Background levels of toxic substances
Introduction
This Appendix is intended to provide some background
information on concentrations found for some of
the toxic substances considered in this report during
systematic surveys undertaken in recent years. Other
information on "typical" concentrations found for many contaminants
is given in the individual profiles in Appendices
B and C. However, this summary is not exhaustive and readers are
advised to contact the Environment Agency/SEPA area
or regional offices for advice on more recent survey
information.
Two major reviews: 'National
Monitoring Programme. Survey of the Quality of UK
Coastal Waters'
(prepared by the Marine Pollution Monitoring Management
Group) (MPMMG 1998) and 'Pesticides in the Aquatic Environment, 1995' (prepared by the National Rivers Authority)
(TAPS 1995) have been published which present summary
information on the concentrations of various toxic
chemicals in UK estuarine and coastal waters.
The National Monitoring Programme (NMP) was initiated
in the late 1980s to co-ordinate marine monitoring
in the UK between various regulatory organisations
(and their predecessors). The results from the first
phase of the NMP was intended to establish the spatial
distribution of contaminants in UK marine waters
and to define their biological status. A survey
of 87 estuarine, intermediate and offshore sites
was carried out between 1992 and 1995 to determine
the distribution of contaminants (including metals
and organic substances) in a range of matrices (water,
sediments, shellfish and fish).
The report 'Pesticides
in the Aquatic Environment, 1995'
(prepared by the National Rivers Authority) (TAPS
1995) presents information on the concentration
of various toxic substances in the estuarine and
coastal waters of England and Wales. In 1995, the
NRA monitored 101 pesticides and recorded almost
35,000 results in estuaries and coastal waters from
413 sites (TAPS 1995). The data were recorded as
the number of samples that exceeded 0.1 mg l-1,
with no further information available on the highest
concentrations reported.
A more recent report has been published (Environment
Agency 1999) and readers are referred to this document
for updated information on pesticides contamination
of estuary and coastal waters.
Water Column Concentrations
Sediment Concentrations
Biota Concentrations
References
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