Minimization of the impact of rubble production wastes on the environment by their involvement in the compositions of road'building materials

The impact of Taldan crushed stone plant and wastes formed in process of its activity on the environment is considered. About 2.9 million tons of siftings of rock grinding were accumulated in dump massifs with a total area of 600 hectares. Therefore, elimination of accumulated harm to the environment that has arisen over many years of operation of Taldan crushed stone plant is the actual task. One of the technological solutions of liquidation of objects of accumulated harm to the environment based on physicochemical impact on wastes is stabilization or artificial stone formation. Drawing of siftings of rock in soil concrete compositions (artificial stone materials) allows to solve complex of acute environmental problems due to their largetonnage direct use. The use of siftings of rock in road building will contribute to the rational and cost-effective use of natural mineral raw materials, since this process will not entail an increase in the costs of its extraction and processing. A set of modern methods (atomic-emission spectrometry with inductively coupled plasma, scanning electron microscopy, X-ray phase analysis, infrared spectroscopy) were used to study the chemical, phase composition and properties of siftings of rock to substantiate the possibility of its utilization in the composition of soil concrete. It is shown that the introduction of an 8 wt. % of mineral binder and polymer stabilizing additive Element (1, 5, 10 wt. %) allows to get soil concrete with a mark of strength М100.

Artificial stone silicosis: Accumulation of errors in the resurgence of an occupational disease: A qualitative study

BACKGROUND: Exposure to artificial stone machining, under the conditions in which marble workers work with this new product, can cause silicosis. OBJECTIVE: To examine the experiences of marble workers affected, both in workshop and during home installation of countertops, before diagnosis of silicosis. METHODS: Qualitative study in which 10 open-ended semistructured interviews were conducted with marble workers diagnosed with silicosis after machining artificial stone countertops in Cádiz, Spain. Interviews were recorded, transcribed, and coded using a directed content analysis. Codes were organized into themes. RESULTS: Interviews up to 120 minutes and transcript analysis revealed three themes: 1) Heavy exposure for piecework: construction boom in an environment of labor deregulation and high demand for the novel product; 2) Poor working conditions: dry machining of artificial stone without proper protection in the workshop and greater exposure during home installation of countertops; 3) Concatenated legal transgressions: deficiencies in prevention and health surveillance without safety conditions for the correct handling of artificial stone. CONCLUSIONS: The fight against an emerging occupational disease—artificial stone silicosis—should focus on detecting affected workers and avoiding new cases, forcing joint efforts to achieve rigorous compliance with health surveillance and protecting marble workers to achieve healthy and safeworkplaces.

Study of the Behavior of Structural Materials Treated with Bioconsolidant

In this article, the effectiveness of the bioconsolidation technique applied to degraded structural materials is illustrated as a new method of consolidation and conservation of the existing building heritage in a less invasive way. Satisfactory results have been obtained by an experimental campaign carried out through non-destructive diagnostic tests, static destructive mechanical tests, and microstructural analyses on a series of natural stone material specimens and artificial stone materials before and after the use of bioconsolidants. The consolidated specimens have been tested after three to four weeks after the application of the M3P nutritional solution on each specimen. The effect on the microstructure of this technique has also been observed using scanning electron microscope and optical photomicrograph, the formation of new calcium carbonate crystals promoting the structural consolidation of the materials under examination was observed in all the specimens analyzed.

Quantitation of Silica Contents in Lung Explants of Transplanted Patients: Artificial Stone-Induced Silicosis vs. Idiopathic Pulmonary Fibrosis

Spectrophotometric techniques provide qualitative but not quantitative data on lung particles. We aimed to quantitate silica content in biopsies of lung-transplanted silicosis patients by applying X-ray fluorescence (XRF) spectrometry. Lung biopsies of 17 lung-transplanted artificial patients were quantitated for silica and other minerals particles by Niton XL3 XRF spectrometry. Occupational and clinical history data were assessed. Lung biopsies of artificial stone-induced silicosis (ASIS) patients contained significantly higher levels of silica compared to those of idiopathic pulmonary fibrosis (IPF) patients (7284.29 ± 4693.75 ppm vs. 898.88 ± 365.66 ppm, p < 0.0001). Silica content correlated negatively with age, body mass index, and pulmonary function test results. A 1128 ppm silica cut-off value yielded 100% sensitivity and 94% specificity for predicting ASIS (AUC = 0.94, p < 0.0001). In conclusion, XRF measurements in lung biopsies can differentiate between silica and mineral particles in ASIS and IPF.