Diana Poli

Università degli Studi di Brescia, Brescia, Lombardy, Italy

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Publications (43)94.72 Total impact

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    ABSTRACT: This cross-sectional study was aimed at reconstructing the exposure to gasoline in 102 petrol station attendants by environmental and biological monitoring of benzene, toluene, ethylbenzene and xylene (BTEX) and biomonitoring of methyl tert-butyl ether (MTBE). Airborne BTEX were higher for manual refuelers than self-service assistants and were highly correlated with each other. Significant relationships were found between airborne BTX and the corresponding urinary solvents (U-BTX) and beween airborne B and urinary MTBE (U-MTBE). Smokers eliminated higher values of U-B, trans,trans-muconic (t,t-MA) and S-phenylmercapturic (S-PMA) acids but not U-MTBE. All these biomarkers were, however, significantly raised during the shift, independently from smoking. Linear regression confirmed that occupational exposure was a main predictor of U-MTBE, U-B and S-PMA values, both the latter confounded by smoking habits. The study supports the usefulness of biomonitoring even at low exposure levels.
    Biomarkers 03/2012; 17(4):343-51. · 1.88 Impact Factor
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    ABSTRACT: PM(2.5) generated by indoor combustion activities can contribute significantly to personal PM exposure. The aims of this study were: (1) to validate a device specifically designed to study the kinetics of particle exhalation and the percentage of airway particle deposition (%DEP) in polluted indoor environments (welding fumes, environmental tobacco smoke - ETS) and (2) to assess the intra- and inter-subject variability of the signal. The device was tested on 14 subjects exposed to welding fumes and 10 subjects exposed to environmental tobacco smoke (ETS), performing repeated measures at different environmental PM concentrations. The intra-subject variability of the signal for particles with diameter 0.3-1.0 μm showed a geometric mean of %CV always below 6%, despite the values of %DEP. In the welding fume study, the increase in airborne 0.5-1.0 μm PM concentrations between the consulting room and production department was explainable in terms of increased density due to the metallic composition of particles. The %DEP of 0.3-1.0 μm ETS particles decreased with airborne PM concentration due to the technical limits of a laser particle counter and the perturbation induced by the physical characteristics of ETS PM. However, also at those extreme conditions, the signal remained repeatable and the individual susceptibility to PM remained substantially unaltered. In conclusion, the versatility and portability of our device, together with the repeatability of the signal, confirmed that the kinetics of exhaled particles and %DEP could be routinely measured in polluted environments and used to define individual susceptibility to airborne particles.
    International journal of hygiene and environmental health 12/2011; 215(3):312-9. · 2.64 Impact Factor
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    ABSTRACT: MeHg (0.5 mg/kg/day) and/or PCB153 (5 mg/kg/day) effects, administered orally to rat dams (GD7-PND21), were explored in PND21 and PND36 offspring brain in terms of density (Bmax) and affinity (Kd) of dopamine D1-like (D1-Rs) and D2-like receptors (D2-Rs), by saturation binding studies. D1-Rs decreased density in both cortex and striatum (15-30%) by MeHg and PCB153, either alone or combined, without additivity in PND21 males. Changes disappeared by PND36. In females, only MeHg caused a 15% Bmax decrease in striatum. D2-Rs enhanced density (23-50%) and reduced affinity in cortex to a similar extent by all treatments in both weanling and pubertal males. Affinity was also decreased in females by all types of exposure at both ages, while density was enhanced by PCB153 only in a delayed manner (PND36). No changes were detected in striatum. In MeHg and MeHg + PCB153 pup cortex, Hg concentrations ranged, on PND21, between 0.25 and 0.89 and 0.94-1.40 μg/g tissue, respectively, and were 5- to sixfold lower 2 weeks later. PCB153 levels, in PCB153 ± MeHg treated rats, were about 15 μg/g tissue (PND21) and 4-8 μg/g tissue (PND36). In striatum, the Hg and PCB153 concentrations were similar to those in cortex. Brain kinetics trend also applied to blood PCB153 or Hg levels. Perinatal exposure to MeHg and/or PCB153 affects D1- and D2-Rs in a gender-, time-, and brain area-dependent manner. Combined treatment does not exacerbate the neurochemical effects of the individual compounds.
    Archives of Toxicology 02/2011; 85(10):1281-94. · 5.22 Impact Factor
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    ABSTRACT: During a routine truck-tank washing operation, five healthy workers were found motionless inside an empty tanker. Four of them died inside the tanker while the fifth died the following day in hospital. Since the true nature of the fatal compound(s) were not known, a rigorous environmental and toxicological approach supported by autopsy findings was essential to clarify the cause of death. Environmental results indicated that H(2)S fumes arising from the liquid sulfur previously shipped were responsible for the serial deaths, also confirmed by a simulation performed on two similar truck-tanks. These environmental findings were supported by toxicological analyses through the measurement of thiosulfate, one of the main H(2)S metabolites. Abnormal thiosulfate concentrations from 1.1 to 186.2 mg/kg were revealed in all post-mortem biological samples (blood, lung, liver, kidney, brain and fat). Finally, the cluster analysis performed on thiosulfate body distribution contributed to establishing the time of death according to the accident scene reconstruction. This report presents valuable findings in correctly identifying the cause of death in gas asphyxiation cases by unknown compound(s).
    Forensic science international 04/2010; 197(1-3):e19-26. · 2.10 Impact Factor
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    ABSTRACT: This study investigated nucleic acid oxidation associated with exposure to benzene at low levels in 239 workers recruited among traffic policemen, taxi drivers and gasoline pump attendants of the city of Parma (Italy). Biomarkers of exposure, namely urinary t,t-muconic acid (t,t-MA) and S-phenylmercapturic acid (S-PMA), urinary cotinine, and urinary biomarkers of nucleic acid oxidation, namely 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo), 8-oxo-7,8-dihydroguanosine (8-oxoGuo) and 8-oxo-7,8-dihydroguanine (8-oxoGua) were determined by liquid chromatography-tandem mass spectrometry. Relevant polymorphisms of NAD(P)H:quinone oxidoreductase (NQO1), glutathione S-transferases M1-1 (GSTM1), T1-1 (GSTT1), and A1 (GSTA1) were characterized by polymerase chain reaction-based methods in a subgroup of subjects. Biomarkers of nucleic acid oxidation were correlated with each other (r> or =0.32, p<0.0001) and with exposure biomarkers (r> or =0.28, p<0.0001). Multiple linear regression models including age, sex and smoking habits as independent variables demonstrated that benzene exposure is associated with oxidation damage to nucleic acid, particularly to RNA (p<0.0001) and is modulated by the NQO1 polymorphism. The study confirmed a significant modulating effect of GSTM1 (p=0.010), GSTT1 (p=0.023) and GSTA1 (p=0.048) polymorphisms on S-PMA excretion, with a significant interaction between GSTM1 and both GSTT1 and GSTA1 (p=0.006 and p=0.037, respectively).
    Toxicology Letters 04/2010; 193(3):229-35. · 3.15 Impact Factor
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    ABSTRACT: A number of volatile organic compounds (VOCs) have been identified and used in preliminary clinical studies of the early diagnosis of lung cancer. The aim of this study was to evaluate the potential of aldehydes (known biomarkers of oxidative stress) in the diagnosis of patients with non-small cell lung cancer (NSCLC). We used an on-fiber-derivatisation SPME sampling technique coupled with GC/MS analysis to measure straight aldehydes C3-C9 in exhaled breath. Linearity was established over two orders of magnitude (range: 3.3-333.3×10(-12) M); the LOD and LOQ of all the aldehydes were respectively 1×10(-12) M and 3×10(-12) M. Accuracy was within 93% and precision calculated as % RSD was 7.2-15.1%. Aldehyde stability in a Bio-VOC(®) tube stored at +4°C was 10-17 h, but this became >10 days using a specific fiber storage device. Finally, exhaled aldehydes were measured in 38 asymptomatic non-smokers (controls) and 40 NSCLC patients. The levels of all of the aldehydes were increased in the NSCLC patients without any significant effect of smoking habits and little effect of age. The good discriminant power of the aldehyde pattern (90%) was confirmed by multivariate analysis. These results show that straight aldehydes may be promising biomarkers associated with NSCLC, and increase the sensitivity and specificity of previously identified VOC patterns.
    Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 01/2010; 878(27):2643-51. · 2.78 Impact Factor
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    ABSTRACT:   In a public hospital, eight cases of fatal poisoning by nitrous oxide (N2O) occurred under oxygen administration, due to an erroneous swapping of the lines in the gas system. The aim of the study was to clarify the factors involved in asphyxia by characterizing gases from different lines and measuring N2O concentrations in postmortem biological samples from bodies exhumed. Analyses carried out on the gas system confirmed the erroneous substitution of O2 line with N2O and air line with O2. Consequently, high N2O amounts were revealed in several tissues and gaseous biological samples. All specimens were analyzed by headspace gas chromatography technique. A rigorous quantitative analysis was possible only in blood (11.29–2152.04 mg/L) and urine (95.11 mg/L) and in air samples from stomach and trachea (from 5.28 to 83.63 g/m3). This study demonstrates that N2O can be detected in biological samples even 1 month after death.
    Journal of Forensic Sciences 12/2009; 55(1):258 - 264. · 1.24 Impact Factor
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    ABSTRACT: Polybrominated diphenyl ether (PBDE) flame retardants have become widespread environmental contaminants. The highest body burden has been found in toddlers and infants, due to their exposure through breast milk and house dust, and the current concern for potential adverse health effects of PBDEs relates to their developmental neurotoxicity. The mechanisms underlying the neurotoxicity of PBDEs are largely not understood, though there is evidence that PBDEs may elicit oxidative stress. In this study, two different mathematical models were used to evaluate the interaction between BDE-47 and BDE-99 on viability of neuronal cells. The combined exposure to these compounds induced synergistic effects at concentrations of BDE-47 below its threshold doses, and in a wide range of BDE-99 concentrations below its IC(50). In contrast, at concentrations of BDE-47 near its IC(50) value, and in a wide range of BDE-99 concentrations, antagonistic effects were observed. The interactions observed on cell viability were confirmed by an assessment of induction of oxidative stress. The finding that co-exposure to BDE-47 and BDE-99 could induce synergistic neurotoxic effects, in particular at low doses of BDE-47, is of much toxicological interest, as humans are exposed to mixtures of PBDEs, most notably tetra- and penta-BDE congeners.
    Toxicology in Vitro 09/2009; 24(1):116-22. · 2.65 Impact Factor
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    ABSTRACT: The aim of this study was to assess and monitor airway exhalation and deposition of particulate matter (PM). After standardizing inspiratory/expiratory flow and volumes, a novel device was tested on a group of 20 volunteers and in a field study on workers exposed to cristobalite. Both male and female subjects showed a higher percentage of deposition in the 0.5 microm channel than in the 0.3 microm channel on a laser particle counter, but it was higher in the males because of their higher exhaled lung volumes. The device was tested on a wider range of particles (0.3-0.5-1.0-2.5 microm) in the cristobalite productive division. The device has low intrasubject variability and good reproducibility, with geometric mean of %CV < 5%. Such a measure can be used to assess individual susceptibility to PM, making repeated measures in different environments, and examining the persistence of particles in the airways after a period in polluted environments.
    Biomarkers 05/2009; 14(5):326-39. · 1.88 Impact Factor
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    ABSTRACT: A simple and reliable solid phase microextraction/gas chromatography-mass spectrometry (SPME/GC-MS) method was developed for the single-step determination of PCBs 126 and 153 in rat brain and serum, using liquid/liquid and solid phase extraction (SPE) as reference techniques. The multi-factor categorical experimental design used to study simultaneously the main parameters and their interactions affecting the efficiency of the method, showed that the use of an 85mum PA exposed at 100 degrees C for 40min was the optimum sampling condition for both PCBs. SPME was then validated by studying its linear dynamic (over two orders of magnitude), limits of detection (brain: 2ng/g, serum: 0.2ng/g) and analytical precision that was within 9% for SPME in both brain and serum. Finally, the method was used to determine the brain and blood target dose in mothers and pups after oral exposure of the mothers.
    Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 03/2009; 877(8-9):773-83. · 2.78 Impact Factor
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    ABSTRACT: A comparative evaluation of urinary biomarkers was carried out to characterize benzene exposure in a group of 100 traffic policemen of the city of Parma (Italy). All subjects were monitored once, in two consecutive days characterized by similar climatic conditions but preceded by two windy days. Benzene ambient concentration measured by municipal air monitoring stations was 1 microg/m(3) (Day 1) and 2 microg/m3 (Day 2). Personal exposure to ambient concentrations of benzene, toluene, ethylbenzene and xylene (BTEX) was assessed by using Radiello((R)) passive-diffusive samplers in a subgroup of 24 workers. Benzene metabolites, t,t-muconic acid (t,t-MA) and S-phenylmercapturic acid (S-PMA) were determined by isotopic dilution liquid chromatography-tandem mass spectrometry on spot urine samples collected at the end of the shift. Urinary benzene (U-B) was determined by solid-phase microextraction gas chromatography-mass spectrometry. Airborne benzene concentration expressed as median [and interquartile range] was 6.07 [0.28-9.53] microg/m(3), as assessed by personal sampling. Urinary concentrations of biomarkers in the whole group were 41.8 [34.1-89.8] microg/g creatinine for t,t-MA, 0.67 [0.23-1.32] microg/g creatinine for S-PMA, and 0.16 [0.13-0.26] microg/l for U-B. Smokers eliminated significantly higher concentrations of unchanged BTEX and benzene metabolites than non-smokers (p < 0.05). When traffic policemen were distinguished into indoor (n=31) and outdoor workers, no significant differences were observed for either airborne benzene or urinary biomarkers. Significantly lower concentrations of S-PMA and U-B were determined in samples collected at Day 1 as compared to Day 2 (p < 0.0001 and p = 0.003, respectively) suggesting that these biomarkers are enough sensitive and specific to detect changes in airborne benzene concentration even at few microg/m(3).
    Toxicology Letters 09/2008; 181(1):25-30. · 3.15 Impact Factor
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    ABSTRACT: Chromium in exhaled breath condensate (EBC) has recently been proposed as a biomarker of pulmonary exposure. The aim of this study was to measure the Cr levels in the EBC and pulmonary tissue of patients with early, operable non-small cell lung cancer (NSCLC) who had not been occupationally exposed to Cr before and after tumour resection and to correlate Cr in lung tissue with that in EBC. Cr levels in the EBC and pulmonary tissue of 20 NSCLC patients were measured by means of electrothermal atomic absorption before and after tumour resection. Cr levels were also measured in the urine of 15 of these patients. The pre-surgery EBC Cr levels of the NSCLC patients were not different from those of the controls, but both EBC and urinary Cr levels increased after surgery. There was a significant correlation between Cr levels in EBC and pulmonary tissue (R = 0.55, P = 0.01), but not between these and urinary Cr levels. Cr levels in EBC and urine of NSCLC patients were increased after surgical intervention. Measured Cr EBC levels were by one order of magnitude lower than those observed in moderately exposed workers. This fact, together with the correlation between Cr in EBC and in pulmonary tissue, confirms that EBC is a promising biological fluid to test pulmonary exposure to Cr, giving complementary information to that provided by urinary Cr, not correlated with EBC and tissue.
    International Archives of Occupational and Environmental Health 03/2008; 81(4):487-93. · 2.10 Impact Factor
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    ABSTRACT: Me-Hg and PCB153 are known neurotoxic contaminants which tend to accumulate in food, particularly in fish. Aim of this study was to perform asynchronous and combined exposure to Me-Hg and PCB153 in a neuronal rat cell line (PC12) to better characterise the antagonism observed at some combination concentrations. PC12 cells were treated with three concentrations of Me-Hg (0.1-0.5-1.0 microM) and PCB153 at one concentration (175 microM) in single and combined asynchronous exposures, using viability (MTT assay) as end-point. At all concentrations used, a statistically significant antagonistic effect was observed when Me-Hg preceded PCB153 exposure, while effect was additive when PCB153 preceded Me-Hg exposure. The antagonism is particularly evident at low concentrations of Me-Hg (0.1 microM). In conclusion, combined asynchronous exposure showed that whereas Me-Hg can modulate PCB153 toxicity, the opposite seems not to be true. Therefore, the use of asynchronous exposure could be a promising approach to study the mechanisms of toxicity of binary mixtures.
    Food and Chemical Toxicology 03/2008; 46(2):808-11. · 3.01 Impact Factor
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    ABSTRACT: Exhaled breath condensate (EBC) consists mainly of water, but also contains semivolatile and nonvolatile compounds. The aim of this study was to develop a system in which two condensers are simultaneously used in series to clarify the mechanisms of EBC condensation. Two aliquots of EBC (EBC1 and EBC2) were collected from 20 asymptomatic smokers and 20 healthy young nonsmokers using a specifically designed device having two condensers in series in which total volume, hydrogen peroxide (H(2)O(2)), ammonium (NH(4)(+)), and conductivity before and after lyophilization were measured. Water, NH(4)(+) levels and conductivity before lyophilization were significantly lower in the EBC2 than in the EBC1 of smokers and nonsmokers; the contrary was true for H(2)O(2) levels. Almost all nonvolatile salts were collected in the first condenser, because more than 50% of postlyophilization conductivity was below the detection limit in EBC2. The recovery of volatile molecules and their derivatives (water and NH(4)(+)) was partial in the first condenser, but appreciable amounts of both were measured in the second; however, the condenser immediately in contact with exhaled air was more efficient in terms of water, NH(4)(+) and conductivity before lyophilization. On the contrary, nonvolatile ions (conductivity after lyophilization) were mainly collected in the first condenser. Finally, the behavior of H(2)O(2) cannot be explained on the basis of its chemical and physical properties, and the most probable explanation is that some was byproduced by a radical reaction in the gas phase or during the condensation process in water.
    Journal of Aerosol Medicine and Pulmonary Drug Delivery 03/2008; 21(1):35-44. · 2.89 Impact Factor
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    ABSTRACT: Exhaled volatile organic compounds (VOCs), mainly aliphatic and aromatic hydrocarbons, have been proposed as a diagnostic test for early lung cancer detection, but the effect of lung cancer surgical re-moval on exhaled VOCs pattern has never been specifically addressed. The aim of this study was to compare VOC levels measured in non small cell lung cancer (NSCLC) patients before surgery (T0), one month (T1) and 3 years (T2) after surgical removal of tumour. In order to better understand the pathophysiological meaning of exhaled aromatic hydrocarbons, the same exhaled biomarkers were also assessed in cancerous and macroscopically unaffected lung tissue samples collected during surgical operation. Exhaled breath was collected in a specially designed Teflon bulb trapping the last 150 ml of a single slow vital capacity. After solid phase micro-extraction, VOCs were analysed in gas chromatography-mass spectrometry. VOC levels were unaffected by surgical removal, except for isoprene, whose concentration was significantly reduced. Three years after surgical operation, some VOCs significantly changed from baseline: in particular, we noted a decrease in isoprene and benzene concentrations, whereas the levels of pentane, toluene and ethylbenzene were increased in comparison with baseline values. Finally, lung tissue analysis showed that all aromatic hydrocarbons, except xylenes, were significantly higher in cancerous than in unaffected tissue. This study showed that surgical operation can influence the concentration of some exhaled VOCs opening a new scenario in the use of exhaled VOCs in lung cancer patients, not only for diagnostic but also for follow up purposes.
    Acta bio-medica: Atenei Parmensis 02/2008; 79 Suppl 1:64-72.
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    ABSTRACT: Exhaled breath condensate (EBC) consists mainly of water, but also contains semivolatile and nonvolatile compounds. The aim of this study was to develop a system in which two condensers are simultaneously used in series to clarify the mechanisms of EBC condensation. Two aliquots of EBC (EBC1 and EBC2) were collected from 20 asymptomatic smokers and 20 healthy young nonsmokers using a specifically designed device having two condensers in series in which total volume, hydrogen peroxide (H(2)O(2)), ammonium (NH(4)(+)), and conductivity before and after lyophilization were measured. Water, NH(4)(+) levels and conductivity before lyophilization were significantly lower in the EBC2 than in the EBC1 of smokers and nonsmokers; the contrary was true for H(2)O(2) levels. Almost all nonvolatile salts were collected in the first condenser, because more than 50% of postlyophilization conductivity was below the detection limit in EBC2. The recovery of volatile molecules and their derivatives (water and NH(4)(+)) was partial in the first condenser, but appreciable amounts of both were measured in the second; however, the condenser immediately in contact with exhaled air was more efficient in terms of water, NH(4)(+) and conductivity before lyophilization. On the contrary, nonvolatile ions (conductivity after lyophilization) were mainly collected in the first condenser. Finally, the behavior of H(2)O(2) cannot be explained on the basis of its chemical and physical properties, and the most probable explanation is that some was byproduced by a radical reaction in the gas phase or during the condensation process in water.
    Journal of Aerosol Medicine 02/2008; · 1.61 Impact Factor
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    ABSTRACT: Occupational/environmental exposure to some metallic elements is a risk factor for the development of lung diseases, including lung cancer. We aimed at investigating the levels of arsenic, beryllium, cadmium, cobalt, chromium, nickel and lead in the lung tissue of patients affected by early stage non small cell lung cancer (NSCLC). A small number of patients without a diagnosis of lung cancer were also included as control group. Lung tissue biopsies were collected from 45 NSCLC patients (both cancerous and unaffected tissues) and 8 control subjects undergoing surgery. Patients were stratified for smoking habits, histopathology and cancer sites. Metallic elements were determined in dry tissue after digestion by means of ICP-MS. Cd, Ni and Pb levels were higher in unaffected than in control tissues (0.52 vs 0.18 microg/g dry, p < 0.05 for Cd; 4.49 vs 1.8 microg/g dry,p < 0.05 for Ni; 0.21 vs 0.06 microg/g dry, p < 0.01 for Pb). The three elements, and particularly Cd, were influenced by smoking habits; Pb levels were higher in squamocellular carcinoma than adenocarcinomas; Ni distributed in the lungs in an inhomogeneous way. This study demonstrates that the unaffected lung tissue is more representative than the cancerous tissue of the pulmonary content of metallic elements. Tobacco smoke is a main factor affecting the concentration levels of Cd, Pb, and to a lesser extent Ni in the lung tissues of NSCLC patients. The role of past environmental-occupational exposures could not be fully elucidated, due to the limited sample size and the retrospective nature of the study.
    Acta bio-medica: Atenei Parmensis 01/2008; 79 Suppl 1:43-51.
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    ABSTRACT: Epidemiological and laboratory studies have suggested that polychlorinated biphenyls (PCBs) and methyl mercury (MeHg) may have additive or synergistic effects on CNS function. Aim of this study was to characterize the effects of exposure to low levels of MeHg (0.5mg/kgday in drinking water) and PCB126 (100ng/kgday in food), alone and in combination, on neurobehavioral development in Wistar rats. Dams were treated from gestational day 7 to post-natal day (PND) 21. Animals were tested for developmental landmarks and reflexes (PND1-21), attention deficits (PND40), locomotor activity (PND30, 110), spatial learning (PND75), coordination and balance (PND90), object discrimination (PND80), anxiety (PND100), and conditioned learning (PND110). Parameters related to pregnancy, sex ratio at birth, and physical development (at weaning) did not differ among groups, though PCB126 decreased number of pups at birth. A slight delay in negative geotaxis was found in female rats in all treatment groups. No significant effects were seen in attention, coordination and balance, object discrimination, and spatial and conditioned learning. Increased motor activity was present in PCB126-treated male and in MeHg+PCB-treated female rats in the elevated plus maze test, and in PCB126-treated male rats in the open field test (PND110). The results do not support the hypothesis that co-exposure to MeHg and PCB126 results in additive or synergistic effects. This finding is in agreement with more recent in vitro and in vivo studies.
    Environmental Toxicology and Pharmacology 01/2008; 25(1):103-13. · 2.01 Impact Factor
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    ABSTRACT: In the last few decades, combined exposure to methylmercury (MeHg) and polychlorinated biphenyls (PCBs) from fish and seafood, and their potentially interactive effects on neurodevelopment, have been giving increasing cause for concern. We examined the combined effects of MeHg and either a non-dioxin PCB (PCB153) or a dioxin-like PCB (PCB126) congener on the developing brain cholinergic muscarinic receptors (MRs). These receptors are known to play a major role in many central functions including higher cognitive processes and the modulation of extrapyramidal motor activity. MRs in pup rat brains diminished following prenatal and lactational exposure, from gestational day [GD]7 to postnatal day [PND]21, to MeHg (0.5mg/kgbodyweight[bw]/day), PCB153 (5mg/kgbw/day), and PCB126 (100ng/kg/day), alone or in combination. Total MR density, as well as M1, M2, and M3 receptor subtypes of the weanling and pubertal rats, were affected in a brain-area-, gender-, time- and compound-dependent fashion. MeHg decreased (by 15-20%) the total MR density in a delayed (PND36) manner in the cerebral cortex of both genders, and early (at weaning) in the cerebellum of both genders, with the effect lasting until puberty (in males only). MeHg decreased the ACh M1- and M3-immunopositive neurons in the cerebral cortex and also increased the M2-immunopositive Bergmann glia in the cerebellum. PCB153 also induced a delayed (PND36) decrease (of 20%) in total MR number in the cerebellum of the male offspring and in the cerebral cortex of both genders. The latter effect was coupled with a decrease in ACh M1- and ACh M3-immunopositive neuron populations. PCB126 decreased (by 30-40%) total MR density in a gender-dependent manner, males being more sensitive than females. The effect was evident early (at PND21) and lasted until puberty in the cerebellum, while it was observed later (at PND36) in the cerebral cortex. The M1 and M3 receptors were similarly affected by PCB126. Co-exposure to MeHg and either PCB153 or PCB126 had the same effect on the cerebral MRs as exposure to each compound alone. The results rule out additive or synergistic interactions between MeHg and PCB153 or PCB126 on MRs in the brain areas examined. Some early-onset changes persisted until puberty, while other modifications became manifest only at the advanced time point (PND36), when the brain levels of total Hg, PCB153, and PCB126 had declined. These data support the ability of MeHg and PCBs to induce delayed neurotoxicity after developmental exposure.
    Toxicology 09/2007; 238(1):34-48. · 4.02 Impact Factor
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    ABSTRACT: An integrated approach based on ambient and biological monitoring, the latter including both biomarkers of exposure and susceptibility, was applied to characterize benzene exposure in a group of 37 taxi drivers of the city of Parma (Italy). Airborne benzene concentrations were assessed by 24 h personal sampling and work-shift sampling inside the taxicab using passive samplers (Radiello). Benzene metabolites, trans,trans-muconic acid (t,t-MA) and S-phenylmercapturic acid (S-PMA), and urinary cotinine as biomarker of smoking habits were measured by isotopic dilution liquid chromatography tandem mass spectrometry in both pre-shift (PS) and end-of-shift (EOS) samples. Urinary benzene (U-B) levels were determined by solid-phase microextraction gas chromatography-mass spectrometry in EOS samples. Relevant polymorphisms of microsomal epoxide hydrolase, NAD(P)H:quinone oxidoreductase, glutathione S-transferases M1-1 (GSTM1), T1-1, and A1 were characterized by PCR-based methods. Mean airborne benzene concentration was 5.85 +/- 1.65 microg/m3, as assessed by 24 h personal sampling integrating for work-shift, indoor or general environment activities. Significantly, higher benzene concentrations were detected in the taxicab during the work-shift (7.71 +/- 1.95 microg/m3, p < 0.005). Smokers eliminated significantly higher concentrations of U-B and S-PMA than non-smokers in EOS samples [geometric mean (geometric S.D.): 2.58 (4.23) versus 0.44 (1.79) microg/l for U-B; 3.79 (1.50) versus 2.14 (1.87) microg/gcreat. for S-PMA, p < 0.002]. Within smokers, S-PMA concentrations significantly increased at the end of the work-shift compared to pre-shift values (p < 0.05). t,t-MA showed a similar behaviour, although differences were not significant. In the narrow range examined, no correlation was observed between air benzene concentration and urinary biomarkers. All benzene biomarkers but EOS t,t-MA were correlated with U-cotinine (p < 0.05). GSTM1 polymorphism significantly modulated S-PMA excretion, as subjects bearing the GSTM1pos genotype [3.61 (1.15) microg/gcreat.] excreted significantly higher S-PMA concentrations than GSTM1null subjects [2.19 (1.18) microg/gcreat., p < 0.05].
    Toxicology Letters 01/2007; 167(2):142-51. · 3.15 Impact Factor

Publication Stats

571 Citations
94.72 Total Impact Points

Institutions

  • 2008–2012
    • Università degli Studi di Brescia
      • Department of Clinical and Experimental Sciences
      Brescia, Lombardy, Italy
  • 1999–2012
    • Università degli studi di Parma
      • Department of Clinical and Experimental Medicine
      Parma, Emilia-Romagna, Italy
  • 2007–2011
    • Fondazione Salvatore Maugeri IRCCS
      Ticinum, Lombardy, Italy
  • 2002
    • University Hospital of Parma
      Parma, Emilia-Romagna, Italy