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RESEARCH ARTICLE

Subacute co-exposure to low doses of ruthenium(III) changes the distribution, excretion and biological effects of silver ions in rats

Nicoleta Vedeanu A J , Cezara Voica B J , Dana Alina Magdas https://orcid.org/0000-0001-8101-9843 B , Bela Kiss C J , Maria-Georgia Stefan C , Ramona Simedrea D , Carmen Georgiu E J , Cristian Berce F , Oliviu Vostinaru https://orcid.org/0000-0003-4505-4005 G K , Rodica Boros E , Ionel Fizesan C , Marius Emil Rusu H , Adriana Grozav I , Felicia Loghin C and Daniela-Saveta Popa C
+ Author Affiliations
- Author Affiliations

A Department of Pharmaceutical Physics – Biophysics, Faculty of Pharmacy, Iuliu Haţieganu University of Medicine and Pharmacy, 8 Victor Babes, 400012 Cluj-Napoca, Romania.

B National Institute for Research and Development of Isotopic and Molecular Technologies, INCDTIM Cluj-Napoca, 67-103 Donath, 400293 Cluj-Napoca, Romania.

C Department of Toxicology, Faculty of Pharmacy, Iuliu Haţieganu University of Medicine and Pharmacy, 8 Victor Babes, 400012 Cluj-Napoca, Romania.

D Department of Physiology, Faculty of Medicine, Iuliu Haţieganu University of Medicine and Pharmacy, 8 Victor Babes, 400012 Cluj-Napoca, Romania.

E Department of Pathological Anatomy, Faculty of Medicine, Iuliu Haţieganu University of Medicine and Pharmacy, 8 Victor Babes, 400012 Cluj-Napoca, Romania.

F Practical Skills and Experimental Medicine Centre, Iuliu Haţieganu University of Medicine and Pharmacy, 8 Victor Babes, 400012 Cluj-Napoca, Romania.

G Department of Pharmacology, Physiology, Physiopathology, Faculty of Pharmacy, Iuliu Haţieganu University of Medicine and Pharmacy, 8 Victor Babes, 400012 Cluj-Napoca, Romania.

H Department of Pharmaceutical Technology and Biopharmacy, Faculty of Pharmacy, Iuliu Haţieganu University of Medicine and Pharmacy, 8 Victor Babes, 400012 Cluj-Napoca, Romania.

I Department of Organic Chemistry, Faculty of Pharmacy, Iuliu Haţieganu University of Medicine and Pharmacy, 8 Victor Babes, 400012 Cluj-Napoca, Romania.

J These authors contributed equally to this work.

K Corresponding author. Email: oliviu_vostinaru@yahoo.com

Environmental Chemistry 17(2) 163-172 https://doi.org/10.1071/EN19249
Submitted: 27 March 2019  Accepted: 25 October 2019   Published: 11 December 2019

Environmental context. Although ruthenium is a technology-critical element used in several new industries, little is known about its environmental impact or possible human health risks. We report a toxicological evaluation of laboratory animals during co-exposure to ruthenium and silver. We identified interactions between the two elements that could lead to unwanted biological effects.

Abstract. Ruthenium is one of the rarest metals on Earth that is classified as a technology-critical element (TCE). Silver, however, is well known for its antibacterial and immunostimulant properties. The increasing use of Ru and Ag in medicine and daily life makes simultaneous exposure possible, with unknown pharmacokinetic or toxicological consequences for the human organism. Thus, the present study investigated the influence of co-exposure to RuIII on the subacute toxicity of Ag ions in rats after repeated daily administration for 28 days of low doses by oral gavage. The subacute toxicity was investigated by the evaluation of several biochemical and hematological parameters, evaluation of specific oxidative stress biomarkers from liver and kidney, and histopathological investigation of liver and kidney tissue samples after 28 days of exposure in female rats. In addition, Ag and Ru concentrations were determined by inductively coupled plasma mass spectrometry (ICP-MS) in urine, liver and kidney parenchyma in male rats. The obtained results showed that co-exposure to low doses of RuIII and Ag did not produce any significant biochemical, hematological or histopathological alterations in the treated female rat groups, except for an increased red cell distribution width (RDW) value. A decrease of urinary excretion of Ag and of the Ag concentration in kidneys was observed in the male rat group co-exposed to RuIII and Ag. This is the first in vivo study investigating the toxic effect of co-exposure to low doses of Ag and Ru ions, and the obtained results may justify further research on this subject, mainly on the investigation of possible competitive mechanisms.

Additional keywords: hematology, ICP-MS, organ toxicity, TCEs, toxicokinetics.


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