1,720,974 research outputs found
Dioxin and PCB contamination of fish and shellfish : assessment of human exposure. Review of the international situation
No full textEsposizione ai tricoteceni dei bambini in età prescolare e scolare
No full textThe occurrence of trichothecene toxins in cereals present in the diet of nursery school babies (age 12-36 months) and primary school children (age 6-10 years) was monitored in Milan. Cereal-based food (bread, pasta, cookies, pizza, etc.) was daily collected and weekly pooled for 5 weeks in May and June 2004, for babies and children, respectively. Cereals were both from organic (nursery and primary schools) and conventional (primary schools) agriculture. The analysis of trichothecenes was performed by gas chromatography-mass spectrometry, and detection limits were 2 μg/kg for Deoxynivalenol (DON) and Nivalenol (NIV) and 10 μg/kg for T-2 and HT-2 toxins.
NIV, T-2 and HT-2 toxins were never found while DON was detected in all samples and the average concentrations were 45 μg/kg for nursery school and 82 μg/kg for primary school samples. The calculated expositions were 0,76 μg/kg b.w./day for babies and 0,89 μg/kg b.w./day for children, and resulted 76 and 89%, respectively, of the UE-SCF TDI (1 μg/kg)
Simultaneous measurement of boldenone (alpha and beta), ADD, testosterone, epitestosterone and AED in bovine faeces
No full textEsposizione all’Ocratossina A dei bambini in età prescolare e scolare
No full textOchratoxin A is a typical cereal contaminant mainly produced by Aspergillus and Penicillium. With the aim to estimate the quantity of ochratoxin A that can be taken in by a child, samples present in the diet of nursery school babies (age 12-36 months) and primary school children (age 6-10 years) were monitored in Milan. Cereal-based food (bread, pasta, pizza, cakes etc.) was daily collected and weekly pooled for 5 weeks in May and June 2004, for babies and children, respectively. Cereals were both from organic (nursery and primary schools) and conventional (primary schools) agriculture. The analysis of ochratoxin A was performed by high-performance liquid chromatography with fluorescence detector, and detection limit was 0,020 μg/kg. Ochratoxin A was found in all samples (100%) and the average concentrations were 0,048 μg/kg for nursery school and 0,161 μg/kg for primary school samples. The calculated expositions were 0,0008 μg/kg b.w./day for babies and 0,0017 μg/kg b.w./day for children, and resulted 16 and 35%, respectively, of the UE-SCF TDI (0,005 μg/kg b.w./day)
Presenza di ocratossina A e tricoteceni in alimenti destinati ai bambini in età prescolare e scolare
No full textHPLC-HRMS methods in horse doping control and forensic veterinary toxicology : a case report about the analysis of anticoagulants
No full textA routine high pressure liquid chromatography-high resolution mass spectrometry (HPLC-HRMS) screening method used for horse doping control in blood and urine was used to identify the likely poisoning of a horse in a 1 ml of gastric, hemorrhagic blood. The veterinarian diagnosis hypothesized the ingestion of a substance belonging to the class of anticoagulants, widely used in agricultural and urban rodent control. Three methodological protocols for the detection of anticoagulant rodenticides in biological tissues were used. As a first step, the screening method of the laboratory, consisting in solid phase extraction (SPE) extraction and HPLC-HRMS analysis, was used: the unknown poison was thus identified as Coumachlor (anticoagulant of the first generation). On the basis of this result, we performed a simple and very fast liquid-liquid extraction followed by ultra high pressure liquid chromatography (UHPLC) HRMS (6 min) analisys for the screening of 8 rodenticides plus embutramide, an active principle of Tanax, a medicine used for euthanasia in veterinary practice. All these substances are of interest in forensic veterinary toxicology. The HRMS analysis was coupled to activated Collision Induced Dissociation (CID) to obtain a further confirmation. The instrument was operated in electrospray ionization, with positive-negative polarity switching mode (1 sec). The resolution was set at 25,000. The final analyses were performed both with a Triple Quadrupole and a Linear Ion Trap mass spectrometer and confirmed the results obtained by HRMS operating in CID mode, so demonstrating the fitness of the method also for confirmation analyses. The limit of detection (LOD) and limit of quantification (LOQ) were calculated for all the analytes. Operating in CID-HRMS, classic doping substances like Methylprednisolone, Bumethanide, was detected and confirmed. The UHPLC-HRMS analisys was also tested on blood from an horse in treatment, for navicular syndrome, with warfarin
In vitro transformation of boldenone and related steroids in veal faeces : preliminary results
No full textStudi preliminari di stabilità in vitro di boldenone (ALFA e BETA), testosterone ed epitestosterone glucuronati in feci bovine
No full textThe stability of and Boldenone glucuronides (BOLg), Testosterone glucuronide (Tg) and Epitestosterone glucuronide (ETg) in bovine faeces was studied in vitro. The detection of the glucuronide steroids, added to saline sospensions of faeces, and of the respective free forms, was performed by HPLC-MS/MS in positive APCI mode. The results show that Tg and BOLg, as previously observed for the free forms, resulted poorly stable; α Bolg and ETg transformed mainly into α Boldenone (α Bol) and Epitestosterone (ET). Neo formations of α Bol and ET were also confirmed
Investigation on possible transformations of cortisol, cortisone and cortisol glucuronide in bovine faecal matter using liquid chromatography-mass spectrometry
No full textGiven the close resemblance of the ring A structure of prednisolone and prednisone on the one hand,and of androstadienedione on the other, the transformation of cortisol and cortisone into prednisolone and prednisone in cattle faeces was evaluated. A simple method that does not involve extraction but only the 1:100 dilution of cattle faeces, spiking with 400 ng/mL cortisol, cortisone or cortisol glucuronide
and incubation of the suspension, was used. The analyses were performed by HPLC–MS3 to detect the supposed Delta1 dehydrogenation of the glucocorticoids. The decision limits (CCalfa) and detection capabilities
(CCbeta) were 2.0 and 3.0 ng/mL for cortisol, cortisone and prednisolone, 3.0 and 4.0 ng/mL for cortisol glucuronide and 7.0 and 10.0 ng/mL for prednisone, respectively. Intra-day and inter-day coefficients of variation (CV%), were 5.6–6.2 and 5.2–6.6 for cortisol glucuronide, cortisol, cortisone and prednisolone,
and 16.0 and 16.2 for prednisone, respectively. The recoveries were in the range 110–143% for all analytes.
Regression coefficients (R2) were in the range 0.996–0.999 for all analytes. The resultsshowthe hydrolysis of the conjugated form and the dehydrogenation in ring A in diluted faeces. It is therefore predicted that urine contaminated with faeces may be positive for prednisone and prednisolone in the same way as they are positive for boldenone, i.e. as a result of microbiological dehydrogenase activity on cortisol and cortisone
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