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Rischi lavorativi in una azienda produttrice di ruote in lega di alluminio.
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An environmental hygiene study was carried out in a factory making aluminium alloy wheels via pressure moulding. Physical risk factors (noise and microclimate) and chemical risk factors (respirable dust, mineral oils, solvents, fluorides, formaldehyde, CO) were assessed. Analysis of the data showed that physical risk factors were prevalent, whereas chemical pollution was insignificant due to technical improvements made by the management in the course of several redesigns of the plants
High-performance liquid chromatographic determination of urinary 2,5-hexanedione ad mono-2,4-dinitrophenylhydrazone using ultraviolet detection.
No full textAbstract
The good correlation between exposure to n-hexane and 2,5-hexanedione urinary excretion confers on this diketone an important toxicological meaning. This paper proposes a reversed-phase HPLC method which includes, after acid hydrolysis, a derivatization step of 2,5-hexanedione with 2,4-dinitrophenylhydrazine at 70°C for 20 min. The reaction conditions, such as temperature, reagent concentration and time, are optimized so as to allow the condensation of a single carbonyl group. A linear response was obtained in the 0.19-20.0 mg/l range with a detection limit of 0.03 mg/l, corresponding to a signal-to-noise ratio of 3. A phosphate buffer (pH 3.3)-acetonitrile mixture (50:50) as the eluent and UV detection at 334 nm were used
HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC DETERMINATION OF METHYL ETHYL KETONE IN URINE AS ITS 3-METHYL-2-BENZOTHIAZOLINONE HYDRAZONE DERIVATIVE
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A HPLC method for the determination of methyl ethyl ketone (MEK) in urine after derivatization with 3-methyl-2-benzothiazolinone hydrazone is proposed. The calibration curve for the ketone was linear, ranging between 0.23-10 mg/L, with a detection limit of 0.025 mg/L. The results were compared to those obtained by GC-MS, coupled to the headspace technique. MEK derivatization and the derivative purification processes were verified with respect to the main variables such as reaction temperature, reagent concentration, probable interferences and enrichment phase. The method is simple and reliable and shows a good sensitivity
Biological monitoring of exposure to n-heptane by gas chromatographic mass spectrometric determination of its metabolites
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Urine samples from 10 workers that had been exposed to n-heptane were analysed by the GC/MS technique to verify the concentrations and the relative abundances of its metabolites. The procedure of sample preparation has undergone some modifications with respect to the Perbellini method and the mass spectrometric detection was carried out in selected ions monitoring conditions. The analyses of samples collected during three different workshifts showed that 2-heptanol was not the main metabolite and that the remains of 2-heptanone, valerolactone and 2,5-heptanedione were present at the beginning of the successive work-week at 12, 34 and 39% of the average values found at the end of the previous week. Overall, a very slow excretion rate was detected for the last metabolite. The main and significant metabolite at the end of the two workshifts was 2-heptanone which was detected in urine at average values of 413 and 238 μg g-1 creatinine. This urinary ketone correlated better than other metabolites with respect to the airborne n-heptane at the end of both the workshift and work-week. These preliminary data suggest that further studies should be carried out to confirm whether 2-heptanone is really useful as an n-heptane marker in biological monitoring
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