In a recent report, the U.S. Environmental Protection Agency (EPA) has concluded that, with the possible exception of mercury, there is no compelling evidence that emissions from U.S. based coal-burning electric utility generators cause human health problems (EPA 1998). However, worldwide, the use of poor quality coal and/or the improper use of coal may cause or contribute to significant widespread human health problems. Health problems caused by impurities in coal, such as arsenic and fluorine, have been reported from the former Czechoslovakia (Bencko 1997) and from China. The World Bank (1992) estimates that between 400 and 700 million women and children are exposed to severe air pollution, generally from cooking fires. A substantial proportion of these people rely on coal for domestic cooking and heating and are thereby exposed to particulates, metal ions, gases (such as SOx), and organic compounds causing potentially serious respiratory problems and toxic reactions. Although addressing human health problems is the domain of biomedical and public health scientists, geoscientists have tools, skills, databases, and perspectives that may help the medical community address environmental health problems. Geoscientists are best equipped to characterize natural resources such as rocks, soils, and water. Various analytical tools used to characterize these natural materials have also been used effectively to characterize materials such as ambient dust and the products of coal combustion that cause or contribute to human health problems. In this chapter, we describe some of the geologic and geochemical tools being used to address arsenism and fluorosis caused by residential coal combustion in Guizhou Province, China. Wood had long been the primary energy source in southwest China, but by the early part of the twentieth century the forests were largely denuded and the residents were forced to use alternate sources of fuel. In southwest Guizhou Province, surface exposures of coal are plentiful and coal quickly became the primary fuel for domestic use. Unfortunately, some of these coals have undergone mineralization, causing their enrichment in potentially toxic trace elements such as arsenic, fluorine, mercury, antimony (Sb), and thallium (Tl). Burning the mineralized coals in unvented stoves volatilizes toxic elements and exposes the local population to these emissions.