Fróðskaparrit - 01.07.2004, Blaðsíða 127

KYKSILVUR í FØROYUM - EIN GJØGNUMGONGD AV TØKUM DÁTUM
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Fig. 18 Mercury in grey seal muscle,
in mg/kg, in samples taken around
the Faroe Islands 1993-1995. The
regression line based on thefemale
results is sliown (Adaptedfrom Dam
et. al„ 2001).
were however much lower than in the
Faroese ones, with concentration of 0,5
mg/kg (range 0,3-1,1) and 2,5 mg/kg
(range 0,9-4,1) respectively.
Discussion
In the present paper the available informa-
tion on mercury concentration in the
Faroese environment is reviewed, and mer-
cury concentration from matrices in the at-
mospheric compartment, the terrestrial
freshwater compartment and the marine en-
vironment has been described. When avail-
able, data on similar matrices in neighbour
countries or in countries from which com-
parable data has been recently published,
are discussed for comparison. The overall
purpose of the review is to gather mercury
data so as to be able to discern where ele-
vated concentrations occur and if possible
also to elucidate the question of sources.
The studies undertaken on atmospheric
transport of mercury to the Faroes and the
results of the European moss metal survey
do not indicate elevated mercury input to
the terrestrial environment above what is
seen in for instance the Scandinavian coun-
tries. This may be supported also by obser-
vations that mercury in sheep was low, and
not detected at 0,02 mg/kg. A bit puzzling
then, is the finding of somewhat elevated
mercury concentrations in hare livers, as
these two grazers would have the same
food source.
Also, the analyses of mercury in soil
(incl. peat) and freshwater físh like Artic
char in particular, do indicate high concen-
trations of mercury in the soil and in the
freshwater system. It should be recalled in
this context though, that concentration is
not just a question of the amount of soluble
material that is put into a system, it is just
as much a question of what volume this
system has available for diluting the mater-
ial. This must be kept in mind when evalu-
ating the concentration of mercury in the
Leynavatn Arctic char samples, but it may
also be of relevance to the mercury in soil
and sediment concentration, such that low
yearly increments in “dilution mass” will
result in relatively high concentrations even
when the deposit or intake was not elevat-
ed. Also, it may be speculated whether the
moderate temperatures and high humidity