Position Paper on Asbestos of the Italian Society of Occupational Medicine.

The Position Paper (PP) on asbestos of the Italian Society of Occupational Medicine (SIML) aims at providing a tool to the occupational physician to address current diagnostic criteria and results of epidemiological studies, and their consequences in terms of preventive and evaluation actions for insurance, compensation and litigation. The PP was based on an extensive review of the scientific literature and was compiled by a Working Group comprising researchers who have contributed to the international literature on asbestos-related diseases, as well as occupational physicians with extensive experience in the evaluation of risks and the medical surveillance of workers currently and formerly exposed to asbestos. The PP was drafted and reviewed between 2017 and 2018; its final version was prepared according to the guidelines of AGREE Reporting Checklist. All the members of the Working Group subscribed to the document, which was eventually approved by SIML's Executive Committee. The first section addresses industrial hygiene issues, such as methods for environmental monitoring, advantages and limitations of different microscopy techniques, the potential role of microfibers and approaches for retrospective assessment of exposure, in particular in epidemiological studies. The second section reviews the biological effects of asbestos with particular attention to the diagnostic aspects of asbestosis, pleural changes, mesothelioma and lung cancer. In the following section the criteria of causal attribution are discussed, together with different hypotheses on the form of the risk functions, with a comparison of the opinions prevalent in the literature. In particular, the models of the risk function for mesothelioma were examined, in the light of the hypothesis of an acceleration or anticipation of the events in relation to the dose. The last section discusses topics of immediate relevance for the occupational physician, such as health surveillance of former exposed and of workers currently exposed in remediation activities.

Exposure to asbestos: past, present and future.

This paper summarises the past, present and future of asbestos exposure. The future scenarios as to the mesothelioma incidence in countries, where asbestos has been banned, are discussed.

[A new update of the SIMLII Guidelines on carcinogens]. / Il nuovo aggiornamento delle Linee Guida SIMLII sui cancerogeni.

The second update of the Italian Society of Occupational Medicine and Industrial Hygiene (SIMLII) guidelines on Cancerogens and Mutagens, first published in 2003 and reviewed in 2007, is presented. The general setting of the guidelines remaines unmodified. In this new release some important developments on regulatory system, risk assessment, and health surveillance are discussed. The relevant evolution of the regulatory rules is illustrated in detail, with particular reference to the recent implementation in European Union and in Italy of the Regulation (EC) 1272/2008 on Classification, Labelling and Packaging of substances and mixtures. The recent tendencies of the European Scientific Committee on Occupational Exposure Limits in risk assessment, are presented. Some remarks on the use of new biomarkers in health surveillance, with reference to lung and bladder cancer, are discussed. The more recent results on the effectiveness of the use of LDTC scan on screening in asymptomatic persons at high risk for lung cancer, are presented. The use of this imaging technique in health surveillance of special group of workers (i.e., subjects with relevant past asbestos exposure and smokers) could be adopted.

Follow-up of patients affected by manganese-induced Parkinsonism after treatment with CaNa2EDTA.

In the period of 1998-2004, seven workers affected by manganese-induced Parkinsonism were diagnosed, studied and treated with CaNa2EDTA at our Occupational Health Ward. Biological markers, as well as magnetic resonance imaging and clinical examinations, were used to assess the disease trend. Those workers still employed were immediately removed from exposure. Our results seem to confirm that very good clinical, biological and neuroradiological results can be obtained by timely removal from exposure and chelating treatment, and that amelioration can persist in time. Manganism is, however, a severe condition that can also progress independent of further exposure. Therefore, chelating treatment can be a great aid in overt manganism, but particular attention must be paid to primary prevention, as this disease should now be totally preventable and definitely merits eradication.

Motor neuron disease and optic neuropathy after acute exposure to a methanol-containing solvent mixture.

A 34-years-old floor-layer developed optic neuropathy and motor neuron disease after being accidentally exposed to a solvent mixture containing methanol and other substances. Optic neuropathy is a complication of methanol poisoning, but the onset of a motor neuron disorder resembling amyotrophic lateral sclerosis after the exposure to these substances has not been previously described. The temporal onset of the clinical symptoms, biological plausibility, young age of the patient and absence of neurological disorders in the family history raises suspicion of a possible causative relationship.

Manganese intoxication: the cause of an inexplicable epileptic syndrome in a 3 year old child.

Excess manganese (Mn) can cause several neurotoxic effects, however only a few studies have reported epileptic syndromes related to manganese intoxication. We describe an epileptic syndrome due to manganese intoxication in a 3 year old male child. His blood manganese was elevated, but no other abnormal values or toxic substances were found in blood or urine. The electroencephalogram (EEG) showed a picture of progressive encephalopathy, while brain magnetic resonance was normal. The patient's conditions rapidly worsened to epileptic status despite the use of antiepileptic drugs. Chelating treatment with CaNa(2)EDTA was initiated to remove excess manganese and promptly succeeded in reverting epileptic symptoms. Concurrently, manganese blood levels and electroencephalogram progressively normalized. Thereafter it has been possible to discontinue antiepileptic treatment, and the patient remains in excellent conditions without any treatment.

T1-weighted hyperintensity in basal ganglia at brain magnetic resonance imaging: are different pathologies sharing a common mechanism?

Basal ganglia bilateral symmetric hyperintensity in T1-weighted sequences at magnetic resonance imaging (MRI) is recognized to be due to the presence of manganese deposits. This abnormal finding has been reported in occupational exposures, liver cirrhosis and total parenteral nutrition with unbalanced solutions. However, the same imaging is often observed "by chance" in brain MRIs of patients not belonging to these groups. In order to better understand which are the clinical conditions coexisting with such findings, we decided to study systematically patients which showed this kind of imaging, focusing on their manganese and iron status, as it is known that these two metals have similar properties and that iron-deficiency can competitively increase manganese absorption. The 20 patients studied underwent clinical evaluation and the following laboratory tests: whole blood iron and manganese, hemoglobin, plasma iron, transferrin and ferritin. The neuroradiologic evaluation was integrated by pallidal index calculation, in order to provide a semi-quantitative esteem of the hyperintensity. The patients could be classified into four subgroups: Parkinsonism, anemia, cirrhosis, central nervous system tumors. In 18 out of 20 cases, we found abnormalities in iron and/or manganese-related values. Particularly, iron-deficiency seems to be frequent among patients showing brain MRI abnormalities compatible with manganese deposits in basal ganglia. This observation suggests that iron-deficiency could be an important risk factor for manganese-induced neurotoxicity and should, therefore, be accurately considered and treated.