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Accumulation of selected metals pollution in aquatic ecosystems in the Smeda

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Accumulation of selected metals

pollution in aquatic ecosystems in the
Smeda river (Czech republic)
A R T I C L E

Petr Dvořák 1, Jaroslav Andreji 2, Ivana Faltová Leitmanová 3,

Filip Petrách 4, Jan Mráz 1
1 University of South Bohemia in Ceske Budejovice, Faculty of Fisheries and Protection of Waters,
South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Institute of
Aquaculture and Protection of waters, Ceske Budejovice, Czech Republic;
2 Department of Poultry Science and Small Farm Animals, Slovak University of Agriculture, Nitra,
Slovak Republic;
3 Faculty of Economics, University of South Bohemia, Ceske Budejovice, Czech Republic;
4 Faculty of Corporate Strategy, Institute of Technology and Business in Ceske Budejovice, Ceske
Budejovice, Czech Republic

Correspondence to: Ing. Petr Dvořák, PhD.

University of South Bohemia in Ceske Budejovice, Faculty of Fisheries and Protec-
tion of Waters, South Bohemian Research Center of Aquaculture and Biodiversity
of Hydrocenoses, Institute of Aquaculture and Protection of waters
Na Sádkách 1780, 370 05 České Budějovice, Czech Republic.
tel: +420 38777 4648; e-mail: dvorakp@frov.jcu.cz
O R I G I N A L

Submitted: 2018-06-20 Accepted: 2018-09-17 Published online: 2018-11-15

Key words: toxic metal; fish; ecological risk; Smeda river; consumers

Neuroendocrinol Lett 2018; 39(5):380–384 PMID: 30664343 NEL390518A04 © 2018 Neuroendocrinology Letters • www.nel.edu

Abstract OBJECTIVES: Biomonitoring of some slelected heavy metals in the Smeda river
(Czech Republic) was carried out during 2015–2016 to assess the extent of
environmental pollution. Attempts were also made to map the intensity of bioac-
cumulation in brown trout which was used as an indicator species. Monitoring of
the environmental pollution of the Smeda river was carried in 2016.
DESIGN: Concentrations of some heavy metals i.e. Mercury (Hg), Lead (Pb),
Cadmium (Cd) and Cobalt (Co) were quantified in the fish muscles. Correlations
(Pearsons, 2-tailed) among selected metals with some morphometric parameters
(standard length and total weight) in brown trout (Salmo trutta fario) were also
examined.
RESULTS: Results showed a significant positive correlation between concentra-
tions of Hg, Pb (group-I) and Pb, Cd (group-II) with the muscles and age of fishes
(p<0.05). The groups of heavy metals i.e. group-I (Hg and Pb) and group-II (Pb
and Cd) were purposively synthesized for better inference of the data since Pb
formed significant (p<0.05) but distinct positive correlations with Hg and Cd. The
contents of the analyzed metals in brown trout muscles were low Hg 0.06–0.5; Pb
0.01–0.3; Cd 0.01–0.04 and Co 0.01–0.03 mg.kg–1 wet weight basis and did not
exceed the values of limits admissible in the Codex Alimentarius for safe human
consumption except in the case of Hg which is little vulnerable to reach critical limit.
CONCLUSIONS: The contents of the analyzed metals in Brown trout muscles were
lower at monitoring sites and did not exceed the values of limits admissible in the
Czech Republic. Potential ecological risk analysis of toxic metals concentrations
in sediments suggested only two sites (2 and 3) with elevated values that posed a

To cite this article: Neuroendocrinol Lett 2018; 39(5):380–384

 Ecological risk analysis of toxic metals concentrations in the Smeda river
middle environmental risks. Strict periodical monitor- polluted with Bogatynia lignite industry sewage (Koslor
ing of Hg levels in the selected stretches of the River et al. 2015).
Smeda is recommended. The aim of this study was to investigate the level
of contaminants (Hg, Pb, Cd and Co) in brown trout
INTRODUCTION (Salmo trutta morpha fario) from the upper course of
the Smeda river (Czech Republic) and their compari-
Many natural rivers have been exposed to metal con- son with permitted limits for safe consumption, defined
tamination from anthropogenic sources. Industrial and in the Commission Regulations No. 1881/2006 and
agricultural progress has resulted in increasing pollu- 629/2008. Furthermore, correlations among the metal
tion by heavy metals representing a significant envi- concentrations, standard length, total weight and age of
ronmental hazard (Maceda-Veiga et al. 2012). Toxic fish were analysed. These results were juxtaposed with
metals may be released into a water column in response similar analyses of water samples collected from the
to hydrological changes during floods (Agarwal et al. same sites, which allowed us to determine the elemental
2005) and become potential threat to invertebrates, composition.
fish and humans (Arantes et al. 2016; Smylie et al. 2016;
Hope 2006). The pollution monitoring using bioac- MATERIALS AND METHODS
cumulators is one of the methods for the evaluation
of xenobiotic levels (Dvorak et al. 2014; Remon et al. Samples of water, sediments were collected in 2016
2013). Although, effects of toxic metals may as well be year from 10 sites of the Smeda river (Czech Republic)
detected on land as a result of their bioaccumulation (Figure 1). Brown trout by was colleted by electrofish-
and bioconcentration in the food chain (Dvorak et al. ing (220–250 V, 1.5–2.5 A, 63 Hz) from same sites and
2015; Haluzová et al. 2010). Fish consumption has posi- time period.
tive health benefits but also brings higher risks of intake Fish (n=100) were evaluated by standard methods
of heavy metals for humans. Garzon et al. (2016) evalu- used in ichthyology (standard length – SL and total
ating from an economic perspective how important are weight – TW measurements, age determination by
these health and biodiversity components for those in scales). Upon recording the biometric data (Table 2),
the fish value chain, from fishermen to final consumers. samples of fish muscles were obtained from the dorsal
Smeda river was chosen because it is polluted by the part of their body. The collected tissue and sediment
textile and glass industries that are a major source of samples were kept at –18°C.
trace elements and other pollutants that affect the devel- The total mercury content was determined directly
opment of ecosystems (Koslor et al. 2015; Maiti 2007). in the sample units by the selective mercury analyser
The Smeda river was known by presence of dams, as a (Advanced mercury analyser, AMA-254) based on
source of technological water for small glass and textil atomic absorption spectroscopy (AAS wavelenght
factories. This way they got trace elements and other 253.65 nm; limit of quantiy 0.002 mg.kg–1). Other toxic
pollutants influencing ecosystem development into the metals (Pb, Cd and Co) were measured by the means
river (Maiti 2007). The Smeda River (Luzicka Nisa) of electrothermal (flameless) atomic absorption spec-
belongs to the most contaminated rivers in the Poland, trometry with Zeeman background correction (graph-
ite furnace atomic absorption spektrometry (GF-AAS,
SpectrAA 220Z, Varian) after microwave mineralisa-
tion of the samples (EN13 804, 13805 and 14084). The
concentrations of all target analytes in samples were
determined and expressed in wet weight (w.w.) and
compared with the Czech nationwide regulation no.
305/2004 (Czech Republic, 2004) setting the maximum
residue levels in foodstuff.
For statistical analysis, the Anova One-Way test,
Multiple Range test (LSD method), Kruskal-Wallis test,
and Linear Model of Simple Regression (least squares
fit) were used together with the computer program Stat-
graphics Centurion 18 Profesional.

RESULTS AND DISCUSIONS

Content of analysed metals in fish
Hg – detected values varied from 0.06 to 0.49 mg.kg–1 w.
w. (Table 1), with higher mean concentrations at lower
river sites (sites 1–3) and lowest mean concentrations at
Fig. 1. The site of sample collection from the Smeda river higher situated sites (sites 8–10). Statistical significant

Neuroendocrinology Letters Vol. 39 No.5 2018 • Article available online: www.nel.edu 381
 Petr Dvořák, Jaroslav Andreji, Ivana Faltová Leitmanová, Filip Petrách, Jan Mráz

Tab. 1. Mean concentration of analyzed metals, water and sediment.

water (mg/l) sediment (mg/kg dry mass)
Site
Hg Pb Cd Co Hg Pb Cd Co
1 0.05 0.06 <0.05 <0.05 0.32 0.29 <0.05 <0.05
2 0.05 0.21 <0.05 <0.05 0.42 0.29 <0.05 <0.05
3 0.05 0.16 <0.05 <0.05 0.41 0.33 <0.05 <0.05
4 0.05 0.08 <0.05 <0.05 0.27 0.19 <0.05 <0.05
5 <0.05 0.06 <0.05 <0.05 0.24 0.21 b. d. <0.05
6 <0.05 0.07 <0.05 <0.05 0.13 0.14 b. d. <0.05
7 <0.05 0.05 b. d. <0.05 0.09 0.1 <0.05 <0.05
8 <0.05 0.06 b. d. b. d. 0.06 0.13 <0.05 <0.05
9 <0.05 <0.05 <0.05 b. d. 0.08 0.08 b. d. b. d.
10 <0.05 <0.05 <0.05 b. d. 0.06 0.13 b. d. b. d.

b.d. – below detectable limit

Tab. 2. Characteristics of analysed fish Tab. 3. Content of selected metals.

Site N Age SL (mm) BW (g) Site Hg Pb Cd Co
1 10 3.4±0.5 221.7±18.6 200.1±46.0 1 0.35e±0.06 0.03a±0.01 0.01a±0.00 0.01bc±0.01
(3–4) (200–254) (159–284) (0.26–0.44) (0.01–0.04) (0.01–0.02) (0.01–0.02)
2 10 3.1±0.3 205.4±14.4 163.9±30.1 2 0.34e±0.09 0.20e±0.06 0.02ab±0.01 0.01bc±0.01
(3–4) (184–240) (139–246) (0.20–0.50) (0.11–0.30) (0.01–0.04) (0.00–0.03)
3 10 3.1±0.3 207.9±11.8 167.8±20.4 3 0.34e±0.05 0.24f±0.04 0.03b±0.01 0.01c±0.00
(3–4) (195–233) (147–213) (0.28–0.42) (0.18–0.29) (0.02–0.04) (0.01–0.02)
4 10 3.2±0.4 210.4±17.1 178.7±34.1 4 0.21cd±0.06 0.14d±0.05 0.01ab±0.00 0.01ab±0.00
(3–4) (189–241) (140–254) (0.10–0.31) (0.08–0.21) (0.01–0.02) (0.00–0.01)
5 10 3.3±0.7 224.1±25.2 207.2±57.4 5 0.22d±0.11 0.09bc±0.03 0.03ab±0.02 0.01ab±0.00
(3–5) (194–284) (159–349) (0,08–0.41) (0.04–0.13) (0.01–0.09) (0.00–0.01)
6 10 3.1±0.3 210.4±13.7 178.6±31.8 6 0.19bcd±0.08 0.13cd±0.05 0.01ab±0.00 0.01ab±0.00
(3–4) (195–241) (145–254) (0.09–0.36) (0.06–0.21) (0.01–0.02) (0.00–0.01)
7 10 3.0±0.0 203.0±12.0 163.7±17.7 7 0.16abc±0.04 0.15d±0.04 0.02ab±0.01 0.02c±0.03
(3) (186–221) (145–198) (0.09–0.22) (0.08–0.21) (0.01–0.03) (0.01–0.09)
8 10 2.8±0.4 190.0±10.9 151.6±10.5 8 0.11a±0.04 0.13d±0.04 0.03ab±0.05 0.01ab±0.00
(2–3) (168–206) (136–167) (0.07–0.19) (0.06–0.20) (0.01–0.15) (0.00–0.07)
9 10 2.9±0.3 196.3±14.6 158.8±12.8 9 0.13ab±0.05 0.09b±0.03 0.02ab±0.01 0.00a±0.00
(2–3) (169–214) (138–180) (0.06–0.21) (0.05–0.16) (0.01–0.03) (0.00–0.01)
10 10 3.0±0.0 198.5±12.3 161.3±10.3 10 0.11a±0.04 0.12bcd±0.04 0.02ab±0.00 0.00a±0.00
(3) (178–218) (144–179) (0.06–0.17) (0.08–0.21) (0.02–0.02) (0.00–0.01)

(mean ± SD and minimum – maximum in parenthesis) (mean ± SD and minimum – maximum in parenthesis) in muscle
of analysed fishes (mg.kg-1 w.w.); The values with identical
superscript in the column are not significant at the p<0.05 level.

differences in Hg accumulation among sites have been the Olsina and Spicak brooks, Czech Republic (Dvorak
recorded (p<0.05). et al. 2016). Oppossite, lower mean concentrations
Comparable results are presented by Stewart et al. are known from upper Morava River, Czech Republic
(2011) for brown trout muscle from the South Canter- (Valova et al. 2010) and upper Nitra River, Slovakia
bury rivers, New Zealand. Higher Hg concentrations in (Andreji et al. 2018).
fish muscle have been presented for brown trout from

382 Copyright © 2018 Neuroendocrinology Letters ISSN 0172–780X • www.nel.edu

 Ecological risk analysis of toxic metals concentrations in the Smeda river

Hg in relation to other metals as well as to age, (sites 9–10) were detected, similar to Hg. Significant
standard length and total weight shows a positive cor- differences have been confirmed in Co accumulation in
relations with statistically high significant differences trout muscle among monitored sites (p<0.05). Higher
(p<0.05), except Cd (Table 4). Co concentrations for brown trout muscle from the
Pb – levels in analysed muscle samples of brown trout Otra River, southern Norway were presented by Broth-
reached the values 0.01–0.29 mg.kg–1 w.w. (Table 3). The eridge et al.(1998). Authors Ylmaz et al. (2007) found
highest mean concentration at site 3 and lowest mean higher Co accumulation in tissues of chub (Leuciscus
concentration at site 1, were noted. In this case statisti- cephalus) from the Saricay river. On the other hand,
cally significant differences in Pb accumulation among Erdogrul et al. (2007), Karadede et al. (2004) and Karad-
sites have been recorded (p<0.05). Lower Pb concentra- ede et al. (2000) did not find Co in fish samples. Co is
tions (<0.06 mg.kg–1) are given from the upper Jihlava accumulated in some enzymes as vitamin B12 and 500
River (Valova et al. 2010) and South Canterbury rivers, mg/day is toxic to man (Bowen, 1979).
New Zealand (Stewart et al. 2011). Higher values of Pb In the case of Co accumulation in muscle a posi-
(0.36–0.54 mg.kg–1) in analysed muscle of brown trout tive correlation relationships were confirmed between
are known from the upper Nitra River (Stranai 1998). analysed metals, age, standard length and total weight
Comparable results to our findings have been presented (Table 4), but without statistical significances (p>0.05).
by Dvorak et al. (2016) in brown trout muscle from the
brooks of the military training area of Boletice, Czech Hygienic limits
Republic. The hygienic limits (Codex Alimentarius, Czech Repub-
A positive correlation relationships between Pb and lic) for mercury, lead, cadmium and cobalt are defined
other metals, age, standard length and total weight were as 0.5, 0.3, 0.05 and 0.05 mg.kg–1 w.w. , respectively. In
detected (Table 4). our study the contaminants (Hg, Pb, Cd and Co) did
Cd values fluctuated in relatively close range (0.01– not exceed hygienic limits. Codex Alimentarius was not
0.04 mg.kg–1 w.w.). The highest mean concentration exceeded at any single fish, however in lower sites of
was recorded at site 3 and lowest mean concentration the river stream were caught some fish with higher level
was detected at site 1 (Table 3). Statistically significant in mercury – max 0.496 mg.kg–1 (sites 1–3), lead max
differences for Cd accumulation in brown trout muscle 0.297 mg.kg–1 (sites 2–3).
were noted among analysed sites. Mean muscle concen-
trations at levels 0.04–0.10 mg.kg–1 have been presented CONCLUSIONS
from upper Nitra River, Slovakia (Stranai 1996; Andreji
et al. 2018). Lower Cd concentrations have been pub- Our research has presented data on the levels of toxic
lished for brown trout from the upper Jihlava River, metals in water, sediment, and fish muscles obtained
Czech republic (Valova et al. 2010) and South Canter- from brown trout – Salmo trutta morpha fario, from 10
bury rivers, New Zealand (Stewart et al. 2011), as well localities of the Smeda River. Toxic metals as pollutants
as for relative Salmo trutta macrostygma from Munzur play important role in human health, because they con-
Stream, Tunceli, Turkey (Can et al. 2012). On the other taminate environment and food chain. The potential
hand, comparable results to our have been published by ecological risk of toxic metal concentrations in the sedi-
Dvorak et al. (2016) from brooks of military training ments indicated that five sites in the middle and lower
area of Boletice (Czech Republic). reaches posed small to moderate ecological risk. Two
In the case of Cd a positive correlation relationships sites (2, 3) represent a potential higher ecological risk.
between all analysed indicators were found (Table 4), From our correlations, there is evidence of elevated
but without statistically significant differences (p>0.05). mercury values in larger trout (predation) and lower
Co muscle concentrations reached a very close values in young minor pollutants (bentophagus). We
range (0.00–0.03 mg.kg–1 w.w.), similar to Cd (Table 3). also observed an increase in Hg and Co from site 10
Higher mean concentrations at lower situated sites to site 2. In site 1, the level of the listed elements was
(mainly site 3) and lower concentrations at higher sites low, the site was under the natural reserve of Meandry
Smeda, and there is no regular sediment extraction and
excretion. The river between the sites 1 and 2 has the
Tab. 4. Correlations among analysed metals, age, standard length character of a low floodplain, and the water is flooded
and total weight. during the floods and thus does not transport the sedi-
Hg Pb Cd Co Age SL (mm) TW (g) ment as in the upper sites. That’s why metals do not get
so much into circulation. Pb and Cd is concentration-
Hg – 0.2534* 0.0072– 0.2960** 0.4941*** 0.5785*** 0.5092***
sensitive in lead shows slightly increased concentration
Pb – 0.2115* 0.1121– 0.0974– 0.0898– 0.0020– at sites No. 10, 8, 7, 4, 3, 2. Near this sites are located
Cd – 0.0654– 0.0767– 0.1408– 0.1116– textiles, glassworks and other metals processing manu-
Co – 0.1887– 0.1728– 0.1400–
factories with a long tradition. Our results confirmed
that the mean values of analysed fish did not exceed the
–p>0.05, *p<0.05, **p<0.01, ***p<0.001 limits valid in the Czech Republic.

Neuroendocrinology Letters Vol. 39 No.5 2018 • Article available online: www.nel.edu 383
 Petr Dvořák, Jaroslav Andreji, Ivana Faltová Leitmanová, Filip Petrách, Jan Mráz

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