Asbestos Research Research Articles

Assessment of Optical and Scanning Electron Microscopies for the Identification and Quantification of Asbestos Fibers and Typical Asbestos Bodies in Human Colorectal Cancer Tissues

Asbestos research, identification, and quantification have been performed over the years, and the relationship between fiber inhalation and lung disease development is well defined. The same cannot be said for the gastroenteric system: the International Agency for Research on Cancer (IARC) believes that colorectal cancer (CRC) could be associated with asbestos exposure, but research has not demonstrated a casual nexus between exposure and CRC, despite highlighting an association tendency. The combination of scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) is the most applied technique in asbestos fiber identification in tissues and intestinal mucosa. In this study, SEM/EDS was applied to evaluate the presence of asbestos fibers and bodies (ABs) inside the tissue of eleven patients affected by CRC who had undergone environmental exposure due to living in an asbestos-polluted area where an Eternit plant had been active in the past. This technique was coupled with optical microscopy (OM) to verify whether the latter could be applied to evaluate the presence of these mineral phases, with the goal of understanding its suitability for identifying fibers and ABs in colon tissues. In addition to verifying the presence of fibers, this study allowed us to identify the deposition site of said fibers within the sample and possibly detect associated tissue reactions using OM, over a shorter time and at lower costs. Despite being a preliminary and descriptive work, the obtained results allowed us to propose a method involving first-sample OM observation to identify regulated (fibers with a length ≥ 5 μm, a thickness ≤ 3 μm, and a length/thickness ratio > 3) asbestos phases and ABs in the extra-respiratory system. In fact, OM and SEM/EDS provided similar information: no asbestiform morphology or ABs were found, but phyllosilicates and other inorganic materials were identified. This research needs to be continued using higher-resolution techniques to definitively rule out the presence of these fibers inside tissues whilst also increasing the number of patients involved.

Current Research and Opportunities to Address Environmental Asbestos Exposures.

SummaryAsbestos-related diseases continue to result in approximately 120,000 deaths every year in the United States and worldwide. Although extensive research has been conducted on health effects of occupational exposures to asbestos, many issues related to environmental asbestos exposures remain unresolved. For example, environmental asbestos exposures associated with a former mine in Libby, Montana, have resulted in high rates of nonoccupational asbestos-related disease. Additionally, other areas with naturally occurring asbestos deposits near communities in the United States and overseas are undergoing investigations to assess exposures and potential health risks. Some of the latest public health, epidemiological, and basic research findings were presented at a workshop on asbestos at the 2014 annual meeting of the Society of Toxicology in Phoenix, Arizona. The following focus areas were discussed: a) mechanisms resulting in fibrosis and/or tumor development; b) relative toxicity of different forms of asbestos and other hazardous elongated mineral particles (EMPs); c) proper dose metrics (e.g., mass, fiber number, or surface area of fibers) when interpreting asbestos toxicity; d) asbestos exposure to susceptible populations; and e) using toxicological findings for risk assessment and remediation efforts. The workshop also featured asbestos research supported by the National Institute of Environmental Health Sciences, the Agency for Toxic Substances and Disease Registry, and the U.S. Environmental Protection Agency. Better protection of individuals from asbestos-related health effects will require stimulation of new multidisciplinary research to further our understanding of what constitutes hazardous exposures and risk factors associated with toxicity of asbestos and other hazardous EMPs (e.g., nanomaterials).

Temporal trend, geographic distribution, and publication quality in asbestos research.

Asbestos is a well-known cause of cancer and respiratory diseases. The aim of the current study was to investigate the scientific production in asbestos research evaluating temporal trend, geographic distribution, impact factor (IF) of published literature, and taking into account socioeconomic variables. The PubMed database was searched starting from 1970. Publication numbers and IF were evaluated as absolute values and after standardization by population and gross domestic product (GDP). Six thousand nine hundred seven articles related to asbestos were retrieved. Publications grew steeply in the 1970s, leveled off in the 1980s, decreased in the 1990s, and then increased again. Mesothelioma, lung neoplasms, and occupational diseases are the most commonly used keywords. In the period of 1988-2011, 4220 citations were retrieved, 3187 of whom had an impact factor. The US, Italy, and the UK were the most productive countries. European countries published about 20 % more asbestos-related articles than the US, although the latter reached a higher mean IF, ranking second after Australia. When the national scientific production (sum of IF) was compared taking into account socioeconomic variables, Australia and Scandinavian countries performed very well, opposite to all main asbestos producers like Russia, China, and Brazil (except for Canada). The American Journal of Industrial Medicine and the Italian La Medicina del Lavoro published the highest numbers of articles. This study provides the first bibliometric analysis of scientific production in asbestos research. Interest appears to be higher in selected countries, with strong national features, and is growing again in the new millennium.

102 Occupational asbestos exposure and risk of pleural mesothelioma, lung and laryngeal cancer in the prospective Netherlands Cohort Study

ObjectivesAlthough asbestos research has been ongoing for decades, there are remaining questions regarding cancer risk associated with low exposure and cancer subtypes, the influence of potential confounders, and the interaction...

Multiple Modes of Action of Asbestos and Related Mineral Fibers

“Asbestos” is a generic term that encompasses multiple fiber types but may mean different things, depending on the scientific discipline. This lack of consistency among asbestos research communities can lead to a disconnect when comparing studies in asbestos research. Differences in the interpretation of asbestos definitions between disciplines lead to discrepancies in the results and their interpretations from the research analyzed. A comparison of the health and environmental impacts of various asbestos fibers is not possible without consistency in how these fibers are defined. A grasp of these issues is important to fully understand the state of the science of asbestos research. A respirable environmental dust like asbestos may work through more than one mode of action (MOA), with multiple MOAs for various health outcomes following exposure to the same particulate (e.g., interstitial fibrosis versus lung cancer versus mesothelioma). A mode of action encompasses a sequence of key events and processes that begin with the interaction between fibers and cells that may result in both cancer and complex noncancer health effects. The complexities of fiber toxicity make it difficult to define one MOA for asbestos in general. Further, the potential overlap of multiple MOAs makes it feasible to assume

Applying Definitions of “Asbestos” to Environmental and “Low-Dose” Exposure Levels and Health Effects, Particularly Malignant Mesothelioma

Although asbestos research has been ongoing for decades, this increased knowledge has not led to consensus in many areas of the field. Two such areas of controversy include the specific definitions of asbestos, and limitations in understanding exposure-response relationships for various asbestos types and exposure levels and disease. This document reviews the current regulatory and mineralogical definitions and how variability in these definitions has led to difficulties in the discussion and comparison of both experimental laboratory and human epidemiological studies for asbestos. This review also examines the issues of exposure measurement in both animal and human studies, and discusses the impact of these issues on determination of cause for asbestos-related diseases. Limitations include the lack of detailed characterization and limited quantification of the fibers in most studies. Associated data gaps and research needs are also enumerated in this review.

Obituary: Dr John MG Davis PhD, DSc, FRCPath

Obituary: Dr John MG Davis PhD, DSc, FRCPath

Analysis of Asbestos Research Conducted in Japan

Analysis of Asbestos Research Conducted in Japan

Directions and Needs in Asbestos Research: New Insights: Conference Summary

The Center for Environmental Health Sciences (CEHS) Conference, entitled “Directions and Needs in Asbestos Research: New Insights,” was held at the University of Montana in Missoula. Researchers, physicians, health care workers, and federal agency representatives from around the country met for a cross-disciplinary exploration of many issues related to asbestos research. Topics included community and psychosocial issues in biomedical research, asbestos exposure assessment, assessment and mechanisms of asbestos related diseases, and new research directions. This meeting report is a summary of the conference presentations, and of the topics identified for future research directions. This conference was a follow-up to one hosted by the CEHS in June 2002, and continued to take advantage of opportunities to work with a unique population in Libby MT, where significant asbestos exposures have occurred due to the mining of asbestos-contaminated vermiculite. The goals of this conference were to bring together experts from diverse fields to identify progress made since the last conference and to develop new research avenues that would allow us to address the research needs in emerging asbestos-exposed populations. Participants indicated that these objectives were met, and expressed enthusiasm for follow-up conferences to maintain the dialog that has been established regarding directions and needs in asbestos research. Selected papers from the conference are presented here.

Eighth International Mesothelioma Interest Group

The eighth International Mesothelioma Interest Group (IMIG) meeting was held in Chicago, IL, United States, in 19-22 October 2006 to discuss mesothelioma - the cancer often linked to asbestos exposure. It is a very aggressive malignancy with a median survival of less than 1 year from diagnosis. Millions of people have been exposed worldwide to asbestos, especially during the second half of the twentieth century when asbestos use increased significantly. The tons of asbestos utilized in the past remain a health hazard for current and future generations because asbestos is difficult to be disposed off. This makes asbestos and mesothelioma research a public health issue in addition to a medical problem. Moreover, the very high costs of asbestos litigation have a significant impact on the whole economy. In the United States, up until 2001, defendant companies had paid 54 billion dollars in claims and estimated future liabilities ranged from 145 to 210 billion. Therefore, asbestos research is of great interest to a large audience that includes patients, millions of asbestos-exposed individuals, scientists, physicians, public health officials, politicians, unions of asbestos workers, lawyers and the public at large. During the past few years, there has been significant progress in understanding the process of mineral fiber carcinogenesis and mesothelioma pathogenesis. With improved understanding of the pathogenesis of mesothelioma, new diagnostic, preventive and therapeutic options are being developed. A total of 247 papers were presented at the IMIG: the abstracts of these presentations were published in Lung Cancer, Supplement 1, October 2006. Here, experts in different disciplines critically review some of the most exciting presentations of the IMIG meeting. The result is a comprehensive review of the research field of asbestos carcinogenesis and mesothelioma, and of the progress that has been made in recent years in both basic and clinical sciences.

Conference Summary. Directions and Needs in Asbestos Research: New Insights

The Center for Environmental Health Sciences (CEHS) Conference entitled “Directions and Needs in Asbestos Research: New Insights” was held at the University of Montana in Missoula on July 28 and 29, 2005. Researchers, physicians, health care workers, and federal agency representatives from around the country met for a cross-disciplinary exploration of many issues related to asbestos research. Topics included community and psychosocial issues in biomedical research, asbestos exposure assessment, assessment and mechanisms of asbestos-related diseases, and new research directions. This meeting report is a summary of the conference presentations, and of the topics identified for future research directions. This conference was a follow-up to one hosted by the CEHS in June 2002, and continued to take advantage of opportunities to work with a unique population in Libby, MT, where significant asbestos exposures have occurred due to the mining of asbestos-contaminated vermiculite. The goals of this conference were to bring together experts from diverse fields to identify progress made since the last conference and to develop new research avenues that would allow us to address the research needs in emerging asbestos-exposed populations. Participants indicated that these objectives were met, and expressed enthusiasm for follow-up conferences, tentatively planned for the summer of 2007, to maintain the dialog that has been established regarding directions and needs in asbestos research. Selected papers from the conference are presented in this issue of Inhalation Toxicology.

Area and personal airborne exposure during abatement of asbestos-containing roofing material.

Exposure to asbestos-containing material (ACM) is considered to be hazardous and can result in various occupationally related diseases (Health Effects Institute Asbestos Research HEI, 1991). This has resulted in establishment of regulations to protect those associated with this industry (Lange et al. 1996, Lange and Thomulka, 1995), although it has also been claimed that such abatement regulations are a public policy disaster in the US (Ross, 1995). The United States Occupational Safety and Health Administration (OSHA) has published regulatory standards for abatement of asbestos-containing roofing material (ACRM) and these requirements have been described in a Settlement Agreement with the roofing industry (OSHA, 1995). Under item 9 paragraph 1101(f)(2)(ii) as codified in 29 C.F.R. initial exposure monitoring is not required if a negative exposure assessment has been prepared (OSHA, 1995). Negative assessment by its self does not eliminate future air monitoring, but does allow an employer to consider that work activities of a same nature result in similar exposure levels (Lange et al. 1996). If such a negative assessment suggests exposure is below the OSHA permissible exposure limit (PEL), which is 0.1 fibers per cubic centimeter (f/cc) timeweighted average (TWA) (OSHA, 1995) many of the practices involving personal protection can be minimized. The most commonly referenced requirement involving personal protection is employment of a respirator (Lange et al. 1996). Thus, information about historical exposure levels can result in cost savings for those involved with abatement of ACRM (Lange et al. 1996). Currently there are few published studies of airborne exposure from asbestos during abatement (HEI, 1991; Lange et al. 1996; Lange and Thomulka, 1999) particularly roofing materials. Publishing exposure data can assist those in the abatement field in establishing historical information on exposure (Lange et al. 1996). This will allow development of a database for anticipated exposure during abatement of various materials and with different work practices (HEI, 1991).

Corruption of previously published asbestos research.

Corruption of previously published asbestos research.

Workshop report

Workshop report

Asbestos exposures in public and commercial buildings

American Journal of Industrial MedicineVolume 27, Issue 3 p. 433-437 Commentary Asbestos exposures in public and commercial buildings Arthur C. Upton MD, Arthur C. Upton MD Health Effects Institute—Asbestos Research, Cambridge, MASearch for more papers by this authorDr. Rashid A. Shaikh PhD, Corresponding Author Dr. Rashid A. Shaikh PhD Health Effects Institute—Asbestos Research, Cambridge, MAHealth Effects Institute-Asbestos Research, 141 Portland Street, Cambridge, MA 02139Search for more papers by this author Arthur C. Upton MD, Arthur C. Upton MD Health Effects Institute—Asbestos Research, Cambridge, MASearch for more papers by this authorDr. Rashid A. Shaikh PhD, Corresponding Author Dr. Rashid A. Shaikh PhD Health Effects Institute—Asbestos Research, Cambridge, MAHealth Effects Institute-Asbestos Research, 141 Portland Street, Cambridge, MA 02139Search for more papers by this author First published: March 1995 https://doi.org/10.1002/ajim.4700270311AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Volume27, Issue3March 1995Pages 433-437 RelatedInformation

Comments on the Health Effects Institute-Asbestos Research (HEI-AR) report: "Asbestos in public and commercial buildings," with emphasis on risk assessment methods used.

A Health Effects Institute--Asbestos Research Report calculates the risk of exposure to environmental asbestos fibers (EAF) by downward extrapolation from the mortality of workers exposed for 20 years. This extrapolation is improper because 1) relative risks of asbestos exposure very likely are not linearly progressive; 2) the composition of EAF may not be equivalent to that in mining or fabricating; 3) the same environmental asbestos concentration probably represents different exposure doses for different populations; and 4) health effects of asbestos exposure on children, seniors, patients, the institutionalized, the handicapped, and the chronically ill may not be the same as those of healthy workers. Evidence of asbestos-related disease among family members of exposed workers demonstrates that the risk observed for EAF is substantially larger than that estimated from downward extrapolation and suggests a basis for an alternative approach to estimating asbestos-related health risks. Such epidemiologic procedures are well established and ought to form the basis for detecting the health effects of EAF. It is also unclear which industry supports HEI-AR.