[Definition of neurotoxic risk based on the benchmark dose in vitro: illustration with experimental models based on the use of known neurotoxic substances]. / Definizione del rischio neurotossico in base alla dose di riferimento ("benchmark dose") in vitro: esemplificazioni con modelli sperimentali basati sull'uso di sostanze neurotossiche note.

The BMD approach has been used to compare the cell viability (MTT assay) of different rat (C6 and PC12, glial and neuronal, respectively) and human cell lines (D384 and SK-N-MC, glial and neuronal, respectively) after 24-h exposure to the following neurotoxic substances: Manganese Chloride (MnCl2), Methyl-mercury (Me-Hg) and the enantiomers of Styrene Oxide (SO). For all rat and human cell lines, the potency of the examined compounds was: MnCl2 < S-SO < R-SO < Me-Hg. A preliminary comparison with in vivo toxicity data for these substances gave rise to consistent results. Whereas a reasonable agreement between in vitro and in vivo data has been found for Mn and styrene oxide, a wide scatter of LOAEL has been reported for Me-Hg and these appear to be either much higher or lower than the BMD for the MTT assay we observed in vitro.

[Study of the genotoxic effects of exposure to cosmic radiation in flight personnel using cytogenetic and molecular techniques]. / Studio degli effetti genotossici da esposizione a radiazioni cosmiche nel personale aeronavigante mediante tecniche citogenetiche e molecolari.

BACKGROUND: The ever-increasing use of air travel suggests the need to study health risks in flight personnel, by means of correct exposure assessment and evaluation of genotoxic effects. OBJECTIVES: After taking into consideration occupational risk and possible confounding factors, we studied 48 pilots and flight technicians engaged on long-haul flights together with a control group of 48 ground staff, with the aim of evaluating genotoxic effects of cosmic radiation exposure. On 36/48 subjects we also evaluated the presence of DNA damage (single and double strand breaks). METHODS: Traditional cytogenetics, the micronucleus test and FISH analysis, were used to study chromosome aberrations, micronuclei and translocations. The Comet test was used to analyze direct DNA damage (single and double strand breaks). RESULTS: Our findings indicated a significant increase in gaps and breaks and a significant increase of frequency ratio for translocations in pilots compared to controls, but revealed a non-significant difference in unstable aberrations and micronuclei. The Comet test did not show any significant increase of DNA damage in flight personnel with respect to ground staff. CONCLUSIONS: The possibility of a correlation between translocations and cancer risk emphasizes the need to adopt preventive measures for air flight personnel.

[SARS and occupational risk]. / SARS e rischio occupazionale.

SARS is an infectious disease caused by a previously unrecognized human coronavirus, called SARS-associated coronavirus (SARS-CoV). Current information indicates that most transmission is via respiratory droplets coming from a person who is symptomatic with SARS ("close contact"). The aim of our study is to evidence the critical role of the family physician, the first health-care worker who cares with suspected/probable SARS patients, underlying the importance of the correct use and management of the personal protective equipment.

Asbestos exposure assessment by mineralogical analysis of bronchoalveolar lavage fluid.

Mineralogical analysis of bronchoalveolar lavage fluid (BALF) by electron microscopy can represent the most suitable method for assessing asbestos exposure. However, it has been claimed that no standardized or systematic approach to the subject of mineralogical analysis exists. This study aimed to evaluate BALF mineralogical analysis by transmission electron microscopy as biomarker of asbestos fiber load. BALF was examined in 108 exposed workers and 57 patients who underwent diagnostic fiberoptic bronchoscopy for various clinical purposes. Asbestos bodies in BALF were counted with a phase-contrast microscope. Fibers were counted and analyzed by transmission electron microscopy, which showed a significant difference between the two populations and positive results for all exposed subjects. Only 82.2% of the exposed population tested positive for asbestos bodies. Subjects with long-term exposure had higher concentrations of fibers than did those with more recent exposure, probably because of the higher workplace exposure levels in the past. The results of the study confirm that fiber concentration in BALF can be considered as a reliable biomarker of past asbestos exposure, even many years after the end of exposure.

[Physiopathology of repetitive movements and vibrations of the hand-arm system]. / Fisiopatologia dei movimenti ripetitivi e delle vibrazioni al sistema mano-braccio.

This paper is a review of some recent findings in physiopathology of work related upper limb disorders and hand-arm-vibration-syndrome (HAVS). In a first section the data relative to work related upper limb musculoskeletal disorders are collected in three groups referring respectively to the muscle, to the tendon and to the peripheral nerve. Furthermore the physiopathological data are analyzed with respect to the Strain Index proposed by Moore and Garg. In a second section the physiopathological mechanisms of HAVS are summarized.

[Delphi study in the identification of research need in occupational medicine in Italy]. / Studio Delphi per l'identificazione delle priorità di ricerca in medicina del lavoro in Italia.

The aim of the study was to identify the research priorities and strategies in Occupational Safety and Health (OSH) in Italy with a high degree of consensus. Based on the Delphi technique, a two-phase questionnaire was sent to experts at Universities, Local Health Units (ASLs) and Trade Unions. In the first phase, experts were requested to indicate three research topics in the OSH sector. A total of 27 topics for both universities and ASLs and 18 topics for Trade Unions were identified. In the second phase, experts were requested to assign a score from one (low relevance) to five (high relevance) to each topic previously identified. On the basis of a mean score reported for each topic, two ranked lists of priorities, one referred to universities and ASLs the other referred to Trade Unions, were formulated. The highest priority identified by universities and ASLs was occupational carcinogenesis, followed by quality in occupational medicine. Workers' information, education and participation was also identified with a high degree of priority. For Trade Unions, occupational cancers as well as training, information, participation and prevention awareness had the highest priority. Trade Unions also identify small-industries and occupational accidents as topics with high priority for research development. This study allowed a high degree of consensus to be reached regarding the research priorities in the OSH sector in Italy. Differences in the topics identified, or regarding the mean score of topics commonly identified, were related to the origin of the expert recruited to this study (University, ASLs or Trade Unions) and, for universities and ASLs, to the geographical area. In the authors' opinion, the full transfer of existing scientific data to occupational health practice and the harmonization of the priorities identified by this investigation are crucial if the research needs in the OSH sector in Italy are to be met.

Research priorities in occupational health in Italy.

OBJECTIVE: To find a broad consensus on research priorities and strategies in the field of occupational health and safety in Italy. METHODS: A two phase questionnaire survey was based on the Delphi technique previously described in other reports. 310 Occupational safety and health specialists (from universities and local health units) were given an open questionnaire (to identify three priority research areas). The data obtained from respondents (175, 56.4%) were then used to draw up a list of 27 priority topics grouped together into five macrosectors. Each of these was given a score ranging from 1 (of little importance) to 5 (extremely important). With the mean scores obtained from a total of 203 respondents (65.4%), it was possible to place the 27 topics in rank order according to a scale of priorities. RESULTS: Among the macrosectors, first place was given to the question of methodological approach to research in this field, and for individual topics, occupational carcinogenesis and quality in occupational medicine were ranked first and second, respectively. The question of exposure to low doses of environmental pollutants and multiple exposures ranked third among the priorities; the development of adequate and effective approaches and methods for worker education and participation in prevention was also perceived as being an important issue (fourth place). CONCLUSIONS: This study (the first of its kind in Italy) enabled us to achieve an adequate degree of consensus on research priorities related to the protection of occupational health and safety. Disparities in the mean scores of some of the issues identified overall as being research priorities, seem to be linked both to geographical area and to whether respondents worked in local health units or universities. This finding requires debate and further analysis.

[Vaccine prophylaxis: contribution for the control of biologic risk in exposed workers]. / La profilassi vaccinale: contributo per il controllo del rischio biologico nei lavoratori esposti.

Working activities with exposure to biological agents have become a matter of discussion especially after the introduction in Italy of the Law 626/94, in conformity with the EU directive 90/679/EEC. There are many important biological agents that can have infectious, allergic, toxic or carcinogenic effects on the working population. Large occupational groups are exposed to these biohazards, both in agriculture and industry. Vaccination is one of the most beneficial medical practices, which has led to the eradication of such a devastating human disease as smallpox and the almost total elimination of poliomyelitis. Vaccination is also one of the most cost effective prevention measures applicable in this respect. This paper describes the possible vaccinations that employers should make available to employees exposed to biological risk, according to article 86 of Law 626/94.

[Round Table "Role of scientific and professional associations in proposing occupational health programs to regional and national authorities]. / Tavola Rotonda "Ruolo propositivo delle associazioni scientifiche e professionali verso gli organi di governo locale e centrale".

The six participants at the round table were experts in the field of Occupational Prevention working respectively in the Ministry of Health, the National Institute of Occupational Health, the Health Council of Lombardy, the Law-court of Milan, the CGIL Trade Union, and the Lombard Employers Association. All the participants were of one mind on the establishment of working groups within the scientific and professional associations with the aim of preparing and updating occupational exposure limits, diagnostic records, programs of biological and environmental monitoring, etc. Moreover, they stressed the need to establish permanent cooperation between the scientific and professional associations and the regional and national health authorities. These associations can make an important contribution, for example in preparing new preventive guidelines, because they can act faster than the legislative bodies. The validity of these proposals was confirmed by the judge attending the round table. He stated that technical standards proposed by groups of professionals or by scientific associations have usually been taken into consideration when relevant legislation has been applied.

[Prevention, safety and prophylactic measures in occupational HIV infection in Italy, the European Union and the USA]. / Misure di prevenzione, sicurezza e profilassi nell'infezione occupazionale da HIV in Italia, Unione Europea e USA.

Numerous guidelines have been issued by Public Health institutions and related authorities in the last few years for the prevention of HIV infection among occupationally exposed workers. Our study was aimed at comparing the regulations and guidelines on this topic that have recently been adopted by Western countries, also taking into account the impact of the problem in current scientific literature. Health-care workers are the category with the highest risk for occupational exposure to HIV principally associated with accidental needlesticks, skin lesions and percutaneous injuries. In preventive and occupational medicine, Italy, the European Union and the USA have founded their recommendations on universal and specific precautions issued by the Center for Disease Control. Moreover, as long ago as 1990 the Italian Ministry of Health issued official guidelines for the prevention of occupational exposure to bloodborne pathogens. Post-exposure management is crucial for the protection of workers at risk. As a consequence of the failure of some monotherapeutic zidovudine treatments, different countries revised their guidelines and recommended the use of a combination of chemotherapeutic drugs for the post-exposure regimen. However, most of the currently available data are derived from efficacy studies of combined therapy on HIV-infected patients. Therefore, further experimental investigations are needed aimed at evaluating the short- and long-term effects of these treatments in the post-exposure protection of workers at risk for HIV infection.

Dermal exposure assessment of polycyclic aromatic hydrocarbons: in vitro percutaneous penetration from lubricating oil.

OBJECTIVES: Percutaneous penetration of polycyclic aromatic hydrocarbons (PAHs) is affected by various factors connected to exposure conditions. The nature of the matrix, such as that of oil, can strongly affect their percutaneous penetration. Risk assessment should consider these effects. We examined the effect of matrix on percutaneous penetration of PAHs, particularly that of lubricating oil. METHODS: The test apparatus consisted of an in vitro static diffusion cell system using full-thickness monkey (Cercopithecus aetiops) skin as the membrane and saline solution with gentamycin sulfate and 4% bovine serum albumin as receptor fluid. Chemical analysis of PAHs in the samples obtained from cells was carried out by inverse-phase HPCL, and the results were read by spectrofluorimetry. RESULTS: Comparing the penetration of 13 PAHs from a lubricating oil and from acetone solution with artificial sweat resulted in a significantly slower passage from the oil matrix for acenaphthene, anthracene, phenanthrene, fluoranthene, naphthalene, pyrene, fluorene (Mann-Whitney U test, P < 0.05). No significant differences in the passage were found for chrysene because, in the test with oil, its concentration was very often below the detection limit. For benzo[a]anthracene, benzo[b]fluoranthene, benzo[k]fluoranthene, and benzo[a]pyrene it was possible to demonstrate a passage through the skin only when compounds were applied in acetone solution with artificial sweat. CONCLUSIONS: The results of the study suggest the necessity of dermal penetration data relevant for risk assessment, obtained under experimental conditions similar to the real exposure conditions.

Chronic venous disorders and occupation.

BACKGROUND: Chronic venous disorders in the general population are a significant socio-medical pathology. The importance and role of venous pathologies in the occupational field are underestimated and the data in the literature are incomplete and contradictory. METHODS: A study was made of 336 male workers: 112 industry workers, 120 stoneworkers, and 104 office workers. A targeted questionnaire was administered to all workers regarding occupational and extraoccupational risk factors for venous pathologies. The same workers were clinically examined, and a venous check-up and specific tests were done in clinostatic and orthostatic postures. RESULTS: The prevalence of chronic venous disorders, including major and minor pathology, was significantly higher among industrial workers (39.28%) than among stoneworkers (24.16%, P=.019) and office workers (22.11%, P=.010). Only for major pathology was the mean age higher in phlebopathic workers than in non-phlebopathic; furthermore, the proportion of workers standing for >/=50% of the work shift was higher in phlebopathic than in non-phlebopathic. These differences were significant in all working groups. The results showed a positive relationship between the prevalence of phlebopathy and increased age and number of hours spent standing. Considering workers of the same age classes, a higher prevalence of phlebopathy was found between those who stood for >/=50% of their shift and those who stood for <50% of the time. CONCLUSIONS: The results suggest that professions involving standing, particularly for those standing for >/=50% of the shift, can influence the development of chronic venous disorders and a diagnostic clinical protocol to be used by occupational physicians in screening working populations for the prevention of venous disease is suggested.

Long-term exposure to "low levels" of manganese oxides and neurofunctional changes in ferroalloy workers.

Occupational exposure to manganese can cause early neurobehavioral effects in low- or a-symptomatic workers. A battery of neuropsychological tests was administered to a group of 61 ferroalloy male workers and 87 controls. The average (geometric mean) manganese concentrations in total dust at the plant have changed from 1981 to 1997 respectively from 1597.03 micrograms/m3 to 239 micrograms/m3 at the furnace area; from 151.53 to 255.76 micrograms/m3 at the casting area; from 167 to 54.7 micrograms/m3 at the maintenance (welding operations), yielding a current overall value of 54.25 micrograms/m3. A cumulative exposure index was calculated for each alloy worker and the average value (geometric mean) resulted to be 1204.87 micrograms/m3 x years, which divided by the average length of exposure (15.17 years), showed the concentration of 70.83 micrograms/m3 of manganese in total dust. Blood and urinary manganese geometric means resulted significantly higher in the exposed workers (9.18 micrograms/l and 1.53 micrograms/g creatinine, respectively) than in controls (5.74 micrograms/l and 0.40 microgram/g creatinine, respectively). A positive correlation was observed between the airborne manganese concentrations in total dust and blood manganese (n = 55; R = 0.36; R2 = 0.13; p = 0.0068), whereas no association resulted between cumulative exposure index and both blood manganese and urinary manganese. Higher prevalence of symptoms reporting was observed in the alloy workers concerning irritability, loss of equilibrium and rigidity. Tremor parameters including the central frequency and its dispersion, resulted to be statistically different in the exposed workers compared to the controls. Motor functions exploring the coordination of rapid and alternating movements and memory functions resulted to be impaired in the manganese workers. Dose-effect relationships were observed between the cumulative exposure index and some of the test results, whereas no relationship was found with the airborne manganese concentrations and the biological indicators of exposure. These findings are consistent with the existing knowledge of a cumulative mechanism of action of manganese, which must be carefully considered when setting safe exposure levels. In order to be protective for the entire working life, the average annual exposure level should be lower than 100 micrograms/m3.

Prediction of percutaneous absorption from physicochemical data: a model based on data of in vitro experiments.

Correlations between in vitro percutaneous absorption data and physicochemical properties of industrial chemicals are evaluated in order to develop predictive mathematical models based on said properties. Percutaneous diffusion of 16 pounds of occupational interest, eight of which were polycyclic aromatic hydrocarbons (acenaphthene, anthracene, benzo(a)anthracene, chrysene, phenanthrene, fluorene, naphthalene, pyrene), six organophosphorus insecticides (acephate, chlorpyrifos, dimethoate, fenitrothion, methamidophos, omethoate) and two phenoxycarboxylic herbicides (2,4-D, MCPA), were tested in vitro using monkey (Cercopithecus aetiops) skin. The test apparatus consisted of nine static diffusion cells with normal saline, gentamycin sulphate and 4% bovine serum albumin as receiving solution. Test compounds were applied at various concentrations in 30 microliters of acetone solution and determined, in the receiving phase, by chemical analysis. Values for ln Kow (octanol/water partition coefficient) were correlated with experimentally determined values of the permeability constant Kp (r = 0.90, P < 0.001) and lag time (r = 0.81, P < 0.01). Analysis of variance in a model of multiple linear regression between Kp, ln Kow and water solubility [water] of the compounds, showed that the data had a highly significant fit (P < 0.0001). A more general model which also included molecular weight (MW) and vapour pressure was evaluated as well, but the two variables made no substantial difference. Multiple regression analysis between lag time, ln Kow and [water] was significant (P < 0.0001), whereas introduction of vapour pressure and MW as independent variables did not significantly improve the predictive effect on lag time. Our experimental system, therefore, enables the values of Kp and lag time to be predicted with reasonable precision on the basis of ln Kow and [water] values, using the algorithm derived from the multiple linear regression equation.

Solubilization of lead from crystal dust in protein solution (pseudointerstitial fluid) and gastric juice.

Since several workers engaged in polishing and engraving crystal articles were found to have higher than average blood levels of lead (560 micrograms/liter, range 80-560 micrograms/liter), we investigated the hypothesis that crystal dust releases lead in the human body. To test the hypothesis, two types of crystal polishing dusts, having different lead contents, were mixed with human serum diluted 1:3 (pseudointerstitial fluid), gastric juice, and phosphate buffer at pH 9. After 14 days of contact, the diluted serum had extracted 0.620% of the lead in the crystal dust (particle size < 20 microns) containing 25.2% lead and 0.425% of that containing 19.9% lead. After 48 hr in gastric juice, 0.235 and 0.556% of the lead was extracted from crystal dusts (unsieved crystal dusts) containing 25.2 and 19.9% lead, respectively. After 28 days in alkaline solution, 0.358 and 0.304% of the lead was extracted respectively from the same two crystal dusts (unsieved crystal dusts).