KAZALCI OKOLJA

Key message
Neutral

In recent years, cadmium and lead concentrations in the kidneys and livers of roe deer has decreased below the level of toxic concentrations that could have a direct adverse effect on the health of the individuals of this species. Nevertheless, cadmium concentrations in the internal organs of roe deer exceed the admissible concentration determined by law in many areas of Slovenia (taking into consideration the suitability for human consumption). Problematic areas in terms of fluoride exposure are the Drava-Ptuj Plain and Haloze, while the Upper Meža Valley is considered problematic due to lead exposure.

 


This indicator shows the exposure of roe deer to metals (lead (Pb), cadmium (Cd)) and fluorides), indicating the level of air and soil pollution in areas of Slovenia, for which relevant data is available, for various periods between 1925 and 2008.

As a bioindicator species, roe deer is suitable for monitoring air and soil pollution with cadmium, lead and fluorides, as it is exposed to a considerable intake of pollutants from its environment due to its specific feeding habits (herbivorous, selective browser with numerous feeding cycles). In addition, territorial behaviour and a very small area of activity of the species guarantee that individual specimens reflect the quality of a spatially limited habitat.


Charts

Figure ZD08-1: Vsebnosti kadmija (mg/kg svežega vzorca; prikazane so mediane s kvartili in ekstremi) v ledvicah srnjadi iz Šaleške doline v letih 1998, 2005 in 2006
Sources:

Pokorny, Zaluberšek, 2007. Srnjad kot bioindikator onesnaženosti okolja. ERICo Velenje.

Show data
nr. of samples median min. value max. value lower quartile upper quartile
1998 49 4.37 0.73 32.6 2.83 6.78
2005 15 5.68 1.76 17 3.02 7.46
2006 8 5.3 2.74 10.6 4.54 9.67
Figure ZD08-2: Vsebnosti svinca (mg/kg svežega vzorca; prikazane so mediane s kvartili in ekstremi) v ledvicah srnjadi iz Šaleške doline v letih 1998, 2005 in 2006
Sources:

Pokorny, Zaluberšek, 2007. Srnjad kot bioindikator onesnaženosti okolja. ERICo Velenje.

Show data
nr. of samples median min. value max. value lower quartile upper quartile
1998 104 0.09 0.01 0.76 0.07 0.13
2005 35 0.08 0.04 1.01 0.07 0.15
2006 17 0.08 0.04 0.38 0.06 0.1
Figure ZD08-3: Trend spreminjanja vsebnosti svinca (mg/kg svežega vzorca; prikazane so mediane s kvartili in ekstremi) v rogovju srnjakov v štirih območjih v Sloveniji
Sources:

Pokorny, Zaluberšek, 2007. Srnjad kot bioindikator onesnaženosti okolja. ERICo Velenje; podatkovne baze ERICo Velenje, 2009.

Show data
nr. of samples median min. value max. value lower quartile upper quartile
Šalek Valley
1960-1969 5 3.79 1.6 7.28 3.56 4.82
1970-1974 4 2.89 1.83 3.67 2.32 3.33
1975-1979 10 1.93 0.83 2.82 1.43 2.35
1980-1984 15 1.56 0.95 4.04 1.05 2.09
1985-1989 19 1.01 0.57 2.2 0.87 1.7
1990-1994 15 1.09 0.53 2 0.7 1.44
1995-1999 25 0.62 0.23 1.51 0.52 0.79
2000-2004 37 0.48 0.06 1.25 0.34 0.81
2005-2007 26 0.23 0.05 1.02 0.14 0.34
Postojnsko (military site Poček)
1970-1974 1 5.08 nr nr nr nr
1975-1979 2 3.86 3.09 4.62 nr nr
1980-1984 5 2.62 1.42 6.77 2.43 2.65
1985-1989 5 1.64 1.1 3.33 1.47 2.3
1990-1994 2 1.83 1.68 1.98 nr nr
1995-1999 1 0.77 nr nr nr nr
2000-2004 9 0.84 0.56 1.9 0.62 1.49
Upper Meža Valley
1920-1929 1 28.3 nr nr nr nr
1930-1939 7 12.1 9.11 37.3 9.47 18.1
1940-1949 1 26.2 nr nr nr nr
1950-1959 1 22.5 nr nr nr nr
1960-1969 3 9.72 9.16 238 nr nr
1970-1979 13 37.4 4.41 504 17 56.7
1980-1989 11 15 6.47 554 7.07 30.2
1990-1999 5 40.4 3.97 97.7 5.87 61.4
2000-2003 6 10.2 2.69 18.6 7.02 13.9
Poljanske Valley
1930-1939 1 2.06 nr nr nr nr
1940-1949 1 3.47 nr nr nr nr
1950-1959 7 1.92 1.09 3.88 1.71 3.41
1960-1969 4 2.14 1.57 4.38 1.76 3.36
1970-1979 7 2.96 1.29 8.2 2.01 4.11
1980-1989 6 3.21 1.9 4.59 2.18 4.26
1990-1999 4 1.78 0.62 2.64 1.12 2.3
2000-2005 6 0.39 0.26 0.88 0.32 0.47
Figure ZD08-4: Trend spreminjanja vsebnosti svinca (mg/kg svežega vzorca; prikazane so mediane s kvartili in ekstremi) v rogovju srnjakov iz Šaleške doline
Sources:

Podatkovne baze ERICo Velenje, 2009.

Show data
nr. of samples median min. value max. value lower quartile upper quartile
1961 1 7.28 nr nr nr nr
1964 2 3.21 1.6 4.82 nr nr
1965 1 3.79 nr nr nr nr
1967 1 3.56 nr nr nr nr
1972 1 2.98 nr nr nr nr
1974 2 3.24 2.8 3.67 nr nr
1975 2 2.29 1.83 2.76 nr nr
1976 2 2.33 1.84 2.82 nr nr
1977 3 2.31 1.78 2.35 nr nr
1978 2 1.43 0.83 2.02 nr nr
1979 2 1.29 1.16 1.43 nr nr
1980 2 1.37 1.05 1.69 nr nr
1981 1 2.09 nr nr nr nr
1982 2 1.83 1.56 2.09 nr nr
1983 6 1.61 1.04 4.04 1.2 3.7
1984 4 1.08 0.95 1.77 0.97 1.47
1985 3 0.9 0.84 1.88 nr nr
1986 2 1.22 0.89 1.55 nr nr
1987 7 1 0.72 2.2 0.75 1.7
1988 5 1.45 0.57 1.9 1.27 1.48
1989 2 1.48 0.87 2.09 nr nr
1990 3 0.77 0.53 1.44 nr nr
1991 5 1.46 0.7 2 1.41 1.87
1992 2 1.04 0.91 1.17 nr nr
1993 3 1.09 0.57 1.2 nr nr
1994 2 0.79 0.66 0.91 nr nr
1995 2 0.68 0.6 0.75 nr nr
1996 6 0.68 0.39 1.51 0.61 1.21
1997 6 0.56 0.44 1.06 0.52 0.66
1998 5 0.62 0.23 1.42 0.48 0.79
1999 6 0.58 0.28 1.32 0.34 1.23
2000 9 0.56 0.2 1.13 0.45 0.87
2001 8 0.54 0.37 1.24 0.42 0.88
2002 6 0.82 0.29 1.25 0.34 1.17
2003 8 0.47 0.34 0.92 0.38 0.55
2004 6 0.22 0.06 0.31 0.15 0.28
2005 10 0.24 0.05 1.02 0.12 0.44
2006 7 0.27 0.22 0.49 0.24 0.34
2007 9 0.14 0.11 0.35 0.13 0.17
Figure ZD08-5: Trend spreminjanje vsebnosti fluoridov (mg/kg svežega vzorca; prikazane so mediane s kvartili in ekstremi) v rogovju srnjakov iz Šaleške doline
Sources:

Podatkovne baze ERICo Velenje, 2009.

Show data
nr. of samples median min. value max. value lower quartile upper quartile
1961 1 310 nr nr nr nr
1964 2 1040 780 1300 nr nr
1965 1 1420 nr nr nr nr
1967 1 1050 nr nr nr nr
1972 1 2230 nr nr nr nr
1974 1 680 nr nr nr nr
1975 2 1105 1060 1150 nr nr
1976 1 1140 nr nr nr nr
1977 3 720 500 1690 nr nr
1978 2 800 620 980 nr nr
1979 2 1165 630 1700 nr nr
1980 2 1335 1040 1630 nr nr
1981 1 1490 nr nr nr nr
1982 2 1280 790 1770 nr nr
1983 5 1420 650 2590 810 2250
1984 4 1555 970 1980 1260 1770
1985 3 1590 920 2040 nr nr
1986 2 1990 1460 2520 nr nr
1987 7 1040 640 2340 670 1890
1988 4 1660 590 2190 895 2155
1989 2 1275 1050 1500 nr nr
1990 3 1040 520 1280 nr nr
1991 5 800 470 2200 470 1660
1992 1 1440 nr nr nr nr
1993 3 1070 350 1900 nr nr
1994 2 1325 960 1690 nr nr
1995 2 550 300 800 nr nr
1996 6 705 380 1500 380 1010
1997 5 580 380 1210 510 780
1998 5 1060 320 1350 970 1180
1999 6 590 430 1140 450 830
2000 7 640 290 1010 600 1000
2001 7 260 110 450 200 400
2002 6 685 320 990 560 970
2003 8 275 130 510 170 405
2004 6 238 184 352 206 331
2005 7 366 241 388 271 384
2006 4 388 292 415 332 410
2007 9 249 192 440 216 271
Figure ZD08-6: Prostorski prikaz stopnje zobne fluoroze (DLI) spodnjih čeljusti odrasle srnjadi, uplenjene v letu 2007 v posameznih loviščih Slovenije, s shematskim prikazom glavnih virov izpustov fluoridov
Sources:

Jelenko in sod., 2009. Čeljusti srnjadi kot kazalec kakovosti življenjskega okolja in pripomoček za upravljanje s populacijami. ERICo Velenje; podatkovne baze ERICo Velenje.


Goals

  • A decrease in the content of metals in all roe deer kidney and liver samples in all age categories in all areas of Slovenia below the permissible value specified in the Rules on contaminants in foodstuffs (Official Gazette of the RS, No. 69/03) by 2015. An exception is cadmium in kidneys, for which the above-stated goal is limited to categories of juveniles and yearlings, while for adult animals, permissible values may be exceeded in <75 % of kidney samples after 2015.
  • A decrease in the content of lead and fluorides in all roe deer antler samples in all areas of Slovenia below the normal value characteristic of non-polluted or moderately polluted areas (lead: 0.5 mg/kg; fluorides: 300 mg/kg) by 2015.
  • A decrease in exposure of roe deer populations to fluorides everywhere in Slovenia by 2015; the goal is measurable as a decrease in the average dental fluorosis rate in adult roe deer in all hunting grounds to the categories of 0 (no fluorosis) or 1 (slight fluorosis).

Due to its specific feeding habits (herbivorous, selective browser with numerous feeding cycles) and sedentary life (very small area of activity), roe deer are exposed to a considerable intake of pollutants from the environment. Consequently, roe deer are a bioindicator species suitable for monitoring air and soil pollution with cadmium, lead and fluorides. Pollutants that enter a roe deer's organism accumulate in its internal organs (cadmium in kidneys and liver, in particular) or bones (lead and fluorides). Some of them cause various histological, anatomical and pathological reactions in certain tissues (e.g. the occurrence of dental fluorosis as a specific indicator of fluoride exposure).

In Slovenia, cadmium is the metal to which roe deer are particularly exposed. Cadmium concentrations in the kidneys and liver reflect the input of this element into the sampled specimen's body during its entire lifespan due to a long-term (several-years) presence of cadmium in the soft tissues of the mammal. Although concentrations of cadmium in the internal organs of roe deer do not reach levels that would directly affect the health of the animals, reproductive potential of individual animals or even sub-populations could be seriously compromised in certain cases. Cadmium concentrations in the kidneys of adult roe deer are high throughout Slovenia. In 1998, cadmium load was highest in the roe deer population of the Pokljuka Plateau (among five studied areas). The highest measured concentration of cadmium in roe deer kidneys in Slovenia was 76.0 mg/kg in the Upper Meža Valley in 1997. Over the recent decade, exposure of roe deer to cadmium has slightly increased (figure ZD08-1).

In contrast, lead concentrations in the internal organs of roe deer were comparable to those in other European countries. Lead concentrations in the liver and kidneys indicate a short-term (several days) exposure to this element, as it tends to be quickly excreted from soft tissues (up to 40 days). In 1998, lead concentrations in the majority of analysed kidney and liver samples throughout Slovenia were below the admissible values determined by law (taking into consideration the suitability for human consumption), while in 2006, none of the analysed samples of internal organs in the Šalek Valley as a selected model area were contaminated with lead (figure ZD08-2).

Due to the properties of roe deer antlers (bone structure), the tendency of lead and fluorides to be permanently deposited in bones and due to the cyclic annual natural growth of antlers, concentrations of lead and fluorides in roe deer antlers reflect exposure of individuals to pollution during the antler growth period within each year, i.e. between November and April. After fluorides have been ingested by roe deer, most are absorbed into the blood (through the stomach and small intestine); after that, fluoride ions (which are extremely negatively charged) bind with calcite ions, which is why 97–99% of absorbed fluorides accumulate in the bone tissues and teeth of the organism, where they cause various pathological changes (e.g. osteofluorosis, dental fluorosis). During antler formation, some of the fluorides that have accumulated in the skeleton are resorbed from the skeleton into the antlers, where they accumulate along with fluoride ions that entered the organism in the same period through food. Similar processes take place in the case of lead.

Since the 1960s, concentrations of lead in roe deer antlers have been showing a steep and continuous decrease in all areas where data is available (Šalek Valley, Postojna Basin, Poljane Valley, Upper Meža Valley), which indicates a decrease in lead contamination of the environment. The combined effect of the introduction of unleaded petrol and the implementation of certain remediation measures at large emission sources contributed to this change (figures ZD08-3 and ZD08-4). An identical trend was determined by analysing roe deer and red deer antlers in other European countries (Germany, Austria, Poland, the Czech Republic, Sweden, United Kingdom). As a rule, contamination of the environment with lead in Slovenia in comparable periods was lower than elsewhere in Europe. An exception is the Upper Meža Valley, where the concentrations of lead in roe deer or red deer antlers in the period of the greatest emissions (1970s, 1980s) were higher than anywhere in Europe measured so far. However, over the recent couple of decades, exposure of roe deer to lead has decreased drastically in this area (figure ZD08-3).

In line with decreasing emissions from large point sources, exposure of roe deer to fluorides has been continuously and noticeably decreasing over the last three decades. In contrast to lead, which is characterised by long-range transmission, fluorides in the environment are of local origin. In the case of the Šalek Valley, concentrations of fluorides in antlers very well reflect the reduction of emissions from the Šoštanj thermal power plant that peaked in the 1980s. Emissions in this area, and consequently the concentrations of fluorides in roe deer antlers, decreased considerably over recent decades and, particularly, after the years of 1995 and 2000 when flue gas scrubbers were installed at the Šoštanj thermal power plant (figure ZD08-5).

A noticeable reduction in roe deer exposure to fluorides has also been confirmed by the decrease in the incidence of dental fluorosis in the recent decade. In the Šalek Valley, its average rate dropped by a whole category in the period 1998–2007, i.e. from moderate to slight. The dental fluorosis rate (DLI: dental lesion index) represents the sum (DLI = 0–30) of visual estimates of change/damage observed in three permanent premolars and three molars (each on the 6-grade scale) of roe deer lower jaws due to exposure to fluorides during the growth and development of teeth, i.e. within the first 18 months of life. Compared to Germany and the Czech Republic, where studying dental fluorosis in roe deer was given the most attention in the past, it was (in general) considerably lower in Slovenia in 2007. The incidence, frequency and intensity of dental fluorosis were very high in the Drava-Ptuj Plain and the Haloze region (i.e. the potential impact area of the Talum aluminium plant in Kidričevo) in 2007 and 2008. Also, dental fluorosis was detected in a significant percentage of jaws in the vicinity of some other local emission sources (the Zasavje region, the Primorska [Littoral] region, the Celje Basin, the Škofja Loka Mountains). Elsewhere in Slovenia, dental fluorosis in roe deer only appears sporadically and is of very low intensity.

 


Methodology

Date of data source summarization