Abstract  BIOSIS COPYRIGHT: BIOL ABS. RRM LITERATURE REVIEW HUMAN TOXICOLOGY ASBESTOS FIBERS INHALED INDUCED LUNG INJURY RESPIRATORY SYSTEM LUNG INJURY FIBROSIS TOXICITY RESPIRATORY SYSTEM DISEASE ASBESTOS-INDUCED

Abstract  Berg examines the intersection of science and politics in the case of one such issue--naturally occurring asbestos. This story is of an ongoing environmental health dilemma involving disputes over risk, testing methods, remediation, costs, and impact on commercial interests. But it is also the story of how these conflicts altered the life path of one environmental health professional.

Abstract  One of the most widely used means of distributing water to homes is through asbestos-cement pipe that have nowadays, substituted other materials used traditionally. Several modifications on the pipe surface can occur depending on the quality of the water that flows through them producing asbestos fibers leaching which causes some of the water characteristics to change. The pH, hardness, alkalinity, temperature and dissolved oxygen and carbon dioxide are the main factors that can affect water aggressiveness. The Aggressiveness Index (AI) is given by the formula: AI= pH + log (A x H) where: A= total alkalinity as CO3Ca in mg/l. H= calcium hardness as CO3Ca in mg/l. being: IA minor than 10 very aggressive water. 10 minor o equal than IA and minor o equal than 12 moderately aggressive water. IA major than 12 non aggressive water. (Amer. Wat. Works Assoc., 1977). However this index is not a direct measure of water corrosivity but rather is an indicator since it does not take into account the presence of possible protective coating by certain water constituents. Hydrographic basin and season period influence the aggressiveness of water and consequently its behaviour in the water distribution systems. It can be concluded that drinking water can contain asbestos fibers, and as evidence exists which shows increased risk of several malignancies from inhalation of these fibers, the aim of this review is to determine whether asbestos ingested with drinking water is harmful to health or not. After the examination of epidemiological studies, fiber absortion by intestinal walls, as well as World Health Organization Reports and Regulations and reports of different countries, it can be inferred that the state of the art does not allow to stablish: a) Evidence of a cause and effect relationship between asbestos ingestion and gastrointestinal cancer. b) Restricted limits of asbestos fibers in drinking water.

Abstract  Up-to-date information on scientific and technical achievements in use of asbestos and asbestos-free diaphragms and ion-exchange membranes in chlorine production industry hase been presented. Hazards connected with the use of asbestos have been discussed in the context of the legal ban on asbestos products use and the decree of the Minister of Economy on ways of their use and conditions of disposal. Methods of asbestos products disposal have been presented. Technical and economic conditions of the membrane electrolytic process of sodium chloride solution have also been discussed.

Abstract  The naming of asbestos as 'indestructible' or 'inextinguishable', as long ago as 50AD, was uniquely apt in defining the minerals future. Interestingly, even then the Roman Pliny, made a note that some slaves working in its environment developed respiratory problems. With the varied asbestos-cement combinations for the 20(th) and 21(st) Centuries there are existing challenges to be met, and always the possibility of exciting new developments. But this will only take place if there is a revived impetus in research particularly combing medical and scientific disciplines. Overall, this paper aims to promote discussion on how the legacy of asbestos impacts on future prospects.

Abstract  The fibrogenicity and carcinogenicity of asbestos fibers are dependent on several fiber parameters including fiber dimensions. Based on the WHO (World Health Organization) definition, the current regulations focalise on long asbestos fibers (LAF) (Length: L ≥ 5 μm, Diameter: D < 3 μm and L/D ratio > 3). However air samples contain short asbestos fibers (SAF) (L < 5 μm). In a recent study we found that several air samples collected in buildings with asbestos containing materials (ACM) were composed only of SAF, sometimes in a concentration of ≥10 fibers.L-1. This exhaustive review focuses on available information from peer-review publications on the size-dependent pathogenetic effects of asbestos fibers reported in experimental in vivo and in vitro studies. In the literature, the findings that SAF are less pathogenic than LAF are based on experiments where a cut-off of 5 μm was generally made to differentiate short from long asbestos fibers. Nevertheless, the value of 5 μm as the limit for length is not based on scientific evidence, but is a limit for comparative analyses. From this review, it is clear that the pathogenicity of SAF cannot be completely ruled out, especially in high exposure situations. Therefore, the presence of SAF in air samples appears as an indicator of the degradation of ACM and inclusion of their systematic search should be considered in the regulation. Measurement of these fibers in air samples will then make it possible to identify pollution and anticipate health risk.

Abstract  Data for the liquid sorption (Y) by asbestos membranes, coated with polyphenylene sulphide or with polyphenylene sulphide sulphonic acid and having variable polymer concentration (X) and acid equivalent (EW) values, have been fitted by multivariable mathematical models relating Y to X and EW in the bulk and in the surface membrane phase. The results point out that (i) the membrane surface is the sorption-limiting phase at low porosity, (ii) under this condition the liquid sorption selectivity depends on the membrane acid equivalent concentration, and (iii) the membrane acid functions allow both macro-permeation, into the bulk phase, and micro-permeation, through the coating layer into the asbestos support structure, of aqueous media.

Abstract  The generation and emission of particulate matter from abrasion industry are subjects of the pollution monitoring by multidisciplinary study involving earth sciences and engineering disciplines. This work investigates the correlation between textural properties of in situ rock with class size distribution and morphology of particles generated after rock comminution and particles emitted in the air. A special comminution-dust sampling architecture was realised. The combined use of scanning electron microscopy and particle size analyser was considered in performing digital image analysis on both crushed products and airborne particles collected onto membrane filters. The results show that the size and morphology of crushed particles are linked to the petrographic rock properties. In particular, particles with fibrous morphology are prominent in rocks showing foliated textures where elongated minerals occurred, with implication for asbestos-bearing rocks. For what concerns the airborne particles, the results show that their aerodynamic diameters are independent of the crusher operating conditions. External parameters probably intervene in the distribution of the airborne particles emission, including the dynamic air fluxes, or environmental conditions. By applying mathematical models, the morphology and size range of airborne particles following the comminution processes can be predicted, and results has implication for pollutants contamination due to particulate matters emitted by crush stone industry.