Zn- vs Bi-based oxides for o-toluidine photocatalytic treatment under solar light.

The photodegradation of the highly toxic o-toluidine pollutant was deeply investigated both under UV and solar irradiations by using three different semiconductors: pure ZnO, Bi-impregnated ZnO, and Bi2O3 nanopowders (synthesized by precipitating method). All the samples were deeply characterized on structural, morphological, surface, and optical points of view. The disappearance and the relative mineralization of o-toluidine molecules were followed by linear sweep voltammetry (LSV) and total organic carbon (TOC) determinations, respectively. Hence, correlations between their physico-chemical properties and the photocatalytic performances, passing from UV to solar light, were drawn and a hypothesis on the photodegradation mechanism has been proposed, on the basis of the HPLC/MS results. Bare Bi2O3 samples, due to the exploitation of both their visible light absorption and the negligible intermediates formation, resulted to be higher performing under solar irradiation than either pure or Bi-doped ZnO nanopowders. Graphical abstract.

3D Mass Spectrometry Imaging Reveals a Very Heterogeneous Drug Distribution in Tumors.

Mass Spectrometry Imaging (MSI) is a widespread technique used to qualitatively describe in two dimensions the distribution of endogenous or exogenous compounds within tissue sections. Absolute quantification of drugs using MSI is a recent challenge that just in the last years has started to be addressed. Starting from a two dimensional MSI protocol, we developed a three-dimensional pipeline to study drug penetration in tumors and to develop a new drug quantification method by MALDI MSI. Paclitaxel distribution and concentration in different tumors were measured in a 3D model of Malignant Pleural Mesothelioma (MPM), which is known to be a very heterogeneous neoplasm, highly resistant to different drugs. The 3D computational reconstruction allows an accurate description of tumor PTX penetration, adding information about the heterogeneity of tumor drug distribution due to the complex microenvironment. The use of an internal standard, homogenously sprayed on tissue slices, ensures quantitative results that are similar to those obtained using HPLC. The 3D model gives important information about the drug concentration in different tumor sub-volumes and shows that the great part of each tumor is not reached by the drug, suggesting the concept of pseudo-resistance as a further explanation for ineffective therapies and tumors relapse.

Hazardous o-toluidine mineralization by photocatalytic bismuth doped ZnO slurries.

Photocatalytic mineralization of o-toluidine in aqueous media under UV/solar irradiation was achieved by bare and bismuth doped zinc oxide nanoparticles. By adopting different analytical approaches a reaction mechanism is proposed, explaining the differences in photodetoxification performances.

Olfactory and toxic impact of industrial odour emissions.

This paper describes the approach adopted for the evaluation both of the odour impact and of the non-carcinogenic health effects relevant to odours in the city of Terni, Italy. The first part of the study focused on the quantification of emissions by means of dynamic olfactometry and chemical analyses. Dispersion modelling was then applied for the evaluation of citizens' exposure both to odours and to their non-carcinogenic toxicity. The results show that, on one hand, the odour impact is considerable, actually affecting almost the whole city of Terni. On the other hand, the toxic impact, expressed in terms of the Hazard Index (HI), is about three orders of magnitude lower than the level that is expected to bring adverse effects, over a lifetime exposure, for human health.

Evaluating the dispersion of toxic odour emissions from complex sources.

This article describes an original approach for evaluating exposure to toxic odour emissions, based on methods commonly used for assessing the impact of odour, adopted in this specific case to examine the non-carcinogenic health effects of odours in the city of Terni, Italy. First the hazardous volatile organic compounds emitted from the main odour sources were identified and quantified by chemical analysis. The Hazard Index (HI) was used to assess the toxicity associated with the emissions. The HI is the sum of the concentrations of the hazardous compounds weighted with their Reference Concentration (RfC). A RfC is the estimated continuous inhalation concentration at which people are unlikely to risk any deleterious effects during their lifetime. Atmospheric dispersion modelling was based on the Toxicity Emission Rate (TER) which, like the Odour Emission Rate (OER) conventionally used to quantify odour emissions, relates the HI with the air flow of an emission source; it is as a simple but effective method for the general characterization of toxic odour emissions in complex scenarios. The results indicated that citizens' exposure to the non-carcinogenic toxic compounds involved in odour emissions was below the level expected to have adverse effects on human health. Classical risk assessment techniques should now be employed to define the pollutants and their effects better and to validate this approach.

Odours and volatile organic compounds emitted from municipal solid waste at different stage of decomposition and relationship with biological stability.

Odours (OU(E)) and volatile organic compounds (VOC) emission during biological process used to treat MSW were studied under standardized conditions in order to detect potential risk for workers and population. Results obtained indicated that odours and VOCs emitted depend on the biological stability of waste measured by the dynamic respiration index (DRI) and a very good correlation were found between these parameters (OU(E) vs. DRI, r=0.96, p<0.001, n=6; VOC vs. DRI, r=0.97, p<0.001, n=6). GC-MS study of the VOCs indicated the presence of a group of molecules that were degraded during the process. On the other hand, a second group of molecules, i.e. aromatic and halogenated compounds, and furan persisted in the waste sample, although molecule concentrations were always lower than Threshold Limit Value-Time Weighted Average (TLV-TWA).

Evaluation of selected ubiquitous contaminants in the aquatic environment and their transformation products. A pilot study of their removal from a sewage treatment plant.

A simple method using direct sample injection combined with liquid chromatography tandem mass spectrometry has been developed for the simultaneous analysis of six alkaloid compounds in environmental samples. The target list includes two psychostimulants (nicotine and caffeine), three metabolites (cotinine, nicotinic acid and paraxanthine) and a coffee chemical (trigonelline). The analytical method was evaluated in three different matrices (surface water, influent and effluent wastewater). The method developed showed an adequate sensitivity, below 0.6 µg L(-1) for wastewater and 0.1 µg L(-1) for river matrices, without any prior treatment of the samples. Finally, the methodology was applied to real samples for evaluation of their removal from a sewage treatment plant and their persistence/fate in the aquatic environment. All compounds studied in this work were detected at all sampling points collected along the Henares River. However, nicotinic acid was only detected three times in treated sewage samples at levels above its detection limit.

Potential odour emission measurement in organic fraction of municipal solid waste during anaerobic digestion: Relationship with process and biological stability parameters.

The aim of the present study is to investigate the correlation between microbial activity, i.e., biological stability measured by aerobic (OD(20) test) and anaerobic tests (ABP test), and odour emissions of organic fraction of municipal solid waste during anaerobic digestion in a full-scale treatment plant considering the three stages of the process (input, digested and post-digested waste). The results obtained indicated that the stabilization of the treated material reduces the odour impact measured by the olfactometric approach. Successive application of gas chromatography mass spectrometry (GC-MS) and electronic nose (EN) allowed the characterization of the different groups of volatile organic compounds (VOCs) responsible of odour impacts determining, also, their concentration. Principal component and partial least squares analyses applied to the EN and GC-MS data sets gave good regression for the OD(20) vs the EN and OD(20) vs the GC-MS data. Therefore, OD(20) reduction could be used as an odour depletion indicator.

Potential odour emission measurement in organic fraction of municipal solid waste during anaerobic digestion: relationship with process and biological stability parameters.

The aim of the present study is to investigate the correlation between microbial activity, i.e., biological stability measured by aerobic (OD20 test) and anaerobic tests (ABP test), and odour emissions of organic fraction of municipal solid waste during anaerobic digestion in a full-scale treatment plant considering the three stages of the process (input, digested and post-digested waste). The results obtained indicated that the stabilization of the treated material reduces the odour impact measured by the olfactometric approach. Successive application of gas chromatography mass spectrometry (GC-MS) and electronic nose (EN) allowed the characterization of the different groups of volatile organic compounds (VOCs) responsible of odour impacts determining, also, their concentration. Principal component and partial least squares analyses applied to the EN and GC-MS data sets gave good regression for the OD20 vs the EN and OD20 vs the GC-MS data. Therefore, OD20 reduction could be used as an odour depletion indicator.

Waste management health risk assessment: a case study of a solid waste landfill in South Italy.

An integrated risk assessment study has been performed in an area within 5 km from a landfill that accepts non hazardous waste. The risk assessment was based on measured emissions and maximum chronic population exposure, for both children and adults, to contaminated air, some foods and soil. The toxic effects assessed were limited to the main known carcinogenic compounds emitted from landfills coming both from landfill gas torch combustion (e.g., dioxins, furans and polycyclic aromatic hydrocarbons, PAHs) and from diffusive emissions (vinyl chloride monomer, VCM). Risk assessment has been performed both for carcinogenic and non-carcinogenic effects. Results indicate that cancer and non-cancer effects risk (hazard index, HI) are largely below the values accepted from the main international agencies (e.g., WHO, US EPA) and national legislation (D.Lgs. 152/2006 and D.Lgs. 4/2008).

PCB concentrations in some foods from four European countries.

Samples of salmon, butter and cabbage from Belgium, Italy, Spain and Portugal were analysed for their content in total, non-dioxin-like (as represented by the so-called seven indicator-PCBs: congeners 28, 52, 101, 118, 138, 153 and 180) and dioxin-like PCBs (mono-ortho and non-ortho PCBs). Salmon and cabbage from Belgium, and butter from Portugal and Belgium, contained less total and non-dioxin-like PCBs than those from other countries. Samples from Italy had the highest concentrations. Similar patterns were observed for dioxin-like PCBs (as represented by the TCDD-equivalents of toxicity, WHO-TEQs), with the lowest values in Belgium and Portugal for salmon, in Portugal for butter and in Belgium for cabbage. Differences up to five-fold in PCB concentrations and TEQ values were seen among commodities from the four countries. The implication is that it might be worthwhile monitoring, with selection of the least contaminated commodities, to reduce the PCB exposure of the general population. This could have health consequences, because daily intakes are higher than the tolerable levels for a considerable part of the European population.

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Characterisation of odorants emissions from landfills by SPME and GC/MS.

Odorous compounds from a landfill have been characterised by gas-chromatography-mass-spectrometry, identifying about 100 volatile organic compounds. Air samples from different landfill sites and from the environment have been analysed after a solid-phase microextraction on a three-phase fiber, DVB/Carboxen/PDMS, which allowed a preconcentration and the chromatographic data obtained from the most significant emission sources have been submitted to chemometric analysis in order to better establish specific markers of olfactory pollution. For example limonene was a typical tracer of fresh wastes, while p-cymene was characteristic of leachate and biogas. By the developed analytical procedure it has been evaluated the efficiency of a scrubber plant utilised in the landfill in order to remove malodour compounds. The average removal efficiency was not very high (about 23.5%) due to scarce ability in removing low polarity compounds. Furthermore, it has been demonstrated the suitability of a microgas chromatograph for the continuous on-site monitoring of air pollution in order to rapidly individuate emission sources of olfactive nuisances.

Evaluation of the PrimeCapture CMV DNA detection plate system for detection of cytomegalovirus in clinical specimens.

With the availability of anticytomegalovirus (CMV) therapeutic agents, rapid detection of CMV is important in the care and management of the immunosuppressed patient. The PrimeCapture CMV DNA Detection Plate System (PC-PCR) was evaluated for the detection of CMV in blood and cerebrospinal fluid (CSF). The resolution of discordant results was performed by consensus testing utilizing a combination of conventional cell culture (TC-CPE), the CMV-antigenemia (CMV-Ag) assay, one or more in-house CMV nested PCR assays, and/or patient evaluation and follow-up. Of 51 blood specimens from 34 patients, 23 (45%) were identified as true positives. PC-PCR was significantly more sensitive than the CMV-Ag assay, TC-CPE, or a combination of both tests. The sensitivities, specificities, positive predictive values (PPV), and negative predictive values (NPV) for PC-PCR, the CMV-Ag assay, TC-CPE, and a combination of CMV-Ag and TC-CPE were 78, 75, 72, 81%; 46, 100, 100, 70%; 39, 100, 100, 67%; and 58, 100, 100, 73%, respectively. CMV was not detected or isolated in CSF, resulting in a combined PC-PCR sensitivity, specificity, PPV, and NPV of 77, 90, 68, and 93%, respectively. Among those laboratorians considering the incorporation of molecular CMV diagnostics into their clinical microbiology or virology laboratories, the CMV PC-PCR offers a relatively simple-to-perform and sensitive assay system.

Rapid solid-phase extraction method for automated gas chromatographic-mass spectrometric determination of nicotine in plasma.

The aim of this study was to develop a simple, rapid and sensitive assay of nicotine in plasma for automated gas chromatographic-mass spectrometric analysis. Biological samples were extracted using pre-packed Extrelut-1 columns with 5 ml of ethyl acetate. Quantitative analysis was done using deuterium-labelled nicotine as internal standard. The limit of quantitation was 0.5 ng in 1-ml plasma samples. Precision was ranging from 13.3% to 1.64% (R.S.D.) depending on the concentration, while the deviation was 4.16%. This method has been used for determination of nicotine bioavailability from new, low-dosage, nicotine chewing gum strips.

Industrial pollutants in ground waters from northern Milan.

Ground water samples from an industrialised area near Milan were analysed by gas chromatography-mass spectrometry (GC-MS) to identify the main pollutants and to quantify two classes of chemicals: polychloro-1,3-butadienes (PCBD) and some aromatic amines. The water contained several halogenated aromatic and aliphatic compounds and heavy contamination due to PCBD, probably arising from contaminated land where a disused chemical plant is located. All the samples contained low levels of aromatic amines indicating a diffuse contamination probably arising from different sources.

Validity of self-reported smoking habits in pregnancy: a saliva cotinine analysis.

BACKGROUND: We examined the validity of self-reported cigarette smoking during the third trimester of pregnancy using saliva cotinine as a marker. METHODS: Eligible for the study were 109 pregnant women attending the outpatient Prenatal Service of the Luigi Mangiagalli Clinic (the largest maternity clinic in Milan) for routine prenatal visits during the third trimester of pregnancy on twenty days in 1994. Women self-reporting current smoking or quitting smoking in pregnancy were asked to provide a saliva sample. Cotinine concentration was analyzed and classified as follows: cotinine not detectable, not probable nicotine use or passive exposure; cotinine <10 ng/ml, not probable nicotine use/probable passive exposure; cotinine, > or = 10 ng/m, probable occasional or regular nicotine use. RESULTS: A total of 57 (52.3%) women were non-smokers at conception and were excluded from any subsequent analysis. Of the remaining 52 women, 25 self-reported quitting smoking in pregnancy and 27 were current smokers. Saliva cotinine levels were below 10 in 20 of the 25 subjects reporting quitting smoking in pregnancy. The five cases with cotinine > or = 10 reported a husband smoking more than 10 cigarettes per day. Among the 26 current smokers, seven had a cotinine level <10 ng/ml (four reported smoking fewer then five cigarettes per day and two reported smoking five or more per day); in 20 cases the cotinine value was > or = 10 ng/ml. CONCLUSIONS: These findings provide evidence of a satisfactory validity of self-reported smoking habits in pregnancy.

On-line monitoring of benzene air concentrations while driving in traffic by means of isotopic dilution gas chromatography/mass spectrometry.

There is no shortage of information about the average benzene concentrations in urban air, but there is very little about microenvironmental exposure, such as in-vehicle concentrations while driving in various traffic conditions, while refuelling, or while in a parking garage. The main reason for this lack of data is that no analytical instrumentation has been available to measure on-line trace amounts of benzene in such situations. We have recently proposed a highly accurate, high-speed cryofocusing gas chromatography/mass spectrometry (GC/MS) system for monitoring benzene concentrations in air. Accuracy of the analytical data is achieved by enrichment of the air sample before trapping, with a stable isotope permeation tube system. The same principles have been applied to a new instrument, specifically designed for operation on an electric vehicle (Ducato Elettra, Fiat). The zero emission vehicle and the fully transportable, battery-operated GC/MS system provide a unique possibility of monitoring benzene exposure in real everyday situations such as while driving, refuelling, or repairing a car. All power consumptions have been reduced so as to achieve a battery-operated GC/MS system. Liquid nitrogen cryofocusing has been replaced by a packed, inductively heated, graphitized charcoal microtrap. The instrument has been mounted on shock absorbers and installed in the van. The whole system has been tested in both fixed and mobile conditions. The maximum monitoring period without external power supply is 6 h. The full analytical cycle is 4 min, allowing close to real-time monitoring, and the minimum detectable level is 1 microgram/m3 for benzene. In-vehicle monitoring showed that, when recirculation was off and ventilation on, i.e., air from outside the vehicle was blown inside, concentrations varied widely in different driving conditions: moving from a parking lot into normal traffic on an urban traffic condition roadway yielded an increase in benzene concentration from 17 to 62.3 micrograms/m3 even if the actual distance was small. A larger increase was observed when a car was left with the engine running at a distance 2 m from the zero emission vehicle: We measured an increment of benzene concentrations from 15.2 to 174.4 micrograms/m3 with a car equipped with a catalytic converter, and from 19.1 to 386.3 micrograms/m3 with a car without such a converter.

Automated high-speed analysis of selected organic compounds in urban air by on-line isotopic dilution cryofocusing gas chromatography/mass spectrometry.

An automated environmental air monitor has been developed to measure selected organic compounds in urban air. The instrument is based on a cryofocusing-thermal desorption gas chromatographic mass spectrometry technique where the mass spectrometer is a slightly modified residual gas analyzer (RGA). The RGA was chosen as a detector because the whole system must be robust for long periods, with 24-h continuous air monitoring. RCA are extremely simple and seemed the most reliable mass spectrometers for this purpose. Moreover, because they have no physically limited ion source, contamination is considerably reduced, so maintenance intervals are longer.The gas chromatograph is equipped with a computer-controlled six-way sampling valve, with a 100-mL sampling loop and thermal desorption cold trap injector. Environmental air is enriched with an isotopically labeled internal standard in the sampling line. This internal standard is added with a validated, custom-made, permeation tube device. The "on-line" internal standard provides for high quality quantitative data because all variations in instrument sensitivity in cryofocusing or in thermal desorption efficiency are taken into account. High repetition rates (down to 5 min for a full analytical cycle) are obtained with the use of an isothermal gas chromatography program, microbore capillary column, and environmental air sampling during the gas chromatography run.

Purification and analysis of drug residues in urine samples by on-line immunoaffinity chromatography/high-performance liquid chromatography/continuous-flow fast atom bombardment mass spectrometry.

An automatic system for the on-line extraction and analysis of diethylstilbestrol in the urine of rats and calves is described. Extraction was done by injecting samples directly into an immunoaffinity column containing antidiethylstilbestrol antibodies bound to a Sepharose matrix, and analysis was done by on-line high-performance liquid chromatography with ultraviolet and continuous-flow fast atom bombardment mass spectrometry detectors. The system, consisting of one injector, two switching valves, and three pumps, was operated under computer control and allowed to perform a complete analysis of a sample in 28 min. An accurate quantitation by isotope dilution was also possible, by the use of deuterated diethylstilbestrol as internal standard. The sensitivity of the method, using selected-ion monitoring of the molecular ion of diethylstilbestrol, was 2 ng/mL, injecting 1 mL of urine sample. Results obtained from analyzing the urine of rats and calves treated with diethylstilbestrol are presented.