Workers at the former Zonolite/W.R. Grace vermiculite processing plant in St. Louis, operating from the late 1940s to 1988, were exposed to asbestos from the processing and handling of asbestos-contaminated vermiculite and waste rock. This was the primary finding of the investigation that was documented in a report
In 2007, Spokane County developed a design and completed work on an asphalt and soil cap and cover over the southwest quadrant of the Site, where the former vermiculite processing and handling buildings were previously located, where the highest concentration of asbestos was found in soils, and where asbestos was found to occur at depth.
Libby vermiculite is referred to as "Libby asbestos" (LA). Studies throughout the 1980s indicated that workers exposed to vermiculite from Libby showed increased rates of asbestos-related respiratory diseases [2–7]. These findings from Libby and from other sites that processed vermiculite from Libby provided the impetus for investigating the
Objective: To examine the relationship between cumulative fiber exposure (CFE) and mortality in a retrospective cohort study of vermiculite workers exposed to Libby amphibole (n = 1862). Methods: Extended Cox regression was used to estimate the hazards associated with CFE as a time-dependent covariate of multiple-cause mortality. Results: The Cox models for mesothelioma, asbestosis, lung ...
The risk of developing these diseases depends upon many factors, including the chemistry and shape of the fiber, level of exposure, duration of exposure, the individual''s physiological response to fiber exposure, and the smoking history of the exposed individual.11 Vermiculite Processing Vermiculite is produced from ore mined throughout the world.
South Carolina is the largest producer of vermiculite in the United States, which poses a threat to state residents. Although the mineral is not dangerous, vermiculite ore often contains large amounts of asbestos. People who worked at or lived near vermiculite mines or vermiculite processing facilities may have been exposed to asbestos.
· Workers in and around the Libby mine developed serious health problems. Like any hazards, length and intensity of exposure are major factors in the risk of asbestos-related respiratory illness. To assess the risk of asbestos exposure at a house, a sample of the vermiculite would need to be analyzed by a lab.
for stockpiling, staging and distributing vermiculite and vermiculite concentrate to vermiculite processing areas and insulation distributors outside of Libby. EPA''s work in Libby began when the Agency sent an Emergency Response Team to investigate local concerns about asbestos-contaminated vermiculite in 1999. Since then, EPA has been working
Workers employed at Vermiculite Northwest during 1967 until 1994 were exposed to elevated levels of Libby asbestos as a result of working in and around the facility. ... processing plant closed may have been exposed to asbestos. The soil near the railroad tracks east of …
A major public health crisis was recognized when asbestos-contaminated vermiculite ore mined near Libby, Montana was found to be affecting workers, causing an excess of lung cancer deaths, non ...
If you choose to remove the vermiculite insulation, this work should be done by a trained and ... the manufacture, importation, processing, or distribution in commerce for most of the asbestos-containing product categories originally covered in the 1989 final rule was overturned. Only the
a very small number of processing plant workers who worked with the crude ore every day for years and years. Among people who were exposed to or worked with only the expanded, processed vermiculite, we don''t know of any one who has become sick or developed asbestosis or mesothelioma from exposure to Libby, Montana vermiculite.
Mining vermiculite deposits in South Carolina presented its own hazards, but the state also received shipments of asbestos-contaminated vermiculite from Libby, Montana. South Carolina is the largest producer of vermiculite in the country. Workers at the vermiculite mines and vermiculite processing facilities were likely exposed to asbestos.
into bags held by workers at the end of a chute. The resulting product was a lightweight material ideal for insulation and other products. Processing vermiculite was an extremely dusty task; so workers were exposed to high levels of dust that contained asbestos. What has been done to determine if the site poses a health threat?
South Africa Vermiculite Processing Plant. According to different production requirements, product specifications of vermiculite are as follows:8-12MM,4-8MM,2-4MM,1-2MM,0.3-1MM,40-60 mesh,60-80 mesh,80-100 mesh, 100 mesh, 150 mesh, 200 mesh, 325 mesh, etc. With the development of vermiculite''s applications, South African abundant ...
The name vermiculite comes from the Latin "vermiculus," meaning larva or small and worm-like, or "vermiculare," meaning to breed worms, for its characteristic look when undergoing exfoliation. Prior to Thomas H. Webb''s work in the early 19th century, vermiculite was known for many years in Japan as a children''s novelty.
In a later study by Lockey et al. (1984), workers exposed to vermiculite contaminated with fibrous tremolite were examined. A total of 530 employees, in a plant processing vermiculite ore to its expanded form were studied. Industrial hygiene sampling of airborne fibers was initiated in 1972, 15 years after the plant had begun using vermiculite.
Vermiculite insulation exposure levels in residential buildings: What are reasonable risk assessments for people exposed to vermiculite insulation in residential buildings. Most research on health hazards from asbestos-containing vermiculite insulation has focused on workers at vermiculite mining or processing sites or at communities close to those locations.
from vermiculite processing, and workers did not remove vermiculite materials from the site for personal use. Could I have been exposed to asbestos from this site in the past? You were probably exposed to asbestos from this site if you: • Worked at this facility when it processed vermiculite, or • Lived with someone who worked at the ...
Vermiculite is not asbestos and is a safe, highly versatile mineral used widely through the world in many products. For more information, contact The Vermiculite Association at 717-238-9902 or via email to [email protected] . Title: Microsoft Word - FAQ-FINAL VERSION - August 2015
· Take a rough estimate of the 25% mark, and then pour in the soil on top of the vermiculite. Work the soil and the vermiculite together using your hands, ensuring that you get an even distribution of the two materials. Don''t worry about getting the vermiculite on your hands, it''s sterile and non-toxic, even if it looks strange. ...
· In South Carolina, vermiculite ore, which contains asbestos, is part of the mining industry, and workers still face exposure to asbestos at the state''s coastal shipyards. ... But it used to be a series of processing plants that exposed workers to asbestos.
11.28 Vermiculite Processing 11.28.1 Process Description1-9 Vermiculite is the geological name given to a group of hydrated laminar minerals that are aluminum-iron-magnesium silicates and that resemble mica in appearance. The chemical formula for vermiculite is (Mg,Ca,K,Fe+2) (Si,Al,Fe+3) O (OH) 4H O. When subjected to heat, vermiculite has 3 4 ...
· 2. Obtaining vermiculite small particles. Natural vermiculite flakes are characterized by high values of aspect ratio. In clay science, exfoliation involves a degree of separation of the layers of a host structure where units, either individual layers or stacking of several layers, are dispersed (freely oriented and independent) in a solvent or polymer matrix .
· Vermiculite is used in the garden or potting soil to help aerate the soil and increase water and nutrient retention. Vermiculite is an excellent choice for amending the soil of moisture loving plants because of its water retention properties. It is also useful for encouraging faster root growth in cuttings. One of the benefits of horticultural ...
A.L. Bush, in Encyclopedia of Materials: Science and Technology, 2001 2.2 Vermiculite. Vermiculite is a mica, a hydrated, magnesium–iron–aluminum trioctahedral sheet silicate of varied composition. Its basic unit is two tetrahedral silicate sheets interlayered by an octahedral sheet that contains aluminum and iron (Grim 1962).Each tripartite layer, on its upper and lower surfaces, has ...
Vermiculite Northwest, Inc. and later by W.R. Grace and Company. Vermiculite ore from Libby, Montana, was received at the property. The ore contained asbestos. Records show that up to 10,317 tons of vermiculite ore was processed at the facility from January 1967 to October 1970.
Vermiculite is normally a platey mineral in its natural state. Processing of the ore can sometimes lead to the peeling off or "scrolling" of the surface layers at the edges of crystals forming fibres (Chatfield and Lewis 1980). Parallel fracturing and splitting of vermiculite flakes can also lead to the formation of fibre-shaped fragments.
from the vermiculite processing facilities located in Salt Lake City was not likely to be a significant contributing factor to the increased rates observed in other asbestos related cancers and diseases in the two-mile radius analysis area. However, asbestosis-related mortality is almost always found in workers with very high long-term exposure.
· Like perlite, vermiculite is an effective soil conditioner that can loosen compacted soil, provide drainage, and hold three to four times its weight in water. But—and this is an important but —vermiculite is more compressible and less porous than perlite, giving vermiculite higher water-holding capacity when it''s used as a planting medium.
· A major public health crisis was recognized when asbestos-contaminated vermiculite ore mined near Libby, Montana was found to be affecting workers, causing an …
· Vermiculite Processing Operations in Northeast Minneapolis. Vermiculite ore containing hazardous Libby asbestos was processed in Northeast Minneapolis from 1938-1989. This page contains information about the vermiculite, ways people were exposed, potential health impacts, and publications and resources.
final work. DRAFT AP-42 SECTION . 11.28 11.28 . VERMICULITE PROCESSING . 11.28.1 . Process Description''-g Vermiculite is the geological name given to a group of hydrated laminar minerals that are aluminum-iron-magnesium silicates and that resemble mica in appearance. The chemical formula for vermiculite is (Mg,Ca,K,Fe+2),(Si,A1,Fe+3)40,0(OH)2*4H20.
· Asbestos dust had already caused lung diseases and deaths among vermiculite miners and processing plant workers, but the company''s executives hid this information. They continued growing the Zonolite business throughout the 1970s, even as more employees and residents of the town fell ill from asbestos exposure.
· The company operated a processing plant in Libby and shipped contaminated ore to 244 sites throughout the U.S., and at least 28 of these sites were processing plants. Even though these were not pure asbestos plants, workers developed asbestos-related diseases because the vermiculite ore contained approximately 20% asbestos.