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Biomedical subjects

A Colombi

Publications and source records attributed to A Colombi.

At least 109 records · Page 6Linked to original sources
PubMedDate not supplied

Toxicological and immune findings in workers exposed to pentachlorophenol (PCP).

Pentachlorophenol (PCP) is a pesticide used worldwide in industrial and domestic applications. Data available on the effects of technical-grade PCP on the immune system are insufficient and equivocal; some data indicate inhibitory effects, whereas others suggest stimulating effects. This study was performed to evaluate toxicological and immune findings in 32 subjects who had prolonged exposure to PCP in a wood factory and in 37 controls. PCP concentrations were determined in plasma and urine of all subjects. Lymphocyte subsets of CD3-, CD4-, and CD8-positive cells were evaluated, and the proliferative response of peripheral blood mononuclear cells (PBM) to mitogens was assessed. The results suggested the absence of major laboratory and clinical signs of PCP-dependent immune deficiency. A weak effect of long-term exposure to PCP on the functional immune response could not be ruled out because of the finding of a decreased response to 5% PHA in the high-exposure group. A weak effect against hepatocyte membrane was evidenced by the finding of raised serum concentration of glycocholic, taurodeoxycholic, and glycochenodeoxycholic acids in subjects directly exposed to PCP for more than 10 y.

Adolescent↗
PubMedDate not supplied

[Measurements and environmental and biological monitoring of occupational exposure to inhalation anesthetics].

This paper reports the data of nitrous oxide (N2O) environmental pollution in 269 operating rooms of 47 hospitals in Italy in 1989-91. In 40% of the operating rooms the N2O concentrations are lower than 50 ppm, limit value proposed by Health Council for new operating rooms. In 65.4% of the operating room studied, N2O mean environmental concentrations are lower than 100 ppm, value proposed by the above-mentioned Health Council as limit value for the already existing operating rooms. Concerning the biological monitoring, the authors report several N2O data in urine (2193), whose levels confirm the data obtained with environmental monitoring. The authors believe that they presently have reliable methods to perform biological and environmental monitoring: the two techniques are complementary in the assessment of the exposure. The method of measuring N2O concentrations as exposure index, both for the environmental and biological monitoring, is considered very useful to simplify the performance of the analyses. In order to assess exposure more precisely, it is however necessary also to determine the environmental and/or biological measure of the other different anaesthetics used.

Air Pollutants, Occupational↗
PubMedDate not supplied

[Health risks for waste disposal industry workers].

Waste disposal currently constitutes a major public health problem in Italy and other industrialized countries. In view of the increasing volume of waste accumulated and disposed of without control, there is now an ever pressing need for regulated disposal that involves minimum risk for the environment and the community. Hence a new industrial sector has emerged that is highly specialized and varied, on account of the wide field of activity and technology, from collection and storage of refuse, processing and definitive disposal, to reclamation and improvement of illegal dumps. The industrial waste sector has not been fully developed and it is currently believed that most disposal is performed without sanitary control. Little attention has been given to the environmental impact of these operations and similarly little is known of the possible health effects for the operators. Acquisition of toxicological and health data is therefore essential to establish correct and appropriate regulations for the development of this industrial sector. An objective risk evaluation will require filling in many information gaps, which are partly the results of a natural uncertainty surrounding any innovative process, but are above all due to the vastness of the problem that is not easily defined in concrete terms as regards types of waste and number of operators involved.

Humans↗
PubMedDate not supplied

[Acute exposure to vanadium-containing dusts: the health effects and biological monitoring in a group of workers employed in boiler maintenance].

The authors describe an episode of acute intoxication due to inhalation of vanadium-containing dusts in a group of 10 workers during maintenance work inside a boiler of an oil-fired electricity power station. Historical, clinical and biological monitoring data concerning the acute exposure phase and subsequent checks are presented. The appearance of irritative symptoms of the upper airways, green tongue (in 6 out of 10 subjects) and the values of urinary excretion of vanadium (means = 92, D.S. = 47 micrograms/l: limits 20-270 micrograms/l) indicated acute vanadium exposure. With the use of appropriate individual protection devices and shorter shifts, 2 weeks after the episode there was a complete remission of the symptoms and a return of urinary vanadium concentrations to 38, D.S. = 26 micrograms/l. Checks made 6 months, 1 and 2 years later did not reveal any alterations in the general blood chemistry parameters and the urinary vanadium concentrations were below 1 microgram/l (reference value). As already often reported in the literature, this episode confirms the danger involved in working in the presence of fuel oil residues or ashes and the need to adopt appropriate prevention measures.

Acute Disease↗
PubMedDate not supplied

[An integrated course in occupational medicine. A proposed teaching program based on the new organization of the degree course in medicine and surgery].

The curriculum of Italian Medical School of the Faculty of Medicine has been recently renewed at a national level. Considering the numerous innovations introduced, a new role has been attributed to the teaching of occupational health, particularly occupational medicine. Occupational Medicine is usually regarded as a part of community medicine and, despite the fact that occupational disease may be in decline in industrially developed countries, the increasing concern regarding environmental pollution related health effects, stress the relevance of the methodologies already formulated within the occupational health disciplines. Of all environmental factors, occupational medicine has contributed largely to the knowledge about the health effects of occupation and its role in the complex problem at work related to today's medical students as a way of introducing the appreciation of worldwide environmental effects and how to measure, monitor and modify them. In this article the content of the occupational health course is revised and according to the principles of modern medical pedagogy, the teaching is divided in primary and secondary objectives and organized to the resolution of real problems. The importance of the relevant evidences of clinical occupational medicine is discussed and their insertion into other clinical disciplines is proposed. The knowledge of distribution, recognition, management and prevention of the major occupational diseases is a final target of the teaching. The introduction of innovative teaching methods such as factory visits, case history discussion or role playing exercises is suggested as an integrated, multidisciplinary approach able to promote the preventive attitude of students. The efficacy of the teaching has to be evaluated with appropriate methods every time, to verify both informative and formative aspects.

Curriculum↗
PubMedDate not supplied

[Determination of blood bile acids using high pressure liquid chromatography: comparison of chromatographic, enzymatic and immunoenzymatic methods].

A method has been developed for measuring serum conjugated bile acids by HPLC. Serum samples, to which the internal standard is added, are purified by a solid phase procedure and injected on a reverse phase C18 column. Elution is accomplished by means of a flow gradient and peaks are detected at 198 nm. The detection limit ranges between 0.05 and 0.20 mumol/l for different analytes; between-day precision (CV 5.8%), working linear range (up to 50 mumol/l) and recovery (87%) were established. Comparison of the results obtained with HPLC, enzymatic and immuno-enzymatic methods gave high correlation coefficients. The method was applied for diagnostic purpose to a group of subjects suffering from various liver diseases. Also, 106 healthy workers, not occupationally exposed to known or potentially hepatotoxic agents, were studied in order to establish reference values for use in biological monitoring of chronic low level exposure to solvents. The method has the advantage of a more simple procedure compared to previously reported HPLC methods and appears to be well suited for routine use in toxicological and clinical test laboratories.

Adult↗
PubMedDate not supplied

[Biological limits of exposure: evolution of interpretative and methodologic criteria].

Biological monitoring is an extremely efficient investigation tool in evaluation of exposure to exogenous substances, in both occupational and environmental settings. However, although biological tests have been widely acclaimed as the ideal approach to or as a completion of environmental measurements, they have had difficulty in becoming firmly established due to a number of limitations of various nature. Besides the numerous uncertainties in the set-up phase, which depend on the choice of indicators or criteria for their use, difficulties are still incurred in making a univocal interpretation of the results. These difficulties are due to the limited pharmaco-kinetic information available on the various substances and to the wide variability in individual biological response. The possibility of extrapolating Biological Exposure Limits (BELs) from the corresponding TLV-TWA, by means of calculations based on the experimental regressions observed between internal and external dose indices, has up to now been considered a dubious operation from a formal point of view and merely indicative for practical purposes. This paper examines the possibility of establishing BELs that are fixed taking account of the influence of the various biological variables, thus permitting a more correct, objective and generalised use of biological indicators in current practice. From the regression function and relative tolerance limits, intended as a range of values within which regression values can be expected to be found with a probability that can be fixed a priori, it is possible to calculate 3 BEL values for each environmental TLV-TWA concentration. The question of which of these different values should be selected as a BEL for practical purposes must be solved on the basis of a series of observations related to the type of investigation being performed and the context in which the results are to be used. It should be emphasized that each BEL value has its own particular sensitivity and specificity, i.e., the possibility of correctly classifying the exposure conditions in relation to the environmental values. If sensitivity and specificity values are known, it is possible to calculate the predictive value of the biological measurements compared to the environmental measurements; if numerical data on these parameters are available, account can be taken of the variability of the results in a rigourously scientific manner.(ABSTRACT TRUNCATED AT 400 WORDS)

Air Pollutants, Occupational↗
PubMedDate not supplied

[Biological monitoring of occupational exposure to airborne pollutants].

Biological monitoring of inert substances requires knowledge of the mechanisms regulating respiratory absorption. The authors examine the influence of parameters such as work load, exposure duration and biotransformation on the respiratory absorption of inert airborne pollutants in the workplace. Attention is also given to the possibility of using biological thresholds or Biological Equivalent Limits (BELs).

Air Pollutants, Occupational↗
PubMedDate not supplied

[Application of high-pressure liquid chromatography in the analysis of urinary metabolites of aromatic solvents].

The introduction of HPLC methods in industrial toxicology represents a valuable tool for the routine monitoring of workers occupationally exposed to aromatic solvents. The HPLC method described here permits the simultaneous determination of metabolites of ethylbenzene, styrene, toluene, xylene isomers, benzene, phenol and cresol isomers in diluted urine samples. Pretreatment of urine samples with steam distillation is necessary only for determination of phenol and cresols because of their low concentrations. A comparison between a GLC and the HPLC procedure for mandelic and phenylglyoxylic acids confirmed the satisfactory performance of the HPLC method.

Adult↗