Creation of a database of occupational and environmental concentrations of crystalline silica dust for the purpose of assessing past and current exposures.

BACKGROUND: Professional exposure to respirable dust containing crystalline silica is of great interest for the serious lung diseases resulting from exposure. METHODS: During the period 1986-2019, 3611 exposure data to crystalline silica were collected from companies in central Italy. The data were divided and statistically analyzed based on the sampling system (Cyclone Dorr Oliver, CIP 10-R, Cyclone GS3, SKC plastic selector, Cyclone Higgins-Dewell and Cyclone Lippmann) and the ATECO code (code of economic activity, Italian acronym, used to classify companies when they interface with public institutions) of the companies in which they were collected. For each ATECO code, the division was made according to the type of sampling (personal or static) and the descriptive statistics of the data were calculated. RESULTS: Overall, for personal samples, 8.8% of the data exceeds 0.1 mg/m3, 19.6% exceeds 0.05 mg/m3 and 33.8% exceeds 0.025 mg/m3, the limit values set by the EU Directive 2019/130, suggested by the SCOEL and published by ACGIH respectively. The ATECO codes with the highest worker exposure (geometric means 0.067 and 0.069 mg/m3) were 23.31.00 (manufacture of ceramic tiles for floors and walls) and 23.42.00 (manufacture of ceramic sanitary ware), while the lowest exposure is found in 81.29.91 (cleaning and washing of public areas, removal of snow and ice including shedding of sand) with a geometric mean of 0.002 mg/m3. DISCUSSION: Despite the general reduction over time, there are still many sectors in which data are higher than the current occupational exposure limits; especially in these sectors it is necessary to implement the measures to fully assess worker exposure.

Cytological analysis of bronchoalveolar lavage fluid in asbestos-exposed workers.

BACKGROUND: Asbestos-related lung diseases are a group of heterogeneous disorders with different pathogenesis and prognosis. Very few studies investigated the BALF cell profile of asbestos exposed workers. The existence of a relationship between bronchoalveolar lavage fluid (BALF) cellular pattern and specific diagnosis and/or asbestos exposure biomarkers would allow the identification of effect biomarkers useful in the follow up of asbestos-exposed workers and in the diagnosis of asbestos-related diseases. OBJECTIVES: To assess BALF cell profile in formerly asbestos-exposed workers and its relationship with asbestos fibre (amphibole and chrysotile) and asbestos body (AB) concentrations. METHODS: 113 male workers formerly exposed to asbestos underwent bronchoscopy with bronchoalveolar lavage and were retrospectively enrolled. 35 of them were affected by pleural plaques and 10 were affected by asbestosis. Pulmonary functional tests (PFT), BALF cellular pattern, BALF mineralogical analysis with asbestos fibres and AB counting were performed in each patient. A statistical analysis with a multivariate linear regression model was adopted. RESULTS: From the statistical analysis of data a direct correlation between pack-years and BALF macrophages was found. Inversely correlation between pack-years and BALF lymphocytes was detected. There was not relationship among BALF cellular pattern, PFT values, specific diagnosis, BALF AB count or BALF asbestos fibre concentration. DISCUSSION: BALF cellular pattern does not seem to be related to asbestos exposure biomarkers like AB and asbestos fibre concentration in BALF. Instead, smoke habit can induce an increase in BALF macrophages and a decrease of BALF lymphocytes count.

Asbestos exposure biomarkers in the follow-up of asbestos-exposed workers.

Health surveillance of asbestos exposed workers should be stratified according to the exposure level. Unfortunately there is a lack of information regarding asbestos exposure in many working places and markers of asbestos exposure are often needed. The aim of the study was to assess the reliability of different dose and effect biomarkers in the follow up of asbestos-exposed workers. Mineralogical analysis of bronchoalveolar lavage fluid (BALF) as a biomarker of asbestos fibre burden was performed in a population of 307 male subjects occupationally exposed to asbestos. Using nonparametric statistical methods 8 variables were analyzed with respect to asbestos-related diseases and working sectors. The existence of a relationship between serum soluble mesothelin-related peptides (SMRP) and asbestos exposure levels was also investigated. Concentrations of amphiboles, chrysotile and asbestos bodies in BALF were higher in patients with asbestosis as well as in railway industry workers. A correlation between the onset of non malignant asbestos-related diseases and the levels of SMRP concentration was not found. This study confirms that fibre concentration in BALF may be considered as a reliable biomarker of previous asbestos exposure, whereas SMRP does not appear to be influenced by asbestos exposure levels.