Marion G. Williams

Tissue burden of asbestos in nonoccupationally exposed individuals from east Texas

BACKGROUND The potential for asbestos exposure among members of the general population is appreciable, considering its widespread use in many products. This study examined tissue burden of asbestos in such a population. METHODS A group of 33 individuals who had no work history of occupational exposure to asbestos were included in the study. Tissue sections from areas adjacent to those sites sampled for digestion were found to be without ferruginous bodies (FB) or histopathology consistent with asbestos-induced changes. All individuals had 20 or less FBs per gram of digested wet lung, a number considered to reflect general population levels. Tissue analysis of uncoated fiber burden was carried out by analytical electron microscopy. There was a trend of a higher likelihood of FB and asbestos fiber content correlated with age. RESULTS The data are not consistent with the findings that chrysotile is readily found in lung tissue from the general population, in that none was found in 19 of the cases. It was almost as likely that one would find anthophyllite (12 of 33 cases) in this study. The commercial amphiboles (amosite and crocidolite) were occasionally found in the tissue from the general population and, when observed, were few in numbers. Twenty-six of the patients had no FBs and ten had no uncoated asbestos fibers within the limits of detectability in this study. CONCLUSIONS The total tissue burden of asbestos in this study is much less than earlier reported observations from other general populations.

Faith-based intervention in depression, anxiety, and other mental disturbances.

Objective: To determine if the effects of using the Steps to Freedom would be beneficial for a group of individuals who attended a Christian Conference. Methods: A user-friendly 12-item questionnaire was used to monitor the outcomes of Steps to Freedom addressing six symptom/behavioral problems and six function areas. In addition, the Symptom Checklist-90 R (SCL-90-R) questionnaire was employed to document the validity of the shorter questionnaire. The questionnaires were completed before and after the administration of the Steps to Freedom. The Wilcoxon matched pairs test was used to measure the significance of the findings for the 12-item questionnaire. Results: Thirty-three clients who went through the Steps to Freedom showed statistically significant improvement (P ≤ 0.005) at 3 to 4 months in all symptom/behavior categories (items 1–6). All function areas (items 7–12) also demonstrated statistically significant improvement (P ≤ 0.05). A comparison group who did not attend the conference or receive counseling showed no significant changes during the same period. Conclusions: These significant preliminary findings need to be confirmed by additional studies. Steps to Freedom model prayers, used by individual patients personally and/or with a counselor, could expand the care and hopefully lower the cost of mental illness.

Early response of free airway cells to "amosite": a correlated study using electron microscopy and energy dispersive X-ray analysis.

The acute response of free airway cells following an intratracheal injection of “amosite” was studied by light microscopy, electron microscopy and energy dispersive analysis. It was determined that the use of fixative as a lavage fluid provided a superior level of morphological information. The free cell population consisted of macrophages, neutrophils, eosinophils, lymphocytes and monocytes. The early phagocytic response (2 or 4 hours post injection) largely involved the neutrophil population with a minimal uptake of fibers by macrophages. There was an increased population of lymphocytes in the free cell preparation after the first week.The intramacrophagic response to particle ingestion consisted of two types of intracellular packaging, representing different stages of the same process. While some fibers were simply membrane-bound, large numbers of fibers were within siderosomes. These iron-rich organelles were also shown to be present within macrophages obtained from untreated controls.Both inorganic contaminants and organic asbestiform-like entities were observed within macrophages. The latter were found to be normal constituents of macrophages in the control samples. These observations emphasize the importance of supplementing identification of intracellular fibers by analytical methods.

Asbestosis and small cell lung cancer in a clutch refabricator.

OBJECTIVES: To present a case of asbestosis and small cell lung cancer caused by asbestos in a clutch refabricator. METHODS: Exposed surfaces of used clutches similar to those refabricated in the workers workplace were rinsed, and the filtrate analysed by analytical transmission electron microscopy. Tissue samples were also analysed by this technique. RESULTS: Numerous chrysotile fibres of respirable dimensions and sufficient length to form ferruginous bodies (FBs) were detected from rinsed filtrates of the clutch. Bronchoalveolar lavage fluid contained many FBs, characteristic of asbestos bodies. Necropsy lung tissue showed grade 4 asbestosis and a small cell carcinoma in the right pulmonary hilum. Tissue analysis by light and analytical electron microscopy showed tissue burdens of coated and uncoated asbestos fibres greatly exceeding reported environmental concentrations (3810 FBs/g dry weight and 2,080,000 structures > or = 0.5 micron/g dry weight respectively). 72% Of the cores were identified as chrysotile. CONCLUSIONS: Clutch refabrication may lead to exposure to asbestos of sufficient magnitude to cause asbestosis and lung cancer.

Asbestos burden in two cases of mesothelioma where the work history included manufacturing of cigarette filters.

Asbestos has been used in many applications, but possibly one of the more unique was in the manufacturing of filters for cigarettes. The type of asbestos used in this application was crocidolite. Data from several resources indicate that crocidolite was one of the least utilized types of commercial asbestos in the United States. The present study provides quantitative tissue burden analysis data for two mesothelioma cases where the work histories included manufacturing of cigarette filters that contained crocidolite. The data include the number of asbestos bodies and uncoated fibers per gram of tissue, as well as the dimensions of these structures. The conclusion of the findings indicates that the individuals had an appreciable homogeneous exposure to crocidolite asbestos.

An assessment of asbestos body formation in extrapulmonary sites: liver and spleen:

Study Objectives: Asbestos bodies (ABs) form as asbestos fibers become coated by a cellular iron- and protein-rich matrix. ABs have been reported in lymph nodes and a few extrapulmonary sites, but no data exist as to their formation outside of the lung. It is not clear whether the AB found in these extrapulmonary areas have been transported as mature structures from the lung or formed at the extrapulmonary site. This study was designed to determine if ABs are produced in extrapulmonary sites. The guinea pig efficiently forms ferruginous bodies in the lung and so it was chosen as a model to test the coating efficiency of amosite asbestos fibers in lung, liver and spleen. Design: Sized amosite asbestos (5 mg) was administered either endotracheally into lung (n=2) or directly into liver (n=4) and spleen (n=4) of healthy 10-week-old male guinea pigs. The lung, liver and splenic tissues were removed at 40 and 180 days post inoculation and were examined histologically for the presence of AB via light microscopy. Uncoated fibers isolated from the tissues were characterized by electron microscopy. The coating efficiency was calculated as a ratio of uncoated/coated fibers per organ. Results: The coating efficiency ratios of fibers that were collected at 40 days post-injection from the individual sites were: lung—350:1, liver—4200:1, and spleen—220,000:1. At 6 months post-injection the ratios for the individual sites consisted of: lung—176:1, liver—11,000:1, and spleen—1000:1. Conclusion: This study indicates that AB can be formed in extrapulmonary sites and that the coating efficiency in the lung is much greater than that within the liver or spleen.

Non-Asbestos Fibre Burden in Individuals Exposed to Asbestos

The characteristics of asbestos, which cause it to be classified as a carcinogen, have been the subject of numerous investigations. While various mechanisms might contribute to its overall cancer producing potential, the physical characteristics of asbestos are widely recognized as major factors. The relationship of fibrous form to tumour production is often referred to as conforming to the “Stanton Hypothesis.” The model used by Stanton incorporated non-asbestos fibres which were of a similar dimensions to asbestos fibers. Appreciable attention has been given to assessing lung tissue asbestos burdens in a number of cohorts; however, limited information exists on the amount of “non-asbestos” fibres in the lung. Since the “Stanton Hypothesis” includes fibres of a given dimension and not mineral type, it is important to gain more information on the presence and characteristics of non-asbestos fibres and their possible contribution to the development of disease.

An ultrastructural study of acute and long-term lung response to commercial diatomaceous earth

The acute pulmonary effects of intratracheally instilled particles of calcined diatomaceous earth were found to include a pronounced neutrophil invasion of the bronchioles by 4 h after exposure which remained well developed through 1 day post-exposure. The number of macrophages and neutrophils in the alveoli continued to increase through 1 day post-exposure and remained above control values through 7 days post-exposure. The number of macrophages, many of which contained diatomaceous earth, remained elevated for the duration of the experiment. Most phagocytosis of the particles was carried out by macrophages, with minor participation by neutrophils. Many of the reactive macrophages in the groups with post-exposure periods longer than 2 h showed various types of pathological alterations. A few particles were found in type I epithelial cells. Oedematous changes were observed in some type I epithelial cells and proliferation of type II epithelial cells was evident in some alveoli, particularly those near the respiratory bronchioles. Mild diffuse fibrosis was first observed at 6 months and was still present at 15 months but remained confined to the areas containing the diatomaceous earth.

An ultrastructural study of the blood/air barrier in the guinea-pig

Horseradish peroxidase (HRP) was intravenously injected into guinea-pigs to ultrastructurally examine the permeability of the blood/air barrier. Adults were given 300 mg/kg of the tracer in a small volume of saline, anesthetized and sacrificed at intervals by either intratracheal filling or right ventricular perfusion with 3% glutaraldehyde. The reaction product had passed through endothelial clefts and accumulated in the interstitium as early as 1.5 min after injection. This same degree of penetration occurred with either fixation method used. Tight junctions between pneumocytes prevented passage of the reaction product into alveoli. Pinocytotic vesicles were numerous in both endothelial and epithelial cells, but did not significantly contribute to tracer transport. Ten minutes post-injection was selected as optimal for this model since the highest concentration of tracer was found in the tissues at this time.