The Effect of Cadmium Ions and Cadmium Nanoparticles on Chicken Embryos and Evaluation of Organ Accumulation

Abstract

The presence of metals in the organism has both positive and negative influence on the functions of the body, depending on the concentration. Cadmium is one of the metals that have irrefutable negative effect. It is highly toxic metal with long biological half-life causing damage of kidneys, bones and has carcinogenic effect. The aim of this work was the study of the effect and distribution of the cadmium in the body and its comparison with cadmium nanoparticles – CdTe quantum dots (QDs). Model organism for these experiments was chicken embryo in 16th developmental day. The distribution of cadmium was analyzed after the application of 500 uL of cadmium solution (Cd ions) in concentration 1 mg/mL or 4.5 mg/mL). This solution was applied through the small hole in the egg shell onto the chorioallantoic membrane. After 24 hours of the incubation (37.5 C, 45% rH) liver, kidney, brain and hearth were extracted. The concentration of cadmium was analyzed after the mineralization of the samples by atomic absorption spectrometry and differential pulse voltammetry. The toxicity of cadmium solution was significantly higher compared to the solution of QDs. Embryos exposed to the cadmium ions exhibited 100% mortality after 24 hours. On the contrary, the mortality of embryos exposed to QDs was 0%. The highest levels of cadmium were detected in the kidneys (125 ug per g) and in the liver (107 ug per g).

The presence of metals in the organism has both positive and negative influence on the functions of the body, depending on the concentration. Cadmium is one of the metals that have irrefutable negative effect. It is highly toxic metal with long biological half-life causing damage of kidneys, bones and has carcinogenic effect. The aim of this work was the study of the effect and distribution of the cadmium in the body and its comparison with cadmium nanoparticles – CdTe quantum dots (QDs). Model organism for these experiments was chicken embryo in 16th developmental day. The distribution of cadmium was analyzed after the application of 500 uL of cadmium solution (Cd ions) in concentration 1 mg/mL or 4.5 mg/mL). This solution was applied through the small hole in the egg shell onto the chorioallantoic membrane. After 24 hours of the incubation (37.5 C, 45% rH) liver, kidney, brain and hearth were extracted. The concentration of cadmium was analyzed after the mineralization of the samples by atomic absorption spectrometry and differential pulse voltammetry. The toxicity of cadmium solution was significantly higher compared to the solution of QDs. Embryos exposed to the cadmium ions exhibited 100% mortality after 24 hours. On the contrary, the mortality of embryos exposed to QDs was 0%. The highest levels of cadmium were detected in the kidneys (125 ug per g) and in the liver (107 ug per g).