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Health-care workers handling antineoplastic agents may be exposed to extremely low doses of these drugs. Very sensitive and specific analytical methods are therefore needed for biological monitoring. The aim of this study was to develop and validate a method for trace level determination of doxorubicin, epirubicin, daunorubicin and idarubicin in human urine, using epi-daunorubicin as an internal standard. Solid-phase extraction (SPE) was used for sample preparation. Urine samples were loaded onto Bond Elut C18 cartridges. The analytes were eluted in methylene chloride/2-propanol (1:1, v/v) and then evaporated to dryness. The residue was reconstituted with the mobile phase prior to high-performance liquid chromatography/tandem mass spectrometry (HPLC/MS/MS) analysis. Quantitation of each analyte was performed using the multiple reaction monitoring (MRM) method. The urine assay was linear over the range 0.1-2.0 microg/L, with a lower limit of quantification (LLOQ) of 0.10 microg/L for doxorubicin and epirubicin, and 0.03 microg/L for daunorubicin and idarubicin. The respective limits of detection (LODs) were 0.04 and 0.01 microg/L. The precision and accuracy of the assay were determined on three different days. The within-series precision was found to be always less than 13.9% for all the analytes. The overall precision expressed as relative standard deviation (RSD) was always less than 10.6%. The recovery of anthracyclines was assessed at two concentrations of the range tested (0.1 and 2.0 microg/L) and it ranged from 87.7% (daunorubicin) to 102.0% (doxorubicin) and from 79.1% (daunorubicin) to 90.7% (idarubicin) for the lower and the higher level, respectively, with a RSD always less than 9.1%. The uncertainty of the present assay was also evaluated and the combined uncertainty was always less than 20% over all the days of the validation study. This is the first method that makes use of LC/MS/MS for the biological monitoring of occupational exposure to anthracyclines.

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In recent years identification of the geographical origin of food has grown more important as consumers have become interested in knowing the provenance of the food that they purchase and eat. Certification schemes and labels have thus been developed to protect consumers and genuine producers from the improper use of popular brand names or renowned geographical origins. As the tomato is one of the major components of what is considered to be the healthy Mediterranean diet, it is important to be able to determine the geographical origin of tomatoes and tomato-based products such as tomato sauce. The aim of this work is to develop an analytical method to determine rare earth elements (RRE) for the control of the geographic origin of tomatoes. The content of REE in tomato plant samples collected from an agricultural area in Piacenza, Italy, was determined, using four different digestion procedures with and without HF. Microwave dissolution with HNO3 + H2O2 proved to be the most suitable digestion procedure. Inductively coupled plasma quadrupole mass spectrometry (ICPQMS) and inductively coupled plasma sector field plasma mass spectrometry (ICPSFMS) instruments, both coupled with a desolvation system, were used to determine the REE in tomato plants in two different laboratories. A matched calibration curve method was used for the quantification of the analytes. The detection limits (MDLs) of the method ranged from 0.03 ng g(-1) for Ho, Tm, and Lu to 2 ng g(-1) for La and Ce. The precision, in terms of relative standard deviation on six replicates, was good, with values ranging, on average, from 6.0% for LREE (light rare earth elements) to 16.5% for HREE (heavy rare earth elements). These detection limits allowed the determination of the very low concentrations of REE present in tomato berries. For the concentrations of REE in tomato plants, the following trend was observed: roots > leaves > stems > berries.

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Trace elements in fuel oils have been analysed by inductively coupled plasma mass spectrometry (ICP-MS) after acid solubilization of the samples in a microwave oven. The results relative to the National Institute of Standards and Technology SRM 16341, and SRM 1619 show good accuracy and precision for about 20 elements. The detection limits are, for most of the elements, in the range 0.02-0.2 pg g-'; values that are consistent with the concentrations of metallic impurities present in fuel oils. The good agreement obtained on real samples using neutron activation analysis is a demonstration that ICP-MS can compete with a well established reference technique for the determination of trace metals in fuel oil.

A direct, rapid and selective method for the quantitative determination of the ethylenethiourea (ETU) in human urine has been validated and is reported in the present study. It allows the accurate quantification of ETU in this complex matrix without the use of any internal standard as the sample cleanup is effective enough for the removal of interferences that could lead to ion suppression in the electrospray ionization (ESI) source. This simple and rapid purification system, based on the use of a Fluorosil phase of a BondElut column followed by a liquid-liquid extraction procedure, achieves mean extracted recoveries, assessed at three different concentrations (2.5, 10.0, and 25.0 microg/L), always more than 85%. High-performance liquid chromatography (HPLC) with positive ion tandem mass spectrometry, operating in selected multiple reaction monitoring (MRM) mode, is used to quantify ETU in human urine. The assay is linear over the range 0-50 microg/L, with a lower limit of quantification (LOQ) of 1.5 microg/L and a coefficient of variation (CV) of 8.9%. The lower limit of detection (LOD) is assessed at 0.5 microg/L. The overall precision and accuracy were determined on three different days. The values for within- and between-day precision are < or = 8.3 and 10.1%, respectively, and the accuracy is in the range 97-118%. The relative uncertainties for the LOQ and QC concentrations have been estimated to be 18 and 8%, respectively. The assay was applied to quantify ETU in human urine from growers that regularly handle ethylenebisdithiocarbamate pesticides in large crop plantations. The biological samples were collected at the start and end of the working day, and the ETU urine levels were found to vary between 1.9 and 8.2 microg/L.