290
A. Gnamus and M. Horvat
factors affecting dry and wet deposition of mercury between sampling at
different locations was minimized. The sampling days were chosen randomly
and were within the same week every season and every year, provided that 5 or
6 days before there was no larger rainfall. At all sampling sites, as well as herbs,
only small twigs and leaves of woody plants positioned in the 0 to 1.8 m sphere
were collected. The samples were transported to the analytical laboratory
within the same day of sample collection. Each composite plant sample was
immediately sorted by species, and fresh weight of each species was
determined. To match the percentage of individual plant species listed in
Table 2, the new composite sample with a defined percentage of individual
species was composed. The samples were not washed or otherwise treated,
since the objective was to determine the whole budget of plant Hg
contamination and to estimate the mercury intake of herbivorous animals as
they consume plants directly - without pretreatment. After weighing, plants
were cut into smaller segments. Composite plant samples were then lyophilized
in a Christ Alpha 1-4 freeze drier at -50°C and approx. 1.5 Pa for 3 days,
starting from the controls to the most contaminated. After lyophilization,
samples were weighed again to determine the wet/dry ratio and ground in a
Brabender mill. During the whole sample preparation procedure, special
precautions were necessary to avoid cross-contamination of samples. Powdered
samples were subsequently transferred into paper bags, packed into plastic
dishes sealed inside polyethylene bags and stored in a refrigerator until further
processing. Moisture content was determined on a separate subaliquot (not the
one taken for analysis) by drying at 85°C for 24 h. All results regarding plant
material are expressed on a dry weight basis.
3.1.3
Animal Samples
Twenty roe deer (Capreolus capreolus L.) of different age and sex were sampled at
random during the hunting seasons 1990 to 1996 (Table 3). Twelve roe deer
originated from localities 1-1 to 1-7 (Fig. 3b: RI-R12) around Idrija, whereas
control roe deer RI-R6 were collected at four non-polluted localities Ctr-2 to Ctr5 elsewhere in Slovenia, and the other two roe deer were collected in the
abandoned Podljubelj mining area (PI:Rl, R2; see Fig. 2). Also tissue samples of
the predator species lynx (Lynx lynx L.; n = 8) and of two wolves (Canis lupus L.)
were collected from the southern to northwestern parts of Slovenia (LI-L6, W2),
some of them relatively close to the contaminated Idrija area (Ll, L2, WI). Tissue
samples were carefully removed from the body and stored in separate
polyethylene bags less than 20 min after the animal died. In the field samples
were labelled, placed into polyethylene bags and temporarily stored at +4 °C in a
refrigerator, transferred to the laboratory and deep frozen (-20°C). Before
further processing, brain, eyes, pituitary, pineal gland, suprarenal gland,
masseter muscle, lungs, liver, spleen, kidney and fur were dissected. Twentyfive different roe deer tissues were selected to establish Hg distribution and
accumulation in the body:
A. Gnamus and M. Horvat
factors affecting dry and wet deposition of mercury between sampling at
different locations was minimized. The sampling days were chosen randomly
and were within the same week every season and every year, provided that 5 or
6 days before there was no larger rainfall. At all sampling sites, as well as herbs,
only small twigs and leaves of woody plants positioned in the 0 to 1.8 m sphere
were collected. The samples were transported to the analytical laboratory
within the same day of sample collection. Each composite plant sample was
immediately sorted by species, and fresh weight of each species was
determined. To match the percentage of individual plant species listed in
Table 2, the new composite sample with a defined percentage of individual
species was composed. The samples were not washed or otherwise treated,
since the objective was to determine the whole budget of plant Hg
contamination and to estimate the mercury intake of herbivorous animals as
they consume plants directly - without pretreatment. After weighing, plants
were cut into smaller segments. Composite plant samples were then lyophilized
in a Christ Alpha 1-4 freeze drier at -50°C and approx. 1.5 Pa for 3 days,
starting from the controls to the most contaminated. After lyophilization,
samples were weighed again to determine the wet/dry ratio and ground in a
Brabender mill. During the whole sample preparation procedure, special
precautions were necessary to avoid cross-contamination of samples. Powdered
samples were subsequently transferred into paper bags, packed into plastic
dishes sealed inside polyethylene bags and stored in a refrigerator until further
processing. Moisture content was determined on a separate subaliquot (not the
one taken for analysis) by drying at 85°C for 24 h. All results regarding plant
material are expressed on a dry weight basis.
3.1.3
Animal Samples
Twenty roe deer (Capreolus capreolus L.) of different age and sex were sampled at
random during the hunting seasons 1990 to 1996 (Table 3). Twelve roe deer
originated from localities 1-1 to 1-7 (Fig. 3b: RI-R12) around Idrija, whereas
control roe deer RI-R6 were collected at four non-polluted localities Ctr-2 to Ctr5 elsewhere in Slovenia, and the other two roe deer were collected in the
abandoned Podljubelj mining area (PI:Rl, R2; see Fig. 2). Also tissue samples of
the predator species lynx (Lynx lynx L.; n = 8) and of two wolves (Canis lupus L.)
were collected from the southern to northwestern parts of Slovenia (LI-L6, W2),
some of them relatively close to the contaminated Idrija area (Ll, L2, WI). Tissue
samples were carefully removed from the body and stored in separate
polyethylene bags less than 20 min after the animal died. In the field samples
were labelled, placed into polyethylene bags and temporarily stored at +4 °C in a
refrigerator, transferred to the laboratory and deep frozen (-20°C). Before
further processing, brain, eyes, pituitary, pineal gland, suprarenal gland,
masseter muscle, lungs, liver, spleen, kidney and fur were dissected. Twentyfive different roe deer tissues were selected to establish Hg distribution and
accumulation in the body: