Biomedical subjects

L Perbellini

Publications and source records attributed to L Perbellini.

114 records · Page 7Linked to original sources

PubMedDate not supplied

Carbon disulfide in blood: a method for storing and analysing samples.

Concentrations of free and acid-labile carbon disulfide in human blood were determined by gas chromatography mass-spectrometry. Carbon disulfide was measured in the blood of 62 subjects not occupationally exposed to the solvent, and in 27 subjects treated with disulfiram (which is partially biotransformed into carbon disulfide). In blood, a small part of carbon disulfide is free (it can be analysed without any blood treatment); most carbon disulfide is bound ("acid labile" carbon disulfide), and requires acid hydrolysis to become free and detectable. During the first phase of our study, stored samples of blood (storage at 4 degrees C for 15-40 days) were used. Later, we analysed fresh blood samples. A significant decrease in carbon disulfide was found in stored samples in comparison to fresh samples. During storage, free and acid-labile carbon disulfide in blood decreased respectively to 26% and 27% of the initial concentration within a month. In fresh samples, free carbon disulfide concentrations in blood showed a median of 139 ng/l in normal subjects. Acid-labile carbon disulfide concentrations were much higher (median 2743 ng/l). Free and acid-labile carbon disulfide in blood were closely correlated (r = 0.9358). Blood samples stored at -80 degrees C maintained a constant concentration of carbon disulfide over almost three weeks.

Alcoholism↗

PubMedDate not supplied

[Blood interface in environmental and occupational exposure to industrial chemical pollutants].

The concentration of 12 environmental chemical pollutants was measured in the blood of the general population. With reference to the 12 different pollutants, the blood samples tested varied from 88 for acetone to 431 for benzene. Nine of these agents (benzene, toluene, styrene, cumene, xilene, n-hexane, nitrous oxide (N20), acetone and carbon disulphide) were present in all or almost all (100-94%) blood samples. The three chlorides (chloroform, trichloroethylene and tetrachloroethylene) were present only in 60-85% of samples. After acetone and carbon disulphide, with blood concentrations in microgram/l (mean 840 micrograms/l and 2.4 micrograms/l respectively), the highest mean blood levels were those of toluene (1097 ng/l), chloroform (955 ng/l), N2O (915 ng/l), and n-hexane (642 ng/l). Trichloroethylene and free carbon disulphide had similar values (458 and 438 ng/l, respectively). Finally, benzene, styrene and tetrachloroethylene had the lowest values (262, 217 and 149 ng/l, respectively). There was generally a significant difference between rural and urban workers in terms of blood benzene (200 ng/l vs. 264 ng/l), trichloroethylene (180 ng/l vs 763 ng/l) and tetrachloroethylene (62 ng/l vs. 263 ng/l). In a group of subjects potentially exposed to industrial solvents, classed as chemical workers, blood benzene, toluene, chloroform and n-hexane were significantly higher than in rural and urban workers. Smokers showed a significantly higher blood concentration than non-smokers for benzene (381 ng/l vs. 205 ng/l), toluene (1431 ng/l vs. 976 ng/l) and n-hexane (803 ng/l vs. 505 ng/l).

Acetone↗

PubMedDate not supplied

[Environmental exposure and blood levels of benzene in gas station attendants. Comparison with the general population].

Environmental benzene levels were measured in 26 petrol stations using both active and passive stationary and personal samplers. Simultaneously, benzene levels were measured in the petrol station operators on blood samples collected at the end of the work shift and the following morning before starting work. The petrol stations belonged to various different oil companies and were studied both during the winter (9 stations) and in the summer (17 stations). The environmental levels measured with active samplers in the 26 stations were on average 256 ng/l, were significantly lower (98 ng/l) in winter and higher (326 ng/l) in summer. The blood levels of benzene in 77 workers at the end of the work shift were on average 548 ng/l, were significantly lower (306 ng/l) in winter and higher (651 ng/l) in summer. The following morning, blood levels of benzene were lower than those found at the end of the work shift, on average 249 ng/l in winter and 427 ng/l in summer. Smokers had higher benzene levels than non-smokers, both in winter at the end of the work shift (617/170 ng/l) and the following morning (506/137 ng/l), and in summer at the end of the shift (742/517 ng/l) and the following morning (535/233 ng/l). A comparison with a sample of 243 "normal" subjects of the general population showed that their mean blood level of benzene of 165 ng/l was significantly lower than the level found in petrol station workers the morning after the work shift (364 ng/l).

Adolescent↗

PubMedDate not supplied

Biological monitoring of acrylonitrile exposure.

This study reports the results obtained with the environmental and biological monitoring of 34 workers exposed to acrylonitrile (ACN). Occupational exposure was monitored during 8-h work shifts with both active and diffusive personal samplers which yielded comparable results. The median exposure was 78 micrograms/m3. The ACN concentration in urine collected at the end of the work shifts correlated significantly with the environmental exposure. The ACN concentration in the pre-shift urine samples (median 3.6 micrograms/l) was lower than that found in the post-shift samples (median 10.9 micrograms/l), but higher than in the urine of non-exposed people (median 0.45 microgram/l). Smoking is an important confounding factor in monitoring exposure to ACN. The ACN concentration in urine provides reliable information about occupational and non-occupational exposure to ACN. Aspects of the mechanism of ACN excretion in urine are also discussed.

Acrylonitrile↗

PubMedDate not supplied

[Chrono-thermometry in the diagnosis of Raynaud-like vasculopathies caused by prolonged use of vibrating tools].

Raynaud's phenomenon may be secondary to several different pathological conditions. In some cases it is favoured by occupational exposure to vibration of the upper arms. The diagnosis of Raynaud's phenomenon requires clinical information together with specific technical investigations. This report presents the results of 232 chrono-thermometric tests performed on 157 workers exposed to vibrations during the use of different kinds of tools. Seventy-five subjects not exposed to vibrations of the upper arms but with suspected Raynaud's syndrome were also tested. Chrono-thermometry enabled us to distinguish between three different subgroups of subjects exposed to vibrations: 61 workers with "normal" chrono-thermometry, 33 subjects with "pathological" vascular reactivity to cold in some fingers and 63 workers with such reactivity in all fingers. Similarly the 75 patients not exposed to vibration could also be divided into three groups. No statistical difference was found between the chrono-thermometric results obtained from the exposed and non-exposed subjects when divided into the three subgroups. The overall analysis of the combined results of the different kinds of tests (capillaroscopy plus a vascular reactivity test) is discussed.

Adolescent↗

PubMedDate not supplied

[The determination of urinary cyclophosphamide at low concentration levels by liquid-liquid extraction and HPLC/MS/MS analysis].

A sensitive, specific and accurate high-performance liquid chromatography-ion spray-tandem mass spectrometry procedure (HPLC/MS/MS) has been developed to quantify cyclophosphamide in human urine. This methodology, which includes the liquid-liquid extraction with ethyl acetate, requires no derivatization procedures, preventing cyclophosphamide from possible thermal and chemical decomposition reactions. This methodology was validated by the use of ifosfamide as internal standard (I.S.). The assay was linear over the range 0 to 3.2 ng mL-1 urine, having a low limit of quantification of 0.2 ng mL-1. The low limit of detection was assessed at 0.05 ng mL-1 urine. This method is characterized by a coefficient of variation < 10%. Standard calibration curves, performed on three different days, had correlation coefficient always greater than 0.998. The intra and inter-day precision were within 11%, and accuracy was included in the range 99-103%. The mean extracted recovery assessed at three different concentrations (0.5, 0.8, 3.2 ng mL-1) was always more than 85%. The extraction efficiency of cyclophosphamide from urine samples was also studied at six different pH values (pH 4, 5, 6, 7, 8, 10). CP gave the maximum extraction efficiency when pH urine solutions was adjusted to 7.0 and somewhat lower at the other considered values.

Antineoplastic Agents, Alkylating↗