Heavy metals and metalloid content in vegetables and soil collected from the gardens of Zagreb, Croatia.

Aim of this study was to determine concentration of Pb, Cd, As and Hg in green leafy vegetables and soil in the urban area of Zagreb, Croatia and to determine if there is a connection between the contamination of soil and vegetables. Green leafy vegetables and soil samples were taken from the gardens located in the outskirts of the city. Concentrations of Pb, Cd, As and Hg were determined by atomic absorption spectrometry; showing that average concentrations of metals and metalloids in vegetables and in soil, regardless of the location of sampling were below the maximum allowed concentration (MAC). The analysis determined that metal concentrations in only nine vegetable samples (9%) were above maximum allowed values prescribed by national and European legislation (three with higher concentrations of Pb, one with a higher concentration of Cd and five with higher concentrations of Hg). Concentrations of contaminants present in the analysed samples, in general, are lower than the ones published in similar studies. The final distribution and concentration of contaminants in vegetables of Zagreb, besides industry and traffic, is affected by the dominant wind direction.

Effects of magnesium, chromium, iron and zinc from food supplements on selected aquatic organisms.

The aim of this study was to determine the effect of uncontrolled environmental disposal of food supplements containing magnesium (Mg), chromium (Cr), iron (Fe) and zinc (Zn) on selected aquatic organisms including freshwater algae Scenedesmus subspicatus and Raphidocelis subcapitata, water flea Daphnia magna and duckweed Lemna minor. Thirty different food supplements containing Mg, Cr, Fe and Zn were analyzed. Results were expressed as effective concentration 50 (EC50), i.e. growth inhibiting Mg, Cr, Fe and Zn (mg/L) concentration immobilizing 50% of treated organisms. Particular metal EC50 differed significantly (p < 0.001) among study organisms, as follows (in ascending order): Scenedesmus subspicatus EC50 Fe (median 46.9 mg/L) < Zn (59.8 mg/L) < Mg (73.0 mg/L) < Cr (88.1 mg/L) (KW-H(3;120) = 36.856; p < 0.001); Raphidocelis subcapitata EC50 Fe (median 44.9 mg/L) < Zn (52.6 mg/L) < Mg (62.2 mg/L) < Cr (76.8 mg/L) (KW-H(3;120) = 44.0936; p < 0.001); Daphnia magna EC50 Zn (median 59.4 mg/L) < Cr (79.2 mg/L) < Fe (80.8 mg/L) Mg (82.0 mg/L) (KW-H(3;120) = 39.2637; p < 0.001); and Lemna minor EC50 Zn (median 131.0 mg/L) < Fe (186.8 mg/L) < Mg (192.5 mg/L) < Cr (240.4 mg/L) (KW-H(3;120) = 58.6567; p < 0.001). Uncontrolled environmental disposal of food supplements containing Mg, Cr, Fe and Zn exerts adverse effects on aquatic organisms. Therefore, legal provisions should regulate both the utilization and disposal of food supplements into the environment.

Influence of Dietary Supplementation of Propolis and Bee Pollen on Liver Pathology in Broiler Chickens.

One of the major problems in intensive breeding of chickens is liver damage. The objective of this study was to determine the influence of dietary supplementation with propolis and bee pollen on liver pathology in broiler chickens. The study was conducted on 200 Ross 308 chickens equally distributed by sex that were divided into five groups. Throughout the whole study, the control group of chickens was fed with a basal diet, while the experimental groups of chickens were fed with the same diet further supplemented with propolis and bee pollen, each supplement given separately or in combination in a certain proportion. The study showed that the clusters of lymphocytes in the hepatocytes, the vacuolar degeneration and necrosis of the liver parenchyma, the bile ductule hyperplasia, and the various forms of pathological changes in the liver arteries and veins were more frequent in liver tissue samples of the control group compared to liver tissue samples of all the experimental groups (p < 0.001). The study further showed that all the previously mentioned histopathological lesions of liver tissue were always more extensive in the liver tissue samples of the control group than in the liver tissue samples of all the experimental groups (p < 0.001). The supplementation of broiler chickens with propolis and/or bee pollen has a strong protective effect on liver pathology in broiler chickens.