Urinary excretion of ethylenethiourea in five volunteers on a controlled diet (multicentric study).

Urinary excretion of ethylenethiourea (ETU) was monitored for 8 days in a group of five male non-smoker volunteers on a diet, the items of which were assayed for ETU and carbon sulphide. Urinary excretion of ETU reflected the consumption of wine, fruit and vegetables. Urinary ETU concentrations ranged from 0.6 to 6.7 micrograms/g creatinine. ETU concentrations in the food eaten by the volunteers were generally below the detection limit whereas in wine 8.8 micrograms/l ETU was detected. Evolution of carbon sulphide by food samples ranged from 0.03 to 0.17 mg/kg. Mean (+/- S.D.) daily intake of ETU in wine was 3.5 +/- 0.2% of the acceptable daily intake (ADI): 0.070 +/- 0.004 micrograms/kg body wt. During the 8 days of the study, an average of 48.3% of the ETU ingested in wine was excreted unmodified by the kidneys. Twenty-four hour urinary excretion of ETU was significantly correlated with daily intake of ETU (r = 0.768) and CS2 evolved by the daily food items (r = 0.414).

Reference values of urinary ethylenethiourea in four regions of Italy (multicentric study).

The results of a study in which urinary ethylenethiourea (ETU) was assayed in the general population (167 subjects) of four Regions of Italy (Veneto, Lombardy, Piedmont and Trentino Alto Adige) are reported. The results are compared with those in a population of 97 subjects from Rovescala, a hillside wine-producing town a few kilometers from Pavia, where ethylenebisdithiocarbamates are sprayed by helicopter. It was found that an average of 24% of the populations of the four regions, taken together, had urinary ETU levels above detection limits (1.0 microgram 1(-1)) as compared to 37% of the population of Rovescala. The ranges of concentration were 0.8-8.3 micrograms 1(-1) for the four regions and 0.9-61.4 micrograms 1(-1) for Rovescala. Statistically significant variables for urinary ETU levels were smoking and wine drinking.

Reference values of urinary 3,5,6-trichloro-2-pyridinol in the Italian population--validation of analytical method and preliminary results (multicentric study).

The interlaboratory validation of analytical procedures for the assay of urinary 3,5,6-trichloro-2-pyridinol (TCP) in the general Italian population is reported. The determinations were performed by high-resolution gas chromatography (HRGS) with electron capture detection and HRGS with mass spectrometry (MS) in 2 laboratories. The urine samples were from 42 participants from 3 regions of Italy. The results were evaluated by interlaboratory quality control. Urinary TCP concentrations were above the detection limit (1.2 micrograms/L) in 88% of the population, with a mean detectable concentration [GM (GSD)] of 2.8 (1.9) micrograms/g creatinine (creat). (GM, geometric mean; GSD, geometric standard deviation.) The Mann-Whitney U test showed that wine consumption was a statistically significant variable (p < 0.05) for urinary concentrations of TCP. Analysis of variance of the logarithm of urinary TCP versus wine consumption and diet showed a statistically significant fit. The model used explained 30% of the total variance: wine consumption and diet accounted for 37 and 17% respectively of the explained variance.

Determination of anabolic steroid 19-nor-testosterone in bovine serum by GC-SIM-MS.

Anabolic steroids extracted from bovine serum by means of organic solvents or solid-phase extraction techniques with C18 cartridges are not suitable for quantitative analysis by gas chromatography-mass spectrometry (GC-MS); therefore, they were extracted from serum by Extrelut columns (Merck; Germany), eluted with diethyl ether, and purified by a solid-phase extraction technique using amino (NH2) columns. The resulting clean extract was treated with heptafluorobutyric anhydride (HFBA); this formed a derivative suitable for GC-MS analysis. Using selected ion monitoring (SIM), quantities as small as 40 pg/mL can be detected.

Monitoring propofol serum levels by rapid and sensitive reversed-phase high-performance liquid chromatography during prolonged sedation in ICU patients.

A quick and sensitive reversed-phase high-performance liquid chromatography (HPLC) method has been developed in order to determine the concentration of Propofol (2,6 diisopropylphenol) in human serum. Propofol can be isolated from serum by adding 0.5 mL precipitating solution. This consists of an acetonitrile and perchloric acid (67:33, v/v) mixture, which also contains dibutylphthalate (2 mg/100 mL) as internal standard. The sample is then mixed for 1 min on a vortex-mixer. The endogenous serum substances precipitated by acetonitrile and perchloric acid are further separated by centrifugation. The supernatant is directly injected into the HPLC system. A 250- x 4.6-mm column, packed with 10-microns Spherisorb reversed-phase octadecylsilane particles (C18), is used for chromatographic separation. The mobile phase consists of an acetonitrile-water mixture (67:33 ratio) with 0.4 mL acetic acid (pH 4). Propofol is monitored by a UV-visible detector at 270 nm and 0.1-0.002 absorbance units full scale (AUFS). The detection limit of Propofol (in human serum) is 0.1 mg/L for a 20-microL injection volume. The time of the assay is less than 20 min, including sample preparation.

[Control of occupational exposure to benzene in a chemical plant]. / Controllo dell'esposizione professionale a benzene in un impianto chimico di sintesi.

Later on detection of several cases of acute myelotoxic intoxications the use of benzene as a solvent has been banned in Italy since 1963 (Law n. 245). Its consumption has therefore been confined to synthesys processes in petrolchemical industry. The hazards arising from the operations performed in an open air chemical plant which produces alkylbenzene were monitored by the AA. The synthesis occurs in a closed system which provides opportunities for benzene exposure during filling, control and maintenance operations. Nine environmental samples out of 10 showed benzene concentrations above 10 ppm with peaks up to 110 ppm. Long term air sampling showed values ranging from 12 to 75 ppm. Urinary phenol elimination has been measured showing values above 50 mg/1 for approximately 20% of workmen. The difficulties pertaining to an adequate control of benzene exposure in chemical plants are discussed. Being skin contact a mode of entry of apreciable concern, the AA. stress out that priority in exposure monitoring should be given to biological tests such as urinary phenol level and benzene concentration in expired air measurements.

[Aromatic amines with certain, probable, or possible carcinogenic action: reference values]. / Ammine aromatiche ad azione cancerogena certa, probabile o possibile: valori di riferimento.

The aim of this work is to determine the amount of some aromatic amines in urine of non-exposed people in order to define a reference value. The literature examination has showed that only a small numbers of aromatic amines are usually determined in urine namely: aniline, benzidine, 2-naphtilamine, o-toluidine, 3,3'-dichlorobenzidine, 4-chloro-o-toluidine and 4-chlorobenzidine. On the basis of our experience the analytical method proposed by Lichtenstein is appropriate for obtaining reliable analytical results.

[Polychlorobiphenyls: reference values]. / Policlorobifenili: valori di riferimento.

The purpose of this work is to compare the PCB values in blood, serum and adipose tissue of non-exposed people over the last twenty years of scientific literature in order to establish whether the determination of single congeners is better then the evaluation of the total PCB amount moreover an analytical strategy useful to define a reference value for non-exposed Italian population has been evaluated. In the literature very variable results were found for the determination of total PCBs in blood, in serum or adipose tissue. We suggest to determine only the amount of the most toxic congeners of PCBs (28, 52, 77, 101, 118, 126, 138, 153, 169, 180) by using the HRGC/ECD as analytical technique.

[New biomarkers of exposure]. / Nuovi indicatori di esposizione.

In this paper we have defined the new biomarkers of exposure (NBE) as those biomarkers discovered in the last five years and, among previously validated biomarkers, also those applied in different ranges of doses or those determined in biological matrices which differ from matrices originally considered. We examined the results from the surveys carried out by the main Italian research units involved in biological monitoring, i.e. those from the Universities of Brescia, Milan, Naples, Padua, Parma, Pavia, Turin and Verona. The data were collected using a standardized model and included the following: type of element or organic compound, type of biomarker, analytical technique and method, their relationship with environmental monitoring data, their relationship with effect indicators or effects in general, improvement with respect to old biomarkers, reference values. Twenty two NBEs were identified: 14 elements and chemical compounds as such or as metabolites, 4 examples of mixtures, 3 of new matrices, one of speciation. Among the others, aspects such as interest in requiring NBE, quality assurance, availability, cost-benefit ratio were discussed. We conclude that development of this specific field of research appears to be a crucial point for future improvement in risk assessment and health surveillance procedures.

Application of semipermeable membrane device (SPMD) to assess air genotoxicity in an occupational environment.

Semipermeable membrane device (SPMD) is a passive sampler that sequesters lipophilic contaminants, mimicking the bioconcentration in the fatty tissue of organisms. This study was designed to assess the use of SPMD and biological tests (Comet assay and Ames test) for air monitoring. For this purpose an occupational environment with expected polycyclic aromatic hydrocarbons (PAHs) contamination (coke plant) was selected for a case study. The SPMDs were deployed in five occupational contaminated sites and in a control site. The SPMD dialysates were chemically analysed and examined for in vitro DNA-damaging activity in human cells (Jurkat) by Comet assay and for mutagenicity with the Ames test (TA98 strain, w/o S9). Total suspended particulates were also collected and analysed (GC-MS). No biological effect of SPMD extract was revealed in the control site. On the other hand, air samples collected with SPMDs within the coke plant showed variable degrees of genotoxic and mutagenic activity. The highest effects were associated with the highest PAH level recovered in the SPMDs extracts and in particulate samples. Results obtained support the sensitivity of biological tests associated to SPMD sampling for evaluating the health risk of potentially contaminated work environments highlighting the usefulness of SPMDs for environmental air quality monitoring.

Clinical, histological, and chemical characterization of ectopic calcification in dialyzed and non-dialyzed patients.

In a review of 11 cases of ectopic calcification (5 of which in dialyzed patients and one in a paraplegic), the authors attempt to characterize this disorder in all its various forms using histological, clinical, and chemical methods. In dialyzed patients, two contributing factors were identified: hyperphosphatemia (plus hypercalcemia) and secondary hyperparathyroidism. In hyperphosphatemic patients the calcifications are multiple, paraarticular, labile, and have a fluid-viscous consistency. In secondary hyperparathyroidism, in addition to the above metastatic calcification there is dystrophic calcification typically localized in the anterior muscles of the hip and thigh. The ectopic calcification of the non-dialyzed patients is true ossification. The precise moment of the onset of the lesion is not always discernable, but its evolution points to primary or secondary local irritation as the trigger. Ossification is the predominant phenomenon in the paraplegic as well, while the triggering mechanism is still unknown.

Heracleum mantegazzianum growth phases and furocoumarin content.

The observation of photocontact dermatitis from Heracleum mantegazzianum Sommier et Levier in 2 gardeners at work prompted the analysis of furocoumarin content of stem, leaves and fruits of the plant during a period of 1 year. Their concentration was found to be maximal in fruit, intermediate in leaf, and minimal in stem. Psoralen was the most prevalent substance in the leaf and bergapten in the fruit. In the stem, in contrast, individual furocoumarins were found in lower but variable concentrations. 3 furocoumarin seasonal peaks were observed in the leaf: the maximal peak occurred in June, the intermediate in August, the minimal in November. This trend corresponds to 3 biological phases of the weed.