Occupational exposure to crystalline silica in artificial stone processing

Respirable Crystalline Silica (RCS) is a hazardous substance with known effects that can be well correlated with exposure levels that still persist in many traditional sectors, such as construction or stone processing. In the past decade, exposure scenarios for RCS have been found in the sector of artificial stone processing. The aim of this study is to evaluate the levels of RCS in facilities specialized in the production of artificial stone countertops and other accessories for the furnishing of kitchens, bathrooms, and offices after the introduction of some preventive technical measures such as wet processing or local exhaust ventilation systems. The study involved 51 subjects in four facilities. Personal silica exposure assessment was carried out using GS3 cyclones positioned in the breathing zone during the work shift. Quantitative determination of silica was carried out by X-ray diffraction analysis. Respirable dust levels were in the range 0.046-1.154 mg/m³ with RCS levels within the range <0.003-0.098 mg/m³. The highest exposure was found in dry finishing operations. Although there was a remarkable reduction in RCS exposure levels compared to what was observed in the past before the introduction of preventive measures, the data still showed hazardous exposure levels for some of the monitored activities.

Occupational Exposure to Flour Dust. Exposure Assessment and Effectiveness of Control Measures

The adverse effects associated with exposure to flour dust have been known since the 1700s. The aim of the study was to assess the occupational exposure to flour dust in Italian facilities, identify the activities characterized by the highest exposure, and provide information to reduce workers’ exposure. The study was performed in different facilities such as flourmills (n = 2), confectioneries (n = 2), bakeries (n = 24), and pizzerias (n = 2). Inhalable flour dust was assessed by personal and area samplings (n = 250) using IOM (Institute of Occupational Medicine) samplers. The results showed personal occupational exposure to flour dust over the American Conference of Governmental Industrial Hygiene (ACGIH) and the Scientific Committee on Occupational Exposure Limit (SCOEL) occupational limits (mean 1.987 mg/m³; range 0.093–14.055 mg/m³). The levels were significantly higher for dough makers in comparison to the dough formers and packaging area subjects. In four bakeries the industrial hygiene surveys were re-performed after some control measures, such as installation of a sleeve to the end of pipeline, a lid on the mixer tub or local exhaust ventilation system, were installed. The exposure levels were significantly lower than those measured before the introduction of control measures. The exposure level reduction was observed not only in the dough making area but also in all bakeries locals.

How to improve performance and prevent burnout in safety representatives

BACKGROUND

The present work is part of a greater research project, aimed to examine Safety Representatives' (SRs) role, twenty years after the appointment of this figure.

OBJECTIVES

The study aims to investigate the role of some personal and organizational dimensions in the promotion of SRs' well-being, in terms of reducing burnout and improving performance.

METHODS

The study involved 455 SRs operating in North East Italy. They completed a self-report questionnaire, regarding conflicts with co-workers, ethical conflict, training satisfaction, work engagement, performance, and burnout.

RESULTS

Structural equation models show that work engagement partially mediates (γ=-0.52, p<0.001; β=0.23, p<0.01) the relationship between conflict with co-workers and performance (γ=-0.26; p<0.01), as well as partially mediating (γ=0.14, p<0.05; β=0.23; p<0.01) the relationship between training satisfaction and performance (γ=0.21, p<0.001). Moreover, it totally mediates the relationship between conflict with co-workers and burnout (γ=-0.52, p<0.001; β=-0.40, p<0.001), as well as totally mediating the relationship between training satisfaction and burnout (γ=0.14, p<0.05; β=-0.40, p<0.001). Finally, ethical conflict is positively associated with burnout (γ=0.047, p<0.001).

CONCLUSIONS

This study provides useful information about the improvement of SRs' well-being, highlighting the importance of their involvement in this role.

Multiorgan accelerated silicosis misdiagnosed as sarcoidosis in two workers exposed to quartz conglomerate dust

Introduction

Clusters of silicosis cases have been reported in the fabrication of quartz conglomerate, a new high-silica-content artificial stone for kitchen and bathroom benchtops (countertops).

Aim

We describe two cases of accelerated-type silicosis with hepatic granulomas arising in workers exposed to artificial quartz conglomerates.

Methods

A confident diagnosis of multiorgan silicosis was based on high level of respirable silica in the workplace, typical radiological alterations in chest high-resolution CT, histological findings in the lung and liver, and detection of silica crystals in both tissues by phase-contrast polarising light microscopy and scanning electron microscopy and energy dispersive spectroscopy.

Results

The development of the disease <10 years after the first exposure is consistent with an accelerated-type of silicosis. Compared with other studies related to quartz conglomerate exposure, we determined that the levels of airborne crystalline silica during activity in the finishing area were between 0.260 and 0.744 mg/m3, that is, much higher than the threshold limit value according to American Conference of Governmental Industrial Hygienists (0.025 mg/m3). Moreover, liver granulomas were associated with accumulation of crystalline silica particles in the hepatic tissue.

Conclusions

Quartz conglomerate fabrication is a potentially dangerous occupation. General practitioners and physicians should have awareness of this newly described occupational hazard. Accurate occupational history is critical in avoiding misdiagnosis, as silicosis caused by inhalation of dust from artificial quartz conglomerates may exhibit atypical presentation. These features seem to be related to the extremely high level of silica exposure and, possibly, to an increased toxicity of the dust generated in this process.

PharmML in Action: an Interoperable Language for Modeling and Simulation

PharmML is an XML-based exchange format created with a focus on nonlinear mixed-effect (NLME) models used in pharmacometrics, but providing a very general framework that also allows describing mathematical and statistical models such as single-subject or nonlinear and multivariate regression models. This tutorial provides an overview of the structure of this language, brief suggestions on how to work with it, and use cases demonstrating its power and flexibility.

Mixed meal ingestion diminishes glucose excursion in comparison with glucose ingestion via several adaptive mechanisms in people with and without type 2 diabetes

AIMS

To study the integrative impact of macronutrients on postprandial glycaemia, β-cell function, glucagon and incretin hormones in humans.

METHODS

Macronutrients were ingested alone (glucose 330 kcal, protein 110 kcal or fat 110 kcal) or together (550 kcal) by healthy subjects (n = 18) and by subjects with drug-naïve type 2 diabetes (T2D; n = 18). β-cell function and insulin clearance were estimated by modelling glucose, insulin and C-peptide data. Secretion of glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) were measured, and paracetamol was administered to estimate gastric emptying.

RESULTS

In both groups, the mixed-meal challenge diminished glucose excursion compared with glucose challenge alone, and insulin levels, but not C-peptide levels, rose more than after the mixed meal than after glucose alone. β-cell function was augmented, insulin clearance was reduced and glucagon levels were higher after the mixed meal compared with glucose alone. GLP-1 and GIP levels increased after all challenges and GIP secretion was markedly higher after the mixed meal than after glucose alone. The appearance of paracetamol was delayed after the mixed-meal challenge compared with glucose alone.

CONCLUSIONS

Adding protein and fat macronutrients to glucose in a mixed meal diminished glucose excursion. This occurred in association with increased β-cell function, reduced insulin clearance, delayed gastric emptying and augmented glucagon and GIP secretion. This suggests that the macronutrient composition regulates glycaemia through both islet and extra-islet mechanisms in both healthy subjects and in subjects with T2D.

Pharmacometrics Markup Language (PharmML): Opening New Perspectives for Model Exchange in Drug Development

The lack of a common exchange format for mathematical models in pharmacometrics has been a long-standing problem. Such a format has the potential to increase productivity and analysis quality, simplify the handling of complex workflows, ensure reproducibility of research, and facilitate the reuse of existing model resources. Pharmacometrics Markup Language (PharmML), currently under development by the Drug Disease Model Resources (DDMoRe) consortium, is intended to become an exchange standard in pharmacometrics by providing means to encode models, trial designs, and modeling steps.

[Effectiveness trial for prevention of occupational injuries in the wood processing industry]

BACKGROUND

Training is a key tool to improve prevention and safety management at the workplace. Few studies have aimed at assessing quality of training and its outcomes.

OBJECTIVES AND METHODS

This paper describes the rationale, design, content, and evaluation of an ongoing randomized controlled trial aimed at assessing the effectiveness of a training programme designed to reduce the risk of occupational injuries among employees of the wood processing industry.

DISCUSSION AND CONCLUSIONS

Well designed, targeted training programmes could represent a feasible means of reducing work injuries by improving employers' behaviour and attitudes towards safety; nevertheless, these kinds of interventions have a considerable impact both in terms of human resources and in terms of cost. For these reasons, assessment of effectiveness and knowledge-sharing should be considered as essential phases of injury prevention programmes.

[Return of immigrants: a cluster analysis of mesotheliomas among residents of the Veneto region who used to work at the ETERNIT AG factory at Niederurnen, Switzerland]

We identified 5 mesotheliomas among Italian migrant workers who returned home and settled in the Veneto Region, after employment at the ETERNIT AG factory in Switzerland. During the 1970s the factory employed about 1000 workers and the presence of Italian migrants was relevant. The cluster confirms that migration for work has caused exposures to carcinogenic substances and confirms that neoplastic diseases are occurring among those resettled in Italy and helps explaining the high occurrence of mesotheliomas in this country.

[Pleural mesothelioma in women in the Veneto Region who used to work as rag sorters for textile recycling and paper production]

The paper reports 9 cases of mesothelioma diagnosed by means of histology or cytology that were observed among women resident in the Veneto Region, Northern Italy, whose only activity that could involve exposure to asbestos was as rag sorter. These cases are part of a group of about 260 subjects with mesothelioma whose entire working and residential history has been collected. The women worked as rag sorters between the 1940's and 1960's in textile recycling (8 cases) or (one case) at a paper mill where cotton was used for paper production. The work as rag sorter helps to explain the high proportion of mesotheliomas among women with an occupational exposure to asbestos.

Longitudinal study of alveolitis in hypersensitivity pneumonitis patients: an immunologic evaluation

Cells recovered from bronchoalveolar lavage were studied, both from a phenotypic and functional point of view, in 18 patients with hypersensitivity pneumonitis (HP) during a prolonged follow-up. A series of monoclonal antibodies against different lymphocyte subpopulations, including T cells, T cell subsets, and natural killer (NK) cells have been used. In some cases, an immunohistologic analysis of lung tissue sections has also been performed. The NK activity has been evaluated with regard to the in vitro function. At the time of the first evaluation, a high number of CD8+ cells with an imbalance of CD4/CD8 ratio had been demonstrated in patients with HP. Consecutive bronchoalveolar lavage evaluations demonstrated a persistent increase of CD8+ cells and a reversal of CD4/CD8 ratio in patients who continued to be regularly exposed to etiologic antigens at work (W+). In the same cases, a persistent increase of NK cells was demonstrated. Cytotoxic cells demonstrated a persistently enhanced in vitro lytic function during the follow-up, even though there appeared to be a trend toward the normal range. Patients who continued to live in agricultural environments but were not further exposed to specific antigens at work (W-) exhibited a recovery of CD4+ cells, a decrease in CD8+ cells, and an increase of CD4/CD8 ratio to the normal range 6 months after the first observation. Immunohistologic analysis, performed at the time of the first evaluation, demonstrated a diffuse infiltration of lung parenchyma by CD8+ cells, both in W+ and W- patients.(ABSTRACT TRUNCATED AT 250 WORDS)

[Comparison of various methods of evaluating auditory damage caused by chronic acoustic injury]

The purpose of the present study was to compare the most common hearing damage criteria, based upon pure tone audiometric data. We examined 1086 workers with different intensity and duration of noise exposure. After consecutive selections, 455 subjects, subdivided into four exposure groups, were studied. The 12 considered criteria showed a widespread difference in their sensitivity: the percentage of hearing impaired subjects ranged from 3.3 to 24.2% in the whole population. The most sensitive criteria evaluated the hearing loss at 2 and 4 KHz. The evaluation of the hearing loss at 3 and 6 KHz did not modify the percentage of subjects bearing an handicap. The authors suggest the average hearing loss at 2 and 4 KHz as a criterion to be used for preventing and epidemiological purposes.