Fróðskaparrit - 31.12.2000, Blaðsíða 148

152
INDIVIDUAL ANALYSES OF MERCURY AND ORGANOCHLORINES
IN MARINE MAMMALS FORM THE FAROEISLANDS
dride reduction AAS (Perkin Elmer 2380,
AOAC (90) 974s264, mod DIN.). The
analyses were done on fresh, but previous-
ly frozen, material. The sample was dehy-
drated at 105°C until a stable dry mass was
obtained. This procedure facilitates com-
parison with other studies, and also facili-
tates the comparison of the results within
the present study because the mercury con-
centration may then be expressed on a dry
mass basis. The reason that a dry mass ba-
sis is preferred for comparison is that the
major part of the mercury is confined to the
protein-rich part of the muscle and a sam-
ple with a high water (blood) content has
markedly lower mercury content per unit of
sample. Fifteen percent of the samples
were analysed in duplicate for quality con-
trol.
Qrganochlorines
When preparing the blubber samples for
analysis, the part of the tissue that had been
in contact with the plastic wrapping was cut
away, and the material intended for analy-
sis was put into heat-treated glass jars. The
analyses for organochlorines were done on
blubber tissue, at Le Centre de Toxicologie
du Quebec, CTQ, Canada. Aliquots of tis-
sue where homogenised in the presence of
methylene chloride, anhydrous sodium sul-
phate and an internal standard, PCB # 198.
Determination of lipid content: An
aliquot of the methylene chloride extract
Table 7. The resultsfor pesticides in grey seal blubber, in pg/kg lipid. The results are shown with mean (bold)
minimum and maximum valuesfor the groups ofadult and juvenile, females and males.
Talva 7. Skaðakyktaeitur í kópi er víst í pg/kg av feitti. Urslitini eru víst sum miðalvirði við standardfrávikum
(við feitari skrift), eins og lægsta og hægsta virði fyri teir fýra undirbólkarnar av opnum og brimlum, hvølpum
og vaksnum er víst.
# Ref. p.p'- DDD P.P’- DDT PP’- DDE Sum Chlor- danes 15-HCH alpha- chlor dane gamma- chlor dane cis- • nona chlor Hexa- chloro- benzene Mirex Oxy chlor dane Trans- nona chlor
juv. females nd 180 951 533 nd nd 5 25 26 23 276 227
std. dev. na 45 273 107 nd 3 1 8 32 10 76 60
N = nd 117 717 358 nd nd 4 12 6 8 148 120
10 nd 262 1609 687 5 8 7 40 90 42 356 319
ad. females nd 159 544 348 nd 5 3 25 29 50 155 160
std. dev. na 72 229 142 na 5 2 8 34 10 71 69
N = nd 67 153 160 nd nd nd 15 2 34 46 92
11 nd 280 871 602 nd 13 6 35 115 66 291 314
juv. males nd 290 1383 674 nd 5 5 37 23 30 350 277
std. dev. na 68 394 249 na 6 1 9 22 22 195 67
N = nd 196 1024 384 nd nd 4 23 6 9 150 195
7 nd 385 1912 1049 7 13 6 53 72 72 694 390
ad. males 60 771 3033 1284 nd 10 3 71 14 358 652 548
std. dev. 19 506 1293 505 na 17 3 30 9 324 280 244
N = 43 380 2264 839 nd nd nd 41 6 126 488 300
3 81 1343 4525 1833 6 30 6 101 24 729 976 787