[Mesothelioma and acceleration]. / Il mesothelioma e la anticipazione degli eventi.

INTRODUCTION: Taking a publication by Berry in 2007 (3) as a cue, this paper presents in didactic form the topic of acceleration of events as a consequence of a harmful exposure and extends the proposed approach to the case of the asbestos-mesothelioma relationship. METHODS: Berry's approach was applied to lung cancer and mesothelioma data. RESULTS: The effects of the acceleration of events are presented as a function of age at onset in exposed subjects, relative risk, scale factor, in addition to age and geographical variability of the relationship between age and mesothelioma rates. DISCUSSION: The discussion regards the general characteristics of the method of acceleration, its meaning and interpretation, and the difficulties associated with its application in the context of diseases with low occurrence; the conditions, applicability constraints, and specific results in the case of mesothelioma; the epidemiologic meaning of acceleration and the difficulties of its extension to individual subjects.

III Italian Consensus Conference on Malignant Mesothelioma of the Pleura. Epidemiology, Public Health and Occupational Medicine related issues.

The III Italian Consensus Conference on Pleural Mesothelioma (MM) convened on January 29th 2015. This report presents the conclusions of the 'Epidemiology, Public Health and Occupational Medicine' section. MM incidence in 2011 in Italy was 3.64 per 100,000 person/years in men and 1.32 in women. Incidence trends are starting to level off. Ten percent of cases are due to non-occupational exposure. Incidence among women is very high in Italy, because of both non-occupational and occupational exposure. The removal of asbestos in place is proceeding slowly, with remaining exposure. Recent literature confirms the causal role of chrysotile. Fibrous fluoro-edenite was classified as carcinogenic by IARC (Group 1) on the basis of MM data. A specific type (MWCNT-7) of Carbon Nanotubes was classified 2B. For pleural MM, after about 45 years since first exposure, the incidence trend slowed down; with more studies needed. Cumulative exposure is a proxy of the relevant exposure, but does not allow to distinguish if duration or intensity may possibly play a prominent role, neither to evaluate the temporal sequence of exposures. Studies showed that duration and intensity are independent determinants of MM. Blood related MM are less than 2.5%. The role of BAP1 germline mutations is limited to the BAP1 cancer syndrome, but negligible for sporadic cases. Correct MM diagnosis is baseline; guidelines agree on the importance of the tumor gross appearance and of the hematoxylin-eosin-based histology. Immunohistochemical markers contribute to diagnostic confirmation: the selection depends on morphology, location, and differential diagnosis. The WG suggested that 1) General Cancer Registries and ReNaM Regional Operational Centres (COR) interact and systematically compare MM cases; 2) ReNaM should report results presenting the diagnostic certainty codes and the diagnostic basis, separately; 3) General Cancer Registries and COR should interact with pathologists to assure the up-to-date methodology; 4) Necroscopy should be practiced for validation. Expert referral centres could contribute to the definition of uncertain cases. Health surveillance should aim to all asbestos effects. No diagnostic test is recommended for MM screening. Health surveillance should provide information on risks, medical perspective, and smoking cessation. The economic burden associated to MM was estimated in 250,000 Euro per case.

[Health expenditures for cases of pleural mesothelioma]. / Quanto costa in prestazioni sanitare un paziente con mesothelioma della pleura?.

Through the study of 65 cases of probable pleural mesothelioma currently under discussion in 4 criminal trials in the Lombardy Region, who died between 2002 and 2015, this study aimed to provide economical information regarding the health expenditures sustained by the Regional Health Service (RHS) for providing hospitalization, outpatient services and drugs to such patients. Health information regarding the services provided for the cases under study were electronically retrieved from the RHS information system. For each pleural mesothelioma case the costs (on average) were about 67,000 euros, 37,000 of which were spent after the date of diagnosis. Drugs formed the largest part of health expenditure (about 37,000 euros per person). Per capita expenditures showed a peak near (before and after) the date of diagnosis, rising when approaching the date of death and with increasing age of the patient, and did not vary with survival time. This information, reported for the first time in detail in this paper, will be useful for out-of-court agreements and for setting up reimbursement schemes, and describe per capita expenditures which are higher than estimations proposed in recent criminal trials in Italy and to those reported in the international literature.

[Pier Luigi Viola and vinyl chloride: notes that were never published]. / Pier Luigi Viola e ii cloruro di vinile: alcuni appunti mai pubblicati.

The name and work of Pier Luigi Viola (1917-1985) are unequivocally connected with the history of the discovery of the toxic effects of vinyl chloride, cancer in particular. A biography and a bibliography of Professor Viola are still lacking but his work is well documented; equally well known is his professional career as an occupational physician who spent his entire working life as an employee of one single industrial group, Solvay; his work was dedicated firstly to taking care of the health of the workers of the Corporation and not only in Italy, and secondly to organizing the occupational health departments of all Solvay's establishments in Italy. This positive connection between occupational physician and scientist has recently been challenged in certain historical reconstructions of the discovery of vinyl chloride's carcinogenicity: in particular, these reconstructions (which we do not consider to be coherent with the facts) depict Viola as in constant conflict with his employer. As crucial support to this view are offered on the one hand a statement by Viola, in 1980, that "At the basis of every discovery there is frequently the poetical imagination of a researcher who is always alone in facing the difficulties of the research, difficulties that rise up against him like a wall reaching up to the sky"; and on the other the supposed failure to find some of Professor Viola's notes which should reflect his spiritual testimony, and from which should emerge "the suffering, the torments, and the pressures of that initial period". The true history is very different: the notes do exist: they were personally delivered to one of the authors (PB) by Viola's widow a few months after his death; they are in fact the first pages of a planned book on vinyl chloride that Viola never actually succeeded in writing. In these pages Viola developed some personal reflections from which it is clear that he was conscious of having been in the centre ofa fantastic adventure in the field of scientific research in which he also played the principal role; there is no mention whatsoever of any conflict or contrast between Viola and Solvay. In fact, the backdrop to this story reflects the typical dynamics of scientific research. The article continues with the publication of Viola's handwritten notes: in this way the supposed "mistery of the missing notes" is solved.

[Acroosteolysis in PVC autoclave cleaners: history of an occupational disease]. / Nascita, sviluppo e scomparsa di una malattia professionale: la acroosteolisi dei pulitori manuali di autoclavi nella produzione di PVC.

OBJECTIVES: This paper examines the history of an occupational disease which has now disappeared: acroosteolysis of manual tank cleaners in the production of polyvinyl chloride (PVC), which is a rare disease characterized by destructive alterations of the distal phalanges of the hands. METHODS: All the available literature on this disease was examined. The history of acroosteolysis was studied within the general framework of the history of the discovery of adverse health effects of exposure to vinyl chloride, and this history was studied up to the end of the 1960's. RESULTS: The disease was observed for the first time in mid-1963 in Belgium (Jemeppe) in a chemical plant operated by Solvay, and affected two workers whose job was the manual cleaning of vessels used for the polymerization of vinyl chloride; similar cases occurred in almost all PVC production plants all over the world, but not in the plants where the main activity was the production of vinyl chloride monomer (VCM). Little more than one hundred cases are described in the scientific literature, and this number increases by a few dozen if we consider known but unpublished cases. These figures confirm the rarity of the disease, which peaked at the end of the 1960's and disappeared during the 1970's, probably due to the complete elimination of manual reactor cleaning. Observation of the disease lasted no more than fifteen years and the disease was not replicated in experimental conditions on animals. DISCUSSION: The disease was clinically characterized, had a short latency (from several months to several years), was rare and unequivocally linked to the manual cleaning of PVC polymerization tanks. However many questions still remain open: the period when the disease first appeared (many years after the start of PVC production in the world), the etiology of the disease (the most accredited hypothesis considers three concomitant factors: a chemical factor--one of the many substances used during polymerization, and particularly vinyl chloride monomer, a physical factor--microtraumas of the fingers during manual cleaning, individual susceptibility), the pathogenetic mechanism (in particular: the role of skin, respiratory, or digestive system, as entrance door), a method (or test) to screen subjects potentially predisposed to the disease. In our view acroosteolysis of manual tank cleaners in PVC production is an occupational disease which is distinct from "vinyl chloride disease" as identified by Viola (1974).

[La Medicina del Lavoro: 100 volumes]. / La Medicina del Lavoro: 100 volumi.

With these pages La Medicina del Lavoro starts its 100th volume, so we have yet another historical occasion to celebrate the oldest occupational health journal in the world that is still publishing. Over the last few years we have had many occasions to celebrate, for example several anniversaries of the Journal (the 80th volume in 1989, 90 years in 1992, 100 years in 2001); the centenary of the foundation of the Clinica del Lavoro "Luigi Devoto" of Milan in 2001; the celebration of the 300 years' anniversary of the publication of De Morbis Artificum Diatriba by Bernardino Ramazzini, and we obviously hope to continue for many years to come in this positive outlook. One hundred volumes makes for a very large collection, with the highs and lows ofthe Journal's history (here we mean the variations in number of pages and physical size of the Journal). It is thanks to the Editors-in-chief(there have been very few so we can cite them all: Luigi Devoto, 1901-1936; Luigi Preti, 1936-1941; Enrico Vigliani, 1943-1992; e Vito Foà, 1992 to the present); the contributors who in various ways and with varying degrees of commitment but always with an exceptional personal participation, that it has been possible to reach 100 volumes, starting with C. Moreschi who, along with Luigi Devoto, was the first and sole editor at the Journal's foundation; up to the present extended and impressive editorial board; the printers (from the first. Tipografia Cooperativa, Via dei Molini in Pavia, to the latest: Casa Editrice Mattioli in Fidenza); the sponsors, including the most evident who, via advertising (rather limited as a matter offact), directly gave information about themselves, but also those who have often been or are behind the scenes, ensuring fundamental support which is not visible; content. articles, news, events, reports, ideas, opinions, photographs, tables, numbers... etc, which are really impossible to sum up. But the true collection which, for obvious reasons, cannot be individually named, consists of the people and the ideas that have enriched the history of the Journal in its over 100 years of existence. And the subscribers, above all, who by their almost anonymous presence have been the true guarantors of the Journal's ife. And of course the contributors who with their articles have consigned a part of their lives to history. Starting from 1925 we counted nearly 11.000, a really grand number. It would be wonderful if we could invite them all to a hypothetical (and impossible) grand convention to simply say "Thank you, your contributions will not be forgotten". There have been 100 volumes but in actual fact the Journal is more than 100 years old. It was founded in Pavia in 1901 as Il Lavoro-Rivista di fisiologia, clinica ed igiene del lavoro, and between 1901 and 1910 only three volumes were published, then, due to the difficulties during the First World War and the immediate post-war years, there were no issues in 1916, 1918 and 1919. Issues finally became regular in 1920 with volume 11; from that moment on not one issue was missed and the Journal even got through the Second World War without interruptions. In 1925, with volume 16, it took on the name that still distinguishes it to-day: La Medicina del Lavoro, "the official standard bearer of a work of enormous scientific, social and political content" as Luigi Devoto presented the event at the time. The first few years of the Journal were difficult ones (with only three volumes published in 10 years) to the effect that events such as the First International Congress on Occupational Diseases (Milano, 1906), the foundation of the International Commission for Occupational Health (1906), the First National Italian Congress on Occupational Diseases (Palermo, 1907), and above all the inauguration of the Clinica del Lavoro in Milano (20 March, 1910) are not reported in the Journal, which by 1911 had resumed publication but had moved to Milan. Many years have passed since those first three volumes and in the meantime we have moved on to another century and another millenium: this brings new opportunities, new responsibilities, new perspectives, new objectives, but also new subscribers, new contributors, new authors, and new topics. We would like to conclude by repeating the undertaking made "20 volumes ago": The Editorial Board wishes to thank everyone and take the opportunity to renew our unfaltering commitment to work well by ensuring our full respect for authors and readers so as to contribute, via the pages of La Medicina del Lavoro, to spreading love and knowledge of our discipline.

[A simple method for risk assessment and its application to 1,3-butadiene]. / Una proposta metodologica per la valutazione del rischio: l'esempio del 1,3-butadiene.

BACKGROUND: This paper presents a risk assessment exercise applied to 1,3-butadiene, a probable carcinogenic agent, in the context of the activity of the Scientific Committee on Occupational Exposure Limits (SCOEL) of the European Commission. Data on cumulative exposures and relative risks for leukaemia in humans were derived from the open literature. METHODS: A variety of excess relative risk models were applied taking into consideration, in a life-table fashion, mortality from leukaemia by age. RESULTS: As an example of the outcome of the method, results are presented for a 1 ppm exposure (each year) lasting for a working lifetime. They show that in a population of 1,000 adult males experiencing mortality rates similar to those of the 1981 male population of England and Wales, occupational exposure to 1 ppm of 1,3-butadiene for each year of a working life (40 years between the age of 20 and 65) will cause from 0 to 7.1 extra leukaemia deaths between the age 20-85 years, in addition to the 5.1 leukaemia deaths expected to occur in the absence of exposure to 1,3-butadiene. A summary of the estimates, in terms of excess leukaemia deaths, obtained for 0.1 ppm, 0.2 ppm, 0.5 ppm, 1.0 ppm, 2.0 ppm, 5.0 ppm, and 10 ppm of exposure (each year) is also presented. CONCLUSIONS: The method can be applied to predict the risk of carcinogenic agents for which dose-response data exist and no health-based limit value can be established. Results are consistent with those of previous risk assessments based on similar assumptions

Effect of shift work on body mass index: results of a study performed in 319 glucose-tolerant men working in a Southern Italian industry.

OBJECTIVE: To examine the influence of shift work on metabolic and cardiovascular risk factors in subjects working in an industry sited in Apulia, Southern Italy. DESIGN: Cross-sectional study of metabolic effects of shift work in glucose tolerant workers in a chemical industry in southern Italy. SUBJECTS: The subjects included 319 glucose tolerant male individuals, aged 35-60 y. MEASUREMENTS: Anthropometric parameters (body mass index (BMI) and waist-to-hip ratio (WHR)), fasting concentrations of glucose, insulin, and lipids (total cholesterol, HDL-cholesterol, triglycerides), the sum of glucose levels during 75 g-oral glucose tolerance test (Sigma-OGTT), and systolic and diastolic blood pressure (SBP and DBP, respectively). RESULTS: The prevalence of obesity was higher among shift workers compared to day workers, whereas body fat distribution was not different between the two groups. Shift workers had higher BMI than day workers, and shift working was associated with BMI, independently of age and work duration. Shift workers had significantly higher SBP levels, which were independently influenced by BMI, but not by shift work, thus suggesting that the difference in SBP may well be mediated by the increased body fatness. CONCLUSION: In workers of an industry sited in Southern Italy, shift work may be directly responsible for increased body fatness and is indirectly associated with higher blood pressure levels and some features of metabolic syndrome.

[Causality link in criminal law: role of epidemiology]. / Nesso di causalità in materia penale: il ruolo dell'epidemiologia.

This paper focusses on the role of epidemiology in demonstrating causality in criminal trials of toxic tort litigation. First of all, consideration is given of the specificity of the criminal trial and of the role of the epidemiologist as expert witness. As a second step the concept of causality is examined separating general from specific (individual level) causality. As regards general causality, strategies based on some criteria (example: Bradford-Hill criteria) are contrasted with approaches that do not consider causality a matter of science but one of health policy; and specific methods frequently used (meta-analysis, risk assessment, International Boards evaluation,....) are discussed, with special reference to the adoption of high-level standards and to the context of cross-examination. As regards individual level causality the difficulties of the epidemiologic approach to such evaluation are stressed, with special reference to topics like expected value, attributable risk, and probability of causation. All examples are taken from Italian court trials. A general comment on the difficulties of using the criminal trial (dominated by the "but for" rule) for toxic tort litigation and on the opportunity to switch to trials (civil, administrative) with less stringent causal rules ("more probable than not") is offered, with a consideration also of what are called "class actions".

[Occupational epidemiology: from analysis of the apparent to investigation of the unknown]. / Epidemiologia occupazionale: dall'analisi dell'apparente alla ricerca dell'ignoto.

This paper, as a contribution for the centenary celebration of the establishment of the "Clinica del Lavoro Luigi Devoto" in Milan (Italy), presents a brief 30 year history of the activities of its Department of Occupational Epidemiology. Studies and methodological contributions that characterized the first decade of activity are presented and grouped under the heading of analysis of known health effects. The second decade was dominated by the studies and activities that originated from the Seveso accident (dioxin), with an initial interest towards molecular epidemiology, which became increasingly relevant during the third decade when we addressed topics like melanoma, lung cancer, and benzene, in addition to dioxin. More traditional occupational approaches were not dismissed and cohort mortality studies are currently under way (textile dyeing and finishing industry, sulfuric acid, tetrafluoroethylene). Pros and cons of the epidemiologic approach are discussed in the context of occupational health and the strength of its methodological apparatus is suggested as a fundamental tool for studying adverse occupational health effects. In contrast, it is stressed how occupational epidemiology has been poorly used in the application of law 626/94. Considering that contemporary epidemiology is much more inclined towards the discovery of new work-related risks (electromagnetic fields, air pollution) than the description of known health effects, the paper suggests that occupational epidemiology enlarge its interests: people and environment outside the factories might be good candidates for study.

[The epidemiologist in the courtroom: various arguments to start a discussion]. / L'epidemiologo in tribunale: qualche ragionamento per iniziare la discussione.

This paper focusses on some topics peculiar to the presence of the epidemiologist in the courtroom and suggests an initial inventory of questions that might be addressed. Epidemiology and law have peculiarities that must be recognized but a specific collaboration between these expertises is necessary. First of all, it is important to admit that scientific discussion is different from courtroom discussion: some simple examples give an idea of the different ways in which the discussion may proceed in each of the contexts and of the difficulties in using traditional epidemiologic tools. Secondly, the concept of general causality (whether an agent can cause a disease) and specific causality (whether an agent did cause a plaintiff's disease) are briefly reviewed, and the role of epidemiology in addressing both question is discussed. The last point regards the use of epidemiologic methodology in the courtroom context, with particular reference to errors, study design, and literature evaluation: a minimum set of criteria for quality assessment is requested.

Health effects of dioxin exposure: a 20-year mortality study.

Follow-up of the population exposed to dioxin after the 1976 accident in Seveso, Italy, was extended to 1996. During the entire observation period, all-cause and all-cancer mortality did not increase. Fifteen years after the accident, mortality among men in high-exposure zones A (804 inhabitants) and B (5,941 inhabitants) increased from all cancers (rate ratio (RR) = 1.3, 95% confidence interval (CI): 1.0, 1.7), rectal cancer (RR = 2.4, 95% CI: 1.2, 4.6), and lung cancer (RR = 1.3, 95% CI: 1.0, 1.7), with no latency-related pattern for rectal or lung cancer. An excess of lymphohemopoietic neoplasms was found in both genders (RR = 1.7, 95% CI: 1.2, 2.5). Hodgkin's disease risk was elevated in the first 10-year observation period (RR = 4.9, 95% CI: 1.5, 16.4), whereas the highest increase for non-Hodgkin's lymphoma (RR = 2.8, 95% CI: 1.1, 7.0) and myeloid leukemia (RR = 3.8, 95% CI: 1.2, 12.5) occurred after 15 years. No soft tissue sarcoma cases were found in these zones (0.8 expected). An overall increase in diabetes was reported, notably among women (RR = 2.4, 95% CI: 1.2, 4.6). Chronic circulatory and respiratory diseases were moderately increased, suggesting a link with accident-related stressors and chemical exposure. Results support evaluation of dioxin as carcinogenic to humans and corroborate the hypotheses of its association with other health outcomes, including cardiovascular- and endocrine-related effects.

[Liver angiosarcoma in humans: epidemiologic considerations]. / Angiosarcoma del fegato nell'uomo: considerazioni epidemiologiche.

A review of the available literature on angiosarcoma of the liver in an epidemiologic perspective shows that this cancer is rare (0.5-2.5 cases every 10,000,000 persons). It escapes current mortality statistics; it presents peculiar diagnostic difficulties even when histologic material is scrutinized by panels of pathologists; it occurs in both gender at every age (also in children); estimated latency is long (10-40 years, in occupational cases) or very long (60 years and above, in non-occupational cases). Thorotrast, arsenic, and vinyl chloride monomer are frequently listed as risk factors but, along with other substances (steroids, hemochromatosis, diethylstilbestrol, phenelzine, urethane, cyclophosphamide, oral contraceptives) they contribute to explaining the occurrence of no more than 20% of the published cases. Focussing on subjects exposed to vinyl chloride monomer, the published cases were all males aged 35-75 years, with an average latency of 22 years (range 10-40), in jobs with a potential for a high, or very high exposure to VCM (mainly as autoclave cleaner) started before 1970, and limited to a small number of factories. No evidence of a relationship between environmental (non occupational) exposure to VCM and angiosarcoma of the liver emerges from the available literature. We conclude that in more than 25 years of research, apart from the case of vinyl chloride, the etiology of this type of cancer has remained unchanged and largely unknown.

[Bernardino Ramazzini and "Medicina del Lavoro"]. / Bernardino Ramazzini e "la Medicina del Lavoro".

Three hundred years after the first edition of Ramazzini's "De Morbis Artificum Diatriba", this paper reviews all the articles on the work of the great Master of Carpi that have been published over a century in the ninety volumes of "La Medicina del Lavoro". Since the first issue of the journal in 1901, many authors have submitted papers which revisited and commented on the work of Ramazzini, particularly in anniversary years (1914, the anniversary of his death, 1933 and 1983, anniversaries of his birth), but only Luigi Devoto was capable of fully understanding the methodology introduced by Ramazzini, transforming it into practical applications which he listed in ten fundamental actions. Mainly for this reason and considering that Ramazzini had been practically ignored for two centuries, it was decided to consider the Devoto period as the "true Ramazzini era". The death of the founder of the journal in 1935 marked the unexpected beginning of a long silence, lasting up to 1983, during which not one paper on Ramazzini was published in "La Medicina del Lavoro". It is concluded that a comparison between the diseases described by Ramazzini and those of to-day is of no practical use and that a tribute to Ramazzini is simply necessary in recognition of his contribution to the birth and development of occupational medicine, but is nonetheless insufficient. What is also needed, following in the footsteps of the founder of this journal and of the Clinica del Lavoro of Milan, is to reinterpret Ramazzini's methods in modern terms in the perspective of the ten actions he proposed, bearing in mind that possibilities exist to-day whereby his efforts can be completed and further enlarged in terms of practical applications.

Prevalence and histologic features of transfusion transmitted virus and hepatitis C virus coinfection in a group of HIV patients.

BACKGROUND: A recently identified DNA transfusion-transmitted virus has been associated with post-transfusion non-A to G hepatitis. AIM: To determine the prevalence of transfusion-transmitted virus in patients with human immunodeficiency virus infection. Its clinical role in the pathogenesis of liver disease was also evaluated in patients with transfusion-transmitted-virus hepatitis C virus coinfection compared with those with hepatitis C Virus infection alone. PATIENTS AND METHODS: We evaluated 312 HIV-hepatitis C virus coinfected patients (225 males, 87 females). All underwent screening for transfusion-transmitted virus DNA using a nested polymerase chain reaction technique. In some transfusion transmitted virus-DNA positive patients, we performed a phylogenetic analysis. In 56 patients (20 transfusion-transmitted-virus-hepatitis C virus and 36 hepatitis C virus alone), liver biopsy was collected. RESULTS: The prevalence of transfusion-transmitted virus was 113/312 (36%). The genotype distribution was similar to that reported in other studies. No difference in liver histology was found between the two groups. CONCLUSION: Transfusion-transmitted virus infection is common in human immunodeficiency virus patients. We found no histologic differences between liver biopsy specimens from patients coinfected with transfusion-transmitted virus plus hepatitis C virus compared with those infected with hepatitis C virus alone. Transfusion-transmitted virus is not clearly associated with a distinct liver injury.

[Bernardino Ramazzini. Ante litteram epidemiologist]. / Bernardino Ramazzini epidemiologo ante litteram.

Bernardino Ramazzini, born in Carpi in 1633 and deceased in Padua in 1714, is universally renowned father and founder of occupational health. This paper will present Bernardino Ramazzini under a different perspective, and will show that during his scientific career he continuously maintained the attitude of a modern epidemiologist. Reviewing all his scientific papers, and many papers commenting his activity, we present four major areas in which Ramazzini expressed in a direct and convincing way his epidemiologic culture: the epidemiologic constitutions and the work done mainly on physical subjects while he was in Modena; the general architecture of his most important book (De Morbis Artificum Diatriba); the first full description of an episode of environmental pollution which occurred in Finale Emilia in 1689 (in his book this episode is reported in the chapter describing the diseases of chemicals); the opening lectures of some academic years he gave while he was teaching, mainly, in Padua. To our knowledge the epidemiological attitude of Bernardino Ramazzini is not recognized yet in epidemiology textbooks.

Mortality study in an Italian oil refinery: extension of the follow-up.

This article present the results of the extension of the follow-up of a cohort of workers employed in an Italian oil refinery. 1,583 workers employed in 1949-1982 in a northern Italy oil refinery plant were followed-up for mortality as of May 31, 1991. Environmental measurements documented potential exposure to benzene. Standardized mortality ratios (SMR) and their 95% confidence intervals (95% CI) were calculated using as references national (1949-1968) and regional mortality rates (1969-1991). Elevated mortality from lymphoma (seven deaths, SMR 190, 95% CI 76-391) and leukemia (eight deaths, SMR 225, 95% CI 97-443) was observed. No consistent trends by length of employment or time since first exposure were apparent. Nonetheless, the excess risk was particularly and significantly increased among workers with 15 or more years of employment, and 30 or more years since first employment. The findings of elevated mortality from leukemia and lymphoma are in agreement with those of other oil refinery studies. Chance, confounding, or other biases might have played a marginal, if any, role in determining the results. Exposure to benzene is a biologically plausible explanation.

Respiratory mucus transportability is impaired in foundry workers: a longitudinal study.

Mucus transportability impairment can prolong the permanence of occupational inhalable noxae within ciliated airways. A reliable, non-invasive indicator of mucus transportability is the Normalized Frog Palate Transport Rate (NFPTR). The aim of this 3-year prospective study was to compare NFPTR between a group of 166 foundry workers (E) and a group of 133 power plant workers (NE). In the first and third years of the study, workers underwent: clinical examination, spirometry, NFPTR, chest radiography. In both plants, environmental concentrations of respiratory irritants were well below the limits set by the American Conference of Governmental Industrial Hygienists. Both groups were homogeneous for age and smoking habits. Mean NFPTR was significantly lower in E than in NE in the first and third years of the study, and in smokers in comparison with non-smokers, at the end of the follow-up. NFPTR impairment was significantly associated with occupational exposure in the first and third years of the study. In the third year, a decline in NFPTR was associated with exposure, smoking habits, FVC and FEV1/FVC.100. At the end of the study, the means of FVC, FEV1 and PEF were significantly lower in E. No cases of pneumoconiosis were observed. In this study, low doses of foundry respiratory irritants were associated with impairment of mucus transportability; the consequent slowing of mucociliary clearance increased internal doses of foundry airborne noxae.