Pollution with trace elements and rare-earth metals in the lower course of Syr Darya River and Small Aral Sea, Kazakhstan

Piotr Rzymski; Piotr Klimaszyk; Przemysław Niedzielski; Włodzimierz Marszelewski; Dariusz Borowiak; Kamil Nowiński; Ainur Baikenzheyeva; Rakhat Kurmanbayev; Nikolai Aladin

doi:10.1016/j.chemosphere.2019.06.036

Pollution with trace elements and rare-earth metals in the lower course of Syr Darya River and Small Aral Sea, Kazakhstan

Chemosphere. 2019 Nov:234:81-88. doi: 10.1016/j.chemosphere.2019.06.036. Epub 2019 Jun 7.

Authors

Piotr Rzymski¹, Piotr Klimaszyk², Przemysław Niedzielski³, Włodzimierz Marszelewski⁴, Dariusz Borowiak⁵, Kamil Nowiński⁶, Ainur Baikenzheyeva⁷, Rakhat Kurmanbayev⁷, Nikolai Aladin⁸

Affiliations

¹ Department of Environmental Medicine, Poznan University of Medical Sciences, Poznań, Poland. Electronic address: rzymskipiotr@ump.edu.pl.
² Department of Water Protection, Faculty of Biology, Adam Mickiewicz University, Poznań, Poland.
³ Department of Analytical Chemistry, Faculty of Chemistry, Adam Mickiewicz University, Poznań, Poland.
⁴ Department of Hydrology and Water Management, Nicolaus Copernicus University, Toruń, Poland.
⁵ Department of Limnology, University of Gdańsk, Gdańsk, Poland; Limnological Station in Borucino, University of Gdańsk, Borucino, Poland.
⁶ Department of Limnology, University of Gdańsk, Gdańsk, Poland.
⁷ Kyzylorda State University, Kyzylorda, Kazakhstan.
⁸ Zoological Institute of Russian Academy of Sciences, Saint-Petersburg, Russia.

PMID: 31203044
DOI: 10.1016/j.chemosphere.2019.06.036

Abstract

Over recent decades the Aral Sea has faced a major human-driven regression leading to environmental, economic and health impacts. Previous research has indicated that its region may be highly polluted yet there is little recent data to assess the scale or nature of the pollution. The present study investigated the concentration of elements for which the World Health Organization (WHO) has established guideline levels (Al, As, B, Ba, Cd, Cr, Cu, Ni, Pb, Sb) as well as 16 rare-earth elements (Ce, Eu, Er, Gd, La, Nd, Pr, Sc, Sm, Dy, Ho, Lu, Tb, Tm, Y, Yb) in the Small Aral Sea (SAS) and its inflow, the Syr Darya River (SDR). The latter displayed increased levels of Al (mean 851 μg L^-1), As (35.8 μg L^-1), Cd (2.8 μg L^-1), Pb (10.1 μg L^-1) and U (4.9 μg L^-1), exceeding the guideline limits at selected sites. In the SAS these limits were exceeded at certain locations in the case of As and U. The total mean concentration of REEs in the SDR and SAS amounted to 22.6 and 61.7 μg L^-1, respectively, with Pr, Ce and Nd constituting the greatest share. The concentrations of B, Ba Cr, Cu, Se and Ni were below the WHO guideline levels at all studied sites while Sb and Hg were always below detection limits. This research provides an updated status on the levels of contamination of the surface waters in the ecological disaster zone of the Aral Sea in Kazakhstan.

Keywords: Aral Sea; Arsenic; Kazakhstan; Rare-earth elements; Syr Darya; Toxic metals.

MeSH terms

Environmental Pollution / analysis*
Humans
Kazakhstan
Metals, Rare Earth / analysis*
Metals, Rare Earth / toxicity
Oceans and Seas
Rivers / chemistry*
Trace Elements / analysis*
Trace Elements / toxicity

Substances

Metals, Rare Earth
Trace Elements