Electrochemical analysis of lead toxicosis in vultures

journal article in Web of Science

English

Lead as one part of heavy metals group pose a detrimental risk to human health and the environment due to its toxicity, even exposure to minuscule quantities can be life threatening. Levels of lead are not stable in the environment and vary according to industrial production, urbanization, climate changes and many other factors. It is not surprising that rapid, sensitive and simple analytical determination of metal ions in environment is very important. Electrochemical techniques are one of the best methods for detecting metals due to their low cost, high sensitivity and portability. The aim of this study was to compare various microwave digestion procedures for lead(II) ions isolation in vultures samples of vultures available in very small quantities (5-20 mg) followed by differential pulse voltammetry as a detection method. We found that the combination of (65%, w/w) HNO3 + (30%, w/w) H2O2 is advantageous for the resulting electrochemical response. To determine the effect of mineralization on the height of the lead(II) ions peak, eight different mineralization programs were tested. It clearly follows from the results obtained that 200 W power for 30 min. is the most optimal for mineralisation of vultures' samples. In the following part of the study, the influence of four different locations of samples in the rotor of used microwave system was investigated. Under the optimized conditions, samples of blood and eggs from vultures poisoned by lead(II) ions were prepared and electrochemically analysed. Three types of working electrodes as hanging mercury drop electrode, carbon paste electrode and screen printed electrode made of multi-walled nanotubes (MWNTs) were employed for this purpose. All three electrodes were sensitive enough to be used for analysis of real samples. Based on the results obtained it clearly follows that the level of lead(II) ions in intoxicated vultures ranged from 1 to 5 ug/ml of blood. In addition, it was found that the lead toxicosis was diagnosed in all vultures properly. Besides lead, cadmium was determined electrochemically and Ca, Mg, Fe, Zn and Cu spectrometrically. Besides the content of lead(II) and cadmium(II) ions, we determined metallothionein as a protein connected with protection of vertebrates against metal ions using differential pulse Brdicka reaction. The level of MT was determined as 1.82 +- 0.31 ug/mg of proteins in the intoxicated vultures compared with the control group 0.71 +- 0.19 ug/mg of proteins, which means more than a 250% increase of MT levels.

automated electrochemical detection, bioremediation, differential pulse voltammetry, heavy metal, diagnosis of toxicosis, metallothionein, spectrophotometry

HYNEK, D.; PRÁŠEK, J.; ADAM, V.; KREJČOVÁ, L.; TRNKOVÁ, L.; SOCHOR, J.; POHANKA, M.; HUBÁLEK, J.; BEKLOVÁ, M.; VRBA, R.; KIZEK, R.

2011

1. 12. 2011

ELECTROCHEMICAL SCIENCE GROUP, A SPOMENICE 7/12 , 19210 BOR, BELGRADE, VJ 12, SERBIA

Srbsko

1452-3981

INTERNATIONAL JOURNAL OF ELECTROCHEMICAL SCIENCE

6

12

Republic of Serbia

5980

6010

31