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A document by the B. Ramazzini College of University Teachers of Occupational Medicine of the Italian Society of Occupational Health and Industrial Hygiene (S.I.M.L.I.I). The aim of this document was to compare the professional competence, training profile and core curricula of the three main specialization courses in the Public Health postgraduate medical area, i.e., Occupational Medicine, Hygiene and Preventive Medicine, and Forensic Medicine, such as contained in the Ministerial Decree (D.M) of 1 August 2005. We set out to identify, using clear and objective criteria, the knowledge and skills that specialists in Hygiene or Forensic Medicine must develop, in accordance with Art. 38 of the new Italian law on safety ahd health at work (D.Lgs 81/2008), in order to be authorized to perform occupational health activities as "Competent Physicians" (CP). The comparison revealed significant differences in structure and content among the three courses. In particular, compared to the course in Occupational Medicine, the courses in Hygiene and in Forensic Medicine both lack clinical training, including diagnostic and therapeutic skills, risk-oriented occupational health activities, biological monitoring, assessment of individual susceptibility, and clinical or instrumental procedures to prevent and detect occupational diseases. Furthermore, the specialization course in Hygiene lacks any training regarding the criteria and methods for assessing the individual worker's fitness for work, while the course in Forensic Medicine lacks any training in occupational risk assessment and management. From this comparison, a list was derived of the education and training debits that specialists in Hygiene or Forensic Medicine should cover (credits) in order to be authorized to perform CP activities as indicated by the new law. A core curriculum is proposed here, based on the corresponding credits, for use as a reference.

Objectives: The present study was aimed at investigating early markers of renal damage and dysfunction in subjects exposed to low doses of mercury from different sources. Different groups of subjects were examined with urinary Hg excretion (HgU) ranging from 0.1 to 35.0 micrograms/g creatinine: 122 occupationally exposed workers, 22 subjects living in a non-polluted area, but consuming large amounts of tuna and sword fish, and 197 controls., Methods: Several markers of renal changes were measured in urine (albumin, fibronectin, beta 2-microglobulin, retinol-binding protein, tubular antigens, N-acetyl-beta-D-glucosaminidase activity) and serum (beta 2-microglobulin and cystatin C). Serum autoantibodies towards collagen, laminin and tubular antigens were assessed in subjects with abnormal renal markers. The role of glutathione-S-tranferases GSTT1 and GSTM1 polymorphisms in the inter-individual variability of biological response to Hg was also investigated., Results: Renal markers were not correlated with HgU. None of such markers differed significantly between exposed workers and controls, except for urinary beta 2-microglobulin, which was decreased in Hg-exposed workers (GM = 55.8 vs 86.6 micrograms/g creatinine), in the absence of any changes in serum concentration. Subjects usually eating tuna and sword fish showed an increased urinary excretion of beta 2-microglobulin, albumin and fibronectin. Serum titres of auto-antibodies did not differ between the groups. Neither in controls nor in exposed workers were the observed differences modified by the GSTM1 and GSTT1 genotypes., Conclusion: The present study did not provide evidence of any changes in kidney integrity and function in subjects exposed to very low levels of inorganic Hg resulting in urinary Hg lower than 35 micrograms/g creatinine. Nor did we obtain evidence of Hg-induced autoimmunity towards kidney components. The potential modifying role of GST polymorphisms could not be clarified in the absence of effects associated with exposure to the risk factor, i.e., to inorganic Hg. Preliminary data suggesting nephrotoxic effects of organic Hg from a diet rich in large fish resulting in increased levels of both blood and urinary Hg--which however did not exceed 20 micrograms/g creatinine--deserves further investigation.

Objectives: The aim of this paper was both to evaluate the internal dose of Hg in occupationally exposed workers (35 Chloralkali workers) compared to that of non occupationally exposed controls (40 workers of the same plant of Portotorres and 22 residents on the island of Carloforte, usual consumers of local fish, mostly tuna fish with relatively high Hg levels) and to assess the relevance of environmental and individual exposure factors linked to lifestyle, sea fish consumption and amalgam fillings., Methods: All subjects filled out a questionnaire concerning the working history and lifestyle. The amalgam fillings area was measured by medical inspection using a standardised schedule attached to the questionnaire. Mercury in urine (HgU) was measured in all cases, while in a subgroup of our study total blood mercury (HgB) and its organic and inorganic component were also assessed. Furthermore, for 8 of the Carloforte group mercury in hair was also available., Results: Values of urinary mercury excretion of the Chloralkali workers were significantly higher (median value of 15.4, range 4.8-35.0 micrograms/g creatinine, 94.3% of the cases having values > 5 micrograms/g creatinine) than those observed both among the reference group (median value of 1.9, range 0.4-5.6 micrograms/g creatinine, 12.5% of the cases having values a little greater than 5 micrograms/g creatinine) and among the residents in Carloforte (median value of 6.5, range 1.8-21.5 micrograms/g creatinine, 59.1% of the cases having values > 5 mcg/g creatinine). The HgU values observed in this group were in turn significantly higher than those of the non occupationally exposed workers living near Sassari (p = 0.03). Only in this last group were the HgU concentrations statistically significantly related to the extension of the amalgam fillings area (Pearson r = 0.53, p < 0.01). In the Carloforte group HgU was significantly related to the number of fish meal consumed per week (Pearson r = 0.48, p < 0.02). HgB (median value of 5.9, range 3.4-21.6 micrograms/l) as well as its inorganic component (median value of 2.4, range 1.8-4.6 micrograms/l) were significantly higher in the Chloralkali group compared to the other two groups. In all cases of the Carloforte group the ratio between the organic component and the total HgB was higher than 85%, while this ratio was significantly lower in the other two groups. The relationship between HgU and HgB was statistically significant, considering both total blood mercury and the inorganic and the organic components separately. A statistically significant relationship between the sea fish consumption per week and both total HgB (Pearson r = 0.82) and the organic component in this matrix (Pearson r = 0.84, p < 0.001) was observed among 16 non-occupationally exposed subjects. However, the significant relationship between organic blood mercury and sea fish consumption was almost entirely supported by the data observed in the Carloforte group. Total hair mercury levels analysed in 8 subjects of the Carloforte group were high (median value of 9.6, range 1.4-34.5 micrograms/g) and significantly related to sea fish consumption, and to both the individual Hg urinary excretion (Pearson r = 0.83) and to the organic component of blood mercury (Pearson r = 0.87)., Conclusions: According to several experimental human and animal trials and to some recent studies on methylmercury toxicokinetic models, our results suggest that the organic compounds absorbed by usual sea fish consumption may be partially demethylated, increasing the inorganic Hg concentration in the kidney and consequently its urinary excretion, as was observed in the Carloforte group.

Objectives: The aim of this paper was to analyse the concentrations of HgU and HgB in three different groups: 122 workers exposed, 18 workers formerly exposed and 196 subjects not occupationally or environmentally exposed to mercury., Methods: All the subjects filled out a questionnaire concerning personal data, lifestyle, occupational or non-occupational exposure to Hg and medical history. The amalgam fillings area was measured by a standardised method., Results: Urinary mercury excretion was significantly greater in the group of the exposed workers respect to the group of subjects not occupationally exposed (Median value of 8.3 micrograms/g creatinine and the 5 degrees and 95 degrees percentile respectively of 2.66 e 23.50 micrograms/g creatinine against Median value of 1.2 micrograms/g creatinine and the 5 degrees and 95 degrees percentile respectively of 0.18 and 5.42 micrograms/g creatinine). U-Hg in formerly exposed workers were comparable to U-Hg in non-occupationally exposed subjects, with a median value of 1.6 micrograms/g creatinine. B-Hg values were similar in the three groups: the median value was 3.1 micrograms/l in the non-occupationally exposed, 4.0 micrograms/l in the exposed workers and 3.9 micrograms/l in the past exposed. These value were not significantly different. Among the considered variables (amalgam fillings, fish consumption, age, sex, alcohol intake, chewing-gum and smoking) dental amalgam and fish consumption were significantly related with the Hg urinary excretion and the B-Hg levels. This is particularly true considering the subjects altogether: for the exposed workers, indeed, the occupational exposure was the most relevant variable., Conclusions: The results of the present research confirmed that the U-Hg excretion in non-occupationally exposed subjects is influenced by amalgam dental fillings. Furthermore, in our study Hg urinary excretion was significantly related with fish consumption. This fact can be explained, according to several recent experimental human and animal trials, considering that methylmercury contained in fish is partially converted, through breakage of the carbon-Hg bond, into Hg inorganic forms, which accumulate in the kidney and have a urinary excretion pathway.

Objectives: To evaluate neuroendocrine and neurobehavioral effects possibly associated with increased dietary intake of organic mercury (Hg), a group of 22 subjects living on the island of Carloforte (south-west Sardinia) was examined, who were regular consumers of tuna fish with relatively high Hg content. This group, never exposed occupationally to either Hg or to other neurotoxic substances, was compared with 22 age-matched controls employed at a chemical plant in Portotorres (northern Sardinia)., Methods: Hg in urine (HgU) and serum prolactin (PRL) were measured in all cases, whereas measurements of total (HgB) and organic blood mercury were available only for 10 subjects from Carloforte and 6 controls. Data about working history and lifestyle (education, smoking habit, alcohol and sea fish consumption) were collected by an interviewer using a standardised questionnaire. Neurotoxic symptoms were evaluated by a self-administered questionnaire, whereas a test battery, including some computerised tests of the Swedish Performance Evaluation System (SPES) to assess vigilance and psychomotor performance, some tests on motor coordination (Luria-Nebraska and Branches Alternate Movement Task) and one memory test for numbers (Digit Span) was administered to assess neurobehavioral changes associated with exposure to dietary intake of organic mercury. In all cases, characteristics of hand tremor were evaluated by the CATSYS System 7.0., Results: HgU values were significantly higher in the Carloforte group (median 6.5, range 1.8-21.5 micrograms/g creatinine) compared with controls (median 1.5, range 0.5-5.3 micrograms/g creatinine). Serum PRL was significantly higher among subjects from Carloforte and correlated with both urine and blood Hg levels. The scores of each item of the questionnaire investigating neurological symptoms were not statistically different in the two groups. In some tests of the SPES battery (Color Word Vigilance, Digit Symbol and Finger Tapping) the performance of the Carloforte group was significantly worse than that of controls, whereas in the other neurobehavioral tests poorer performances by the Carloforte group were not statistically significant. None of the tremor parameters was significantly different comparing the two groups. Multivariate analysis--controlling for education level and other covariates--carried out for the Symbol-Digit Reaction Time and for the Branches Alternate Movement Task (BAMT) showed that organic Hg concentration in blood was the most significant factor negatively affecting individual performance in these tests. Serum PRL was correlated with some neurobehavioral tests (Digit Symbol, Finger Tapping and BAMT)., Conclusions: Some of the neurobehavioral tests were sensitive enough to discriminate groups with different Hg body burden, even in the low-dose range. However, the pattern of results suggests adverse neurobehavioral effects, especially on psycho-motor coordination, with a significant dose-effect relationship, mostly associated with long-term exposure to low levels of organic mercury due to the usual consumption of large fish with relatively high levels of Hg in the flash.

Objectives: To assess early effects on the Central Nervous System due to occupational exposure to low levels of inorganic mercury (Hg) in a multicenter nationwide cross-sectional study, including workers from chloro-alkali plants, chemical industry, thermometer and fluorescent lamp manufacturing. The contribution of non-occupational exposure to inorganic Hg from dental amalgams and to organic Hg from fish consumption was also considered., Methods: Neuropsychological and neuroendocrine functions were examined in a population of 122 workers occupationally exposed to Hg, and 196 control subjects, not occupationally exposed to Hg. Neuropsychological functions were assessed with neurobehavioral testing including vigilance, motor and cognitive function, tremor measurements, and with symptoms concerning neuropsychological and mood assessment. Neuroendocrine functions were examined with the measurement of prolactin secretion. The target population was also characterized by the surface of dental amalgams and sea fish consumption., Results: In the exposed workers the mean urinary Hg (HgU) was 10.4 +/- 6.9 (median 8.3, geometric mean 8.3, range 0.2-35.2) micrograms/g creatinine, whereas in the control group the mean HgU was 1.9 +/- 2.8 (median 1.2, geometric mean 1.2, range 0.1-33.2) micrograms/g creatinine. The results indicated homogeneous distribution of most neurobehavioral parameters among exposed and controls. On the contrary, finger tapping (p < 0.01) and the BAMT (Branches Alternate Movement Task) coordination test (p = 0.05) were associated with occupational exposure, indicating an impairment in the exposed subjects. Prolactin levels resulted significantly decreased among the exposed workers, and inversely related to HgU on an individual basis (p < 0.05). An inverse association was also observed between most neuropsychological symptoms and sea fish consumption, indicating a "beneficial effect" from eating sea fish. On the contrary, no effects were observed as a function of dental amalgams., Conclusions: In conclusion, this study supports the finding of early alterations of motor function and neuroendocrine secretion at very low exposure levels of inorganic Hg, below the current ACGIH BEI and below the most recent exposure levels reported in the literature.

Objective: The immune system is a target for the toxic effects of inorganic mercury, both in humans and animals. In humans it has been observed that occupational and environmental exposure to inorganic mercury may cause both clinical (autoimmunity, hypersensitivity) and subclinical effects (cellular and humoral immunologic variable modifications). To obtain a better definition of these effects with respect to the exposure levels, a multicentre study was performed on 117 workers exposed to very low doses of inorganic mercury and 172 subjects from the general population of the same geographical area with environmental exposure to mercury from dental amalgams and dietary fish intake., Results: The white blood cell count was included in the normality range for all subjects and there was no difference between exposed and non exposed subjects. The immunologic variables studied showed an increase of the CD4+ and CD8+ number in exposed workers compared to non-exposed subjects, with a statistically significance only for CD4+, while no difference was observed regarding CD4+, CD8+, NK+ percentage and CD4+/CD8+ ratio. A significative decrease of serum IL-8 and an inverse correlation between serum levels of this cytokine and HgU were observed in exposed workers compared to non exposed subjects. No association between immunologic variables and both dental amalgams and dietary fish intake was found in subjects not occupationally exposed to inorganic mercury., Discussion: The decrease in IL-8 serum levels observed in exposed workers might suggest an immunosuppressive effect of occupational exposure to very low doses of inorganic mercury. This result suggests the need to revise of current HgU BEI after further definition of its prognostic significance.

The paper reports the results of a longitudinal study of 1478 workers in the primary aluminium industry in Italy (aluminium reduction with the pre-baked anode process) covering the prevalence and incidence of chronic obstructive lung disease, chronic bronchitis and bronchial asthma, and analysis of lung function deterioration over time (annual decline in FEV1) in relation to occupational exposure and individual non-occupational features. The incidence of respiratory symptoms of chronic cough and expectoration was significantly higher among electrolytic shop workers, in whom the annual decline in FEV1 was also significantly greater. In this group the incidence and prevalence of asthmatic manifestations was particularly high compared to casting and workshop workers. Asthmatic symptoms showed a short latency period related to exposure in potrooms and seems to be characterized by a marked deterioration in lung function over time even after withdrawal from exposure.

The standard mortality rates (SMRs) were calculated for 1148 workers of a primary aluminium plant in Portovesme, Sardinia, hired between 1971, when production started, and 1980. Status (living or decreased) was ascertained as at 31 December 1990 and the relationship between observed and expected deaths with respective 95% confidence limits were calculated on the basis of age-specific regional rates for each calendar year of the follow-up. The SMR for all causes was 81 with confidence limits between 61 and 108 based on a total of 48 deaths. Mortality due to malignant neoplasms did not differ from the expected rate. The observed deaths due to lung cancer were decidedly less than the expected number (3 observed versus 4.7 expected). A significant excess of cancer of the pancreas was observed with special reference to anode production, based, however, on only 3 observed cases against 0.8 expected. In the absence of a more precise definition of the causes of death, of the environmental exposure levels and of the non-occupational confounding factors, and considering the young age of the cohort under study, it is at present doubtful whether the excess of cancer of the pancreas can be associated with work in the primary aluminium industry. The results should therefore be taken as preliminary, indicating that further studies are required.

A group of 26 male long-distance runners performed 3 cycle ergometer tests of progressively increasing intensity up to exhaustion. The tests were performed on 3 different days. The workload increased as follows: 30 Watts every 3 min (test I), 10 Watts every min (test II), and 30 Watts every min (test III). Ventilatory and gas exchange measurements were averaged every 30 sec during each test. The heart rate (HR) was monitored continuously by ECG. In each test the anaerobic threshold (AT) was determined using ventilatory and gas exchange indices (VE, VCO2, VE/VO2). The work load on exhaustion and power at AT were the same comparing test I with test II, but these values were significantly higher in the 30 Watts/1 minute test. Conversely, maximal oxygen uptake (VO2 max) and the VO2 observed at anaerobic threshold were comparable in the 3 protocols. The slopes of VO2, VCO2, VE and HR against the work load (Watts) were identical in test I and II, but were slower in test III. However, no differences in the ventilatory and heart rate patterns versus oxygen uptake were observed comparing the three exercise tests. These results suggest a good comparability between the 30 Watts/3 min test and the 10 Watt/1 min protocol. Furthermore, for workloads below AT, a steady state was attained at the 3rd minute of each phase during test I, while oxygen uptake and other cardio-respiratory variables were underestimated during the protocol in which phases of 30 Watts were maintained only for 1 minute.(ABSTRACT TRUNCATED AT 250 WORDS)