Biomedical subjects

S Fustinoni

Publications and source records attributed to S Fustinoni.

24 records · Page 2Linked to original sources

PubMedDate not supplied

[New biomarkers of exposure].

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.

Animals↗

PubMedDate not supplied

[Biologically effective dose biomarkers].

Biologically effective dose markers--DNA and protein adducts--are classified among exposure biomarkers, and are currently used to assess the biologically active fraction of xenobiotics, which is capable of interacting with cellular macromolecules at the target site. Macromolecular adducts should not only be considered as exposure indicators; indeed, their biological significance can also be extended to biomarkers of effect and of susceptibility. The achievement of such a goal needs research programs aimed both at studying molecular mechanisms related to each step along the continuum of events between exposure and disease, and at establishing quantitative relationships between exposure levels and adduct formation, between adducts and early biological effects, effects and cellular structural/functional modifications, leading to the development and eventual increase in incidence of specific diseases. Moreover, different factors must be considered during data evaluation, such as interindividual variability, the background levels of biomarkers in non occupationally exposed population, the gradually decreasing doses of genotoxic agents involved in occupational exposure, and confounding factors such as diet and smoking habits. Despite the large body of literature documenting DNA and protein adduct molecular dosimetry for many carcinogen exposures, many authors highlight the need for systematic interlaboratory comparison and collaboration by measuring the same biomarkers using different techniques and/or different biomarkers related to the same exposure levels. There is also general agreement about reducing costs, so that dosimetric analyses can become economically more advantageous and accessible in all cases where they prove to be useful in preventing health risks.

Biomarkers↗

PubMedDate not supplied

[Assessment of exposure to organic aromatic compounds and PAH in asphalt industry: the PPTP-POPA Study results].

Asphalt is a mixture of mineral matter and bitumen, its fumes contain about 1% of Polycyclic Aromatic Hydrocarbons (PAH), some of which are carcinogens. In the PPTP-POPA Study of Lombardy Region, a group of 100 asphalt workers (exposed to bitumen fumes and diesel exhausts) and a group of 47 ground construction operators (exposed only to diesel exhausts) were investigated to assess PAH exposure in Italy, by means of environmental-air monitoring (the 16 most relevant, according to the American Environmental Protection Agency, EPA) and biological monitoring (urinary 1-hydroxypyrene excretion). Our results show that PAH exposure in these workers is not higher than that observed in traffic policemen working in urban areas. Since dermal exposure has been suggested as a major determinant of the total PAH dose absorbed by road pavers from bitumen fumes, we assessed skin contamination by organic aromatic compounds and by sixteen PAH: in both groups, six pads were applied to each subject in different parts of the body, during the workshift. The results show that the dermal contamination in road pavers is higher than in ground construction operators and that cutaneous dose rate is higher than respiratory dose rate, whereas the amount of absorption the ratio is inverted.

Adult↗

PubMedDate not supplied

[Urinary MTBE as biological marker of exposure to traffic exhaust fumes].

Methyl tert-butyl ether (MTBE) is an oxygenated compound added to Italian fuel in quantity of about 3% v/v. In the present study the excretion of urinary MTBE (U-MTBE) was evaluated as biomarker of exposure to traffic exhaust fumes. With this aim 127 Milan urban policemen, working as traffic wardens, were investigated. Spot urine samples were obtained prior to and at the end of the work shift, in different seasons. Median U-MTBE varied from 74 to 164 ng/L (range 60-657 ng/L). Comparing the pre-shift and end-shift samples an increase of about 14% in the U-MTBE level during the workshift was observed. An influence of the different seasons was observed, with lower values in spring and higher values in winter. Smoking did not affect the excretion of U-MTBE. The results of this study suggest that U-MTBE is a sensitive and specific marker for the assessment of exposure to traffic exhaust fumes.

Adult↗

PubMedDate not supplied

[Biological monitoring of exposure to solvents: a method for the gas-chromatographic determination of aromatic hydrocarbons in the blood and urine].

A gas chromatographic procedure with dynamic head-space purge and trap preconcentration (HSGC) and FID detection for blood and urinary benzene, toluene, ethylbenzene and xylenes (BTEX) determination at low level exposure is described. Critical steps (sample collection, calibration, HSGC conditions, contamination control) are discussed. The calibration curve is linear in the range 50 ng/l-500 micrograms/l; the calculated detection limit is 50 ng/l for all the considered aromatic hydrocarbons (AH) both in blood and urine; the within-day precision, calculated as variation coefficient (CV) at 400 ng/l and 40 micrograms/l (n = 6) was respectively CV = 13% and CV = 6% for all the studied analytes. The recovery rate was in the range 29-70%, depending on the hydrocarbon and matrix (blood or urine) considered. The procedure was applied to the biological monitoring of 151 workers occupationally or environmentally exposed to BTEX. Occupationally exposed subjects showed blood AH levels of 2-4 order of magnitude higher than environmentally exposed subjects. In white-collar workers exposed to BTEX urban pollution a significant difference in blood and urine levels of AH was observed between nonsmokers and smokers. Nonsmokers showed blood AH median values of respectively benzene = 241 ng/l, toluene = 759 ng/l, ethylbenzene = 140 ng/l, xylenes = 604 ng/l. Significatively higher BTEX blood values were observed in smokers after a median consumption of 5 cigarettes in 5 hours; observed median values were respectively: benzene = 365 ng/l toluene = 1327 ng/l, ethylbenzene = 233 ng/l, xylenes = 794 ng/l.

Air Pollutants, Occupational↗

PubMedDate not supplied

[Biological monitoring of environmental benzene exposure in traffic wardens].

Vehicle exhausts are a well known source of aromatic hydrocarbon pollution in urban environments. The paper reports the results of environmental and biological monitoring of benzene exposure in traffic wardens carried out over a 5-hour workshift. Subjects (n = 131) were grouped according to smoking habits and job task as follows: group (A) 52 nonsmoking office workers, (B) 43 nonsmoking outdoor workers, subdivided into (B1) 36 working on foot and (B2) 7 cyclists; (C) 20 smokers office workers, (D) 16 smokers outdoor workers, subdivided into (D1) 11 working on foot and (D1) 5 cyclists. The median indoor environmental benzene concentration (26 micrograms/m3, n = 50) was significantly lower than the outdoor concentration (45 micrograms/m3, n = 43) (p < 0.01); median exposure value of cyclists was 78 micrograms/m3 (n = 12). For biological monitoring, urinary excretion of trans,transmuconic acid was determined in spot samples collected at 7:30 h (MAit) and 12:30 h (MAft). The MAftA median value (63 micrograms/l, range 2-242 micrograms/l) was not statistically different from MAftB (74 micrograms/l, range 15-216 micrograms/l), while the MAftB2 value of 96 micrograms/l was higher than both MAftB1 (71 micrograms/l) and MAftA. In group (B) there was a relationship between airborne benzene levels and MAftB excretion (y = 17.2 + 1.1x, r = 0.62, n = 35, p < 0.01). The influence of smoking on urinary MA excretion was studied by comparing the results obtained in all nonsmokers (AB) with smokers (CD). MAftCD (192 micrograms/l) was significantly higher than MAftAB (69 micrograms/l) (p < 0.01). In smokers, statistically significant relationships were observed between urinary excretion of MAft (y, microgram/l) and cotinine (x, microgram/l) (y = 83 + 0.08x, r = 0.73, n = 23, p < 0.01), and smoking (x, number cigarettes/day) (y = 87.4 + 4.4x, r = 0.53, n = 29, p < 0.01). Comparison between MAft and MAit median excretion values, calculated for each of the 6 exposure groups, showed that MAft was always higher than the corresponding MAit value. A rough estimate of the total dose of benzene ("index of exposure", EI) inhaled by each subject during the 5-hour working shift as a consequence of air pollution and smoking was also made. Considering the entire group of subjects, a significant association was observed between EI and MAft values (y = 43.4 + 0.39x, r = 0.65, n = 104, p < 0.01). Individual values of MA it were correlated with MAft according to the equation y = 43.6 + 0.82x (r = 0.62, n = 105; p < 0.01) and were also positively associated with EI values (y = 42.3 + 0.20x; r = 0.55; n = 74; p < 0.01). In conclusion, the results suggest that the measurement of urinary MA excretion is a poor indicator for assessing environmental benzene exposure at levels below 100 micrograms/m3, such as those seen in this study; MA can however be reliably used as a biomarker for higher exposures such as those, for example, due to smoking.

Adult↗