Jasna Huremović

Pulverized Banana Peel as an Economical Sorbent for the Preconcentration of Metals

A procedure for the determination of trace levels of Cd, Co, Cr, Fe, Mn, Ni, and Pb by flame atomic absorption spectrometry using a column preconcentration system is described in which the metals were adsorbed on pulverized banana peel, an economically and environmentally acceptable sorbent. In the optimization procedure, five variables (sample pH, mass of biosorbent, type of eluent, sample flow rate, and volume) were optimized and the capacity of the biosorbent was established. Under the optimized conditions, the detection limits of the method were 2.4, 27.0, 49.4, 31.1, 6.7, 29.6, and 46.2 µg L−1 for Cd, Co, Cr, Fe, Mn, Ni, and Pb, respectively. The precision, expressed as relative standard deviation, was less than 4% based on twelve measurements. The recoveries were 81.1% (Cd), 91.4% (Co), 87.2% (Cr), 90.1% (Fe), 88.0% (Mn), 94.1% (Ni), and 93.2% (Pb) under the optimum conditions (pH; 9, sample flow rate; 3 mL min−1, mass of biosorbent; 200 mg; eluent; 1 mol L−1 nitric acid, preconcentration factor; 10). The sorption capacity of pulverized banana peel was 15.12, 28.85, 32.70, 30.44, 30.94, 28.97, and 8.21 µmol per gram of adsorbent for Cd, Co, Cr, Fe, Mn, Ni, and Pb, respectively.

Correlation between water hardness and cardiovascular diseases in Mostar city, Bosnia and Herzegovina

The aim of this study was to determine the association of cardiovascular disease (CVD) of selected human subjects with the hardness of water they consume. Laboratory testing of physical and chemical parameters of water were made using standardized methods: Standard Methods 19th edn, 1995 (APHA, AWWA & WEF, Washington, DC), and ISO 7888:1985, ISO 10523:1998. Pearsons chi-squared test was used for the statistical analysis of data, with the significance level of 0.05. The obtained data were analysed using the statistical program SPSS 16.0. The study sample consisted of 1,021 individuals divided into two groups: soft water consumers, 603 individuals, and, hard water consumers, 618 individuals. Results indicate that a statistically significant (χ(2) = 5.315; df = 1; p = 0.021) number of individuals with CVD drink soft water. The prevalence of CVD in the age group 45-60 years in the study area where soft water is consumed was 21.3% and in the study area where hard water is consumed the prevalence of CVD was 13.7%. The summary results indicate significant correlation between the prevalence of CVD in the population group who drink soft water. The value of the relative risk is 1.127.

Characterization of Mercury Contamination Surrounding a Chloralkali Production Facility in Tuzla, Bosnia and Herzegovina

ABSTRACT Tuzla is among the most polluted cities of Bosnia and Herzegovina. The main source of pollution in the area is soil heavily contaminated by mercury released from a former chloralkali plant. This paper is focused on the characterization of mercury contaminated soil and air surrounding the chloralkali plant. In soil, the mobility and transformation of mercury were investigated by sequential extraction, while the methylation and reduction potentials were determined by the use of a radioactive tracer. Mercury emission from soil was determined by laboratory and by flux chamber measurements in the field. In addition, mercury concentrations in air were estimated by the analysis of air and the transplanted lichen Hypogymnia physodes. Mercury in soils in the vicinity of the chloralkali plant exceeded the background value by a factor of more than 3000. The fractionation of mercury in surface soil by sequential extraction showed that the mercury in soil was primarily bound to organic matter and a fraction containing elemental mercury and mercury (I) chloride is also significant. The obtained methylation and reduction potentials are low. The mercury flux from soil was estimated by two approaches. Fluxes of up to 8000 ng/m2/day were measured at the most polluted site; evaporation from soil was shown to be the primary source of elevated mercury in air. Air concentration mapping also revealed other sources of mercury; the most likely is the 715 MW coal power plant in the vicinity of former chloralkali facility.

Sorption of Metals on Pulverized Pumpkin (Cucurbita pepo L.) Peels

ABSTRACT The pulverized peel of unmodified and modified pumpkin (Cucurbita pepo L.) was used as sorbent for the determination of Cd, Co, Cr, Fe, Mn, Ni, and Pb by flame atomic absorption spectrometry. The parameters affecting the preconcentration efficiency were investigated. The optimal conditions for preconcentration on unmodified pumpkin peel were identical to those using modified peel: a pH of 8, a preconcentration factor of 10, a flow rate of 3 mL min−1, and an eluent concentration of 1 mol L−1 for all analytes. The detection limits of the method were 9.2, 8.8, 13.2, 28.7, 6.6, 7.6, and 16.5 µ g L−1, while the quantification limits were 30.6, 29.2, 43.9, 95.5, 22.1, 25.4, and 55.1 µ g L−1 for Cd, Co, Cr, Fe, Mn, Ni, and Pb, respectively. The accuracy of the method was verified with a certified reference material. The relative standard deviation was less than 4% based on 12 measurements. Under the optimum conditions of preconcentration, the recovery values exceeded 94%. The following capacity order was obtained for the analytes (µmol g−1): Ni2+ > Co2+ > Fe3+ > Mn2+ > Cr3+ > Cd2+ > Pb2+.

Determination of total and bioaccessible metals in airborne particulate matter from an urban and a rural area at Sarajevo

ABSTRACT Airborne particulate matter of up to 10 µm collected at an urban and a rural area at Sarajevo in 2013 and 2014 was acid digested for determination of total concentrations or extracted with synthetic gastric juice for the bioaccessible fractions of Cd, Cr, Cu, Fe, Mn, Ni, Pb, V, and Zn and determined by graphite furnace and flame atomic absorption spectrometry. The total concentrations of Cr, Cu, Fe, Mn, Pb, and V were higher at the urban site, while those of Cd, Ni, and Zn were virtually equal at both sites. The average bioaccessible fractions exhibited the following trend at both sites: Fe > Zn > Cu > Mn > Pb > Cr > V > Ni > Cd. Enrichment factors and daily intake of metals by inhalation were calculated.

Chemical Analysis of Iron Slags and Metallic Artefacts from Early Iron Age

Eight samples of iron slag and two metallic artefacts from two Early Iron Age sites in central Bosnia and Herzegovina, ��olaci and Pod, were analysed using chemical instrumental methods. Atomic absorption spectrometry was applied to determine major (Fe, Al,Ca, Na, Mg, K and Mn) and trace elements (Cr, Cu, Co, Ni and Zn), while gravimetric method and molecular visible spectrometry were applied to determine Si and Ti, respectively. Infrared spectrum of selected samples was recorded during different phases ofanalysis and the results show that the primary ore was hematite. Results also indicate that residents from both sites, which are adjacent, used the same ore source. Low values of Ca, whose compounds are used as flux in later stages of the processing of iron ore, show that the processing of iron at the study sites was in the beginning stage of its development.Based on the obtained results, metallic artefacts found at the site ��olaci probably came from site Pod. Graphical presentation of the content relation ship between the selected metal oxides in the slag was preformed to present differences between samples from two sites. Analysis of trace elements in the analysed slags confirmed that they originate from Early Iron Age.