Fróðskaparrit - 31.12.2000, Page 168

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INDIVIDUAL ANALYSES OF MERCURY AND ORGANOCHLORINES
IN MARINE MAMMALS FORM THE FAROEISLANDS
year-old female and two males, a one-year-
old and a thirteen-year-old, respectively. In
the white-sided dolphin adult males, the
concentration of JJ-HCH was about 100
pg/kg lipid, which is approximately triple
the concentration in the adult male pilot
whales.
In the white-sided dolphin female group,
there was a clear correlation (Pearson cor-
relation coefficient >0.90) between the
organochlorines occurring at the highest
concentration level, represented by p,p’-
DDE, CB 153, trans-nonachlor, and Parlar
50. Such correlation, however, was absent
in the male group. In the pilot whale fe-
male group, there was a clear correlation
between Parlar 50 and CB 153, but not to
other compounds, except the other
toxaphene constituents Parlar 26 and Parlar
62. Neither was there any clear correlation
between CB 153 and ’-DDE nor CB 153
and trans-nonachlor. There was, however,
correlation between p,p’-DDE and trans-
nonachlor. In the female seals, the picture
was opposite with no strong correlation be-
tween toxaphene and PCB, but correlation
between CB 153 and p,p’-DDE. In the
male seal group, there was also a strong
correlation between CB 153 and trans-
nonachlor.
From these observations, it is obvious
that there are no straightforward correla-
tions between the relative concentrations of
the various POPs among the various
species. Correlation analyses failed to in-
dicate any pattern in pollutant concentra-
tions other than clear-cut correlations be-
tween isomers, metabolites, and congeners
of compounds. For pilot whales, for in-
stance, the most persistent CB congener,
CB 153, was highly correlated to CB 138
with a Pearson correlation coefficient equal
to 0.997. The other congeners also corre-
lated to each other, except the lower chlori-
nated CB 28, which was not or more weak-
ly correlated to the other congeners with
correlation coefficients in the range 0.21 to
0.68 for the pilot whale males and 0.51 to
0.82 for the pilot whale females.
The compounds in the DDT group corre-
lated to each other with the highest correla-
tion between the ortho,para substituted
compounds (> 0.94 in the pilot whales) and
more modestly between the para,para com-
pounds (in the range 0.82 to 0.89 for the pi-
lot whales). In the white-sided dolphins,
the highest correlation was between the
o,p’-DDE and the two DDD isomers, o,p’-
DDD and p,p ’-DDD, with correlation coef-
ficients of 0.996 and 0.993 in the females
and somewhat weaker 0.968 and 0.971 in
the males. The correlation between espe-
cially p,p'-DDE and p,p’-DDT and p,p’-
DDD was much weaker in the male dol-
phins than in the female dolphins with co-
efficients of correlation of 0.643 and 0.678,
respectively, in the males and 0.970 and
0.954, respectively, in the females.
For the male dolphins, the correlation be-
tween Mirex and p,p’-DDE was clear
(0.930), but not for the females (0.206).
The same was also true for the seals; for the
females there was no particular correlation
between Mirex and p,p ’-DDE, but with the
male seals there was high correlation be-
tween Mirex and p,p’-DDE (0.947) and
also very markedly with p,p ’-DDT (0.992).
In pilot whales, the highest Pearson corre-