Blood and urine cadmium and bioelements profile in nickel-cadmium battery workers in Serbia.

Although cadmium (Cd) is extensively used for nickel-cadmium battery production, few recent reports are available on the effect of this toxic metal on the imbalance of biometals in occupational exposure. The current study was carried out to determine the Cd level and its effect on the content of bioelements: zinc, cooper, magnesium, and iron in blood and urine of workers exposed to Cd during nickel-cadmium battery production. beta(2)-microglobulins (beta(2)-MG), as indicators of kidney damage, were determined in urine.The study group comprised 32 male nickel-cadmium battery workers, and the control group had 15 male construction workers with no history of Cd exposure. Levels of Cd and bioelements were determined in blood and urine by atomic absorption spectrophotometry.Cd concentration in blood of exposed workers was around 10 microg/L and in urine ranged from 1.93 to 8.76 microg/g creatinine (cr). Urine Cd concentration was significantly higher in exposed workers than in the controls, although no statistical difference in beta(2)-MG content was observed in urine between the two groups. Blood Zn and Mg level were significantly reduced and urine Zn level was increased in Cd-exposed group when compared with controls.The mean Cd concentrations in blood and urine did not exceed the recommended reference values of 10 microg/L in blood and 10 microg/g cr in urine. Cd exposure resulted in disturbances of Zn in blood and urine and Mg in blood but had no effect on Cu and Fe content in biological fluids.

Contribution to interaction between magnesium and toxic metals: the effect of prolonged cadmium intoxication on magnesium metabolism in rabbits.

The results obtained up to now indicate that increased intake of some heavy metals causes disorder of bioelements metabolism leading to their blood and organs decrease and higher elimination via the urine. As to lead and magnesium, our investigations indicated that the reaction is reversible and that increased intake of Mg eliminates Pb via urine. Some other findings suggest similar relations between Mg and certain heavy metals, thus pointing to significant role of Mg in toxicology of heavy metals and announcing a new chapter in the toxicology of metals entitled 'Mg in professional and ecotoxicology'. In this report we present the results of our investigations on the effect of Cd on Mg metabolism. The experiment was performed on rabbits given orally, every day, for 4 weeks 10 mg Cd/kg b.w. as aqueous solution of CdCl2. Magnesium content was determined in blood, urine, soft tissues and bones by the AAS method. Under the experimental conditions, Cd lead to statistically significant decrease of blood Mg (p < 0.001 after day 16) which was associated with increased Mg elimination via urine (p < 0.01). Statistically significant changes were not detected in the tissues, except in the liver where we found enhanced Mg content (p < 0.05), while its level in the muscles decreased (p < 0.01).

Compared effects of high oral Mg supplements and of EDTA chelating agent on chronic lead intoxication in rabbits.

Our previous experiments showed that excessive oral Mg intake has beneficial effects in chronic Pb poisoning, inducing decrease of Pb body burden and its increased elimination via urine. The aim of this work was to investigate and to compare the effect of Mg on urinary Pb elimination with the effect of calcium-disodium edetate (CaNa2EDTA)--chelating agent currently used in therapy of chronic Pb intoxication. Besides, under the same experimental conditions, biochemical parameters protoporphyrin IX (ppIX), zinc protoporphyrin (Znpp) and delta-aminolevulinic acid (ALA) were determined. Experiments were carried out on rabbits previously intoxicated for 4 weeks with 20 mg Pb/kg b.w. per day. After the period of intoxication, one group of animals was given per os, for 28 days, 40 mg Mg/kg, the other one was i.v. treated for 7 days with 15 mg CaNa2EDTA/kg (therapeutic doses), while the third one (rabbits without therapy) served as a control. During the period of detoxication, lead was determined in blood and urine samples, and ppIX and Znpp were determined in blood and ALA in urine. Results suggest that oral treatment with magnesium, although inducing later Pb elimination than EDTA, has even better effect on investigated biochemical parameters than chelating therapy.

Prophylactic effect of high magnesium intake in rabbits exposed to prolonged lead intoxication.

The ability of magnesium to prevent chronic lead intoxication was investigated by simultaneous oral treatment with lead and magnesium. Rabbits were intubated daily, for 28 d, with aqueous solutions of lead nitrate and magnesium acetate to give a lead dose level of 20 mg/kg and a magnesium dose level of 40 mg/kg body weight per day. A control group was treated only with lead. Supplementation with magnesium was found to be effective in reducing the lead content in blood and enhancing lead elimination via the urine. Results suggest that oral treatment with magnesium could possibly prevent deposition of lead in the body.

Simplified sample preparation for fluoride determination in biological material.

A simple and rapid preparation method for the determination of fluoride in biological materials (blood and food) of various origins, is described. A homogenized sample was placed in a plastic diffusion cell and calcium phosphate added, it was then dried at 55 degrees C and treated with 70% HClO4 and 40% AgClO4. After digestion for 24 h at 55 degrees C, the fluorides released were fixed on the upper part of a diffusion cell containing a thin layer of NaOH. The analyses of the diffused fluoride were carried out with an ion-selective electrode. The proposed microdiffusion method, without mineralization, enables quantitative separation of the fluoride from the biological samples.

The effect of dose on maternal-foetal transfer of fluoride in rabbits.

Placental transfer of fluoride was investigated by fluoride determination in the bones and teeth of newborn rabbits whose mothers had been treated with fluoride during pregnancy. The mothers were given doses of 0, 0.10, 0.52 and 1.05 mmol fluoride per kg body weight as sodium fluoride, from the 16th day after conception to the end of pregnancy. All the doses produced a significant increase of fluoride level in the bones and teeth of newborn rabbits, indicating that the placenta was no barrier for the passage of fluoride.

Direct determination of lead in blood by differential pulse stripping voltammetry.

A simple and rapid method for determination of lead in blood by differential pulse stripping voltammetry (DPS) without preliminary mineralization of the sample, is described. Lead determination was performed in native samples of blood in the electrolyte of Britton-Robinson buffer (pH 5-5.5). The proposed method is shown to be reproducible and in good agreement with the reference technique AAS used on mineralized blood samples. Our results indicate that differential pulse stripping voltammetry is a reliable, rapid and highly sensitive method for blood lead analysis.

Levels of lactate dehydrogenase and creatine kinase in plasma of fluoride-treated rabbits.

The effect of different concentrations of fluoride (as sodium fluoride) on the enzymes lactate dehydrogenase (LDH, EC 1.1.1.27) and creatine kinase (CK, EC 2.7.3.2) in rabbit plasma was investigated in vivo and in vitro. Rabbits were dosed orally, for 30 days, with fluoride at 2, 10 or 20 mg per kg body weight as sodium fluoride. LDH and CK levels were determined at 10-day intervals during the treatment. Fluoride, depending on the applied dose, inhibited, had no effect or stimulated the investigated enzymes in vivo. On the other hand, fluoride had no effect on the activity of LDH and CK in vitro.