Polycyclic Aromatic Hydrocarbons Exposure Assessment in a Refractory Brick Production.

In a refractory brick manufacturing company a qualitative and quantitative determination of the sources of occupational exposure to polycyclic aromatic hydrocarbons (PAHs) was obtained in order to validate targeted hygiene measurements. The study included the assessment of PAHs contamination of work surfaces by wipe-sampling, cutaneous exposure by hand washing, contamination of personal protective equipments (gloves) by extraction in solvent, and airborne PAHs concentration in atmospheric samples. Biomonitoring was also carried out by measurement of urinary 1-hydroxypyrene (1-OHPU) in three groups of workers (packaging, production, and controls). The surface contamination sampling was performed in production, packaging, and in other departments (external area) in theory less contaminated by PAHs. Two different areas were identified within the production, one included surfaces that were regularly cleaned (A area) and one included data from non-cleaned surfaces (B area). To confirm the source of exposure, a clear correspondence was observed between the percentage of the single compounds in the binder and those measured in wipes and air samples. As far as the wipes are concerned, the concentrations of phenanthrene, anthracene, fluoranthene, pyrene, benzo(a)pyrene (BaP), and the total PAHs mixture were higher in the B area than the A area of production. The same happened between the A area and the other two departments. According to results of the statistical analysis, these differences were significant. These results were confirmed by the hand washing data and the analysis of PPE. On the other hand, a marked difference does not exist between the packaging department and the external area. In air samples, the differences were much less evident with only higher concentrations of anthracene and total PAHs between production as a whole and the other two departments. Biological monitoring showed 1-OHPU values significantly higher in production workers than in packaging workers. In conclusion, the analysis of the wipes demonstrated that the production B area has a higher surface contamination compared to the production A area and the packaging department. In the absence of a significant difference in air concentrations of PAHs between A and B areas, this is attributable to surfaces not subject to cleaning. Results confirm that the measurement of surface contamination represents a valid tool for the assessment of sources of exposure to PAHs in the workplace.

Skin photoaging in farmers occupationally exposed to ultraviolet radiation.

BACKGROUND: Most personal exposures to UV radiations occur from outdoor activities and several studies detected a significant association between skin cancer and outdoor occupation. OBJECTIVE: The aim of the study was to ascertain the prevalence of photoaging signs in a population of Italian farmers and in a population of indoor workers taking account of confounding factors. METHODS: 169 farmers and 198 indoor workers were classified for skin phototype and for skin photoaging, moreover 13 variables were taken into account. Marginal permutation tests were adopted for statistical analysis. RESULTS: Farmers were significantly older than the indoor workers. In workers occupationally exposed to UV photoaging increased with increasing age and years of occupational exposure to sunlight The distribution of skin phototype did not show significant differences in the two populations, while farmer showed a higher degree of photoaging than indoor workers. CONCLUSIONS: Even if farmers were older than the in door workers it seems that outdoor work produces a higher degree of photoaging.

[Dose and effect biomarkers in the diagnosis of asbestos-related diseases and health surveillance of exposed workers]. / Gli indicatori biologici di dose ed effetto nella diagnostica delle patologie asbesto-correlate e nella sorveglianza sanitaria degli ex-esposti.

The aim of the study was to assess the reliability of the indicators of dose and effect in the health monitoring of asbestos exposed workers. In 49 cases out of 158 studied workers (31%) asbestos-related diseases were diagnosed following ATS criteria (2004). Using nonparametric statistical methods (permutation tests) 6 variables were analyzed with respect to asbestos-related diseases and working sectors, demonstrating a difference in the concentration of amphiboles (p < 0.01), greater in patients with asbestosis and workers involved in asbestos removal from railway carriages. There was not a correlation between mesothelin and amphiboles, chrysotile and total fibers concentrations (Spearman test).

Measurement of asbestos fibre concentrations in fluid of repeated bro-choalveolar lavages of exposed workers.

OBJECTIVES: The aim of this study was to assess the reliability of asbestos fibre concentration in bronchoalveolar lavage fluid (BALF) by carrying out the mineralogical analysis of BALF at different times in the same patient and comparing the results. METHODS: Twenty two patients underwent diagnostic fibreoptic bronchoscopy twice: the first was to assess the past asbestos exposure and the second for different clinical reasons. Mineralogical analysis of BALF was carried out. RESULTS: In 16 patients (72.7%), a reduction of concentration in BALF of all asbestos fibres was observed. The concentrations of both chrysotile and amphiboles in the first bronchoalveolar lavage (BAL) were related to their concentrations in the second BAL and the observed differences were not statistically significant. A significant decrease in asbestos body concentration between the first and the second BAL was found (Wilcoxon test, P < 0.01). CONCLUSIONS: The reliability of the fibre concentration in BALF as a marker of past asbestos exposure seems quite good. In most cases, it allows us to distinguish workers in different classes of exposure and gives useful information on the pattern of exposure. Uncertainties related in general to lung residues and in particular to mineralogical analysis of BALF (mainly due to the high coefficient of variation (CV) at low fibre concentrations and the results of the statistical analysis on total fibres) suggest that this biomarker is more likely suitable for a qualitative/categorical approach to exposure assessment than a quantitative one.

Photorefractive keratectomy in high myopic defects with or without intraoperative mitomycin C: 1-year results.

PURPOSE: To study the results of the prophylactic use of mitomycin C (MMC) to reduce haze formation and refractive regression after excimer laser photorefractive keratectomy (PRK) for high myopic defects (>5 diopters). METHODS: Prospective, consecutive, observational study. A total of 124 eyes of 62 patients were divided into two groups of 31 patients, 62 eyes each (Groups A and B). Only Group A was treated with MMC 0.02%. The data of the two groups of eyes, related to the best-corrected visual acuity (BCVA), to the difference of refraction pre- and post-treatment, and to the corneal haze, were analyzed through combined permutation tests by using the NPC Test software . RESULTS: BCVA of Group A, 1 year after treatment, was better than that of the control Group B (one-sided p value = 0.013): Group A - 3 eyes (4.8%) had a loss of a decimal fraction and no eyes > 1; Group B - 13 eyes (20.9%) had a loss of a decimal fraction and 1 eye (1.6%) of 2. There was a smaller difference between attempted and achieved SE correction in Group A with respect to Group B (one-sided p value = 0.068): Group A - 43 eyes (69.3%) within +/- 0.50 D; Group B - 31 eyes (50%) within +/- 0.50 D. there was a smaller incidence of corneal haze in the group for which MMC was used (one-sided p value = 0.005). CONCLUSIONS: In this study, the application of MMC 0.02% solution immediately after PRK produced lower haze rates and had better predictability and improved efficacy 1 year after treatment.

[Evaluation of sources of mercury absorption through studying urinary mercury levels in the general population]. / Valutazione delle fonti di assorbimento di mercurio tramite lo studio dei livelli di mercurio urinario della popolazione generale.

OBJECTIVES: The number of instances where mercury exposure is possible outside the workplace are numerous, with the main source being amalgam dental fillings and diet. It is also possible to envisage environmental exposure in subjects resident in areas where there is existing environmental contamination. This is probably what happened in Tuscany where past mining activity in the Monte Amiata area may have been the cause. This study estimated the concentration of urinary mercury (HgU) in non-occupationally exposed subjects from southern Tuscany, with the aim of evaluating the sources of mercury absorption in the general population. METHODS: A questionnaire aimed at collecting specific information on factors which might influence the uptake of mercury was used. 164 subjects were studied: 82 subjects (41 males, 41 females) came from the Monte Amiata area and the other 82 (41 males, 41 females) from the Province of Siena. In this way it was possible to evaluate the elements associated with everyday life which may have influenced the presence of the metal in the urine. Since the distribution of the variables cannot be assumed multivariate normal as usual, a recently-proposed method based on a permutation procedure was adopted that allows the analysis of the variables as well as the single marginal analyses, without assuming any model for the distribution of variables. RESULTS AND CONCLUSIONS: The results showed significantly lower levels of HgU in the subjects from the Monte Amiata area. Highly significant differences were demonstrated in the population which was sub-divided according to number and surfaces of amalgam fillings, use of contact lenses and type of water drunk (p < 0.001). Correlations between the levels of HgU and the investigated variables were not observed. It was confirmed that mercury uptake is simultaneously influenced by many factors. Probably the presence of higher levels of mercury in the environment in the Monte Amiata area is a factor of minor importance compared to others, especially the number of amalgam fillings, in determining mercury absorption in the general population.

[In vitro study of transcutaneous inorganic mercury absorption from solid soil]. / Studio in vitro dell'assorbimento transcutaneo del mercurio inorganico dal terreno solido.

OBJECTIVES: Skin is such an important route of absorption of mercury compounds that the ACGIH has assigned them a skin notation. Soil has been recognised as a potential source of exposure to chemical contaminants. It therefore seems advisable to establish maximum daily exposure levels for mercury in soil. In the past, areas adjacent to certain industries and smelters were heavily contaminated by mercury. For example, on Monte Amiata in Tuscany, which was an important mercury mining and production centre in the past, several areas have been polluted. To understand the dermal uptake of chemicals bound to soil and dust, information on the pure substance is helpful but does not seem sufficient. Other factors must be accounted for, that can easily be reproduced and controlled in in vitro experiments. METHODS: Using an in vitro diffusion cell system and human skin, we studied percutaneous penetration of mercury chloride (HgCl2) at different concentrations, with particular emphasis on skin absorption from soil. The test apparatus consisted of a flow-through diffusion cell system. Dermotomed human cadaver skin was used as the membrane, while the receiving liquid was a saline solution with 6% PEG-20 oleyl-ether and gentamycin sulphate. Mercury chloride was applied at two different concentrations using a buffered solution and soil as vehicles. RESULTS AND CONCLUSIONS: Increments of percentage of absorption at the different hours were found to be significantly lower in the cells where the higher concentration of mercury chloride was applied. In the receiving fluid of cells where soil was used as vehicle, the concentration of mercury was always below the detection limit. Skin contamination with soil containing inorganic mercury does not seem to be a dermal risk.

Arterial blood gas analysis and alveolar-arterial oxygen gradient in diagnosis and prognosis of elderly patients with suspected pulmonary embolism.

BACKGROUND: Arterial blood gas analysis (BGA) remains a first-step diagnostic approach in patients with suspected pulmonary embolism (PE). The aim of this study was to evaluate BGA parameters in elderly patients with suspected pulmonary embolism for diagnosis and 14-day prognosis. METHODS: We performed a retrospective cohort observational study of 6 years (1994-1999) in a 60-bed acute geriatric ward of University Hospital in Siena, Italy. Room air arterial oxygen partial pressure (pO2), arterial carbon dioxide partial pressure (pCO2), pH, arterial oxyhemoglobin saturation (SO2), and alveolar-arterial oxygen gradient [D(A-a)O2] were performed on hospital admission of 75 patients with confirmed PE (CPE) and were compared with data from 43 patients with unconfirmed PE (UCPE). The same parameters of 54 CPE surviving patients were compared with 21 CPE nonsurviving patients. RESULTS: Significantly lower PO2 and SO2, and higher DA-aO2 were found in CPE patients. Respiratory alkalosis was found in one third of the patients in both groups (no significant difference). In the CPE group, there was a significantly lower SO2 in nonsurviving patients, without significant differences for the other parameters. Metabolic acidosis was significantly more frequent in nonsurviving patients. CONCLUSION: More severe hypoxemia, oxyhemoglobin hyposaturation, and higher D(A-a)O2 are associated with the diagnosis of PE in elderly patients. Respiratory alkalosis is less frequent than in younger patients, and metabolic disorders are negative prognostic indicators.

Length of hospitalization in elderly patients with community-acquired pneumonia.

Community-acquired pneumonia (CAP) is a serious social and medical problem in the elderly. Mortality, hospitalization and length of stay increase with age. The aim of this study was to determine the risk factors associated with prolonged hospital stay in elderly patients with CAP. Clinical and laboratory data were collected for 115 community-living patients, 65 years old and over, admitted to the geriatric ward of a University Hospital from 1995 to 1998 because of symptoms and signs of pneumonia confirmed by a pulmonary infiltrate on chest x-ray. We divided the patients into two groups, with length of stay more than 13 days (70 patients, cases), and length of stay less than 13 days (45 patients, controls) according to Diagnosis Related Groups criteria for complicated and uncomplicated pneumonia, respectively. A prolonged hospital stay was associated with a higher fever peak and a higher number of days with fever (p<0.005), greater comorbidity (p<0.001), urinary catheterization and secondary urinary infections (p<0.001), higher erythrocyte sedimentation rate (p<0.001), dehydration (p<0.005), and caloric-proteic malnutrition (p=0.01). In conclusion, knowledge of the risk factors for prolonged hospital stay in elderly patients with CAP may be used to identify high-risk patients, prevent the risks with prophylactic measures, and contain the costs of hospitalization.