main pollutants (Pb, Zn, Hg, Cd,
PCBs and PARs) are above guideline levels that are considered dangerous to aquatic
organisms, however with the exception of Cd at Speke, none of the metals are present at
a concentration that would be considered dangerous to human health. The main source
of pollution to the saltmarsh is aquatic, whilst the main input to the lake core is from
atmospheric deposition.
From the data acquired for this project it would appear that the core from the Speke Hall
Lake location provides a more accurate record of the pollution history of the area than
those from the more dynamic saltmarsh environment.
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