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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.

J. Sulejmanović, T. Muhic-Sarac, M. Memić, A. Gambaro, A. Selović

A study of the atmospheric particulate size distribution of total suspended particulate matter(TSPM) and associated heavy metals concentrations has been carried out for the urban part of Sarajevo city,Bosnia and Herzegovina. Urban particles (n=150) were collected using a high volume air sampler equippedwith a 6-stage impactor. Apart from Fe which has been determined by flame atomic absorption spectrometry(FAAS), all measurements (Co, Cu, Mn) have been carried out by graphite furnace atomic absorptionspectrometry (GFAAS). The average concentrations of particulate matter are 37%, 18%, 15%, 8%, 15% and6% (averaged over all the observations) of total suspended particulate for PM 7.2, respectively. Metal concentrations in size-fractionated urban particles ranged from 0.01-3.83 ng/m3 for Co, 6.30-179.20 ng/m3 for Cu, 5.00-208.70 ng/m3 for Mn and 0.35-6.82 g/m3 for Fe. Major concentrations of investigated metals are associated with the PM 7.2-3.0 μm. Overall, the decreasing trend of average trace element concentrations (24-h) in the particulates revealed the following order: Fe>Mn>Cu>Co.

S. Pieri, A. Arruti, J. Huremović, J. Sulejmanović, A. Selović, Dragana S Ðorđević, I. Fernández-Olmo, A. Gambaro

Environmental contamination by polycyclic aromatic hydrocarbons (PAHs) has caused increasing concern because of their known, or suspected, carcinogenic and mutagenic effects. Polycyclic aromatic hydrocarbons occurring in the environment are usually the result of the incomplete combustion of carbon containing materials. The main sources of severe PAHs contamination in soil come from fossil fuels, i.e. production or use of fossil fuels or their products, such as coal tar and creosote. Creosote is used as a wood preservation for railway ties, bridge timbers, pilling and large-sized lumber. It consists mainly of PAHs, phenol and cresol compounds that cause harmful health effects. Research on biodegradation has shown that a special group of microorganisms, the white-rot fungi and brown-rot fungi, has a remarkable potential to degrade PAHs. This paper presents a study of the antifungal activity of 12 selected PAHs against two ligninolytic fungi Hypoxylon fragiforme (white rot) and Coniophora puteana (brown rot). The antifungal activity of PAHs was determined by the disc-diffusion method by measuring the diameter of the zone of inhibition. The results showed that the antifungal activity of the tested PAHs (concentration of 2.5 mmol/L) depends on the their properties such as molar mass, solubility in water, values of log Kow, ionization potential and Henry’s Law constant as well as number of aromatic rings, molecule topology or pattern of ring linkage. Among the 12 investigated PAHs, benzo(k) fluoranthene with five rings, and pyrene with four cyclic condensed benzene rings showed the highest antifungal activity.

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