Asbestos Release Research Articles

Comparison of the effects of use, protection, improper renovation and removal of asbestos products on the example of typical old office buildings in Poland

The study focused on old, German building types “LIPSK” and “BERLIN” used in Poland, since the 1960s in Eastern Europe. The different operations on buildings were analysed: protection and maintenance of asbestos products, asbestos removal and inadvertent damage to asbestos as a result of building renovation. Measurements of respirable (countable) asbestos fibres in the air were carried out using the PCOM + PLM method and SEM–EDS. In the case of the accidental destruction of products, initial contamination was ≈7000 f/m3. After 16 weeks from the end of the activity and 20 days of extreme ventilation, contamination decreased to about 500 f/m3. At the same time, in similar rooms, without extreme ventilation, the pollution was above 4000 f/m3. The average increase in pollution in a dozen or so similar buildings, after asbestos removal in places beyond the work zones, ranged from ≈ 1700–2700 f/m3 and lasted for one or two years. These buildings, used without ACM destruction or after product impregnation, have maintained low asbestos contamination < 300 f/m3 for more than 10–20 years. So, due to the easy release of asbestos that occurs with any ACM removal and the increased risk of occupant exposure, these works are often inappropriate for the buildings in question.

Airborne Asbestos Fiber Concentration in Buildings: Surveys Carried Out in Latium (Central Italy)

In Italy, use and production of asbestos and asbestos-containing materials (ACMs) were banned in 1992, however, the risk of exposure to asbestos still exists, because most ACMs are located in industrial and public buildings. A total of 111 Italian buildings with friable and non-friable ACMs were surveyed; 500 air samples were collected in the areas where contamination might have occurred. Airborne asbestos fiber concentration calculated from air samples was averaged for each building. Statistical analysis of the data showed no significant differences between the mean concentration measured in buildings with friable and non-friable ACMs (p = 0.258). The concentration values were below 2 f/L, the value stated by Italian regulation to ensure that the area is safe to reoccupy after asbestos removal. Samples of settled dust were also collected. The presence of asbestos fibers in the dust showed the occurrence of a release of asbestos from the material. Although the airborne asbestos fiber concentrations measured were low, current Italian regulation requires an asbestos management program. The Public Institution to which the authors of this work belong encourages asbestos removal as the preferred abatement method, in line with the asbestos-free future approach proposed by the European Commission.

Asbestos Release from Whole-Building Demolition of Buildings with Asbestos-Containing Material

The whole-building demolition method, which entails one-or two-story buildings pushed down by heavy equipment, loaded into trucks, and hauled away, is generally the most cost-effective means to remove small buildings. For taller buildings, a crane and wrecking ball may be used initially to reduce the height of the building. Demolitions might release asbestos fibers from friable asbestos-containing material (ACM). Fibers also might be released from nominally nonfriable ACM (Categories I and II nonfriable ACM) if it becomes friable after rough handling throughout the whole-building demolition process. This paper reports on asbestos air monitoring from two demolition projects involving ACM. In one building, Category II nonfriable ACM was present because it could not be removed safely prior to demolition. Both projects had large quantities of gypsum wallboard with ACM joint compound and ACM flooring. One building had large quantities of ACM spray-on ceiling material. During the demolitions personal air monitoring of the workers and area air monitoring downwind and around the sites were conducted. The monitoring found the concentrations of fibers detected by phase contrast microscopy were generally well below the permissible exposure limits (PEL) of workers. Electron microcopy analysis of samples at or near the PEL indicated most of the fibers were not asbestos, and the actual asbestos exposure was often below the detection limit of the procedure. The buildings were kept wet with fire hoses during the demolition and that required large quantities of water, 20,000–60,000 gal/day (75–225 m3/day). Earlier studies found little asbestos release from buildings containing only nonfriable ACM demolished by this method. This project found a negligible release of asbestos fibers, despite the presence of nonfriable materials that might become friable, such as ACM joint compound and spray-on ACM ceiling coating.

Simulation Tests to Assess Occupational Exposure to Airborne Asbestos from Asphalt-Based Roofing Products

This study sought to evaluate exposure from specific products to evaluate potential risk from roof repair activities. Five asbestos-containing fibered roof coatings and plastic cements, representing a broad range of these types of products, were tested in exposure simulations. These products were applied to representative roof substrates. Release of asbestos fibers during application and sanding of the product shortly thereafter (wet sanding) were tested initially. Other roof substrates were cured to simulate a product that had been on a rooftop for several months and then were tested to evaluate release of fibers during hand sanding and hand scraping activities. Additional tests were also conducted to evaluate asbestos release during product removal from tools and clothing. Two personal (n = 84) and background/clearance (n = 49) samples were collected during each 30-min test and analyzed for total fiber concentration [phase-contrast microscopy (PCM)] and for asbestos fiber count [transmission electron microscopy (TEM)]. PCM concentrations ranged from <0.005 to 0.032 fibers per cubic centimeter (f cc(-1)). Chrysotile fibers were detected in 28 of 84 personal samples collected. TEM concentrations ranged from <0.0021 to 0.056 f cc(-1). Calculated 8-h time-weighted averages (TWAs) ranged from 0.0003 to 0.002 f cc(-1) and were comparable to the background TWA concentration of 0.0002 f cc(-1) measured in this study. Based on these results, it is unlikely that roofers were exposed to airborne asbestos concentrations above the current or historical occupational guidelines during scraping and sanding of these products during roof repair.

Asbestos release during removal of resilient floor covering materials by recommended work practices of the resilient floor covering institute.

The release of asbestos during maintenance and removal of resilient floor covering is of concern to health professionals and many regulators. This study assesses the asbestos levels observed during removal of resilient floor covering products using the "Recommended Work Practices" (1995) of the Resilient Floor Covering Institute or other methods requiring containment (Controls). The 1995 "work practices" require wet removal or dry heat removal but do not require the use of respirators. Wet removals of sheet vinyl/separated backing, 12" x 12" vinyl asbestos tile/mastic, and 9" x 9" asphalt tiles/mastic were conducted and the air was sampled during each procedure. Settled dust samples were collected at the sites of RFCI square tile removal and pieces of each type of tile were broken in a mini-enclosure to evaluate asbestos emissions. Analyses of the air samples collected during the removals showed that the RFCI methods did not produce asbestos counts significantly different from the Control methods requiring containment. Only a small number (0.7%) of fibers and structures, counted and measured by Analytical Transmission Electron Microscopy, would have been counted using the rules for Phase Contrast Microscopy in the 7400 method specified by Occupational Safety and Health Administration regulations. This indicates workers in similar situations without respirators are likely to have unknown exposure levels. A high percentage of these fibers and structures are 5 micrometers or less in length, smaller than 0.5 micrometer in diameter, and are easily inhaled. The RFCI air sample and settled dust data may cause regulators to consider requiring respiratory protection, cleanup procedures, and methods to control asbestos migration. Other areas that might be addressed are clearance levels and their measurement, removal area size, bulk sample analysis by transmission electron microscopy if polarized light microscopy reports less than 1 percent asbestos, better worker exposure evaluation, and supervisor/worker training in accordance with the Model Accreditation Plan.

Asbestos Release During Removal of Resilient Floor Covering Materials by Recommended Work Practices of the Resilient Floor Covering Institute

Asbestos Release During Removal of Resilient Floor Covering Materials by Recommended Work Practices of the Resilient Floor Covering Institute

Asbestos Operation and Maintenance Studies on Carpet Cleaning, High Efficiency Particulate Air Vacuum Use, and Tile Buffing

Abstract The U.S. Environmental Protection Agency's Risk Reduction Engineering Laboratory has conducted several research studies on the effectiveness of control measures for operation and maintenance activities in asbestos-contaminated buildings. Studies have been conducted on carpet cleaning, bag changing activities of portable high efficiency particulate air (HEPA) filter vacuums, and vinyl asbestos floor tile maintenance practices. In the carpet cleaning studies, hot water cleaning, HEPA vacuuming, and conventional vacuuming were compared. All three processes resulted in the release of asbestos into the surrounding environment as measured by transmission electron microscopy (TEM); however, none of the worker levels exceeded the Occupational Safety and Health Administration (OSHA) standard as measured by phase contrast microscopy (PCM). In the HEPA vacuum bag changing evaluation, all units tested exposed the worker to elevated asbestos concentrations, emphasizing the prudence of using protective clothin...

Asbestos Release from the Demolition of Two Schools in Fairbanks, Alaska

Abstract Two elementary schools on Fort Wainwright Army Base in Fairbanks, Alaska, were demolished during the Summer of 1992. Prior to demolition, all friable asbestos was removed from the buildings in accordance with the applicable Environmental Protection Agency's asbestos National Emission Standard for Hazardous Air Pollutants. The primary objective of the study was to assess whether the demolition of the buildings with Category 1 materials (floor tile and roofing materials) in place (as was the case in Fairbanks) resulted in a downwind increase in the airborne asbestos concentration. The secondary objective was to document the worker exposure levels encountered by the demolition workers and the workers transporting the debris. Area sampling was conducted upwind and downwind of the demolition sites and at the landfill, with sample analysis by transmission electron microscopy. Personal sampling of workers was conducted using the standard Occupational Safety and Health Administration (OSHA) methods, with...

Early-passage rat lung fibroblasts do not migrate in vitro to transforming growth factor-beta.

Lung fibrosis has been postulated to be mediated by the production of macrophage-derived growth factors that are both mitogenic and chemotactic for fibroblasts. In vitro studies from our laboratory demonstrated that alveolar and interstitial macrophages treated with iron and asbestos release platelet-derived growth factor (PDGF) and transforming growth factor-beta (TGF-beta) into the media. This conditioned media was capable of inducing proliferation and chemotaxis of primary rat lung fibroblasts (RLF). TGF-beta is known to be present in the media, and RLF have high-affinity receptors for TGF-beta. However, we found that > 95% of the chemotaxis was blocked by a polyclonal anti-PDGF antibody, whereas anti-TGF-beta did not change cell migration. TGF-beta has been described previously as a potent chemoattractant for fibroblasts. Thus, we tested the potential of purified TGF-beta to induce RLF chemotaxis in an attempt to address this apparent contradiction in results. Four separate preparations of RLFs from four different rats, Swiss 3T3 cells, human and rat fetal skin fibroblasts, and human foreskin fibroblasts were tested for chemotaxis using purified porcine TGF-beta 1 as well as human TGF-beta. None of these cells responded chemotactically to TGF-beta over a broad range of concentrations used (0.004 pg/ml to 50 ng/ml). RLF plated at different densities also did not respond to TGF-beta. On the other hand, all the fibroblast types migrated vigorously to PDGF (4 ng/ml).(ABSTRACT TRUNCATED AT 250 WORDS)

Pleural mesothelial cells stimulated by asbestos release chemotactic activity for neutrophils in vitro.

The development of the pleural inflammatory response to asbestos remains poorly defined. Importantly, the role of the pleural mesothelial cell in recruitment of neutrophils to the pleural space is not known. We hypothesized that rabbit pleural mesothelial cells stimulated by asbestos fibers release chemotactic factor(s) for neutrophils. Primary cultures of rabbit pleural mesothelial cells were established, and their purity verified by the presence of keratin and hyaluronic acid mucin. Mesothelial cells in serum-free media, in the presence of 30 micrograms/ml of crocidolite asbestos, released chemotaxins for neutrophils. This activity was not dependent on the type of asbestos fiber or fiber length. It was dose-dependent until 30 micrograms/ml of asbestos. The chemotactic fractions had the ability to increase both directed and random migration of neutrophils. The chemotactic activity was not present in sonicated fractions of unstimulated mesothelial cells, nor in supernates of asbestos fibers alone. Characterization of the chemotactic activity showed that it was heat stable (56 degrees C per 30 min) and sensitive to digestion with trypsin and papain. On Sephadex G-50 chromatography, it had a molecular weight between 6,000 and 9,000. Production of the chemotactic activity was inhibitable by cycloheximide. These results demonstrate that pleural mesothelial cells can actively synthesize a protein fraction with chemotactic activity for neutrophils. Production of this mesothelial cell-derived chemotactic activity for neutrophils may play an important role in the initiation of the inflammatory response of the pleura to asbestos.

The release of asbestos fibers from vinyl-asbestos floor tiles

There have been extensive studies of the release of asbestos fibers from friable materials used for construction. To date very little is known about the release of asbestos fibers from materials we assume to be non-friable. Since one of the major uses of asbestos was in the manufacture of floor tiles, and flooring is scoured prior to applying sealants, we have studied the release of asbestos from tiles treated in ways which model the processes tiles would be subjected to over their time of use.Vinyl-asbestos tiles were gathered and assayed for their asbestos content by TEM and polarized light microscopy (PLM). Containments were set up and the following experiments performed: 1. 9 inch square tiles were drilled 10 times with a 3/4 inch drill 2. tiles were drilled once with the drill bit above 3. tiles were boken into 1 1/2 inch pieces 4. tiles were broken into 4 pieces 5. tiles were stripped, and then coated with sealants prior to further scrubbing.

REBUTTAL—Consumer product safety: risk assessment of exposure to asbestos emissions from hand-held hair dryers

The United States Consumer Product Safety Commission (CPSC) is concerned that consumer exposure to asbestos from consumer products may present an unreasonable risk of injury. Recently, CPSC has obtained agreement by industry to cease production and distribution of hair dryers containing asbestos heat insulation. CPSC intends to broaden its investigation by selecting consumer products containing asbestos for “priority attention.” The Commission does not intend to make quantitative estimates of cancer risks posed by exposure to asbestos fibers in making regulatory decisions. This position may lead to a serious waste of resources for the Commission, industry, and society. The Commission should focus its initial attention on those products for which the release of asbestos is significant enough to cause an unreasonable health risk. To make a risk assessment for a particular use of asbestos, CPSC must acquire or request data on asbestos emissions and define “unreasonable risk to health.”

Asbestos release from battery boxes.

Asbestos Release from Battery Boxes Get access M. Greenberg M. Greenberg HM Medical Inspector of Factories HM Factory Inspectorate, Department of Employment and Productivity1-13 Chepstow Place, London, W.1. Search for other works by this author on: Oxford Academic PubMed Google Scholar The Annals of Occupational Hygiene, Volume 13, Issue 1, January 1970, Pages 79–80, https://doi.org/10.1093/annhyg/13.1.79 Published: 01 January 1970