JOURNAL OF ENVIRONMENTAL GEOGRAPHY Journal of Environmental Geography 9 (3–4), 1– DOI: ISSN: 2060 -467X WATER QUALITY SURVEY OF STREAMS FROM RETE ZAT… [610254]

JOURNAL OF ENVIRONMENTAL GEOGRAPHY
Journal of Environmental Geography 9 (3–4), 1–
DOI:
ISSN: 2060 -467X

WATER QUALITY SURVEY OF STREAMS FROM RETE ZAT MOUNTAINS (ROMAN IA)

Mihai -Cosmin Pascariu1,2, Tiberiu Tulucan3,4, Mircea Niculescu5, Iuliana Sebarchievici2,
Mariana Nela Ștefănuț2*

1Vasile Goldiș Western University of Arad, Faculty of Pharmacy, 86 Liviu Rebreanu, RO-310414 , Arad, 5 Romania
2National Institute of Research & Development for Electrochemistry and Condensed Matter – INCEMC 7 Timișoara, 144 Dr. Aurel
Păunescu -Podeanu , RO -300569, Timișoara, Romania
3Vasile Goldiș Western University of Arad, Izoi -Moneasa Center of Ecological Monitoring, 94 Revoluției 9 Blvd., RO -310025,
Arad, Romania
4Romanian Society of Geography, Arad subsidiary, 2B Vasile Conta, RO -310422, Arad, Roma nia
5University Politehnica Timișoara, Faculty of Industrial Chemistry and Environmental Engineering, 6 Vasile 12 Pârvan Blvd., RO –
300223, Timișoara, Romania
*Corresponding author, e-mail: [anonimizat]

Research article, received 3 July 2016, accepted 14 November 2016
Abstract
The Retezat Mountains, located in the Southern Carpathians, are one of the highest massifs in Romania and home of the Retezat
National Park, which possesses an important biological value. This study aimed at the investi gation of water quality in creeks of the
Southern Retezat (Piule -Iorgovanul Mountains) in order to provide information on pollutants of both natural and anthropogenic origin,
which could pose a threat for the human health. Heavy metal and other inorganic i on contents of samples were analyzed with on -site
and laboratory measurements to estimate water quality. The samples were investigated using microwave plasma – atomic emission
spectrometry to quantify specific elements, namely aluminium, cadmium, cobalt, c hromium, copper, iron, magnesium, manganese,
molybdenum, nickel, lead and zinc. The results were compared with the European Union and Romanian standards regarding drinkin g
water and surface water quality. The studied heavy metals have been found to be in v ery low concentrations or under the method’s
detection limit. Thus, in the microbasin corresponding to the sampling points, there seems to be no heavy metal pollution and , from
this point of view, the samples comply as drinking water according to the Europ ean Union and Romanian recommendations. Our
findings confirm that the Retezat Mountains are still among the least contaminated regions in Europe and that the ecosystem a nd the
human health is not negatively influenced by water quality problems.
Keywords: water chemical analysis, surface water quality, heavy metals, MP -AES, Retezat National Park
INTRODUCTION
Heavy metals are considered common pollutants of the
environment, having both natural and anthropogenic ori-
gins (Tchounwou et al. , 2012 ; Bradl et al. , 2005). The
rapid development of modern world has accelerated their
release into the biosphere (Mosa et al. , 2016 ; Panagos et
al., 2013). Some of the chemical species that contain
heavy metals can be highly toxic when inhaled or in-
gested. They can have an impact on almost every organ
and system in a living organism, posing a serious threat to
the stability of the ecosystems and a danger for the human
health (Jaishankar et al. , 2014 ; Bradl et al. , 2005). They
constitute the main contaminant category that aff ects Eu-
rope, contributing to around 30 -35% in soil and ground-
water contamination (Panagos et al. , 2013). Besides air
pollution, heavy metals have been regarded, in the last
decades, the greatest immediate health threat in Central
and Eastern Europe (Fitzge rald et al. , 1998). The influ-
ence of metal pollution on the river ecological status in Europe is evaluated according to the Water Framework
Directive (Roig et al., 2016).
The Retezat National Park is located in the western
part of the Southern Carpathian M ountain Range (Roma-
nia, Hunedoara County). It possesses a high biological
value and has thus been added to the UNESCO’s Man and
the Biosphere reserves network. The park includes 19
peaks above 2000 m elevation and it has been proposed as
a model for the co nservation efforts in Romania and other
countries (Bytnerowicz et al. , 2005). While several stud-
ies from the scientific mainstream literature have dealt
with the geology and hydrogeology of the area (Povară
and Ponta , 2010) or the composition of mountain lake sed-
iments (Catalan , 2015; Camarero et al. , 2009; Rose et al. ,
2009), studies regarding the composition of surface creeks
seem to be scarce or non -existent.
In this work, several springs and streams from the
Southe rn Retezat were analyzed for the presence of heavy
metals and other ions (cations and anions). The tested cat-
ions include ammonium (NH 4+), arsenic (As3+), calcium
(Ca2+), iron (Fe2+/Fe3+) and other heavy metals (e.g., lead

2 Pascariu et al. (2016 )

Pb2+), while the anions that were searched for include
halides (chloride Clˉ, bromide Brˉ, iodide Iˉ), nitrite
(NO 2ˉ) and sulfate (SO 42ˉ), all of them being determined
according to the chemical methods stipulated in the Ro-
manian Pharmacopoeia (1993) or by using test strips.
The results we re supplemented by microwave plasma –
atomic emission spectrometry (MP -AES) determina-
tions for some metals, i.e. aluminium, cadmium, cobalt,
chromium, copper, iron, magnesium , manganese, mo-
lybdenum, nickel, lead and zinc. Most of these species
are included in the category of heavy metals (Duffus ,
2002).
STUDY AREA
The studied area ( Fig. 1 ) belongs to the southern part
of the Retezat Mountains (Bytnerowicz et al. , 2005),
also known as Southern Retezat (Retezatul Sudic, in
Romanian) , and is located on the southern slope of the
Piule -Iorgovanu Mountains (Ardelean , 2010; Povară
and Ponta , 2010), between 1529 and 1871 m of altitude.
The stream water samples ( Fig. 1 ) were collected at six
sampling points at Scorota cu Apă and Scorota Seacă
(the headwaters of Scorota River) in the upper part of the Jiul de Vest River basin (Iordache et al. , 2015;
Ujvári , 1972). The microbasins corresponding to the
sampling points contain active streams with lengths
which vary between 100 and 500 m, and with a dis-
charge usually between 2 and 5 L/s. The sampling
points were allocated by considering these short
lengths and their relative position to the Scorota sheep-
fold: near the sheepfold, which is also the lowest part
of the grazing area, and in the higher li mit of this area,
with approximately 100 m of altitude between the dif-
ferent sample points.
From geological point of view, mostly sedimen-
tary rocks cover the surface, like quartz sandstones,
marl and marl -limestones, with patches of schists and
limestones. The most important soil types are humus –
iron-illuvial podzols, humus -silicate soils, brown pod-
zols and brown acidic soils. These mountains are char-
acterized by a rich flora and fauna. Subalpine meado ws
(grassland) predominate, being in contact with the up-
per limit of the coniferous domain, composed mainly
of Norway spruce ( Picea abies ). Carex and Festuca
meadows alternate with mountain pine, juniper shrubs
and dwarf shrubs composed of Vaccinium vitis -idaea
and Vaccinium myrtillus (Bytnerowicz et al. , 2005;

Fig. 1 Location of the sampling points

Water quality survey of streams from Retezat Mountains (R omania) 3

Kern and Popa , 2009; Mâciu et al. , 1982; Tulucan et al. ,
1999), as can be seen in Fig. 2 (left ). The climate is conti-
nental and typical for high mountain areas (Povară and
Ponta , 2010). Prior to sampling, weather was stable with
constant atmospheric pressure. There was no record of
rainfall or snowfall that could have produced signs of in-
direct contamination (e.g., acid rain or residual grazing
waste).
The list of analyzed samples, together with time,
location and on -site measured parameters, are given in
Table 1. Samples 1 -3 come from springs which origi-
nate in fluvial deposits from non -karst rocks (sand-
stones). For samples 2 and 3, the measurements wer e
taken near a confluence of two very short creeks, which
combine to form a right tributary of Scorota cu Apă
stream. Sample 4, corresponding to the highest meas-
ured point, comes from a spring localized in non -cal-
careous detrital rocks; the sampling was do ne in a ra-
vine with erosional slopes ( Fig. 2, right ). Samples 5 and
6 were collected near Scorota sheepfold from two
creeks that flow over Holocene detrital deposits. The
catchment is located in the Festuca meadows perime-
ter; sampling sites corresponding t o samples 1 -3, 5 and
6 are located in the juniper floor, where juniper clusters
alternate with Festuca meadows. Due to the fact that the sampling was performed at
the beginning of November, any organic pollution that
might have appeared because of grazing should have been
washed by precipitations in the two months that have
passed since the ending of the grazing period.
METHODS
Sampling and in situ measurements
Geographic coordinates and altitudes were established us-
ing a Magellan Meridian Platinum Mapping GPS re-
ceiver, while air temperature and pressure were recorded
with a portable Auriol weather station. Sample tempera-
ture, pH and electrical conductivity (EC) were registered
with a portable Hanna HI 98130 Combo pH&EC measur-
ing device. Nitrites and sulfate s were measured in situ using
Merck test strips (Merckoquant® Nitrit -Test and
Merckoquant® Sulfat -Test) (Table 1 ).
We have generally followed ISO 5667 -3 guidelines
for sampling. To prevent contaminations, thoroughly
cleaned plastic recipients were used (Bradl et al ., 2005;
Ogoyi et al. , 2011), prepared in the laboratory by pro-
tracted soaking with 2 M nitric acid followed by rinsing
with double distilled water. They were also conditioned in
situ with several aliquots of the water to be sampled. After
Fig. 2 Environment of the sampling sites (left side: juniper forest and Festuca meadows, characteristic for
samples 1, 2, 3, 5 and 6; right side: eroded mountain slopes in the case of sample 4)
Table 1 Sampling parameters
Parameter / Sample 1 2 3 4 5a 6a
Date (day/month/year) 01/11/2014 01/11/2014 01/11/2014 01/11/2014 02/11/2014 02/11/2014
Time (UTC+2 hours) 12:00 13:00 13:10 16:00 09:00 09:10
Geographic
coordinates 45°17’57’’N
22°53’23’’E 45°17’55’’N
22°52’57’’E 45°17’55’’N
22°52’57’’E 45°17’57’’N
22°52’30’’E 45°17’53’’N
22°53’33’’E 45°17’53’’N
22°53’35’’E
Altitude [ m] 1620 1759 1759 1871 1533 1529
Air pressure [ mbar ] 842.8 828.3 828.3 817.6 -b -b
Air temperature [ °C] 25 22 22 15 -b -b
Sample temperature [ °C] 4.8 5.4 5.9 4.9 5.0 4.0
pH [pH units ] 8.40 7.92 8.02 8.00 8.13 8.18
EC [μS/cm ] ~ 10 < 10 < 10 < 10 < 10 < 10
a geographic coordinates and altitude were established using Google Earth (2015) software;
b not measured.

4 Pascariu et al. (2016 )

completing this protocol a volume of 350 mL of water was
collected. To avoid the loss of elements by adsorption on
the walls of the storage recipients, the samples were sta-
bilized by acidification to pH ~ 1 by adding 20 mL of 10%
nitric acid (Pascariu et al. , 2013).
Laboratory analysis
All glassware needed for analysis was washed with 2
M nitric acid and thoroughly rinsed with double dis-
tilled water just prior of being used. Preliminary anal-
yses were performed on filtrated samples the day after
they were collected acc ording to the general procedures
stated by the Romanian Pharmacopoeia (1993). A
blank solution (350 mL double distilled water with 20
mL 10% nitric acid) was also prepared in an identical
plastic container and tested for comparison. The fol-
lowing aqueous r eagents were used: Nessler’s reagent
(potassium tetraiodomercurate (II), K 2HgI 4, and potas-
sium hydroxide, KOH) for ammonium, sodium hypo-
phosphite (NaH 2PO 2) in hydrochloric acid (HCl) for ar-
senic, ammonium oxalate ((NH 4)2C2O4) for calcium,
silver(I) nitrate (AgNO 3) for halides, potassium hexa-
cyanoferrate(II) (K 4[Fe(CN) 6]) for iron, sodium sulfide
(Na 2S) for heavy metals (e.g., lead) and barium chlo-
ride (BaCl 2) for sulfates. The chemical reactions that
use these reagents are stated to have the following de-
tection limits: 0.3 ppm for ammonium, 1 ppm for arse-
nic, 3.5 ppm for calcium, 0.5 ppm for chlorides, 0.5
ppm for iron, 0.5 ppm for lead and 3 ppm for sulfates
(Romanian Pharmacopoeia 1993).
For MP -AES, an Agilent 4100 with web -inte-
grated Agilent MP Expert software was used. The in-
strument was adjusted using as calibration standard the
provided Wavelength Calibration Concentrate for ICP –
OES & MP -AES (Al, As, Ba, Cd, Co, Cr, Cu, Mn, Mo,
Ni, Pb, Se, Sr, Zn 50 mg/L, K 500 mg/L) and also an
AAS standard solution for Ca, Fe and Mg. The follow-
ing wave lengths (in nm) were measured: Al 396.152,
Cd 228.802, Co 340.512, Cr 425.433, Cu 324.754, Fe
259.940, Mn 403.076, Mg 285.213, Mo 379.825, Ni
352.454, Pb 405.781, and Zn 213.857. In contrast to
atomic absorption spectrometry (AAS), which is based
upon the absorption of a characteristic radiation,
atomic emission spectrometry (AES) uses the emission
of a characteristic wavelength for the determination of the analyte element. Plasma emission spectrometry uti-
lizes a plasma as the excitation source for atomic e mis-
sions, which, in MP -AES, is formed via the use of a
microwave field source. AES belongs to the most use-
ful and commonly used techniques for the analysis of
heavy metals, providing rapid and sensitive results in a
variety of sample matrices, although the detection lim-
its are higher than those of AAS (Bradl et al. , 2005;
Higson , 2006).
RESULTS AND DISCUSSION
The average water temperature was 5.0 °C, the mean pH
value was 8.11, while the measured EC value was around
or below 10 μS/cm for all samples ( Table 1). The in situ
tests using test strips did not indicate the presence of ni-
trites or sulfates (nitrite ion concentration less than 1
mg/L, sulfate ion concentration less than 200 mg/L, ac-
cording to test strips instructions). Also, the very low
measured EC indicates that the total dissolved solids
(TDS) must be under 10 ppm (Lenntech , 2016).
The samples were tested for the presence of ammo-
nium, arsenic, calcium, halides (chloride, bromide, and io-
dide), iron, heavy metals (e.g., lead) and sulfates. Except
for a very faint opalescence obtained when sample 1 was
tested for calcium, all these tests were negative, an obser-
vation that supports the very low measured EC for all
samples ( Table 1 ).
MP-AES results are summarized in Table 2, while
the drinking water standards from EU (1998) and Roma-
nian “Law no. 311 from June 28, 2004” (Romanian Gov-
ernment 2004) are given in Table 3 for comparison with
the analyzed samples. As can be seen, except for a some-
what increased iron content in sample 1 (probably due to
the h umus -iron-illuvial podzols, which are present in the
area), the stud ied streams are within the limits specified
for drinking water (Brad et al. , 2015) by all specified
standards. The metal contents are generally low and there
is no observable trend downstr eam on any of the elements .
The Romanian environmental legislation regarding
surface water quality, stipulated in “Order no. 161 from
February 16, 2006” (Romanian Government 2006), is
summarized for the considered ions in Table 4. This sur-
face water qualit y classification is useful in order to es-
tablish the ecological status of all marine and continental
Table 2 MP-AES cation content results, in mg/L
Sample Concentration
Al Cd Co Cr Cu Fe Mg Mn Mo Ni Pb Zn
1 * * 0.03 * * 1.61 0.53 * 0.03 * 0.01 *
2 * * 0.03 * * 0.05 1.10 * 0.02 * 0.01 *
3 * * 0.02 * * 0.13 1.84 * 0.02 * * *
4 0.01 * 0.02 * * 0.08 0.18 * 0.02 * * *
5 0.01 * 0.02 * * 0.14 0.88 * 0.02 * * *
6 * * 0.02 * * 0.05 0.54 * 0.02 * * *
* under detection limit (< 0.005 mg/L).

Water quality survey of streams from Retezat Mountains (R omania) 5

Table 3 Drinking water standards comparative table; all values
are in units of mg/L unless stated otherwise (European Union ,
1998; Romanian Government , 2004)
Parameter EU
standards
1998 Romanian
law
no. 311/2004
pH [pH units] 6.5-9.5 6.5-9.5
EC [mS/cm] 2.500 2.500
TDS # #
Temperature [°C] # #
Aluminium (Al3+) 0.200 0.200
Ammonia/ammonium
(NH 3+NH 4+) 0.50 0.50
Cadmium (Cd2+) 0.0050 0.0050
Calcium (Ca2+) # #
Chromium (Cr3++Cr6+) 0.050 0.050
Cobalt (Co2++Co3+) # #
Copper (Cu2+) 2.0 0.1*
Iron (Fe2++Fe3+) 0.200 0.200
Lead (Pb2+) 0.010 0.010
Manganese (Mnx+) 0.050 0.050
Magnesium (Mg2+) # #
Molybdenum (Mox+) # #
Nickel (Ni2+) 0.020 0.020
Zinc (Zn2+) # 5.000
Chloride (Clˉ) 250 250
Nitrite (NO 2ˉ) 0.50 0.50
Sulfate (SO 42ˉ) 250 250
# not mentioned;
* is allowed as 2.0 mg/L if the distribution piping material con-
tains copper.
Table 4 Surface water quality classes depending on cation con-
tent, as stated in Romanian “Order no. 161 from February 16,
2006”; units are in mg/L, unless stated otherwise
Parameter Order no. 161 (2006)
I II III IV V
pH [pH units] 6.5 – 8.5
EC [mS/cm] No guideline
TDS Not mentioned
Temperature [°C] No guideline
Aluminium (Al3+) Not mentioned
Cadmium (Cdx+) 0.0005 0.001 0.002 0.005 >0.005
Chromium, total
(Cr3++Cr6+) 0.025 0.050 0.100 0.250 >0.250
Calcium (Ca2+) 50 100 200 300 >300
Cobalt (Co3+) 0.010 0.020 0.050 0.100 >0.100
Copper (Cu2+) 0.020 0.030 0.050 0.100 >0.100
Iron, total
(Fe2++Fe3+) 0.3 0.5 1.0 2 >2
Lead (Pbx+) 0.005 0.010 0.025 0.050 >0.050
Magnesium (Mg2+) 12 50 100 200 >200
Manganese, total
(Mn2++Mn7+) 0.05 0.1 0.3 1 >1
Nickel (Nix+) 0.010 0.025 0.050 0.100 >0.100
Zinc (Zn2+) 0.100 0.200 0.500 1.000 >1.000
Chloride (Clˉ) 25 50 250 300 >300
Sulfate (SO 42ˉ) 60 120 250 300 >300 aquatic ecosystems, including rivers and lakes, both natu-
ral and artificial. The evaluation of the considered quality
elements, like chemical and physical -chemical parame-
ters, can indicate the presence of certain natural environ-
ments, minor alterations of these o r the degree of an-
thropic impact, and, respectively, the status of water bod-
ies quality in a certain amount of time. There are five eco-
logical states being defined for natural rivers and lakes:
very good (I), good (II), moderate (III), poor (IV) and bad
(V). According to Table 4, the streams corresponding to
samples 3 -6 belong to class I. An exception could be the
stream that provided sample 1, which belongs to class IV
according to the iron content. Also, according to the lead
content, the streams that provided samples 1 and 2 could
belong to class II or III, but these low measured lead levels
may more realistically be accounted for by the MP -AES
precision limit.
Our findings support the previous studies which
state that the Retezat Mountains are among t he least con-
taminated regions in Europe (Catalan , 2015 ; Catalan et
al., 2009). Regarding the studied parameters and consid-
ering the low levels of dissolved ions, water quality was
found to be good or very good. Thus, heavy metals do not
pose any ecological or human risk in the studied area.
CONCLUSIONS
MP-AES, alongside some classical analytical procedures,
were used to analyze the water quality of springs and
creeks from the Retezat National Park. For all tested sam-
ples, heavy metals were at very low level s or under the
detection limit for the chemical reactions employed and
the MP -AES method applied. From this point of view, the
samples comply as drinking water according to the EU
and Romanian recommendations. The average water tem-
perature was 5.0 °C, the mean pH value was 8.11, while
the measured EC value was around or below 10 μS/cm for
all samples, the later also confirming the very small ion
content present in the analyzed mountain streams. In the
microbasin corresponding to the sampling points, there
seems to be no heavy metal pollution. Also, no other po-
tential sources of chemical pollution was recorded in the
studied perimeter during our survey.
Acknowledgements
Part of this paper was presented at The 17th DKMT Euro-
regional Conference on Environment and Health, June 5 –
6, 2015, Szeged, Hungary. Some of the research was done
at the Center of Genomic Medicine of the “Victor Babeș”
University of Medicine and Pharmacy of Timișoara,
POSCCE 185/48749, contract 677/09.04.2015.
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