Man made mineral fibers

Stone wool fiber materials are commonly used for thermal and acoustic insulation, horticulture and filler purposes. Biosolubility of the stone wool fiber (SWF) materials accessed through acellular in vitro dissolution tests can potentially be used in future as an indicator of fiber biopersistence in vivo. To correlate acellular in vitro studies with in vivo and epidemiological investigations, not only a robust dissolution procedure is needed, but fundamental understanding of fiber behavior during sample preparation and dissolution is required...

Oceans are crucial to human survival, providing natural resources and most of the global oxygen supply, and are responsible for a large portion of worldwide economic development. Although it is widely considered a silent world, the sea is filled with natural sounds generated by marine life and geological processes. Man-made underwater sounds, such as active sonars, maritime traffic, and offshore oil and mineral exploration, have significantly affected underwater soundscapes and species. In this work, we report on a joint optical fiber-based communication and sensing technology aiming to reduce noise pollution in the sea while providing connectivity simultaneously with a variety of underwater applications...

Man-made vitreous fibers (MMVF) are a class of inorganic fibrous materials that include glass and mineral wools, continuous glass filaments, and refractory ceramic fibers valued for their insulative properties in high temperature applications. Potential health effects from occupational exposure to MMVF have been investigated since the 1970s, with focus on incidence of respiratory tract cancer among MMVF-exposed production workers. The general population may experience exposure to MMVF in residential and/or commercial buildings due to deterioration, construction, or other disruption of materials containing these fibers...

Biological materials such as nacre have evolved microstructural design principles that result in outstanding mechanical properties. While nacre's design concepts have led to bio-inspired materials with enhanced fracture toughness, the microstructural features underlying the remarkable damping properties of this biological material have not yet been fully explored in synthetic composites. Here, we study the damping behavior of nacre-like composites containing mineral bridges and platelet asperities as nanoscale structural features within its brick-and-mortar architecture...

BACKGROUND: Refractory Ceramic fibres (RCF) are man-made mineral fibres used in high performance thermal insulation applications. Analogous to asbestos fibres, RCF are respirable, show a pleural drift and can persist in human lung tissue for more than 20 years after exposure. Pleural changes such as localised or diffuse pleural thickening as well as pleural calcification were reported. RESULT: A 45 years old man worked in high performance thermal insulation applications using refractory ceramic fibres (RCF) for almost 20 years...

The biopersistence of fiber materials is one of the cornerstones in estimating potential risk to human health upon inhalation. To connect epidemiological and in vivo investigations with in vitro studies, reliable and robust methods of fiber biopersistence determination and understanding of fiber dissolution mechanism are required. We investigated dissolution properties of oil treated stone wool fibers with and without sugar-based binder (SBB) at 37 °C in the liquids representing macrophages intracellular conditions (pH 4...

Objective: To connect with the measurement data of asbestos dust fiber concentration in foreign countries, improve the accuracy of asbestos fiber detection in China, and understand the dust exposure in the working environment of asbestos and man-made mineral fiber production and processing sites in Zhejiang Province. The fiber count concentrations of working environment in glass fiber, ceramic fiber and asbestos processing plants were measured and compared. Methods: The dust concentration in the working environment of two glass fiber factories, one ceramic fiber factory and eight asbestos products processing factories was measured...

Airborne fibers are of public concern because of their potential threat to the environment, however their physical and chemical properties are poorly understood. Fibers are defined as having an aspect ratio >3:1. Fiber particles were collected in the near surface air, surface deposited dust and building materials in Beijing. They were examined using analytical scanning electron microscopy. The particles were initially classified into two categories: organic and inorganic. Organic fibers comprised microplastic and natural organic fiber particles...

Man-made mineral fibers (MMMFs) are substitutes for asbestos. MMMFs are widely used as insulation, but their molecular mechanisms underlying the tumorigenic effects in vivo have been poorly studied. For this reason, this work aimed to explore the properties and carcinogenic molecular mechanisms of MMMFs. The three MMMFs, rock wool (RW), glass fibers (GFs), and ceramic fibers (CFs), were prepared into respirable dust. Particle size, morphology, and chemical composition were analyzed by laser particle analyzer, scanning electron microscope, and X-ray fluorescence spectrometer, respectively...

The tooth enamel of vertebrates comprises a hyper-mineralized bioceramic, but is distinguished by an exceptional durability to resist impact and wear throughout the lifetime of organisms; however, enamels exhibit a low resistance to the initiation of large-scale cracks comparable to that of geological minerals based on fracture mechanics. Here we reveal that the tooth enamel, specifically from the giant panda, is capable of developing durability through counteracting the early stage of damage by partially recovering its innate geometry and structure at nano- to micro- length-scales autonomously...

Man-made mineral fibres (MMMFs) such as glass wool (GW), rock wool (RW) and refractory ceramic fibres (RCFs) are widely used as substitutes of asbestos. The present study aimed to investigate the cytotoxic effects on human bronchial epithelial cells (BEAS-2B) exposed to GW1, RW1 and RCF2, considering their properties similar to that of asbestos. We assessed cell viability; cell morphological changes; apoptotic rate; DNA damage; reactive oxygen species (ROS) generation; activities of caspase-3, caspase-8 and caspase-9; and expression levels of FasL, phosphorylated p38, and total p38 MAPK proteins...

Refractory ceramic fibers (RCFs) are amorphous fibers that belong to a class of materials termed synthetic vitreous fibers (SVFs), also called man-made mineral fibers (MMMFs), which includes alkaline earth silicate wool, glass wool, rock (stone) wool, slag wool, and special-purpose glass fibers. RCFs are more durable and biopersistent than several other SVFs, although very much less biopersistent than either amosite or crocidolite asbestos. Chronic inhalation studies indicated that rats and hamsters exposed to RCF fibers developed fibrosis and tumors...

Some mineral fibers represent a health hazard because they are classified as cancer-causing chemical/physical toxicants upon (chronic) dust inhalation. Although in the last decades they have been the subject of intensive multidisciplinary investigations, the mechanisms by which mineral fibers induce toxic and pathogenic adverse effects on human health and environment are not yet fully understood. The major intricacy of the biological approach that prevents the design of a conclusive shared model of behavior of mineral fibers in a biological system stems from their very nature with intrinsic variability in chemical, molecular, structural and morphometric parameters, biodurability and surface reactivity...

OBJECTIVE: To compare the determination methods of fiber number concentration between China and WHO. METHODS: Individual fiber samplings were conducted at a RCF manufacturing enterprise for 40 types of work. Flow rate was set as 2 L/min and lasted 2 to 4 hours. We used acetone-triacetin to prepare samples. The rules of two methods were used to count fibers for each sample respectively. The differences between the results of two methods were compared using the sign-rank test, and the correlation between the two methods' counting results were evaluated by the Spearsman rank correlation analysis...

OBJECTIVES: The aim of Evalutil is to document occupational exposure to asbestos and man-made mineral fibers. METHODS: These databases provide grouped descriptive and metrological data from observed situations of occupational exposure, collected through the analysis of scientific articles and technical reports by industrial hygienists. RESULTS: Over 5,000 measurements were collected. We describe the occupations, economic activities, fiber-containing products, and operations on them that have been documented most often...

PURPOSE OF REVIEW: Manufactured (artificial) fibers represent an important and continuously growing volume among substitutes to natural fibers. A major proportion of the population in an industrialized society has been, is, or will be in contact with these fibers. The fibrous configuration of asbestos is well recognized as being an important parameter in toxicity, and now that of synthetic fibers is also suspected of inducing serious health effects on the respiratory system. There is an ongoing debate about the actual fibrogenic effect of these man-made mineral fibers (MMMFs) in humans...

Many epidemiological studies, mostly with a case-control design, show an increased risk of cancer, in particular lung cancer, in construction workers. Asbestos is the occupational carcinogen considered for a long time the most important in this sector, but now it covers a residual role, at least in Italy. In this review the most recent studies are considered and the presence of other carcinogens, as crystalline silica, man-made mineral fibers, diesel exhausts, metals, solvents, UV rays, must be considered in risk evaluation also, possibly, for health and epidemiologic surveillance...

Man-made mineral fibers are produced using inorganic materials and are widely used as thermal and acoustic insulation. These basically include continuous fiberglass filaments, glass wool (fiberglass insulation), stone wool, slag wool and refractory ceramic fibers. Likewise, in the last two decades nanoscale fibers have also been developed, among these being carbon nanotubes with their high electrical conductivity, mechanical resistance and thermal stability. Both man-made mineral fibers and carbon nanotubes have properties that make them inhalable and potentially harmful, which have led to studies to assess their pathogenicity...

BACKGROUND: Occupational causes of respiratory cancers need to be further investigated: the role of occupational exposures in the aetiology of head and neck cancers remains largely unknown, and there are still substantial uncertainties for a number of suspected lung carcinogens. The main objective of the study is to examine occupational risk factors for lung and head and neck cancers. METHODS/DESIGN: ICARE is a multi-center, population-based case-control study, which included a group of 2926 lung cancer cases, a group of 2415 head and neck cancer cases, and a common control group of 3555 subjects...

OBJECTIVE: We aimed to fill in the gap of knowledge on the lung cancer burden resulting from occupational exposures among Chinese men through a population-based case-referent study. METHODS: Detailed information on lifestyle and full occupational histories of 1,208 male lung cancer incident cases and 1,069 age-matched male community referents were obtained through interviews during 2004-2006. The associations between lung cancer risk and exposures to specific or group of agents that were confirmed or suspected occupational carcinogens were analyzed...