D. Minchin et al., BIOLOGICAL INDICATORS USED TO MAP ORGANOTIN CONTAMINATION FROM A FISHING PORT, KILLYBEGS, IRELAND, Marine pollution bulletin, 34(4), 1997, pp. 235-243
Contamination by organotins in areas of aquaculture and small boat act
ivity about Ireland has generally decreased since legislation was intr
oduced in 1987, but in many port areas contamination increased, The fi
shing port of Killybegs lies within a small sheltered inlet in Donegal
Bay on the N-W Irish coast and is the main source of contamination fo
r several kilometers, This area has been studied using imposer of dogw
helks, Nucella lapillus, since 1987, Dogwhelks are particularly sensit
ive to TBT and have become extinct within the Harbour, and remaining p
opulations near the Harbour entrance are likely to die-out, Periwinkle
s, Littorina littorea, are less affected by TBT and have a condition,
intersex, which was used to determine the relative levels of contamina
tion within the Harbour in areas where dogwhelks no longer exist, Both
indicator species compliment each other; but periwinkles, useful for
areas where there is high contamination, can provide some unexpected r
esults in areas of low contamination, For such areas dogwhelks are bet
ter indicators, Imposer and intersex values decline with distance from
source; low levels of contamination were found 12 km from Killybegs p
ort. Decrease of these biological indices with distance from source wa
s generally consistent with TBT body burdens, Fishing vessels that are
greater than 25 m are permitted to use organotin antifoulant paints a
nd high levels of contamination are expected to remain in the immediat
e area of the Harbour for some years even if its use is discontinued.
(C) 1997 Elsevier Science Ltd.