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Open access

Milka Bogdanović and Petar Bulat

Biliary Function in Workers Occupationally Exposed to Aluminium Dust and Fumes

This study investigated billiary secretory function in workers occupationally exposed to aluminium dust and fumes. It included a group of 34 male workers aged (44.1±7.8) years and exposed up to 4.6 mg m-3 of aluminium dust and fumes in workplace air for (21.6±2.5) years, and a group of 30 unexposed control male workers. Serum and urine aluminium levels were measured in both groups before and after chelating treatment with 1 g deferoxamine by intramuscular injection. Billiary function was assessed by measuring gamma-glutamyl transpeptidase, alkaline phosphatase, 5-nucleotidase, cholesterol and its fractions, total and indirect bilirubin, and bile acids. We then analysed the relationship between Al exposure and billiary function.

In the exposed group mean serum aluminium was significantly higher [(4.91±3.86) μg L-1] than in controls. The same was true for urine Al before [(1.57±1.93) μg L-1] and after deferoxamine [(11.51±14.97) μg L-1]. Total and indirect bilirubin and alkaline phosphatase were significantly higher in the exposed than in control workers, and they correlated with urine Al after the chelating treatment.

Our findings suggest that chronic occupational exposure to aluminium dust and fumes leads to a significant body retention of aluminium. The impaired biliary secretion in the exposed workers manifested itself in subclinical signs of cholestasis.

Open access

Milka Bogdanović, Ana Janeva and Petar Bulat

Histopathological Changes in Rat Liver After A Single High Dose of Aluminium

Aluminium (Al) exposure may affect the liver of experimental animals. This investigation aimed at evaluating morphological changes in rat liver after a single high dose of Al (as metallic powder suspension). A total of forty female Wistar rats were divided in one exposed and one control group, 20 rats each. The exposed rats received 0.5 mL of sterile physiological suspension of fine Al powder in the concentration of 100 mg mL-1 intraperitoneally (50 mg Al per rat). After 7 weeks all animals were killed (by exsanguination from the abdominal aorta in ether anaesthesia). Liver aluminium was analysed using electrothermal atomic absorption spectrometry. For light microscopy the liver tissue was stained with hematoxylin and eosin, and for histochemical analysis with aurin threecarbocsillic acid (aluminon).

Liver Al level was markedly higher in the exposed (37.1 μg g-1) than in control rats (0.71 μg g-1). The exposed rats showed crystalloid Al inclusions in the capsular, subcapsular, and portal liver tissue. The basic liver structure remained intact. Slightly multiplied bile ductuli were found in 16 of 20 exposed and in 8 of 20 control rats. Three exposed rats had mycrovesicular steatosis. The peritoneum and Glisson's capsule showed strong macrophage infiltration and a foreign-body-like reaction with multiple giant macrophages containing Al crystalloid inclusions. Although this reaction was a defense against the metal, some Al passed this barrier and entered the liver tissue, exerting toxic effects in bile ductuli and hepatocytes.

Open access

Petar Bulat, Biljana Potkonjak and Ivana Đujić

Lipid Peroxidation and Antioxidative Enzyme Activity in Erythrocytes of Workers Occupationally Exposed to Aluminium

Current research indicates that lipid peroxidation could have a role in aluminium toxicity. The aim of this study was to asses lipid peroxidation and antioxidative enzyme activity in erythrocytes of workers occupationally exposed to aluminium. We investigated a group of 59 workers (Al group) exposed to aluminium fumes (contamination factor F=8.07 to 13.47, national maximal allowed concentration value is 2 mg m-3). The control group (C group) consisted of 75 subjects employed in lime production who had not been occupationally exposed to aluminium or any known toxic substance.

Erythrocyte aluminium concentrations were significantly higher in the exposed group than controls [Al group (8.41±3.66) μg L-1, C group (5.60±0.86) μg L-1, p<0.001]. In the Al group, erythrocyte malondialdehyde concentration was also significantly higher [Al group (189.59±81.27) μmol L-1, C group (105.21±49.62) μmol L-1, p<0.001] and antioxidative enzyme activity reduced for glucoso-6-phosphate-dehydrogenase [Al group (5.05±1.70) IU g-1 Hb, C group (12.53±4.12) IU g-1 Hb, p<0.001], glutathione reductase [Al group (1.41±0.56) IU g-1 Hb, C group (1.89±0.57) IU g-1 Hb, p<0.001], glutathione peroxidase [Al group (12.37±5.76) IU g-1 Hb, C group (15.54±4.85) IU g-1 Hb, p<0.001], catalase [Al group (116.76±26.60) IU g-1 Hb, C group (158.81±71.85) IU g-1 Hb, p<0.001] and superoxide dismutase [Al group (1175.8±149.9) IU mg-1 Hb, C group (1377.9±207.5) IU mg-1 Hb, p<0.001].

Open access

Martin Popević, Gordana Kisić, Milenko Đukić and Petar Bulat

Work Ability Assessment in a Patient with Wilson's Disease

Wilson's disease (WD) is a rare, progressive autosomal recessive disorder characterised by impaired transport and excessive accumulation of copper in the liver, brain, and other tissues. The disease is diagnosed based on clinical manifestations and screening tests results. Work ability assessment of patients with WD is based on the analysis of liver, kidney, neurological, and cognitive impairments, and takes into account patient's level of education.

This article presents a case with a 48-year-old male patient, who was admitted for work ability assessment due to polymorphic symptoms. The patient had been working as a salesman for 28 years. A detailed interview and examination by occupational health and other medical specialists revealed that the patient had been suffering from Wilson's disease from the age of 13, and had now developed hepatic manifestations (compensated liver cirrhosis with portal hypertension), neurological manifestations (dystonia, dysarthria, muscle weakness, vertigo), and psychiatric manifestations (depression, insomnia, cognitive impairment) of the disease, including problems partially caused by long-lasting treatment with copper chelating agents (neurological and haematological manifestations). There were no ocular manifestations of Wilson's disease (Kayser-Fleischer rings or sunflower cataract).

The patient was assessed as having drastically diminished general work ability, dominantly due to neurological and psychiatric impairments caused by Wilson's disease.

Open access

Zorica Bulat, Danijela Đukić-Ćosić, Biljana Antonijević, Aleksandra Buha, Petar Bulat, Zoran Pavlović and Vesna Matović


The study was designed to investigate the influence of zinc (Zn) supplementation on cadmium-induced alterations in zinc, copper (Cu), and magnesium (Mg) status in rabbits. For this purpose, the concentrations of cadmium (Cd), Zn, Cu, and Mg were estimated in the blood, liver, kidney, and bone. The rabbits were divided in a control group, a Cd group-animals intoxicated orally with Cd (10 mg kg-1 bw, as aqueous solution of Cd-chloride), and a Cd+Zn group-animals intoxicated with the same dose of Cd and co-treated with Zn (20 mg kg-1 bw, as aqueous solution of Zn-sulphate). Solutions were administered orally, every day for 28 days. Sample mineralisation was performed with concentrated nitric acid (HNO3) and perchloric acid (HClO4) (4:1) and metal concentrations were determined by atomic absorption spectrophotometry (AAS). Zinc supplementation improved some of Cd-induced disturbances in bioelement levels in the investigated tissues. Beneficial effects of Zn on Zn and Cu levels were observed in blood, as well as on the Cu kidney level. The calculated values for Cu/Zn, Mg/Zn, and Mg/Cu ratios in blood suggest that Zn co-treatment reduces Cd-induced changes in bioelement ratios in blood.

Open access

Bojana Mandić, Stefan Mandić-Rajčević, Ljiljana Marković-Denić and Petar Bulat


The risk of occupational bloodborne infections (HBV, HCV, and HIV) among healthcare workers remains a serious issue in developing countries. The aim of this study was to estimate occupational exposure to bloodborne infections among general hospital workers in Serbia. This cross-sectional study was conducted in the spring of 2013 and included 5,247 healthcare workers from 17 general hospitals. The questionnaire was anonymous, self-completed, and included sociodemographic information with details of blood and bodily fluid exposure over the career and in the previous year (2012). Significant predictors of sharps injuries were determined with multiple logistic regressions. The distribution of accidents in 2012 was equal between the genders (39 %), but in entire career it was more prevalent in women (67 %). The most vulnerable group were nurses. Most medical doctors, nurses, and laboratory technicians reported stabs or skin contact with patients’ blood/other bodily fluid/tissue as their last accident. Healthcare workers from the north/west part of the country reported a significantly lower number of accidents over the entire career than the rest of the country (p<0.001). The south of Serbia stood out as the most accident-prone in 2012 (p=0.042).

Open access

Martin B. Popević, Srđan M. Janković, Srđan S. Borjanović, Slavica R. Jovičić, Lazar R. Tenjović, Aleksandar P.S. Milovanović and Petar Bulat


A frequently encountered exposure profile for hand-arm vibration in contemporary occupational setting comprises workers with a long history of intermittent exposure but without detectable signs of hand-arm vibration syndrome (HAVS). Yet, most of the published studies deal with developed HAVS cases, rarely discussing the biological processes that may be involved in degradation of manual dexterity and grip strength when it can be most beneficial - during the asymptomatic stage. In the present paper, a group of 31 male asymptomatic vibration-exposed workers (according to the Stockholm Workshop Scale) were compared against 30 male controls. They were tested using dynamometry and dexterimetry (modelling coarse and fine manual performance respectively) and cold provocation was done to detect possible differences in manual performance drop on these tests. The results showed reduced manual dexterity but no significant degradation in hand grip strength in the exposed subjects. This suggests that intermittent exposure profile and small cumulative vibration dose could only lead to a measurable deficit in manual dexterity but not hand grip strength even at non-negligible A(8) levels and long term exposures.