As part of my bachelor's degree, we determined the content of heavy metals in the
surface water of Drtijščica stream in order to assess their impact on human health. In
the water we determined arsenic (As), cadmium (Cd), cobalt (Co), chromium (Cr),
baking (Cu), molybdenum (Mo), nickel (Ni), lead (Pb), selenium (Se) and zinc (Zn).
The submitted work, i.e. sampling, was carried out in the February 2020 when six
samples were taken at six different sampling points. The samples were then filtered
and diluted with 1% nitric acid. For the determination of metals in water, we used the
accredited method of inductively coupled plasma - optical emission spectrometry (ICP-
OES), which enabled us to determine several metals in one sample simultaneously. A
multi-standard solution from Merck (VI) KGaA was used to prepare the standard
solutions. The results of our study were then compared with the maximum permitted
and recommended concentrations from domestic and foreign legislation and other
credible studies.
The results showed an increased concentration of Se and Co, as the value of the two
metals in all six samples exceeded the limits set by Slovenian legislation. The
concentrations of Pb, As, Cd and Cu also exceeded the limit values at most of the
sampling points. The measured values of Zn and Cr did not exceed the limit values in
any sample. The values of Mn, Mo and Ni were mainly below the detection limit, which
means that the concentration of these metals was too low for detection with the ICP-
OES device. Elevated concentrations of almost half of the investigated heavy metals,
indicate a poor ecological status, which can definitely have an effect on human health
and aquatic organisms.
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