Fróðskaparrit - 01.01.1998, Page 71

ORGANOTIN OGIMPOSEX í STRANDARØKINUM í FØROYUM
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gian waters (Knutzen el al., 1995).
Seasonal fluctuations in TBT concentra-
tions were observed in mussels from the
Oslofjord in Norway (Følsvik, 1997) with
minimum concentrations found in early
winter (December) and a maximum in ear-
ly spring (March). The mussels analysed
from the Faroe Islands were collected in
February and March and should, based on
the Norwegian results, be near their maxi-
mum. The degree of pollution, indicated by
the TBT levels found in mussels from the
Faroe Islands, seems thus to be somewhat
lower than in Norwegian coastal areas.
At four of the stations, concentrations of
organotin compounds were determined in
both dogwhelks and common mussels. A
piot of the results shows a relation between
the concentrations in the two species, fig. 5.
Nucella may feed on juvenile Mytilus, but
this is hardly of any relevance in the present
study. The primary reason is that the sam-
pling of the two species were normally not
done at one and the same spot, hence the
mussels were not within the foraging range
2 4 6 8 10 12 14
Concentration of TBT, ng Sn/g d.w., in dogwhelks
Fig. 5. Concentrations ofTBT (ng Sn g1 d.w.) in
common mussel (Mytilus edulis) as a function ofthe
concentrations ofTBT (ng Sn g1 d.w.) in dogwhelks
(Nucella lapillus) from four stations.
Mynd 5. Innihald av tributyltin, TBT, (ng Sn g'1 t.e.) í
kræklingi (Mytilus edulis) er víst sum funktión av
innihaldinum av TBT (ng Sn g'1 d.w.) í purpur-
kúvingum (Nucella lapillus) á fýra ymiskum støðum.
of the dogwhelks, and secondly, the size of
the analyses mussels were larger than ex-
pected for prey items of Nucella. The rela-
tion between the concentration of TBT in
the two species, fig. 5, is therefore probably
reflecting the level of TBT contamination
in the stations though so, that the common
Station Nr. Date Count Length, mm % d.w. MBT DBT TBT
Tórshavn
Sandagerði lb 29.02.96 67 40 15 20 72 372
estmanna 3 17.02.96 34 73 17 <12 13 49
rongisvágsfjørður
Kolatoftir 4a 31.01.96 40 59 16 <12 25 132
Hvítanes 4b 31.01.96 47 59 17 13 23 87
Klaksvík, Strond 5 21.03.96 30 68 18 <12 36 65
Sólsoy, Víkin 6a 05.03.96 65 44 15 <12 72 80
Skálafjørður
Langanes 7a 01.03.96 42 56 15 <12 26 101
Fish farm “Bakkafrost” 7b 29.02.96 35 52 20 <12 19 100
Tab. 3. Levels of organotin compounds in common mussel (Mytilus edulis) from the Faroe Islands, levels given in
ng Sn g-‘ d.w.
alva 3. Innihald av organotin evnum í kræklingi (Mytilus edulis) úr Føroyum, nøgdir eru vístar sum ng Sn g'1 t.e.