Asbestos biologic/health effects

In Chapter 2 we introduce some basic concepts from mineralogy and materials sicence before describing several mineral and synthetic fibrous inorganic materials. In Chapter 3 we outline the physiology of the human lung, cellular biology and the diseases associated with asbestos exposure—the pertinent information for discussions of the health effects of asbestos and other inorganic fibers. 

Bogovski, P. J., C. Gilson, V. Timbrell, and J. C. Wagner, eds. (1973). Biological Effects of Asbestos. World Health Organization/International Agency for Research on Cancer, Lyon, France. Fhib. 8. 

The potential for unusual health effects of chemical mixtures due to the interaction of chemicals or their metabolites (e.g., metabolites of trichloroethylene and benzene) in or with the biosystem constitutes a real issue in the public health arena. However, toxicity testing to predict effects on humans has traditionally studied one chemical at a time for various reasons convenient to handle, physiochemical properties readily defined, dosage could easily be controlled, biologic fate could easily be measured, and relevant data were often available from human occupational exposures. Chemicals are known to cause disease for example, arsenic and skin cancer, asbestos and lung cancer, lead and decrements of IQ, and hepatitis B predisposes to aflatoxin-induced liver cancer but the link between the extent of human exposure to even well-defined chemical mixtures and disease formation remains relatively unexplored, but of paramount importance to public health. 

The purpose of this book is to introduce fibrous inorganic materials, their unique features, and their chemical and structural variety. This survey of fibrous materials, together with a summary of their health and biological effects, provides an opportunity to examine the current theories of disease induction and the hazards associated with exposure, not only to asbestos but to other inorganic fibers as well. 

Lee DH. 1974. Biological effects of ingested asbestos Report and commentary. Environ Health Perspect 9 113-122. 

The major sources of air pollutants found in buildings are described below. However, the mere presence of a potential contaminant source does not necessarily mean that exposure will ensue. This is because the extent of exposure, if any, often depends on the physical nature of a source or the manner in which it is used an example of this is asbestos, as will be discussed later. Furthermore, the health significance of exposure to indoor pollutants may not always be clear. While many of these toxicants may have adverse effects under exposure conditions found in occupational and other environments, often much less is known about biological responses with prolonged exposures at concentrations common in indoor environments. 

Soil plays an integral part in our lives and is inherently linked to public health. For example, many of the essential trace elements which we require in our diet to remain healthy are derived from soils and parent rock material, and low concentrations or the unavailability of these elements in soil can cause dietary deficiencies. Soils can also be contaminated with a range of potentially hazardous substances (both chemical and biological) which, if present at sufficiently elevated levels, can present a potential public health problem. For example, soils may contain elevated levels of heavy metals such as cadmium and lead which can have measurable and often severe effects on local populations. The soils of Cappadocia in central Turkey are naturally rich in fibrous asbestos-like minerals that are thought to be the cause of a rare cancer in local communities1 while exposure to the bacterium Clostridium tetani in soils can cause tetanus. Despite such examples, the effects of contaminated land have, until recently, been relatively ignored and, even today, our understanding of the mechanisms and level of risk associated with contaminated land is poor in relation to air and water. 

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