Health impacts of coal: facts and fallacies.

Coal has contributed enormously to the advance of civilization by providing an abundant, inexpensive, and convenient source of energy. Concurrent with its contributions, coal has extracted a high cost in terms of environmental damage and human health impacts. Coal will remain a key component of the global energy mix for decades to come as well as a major source of global pollutants. Despite its high media profile, misconceptions about coal abound, especially with regard to its human health impacts. Coal also provides several excellent examples of how a geologic material and human health intersect in a variety of surprising ways. Unfortunately, the links between coal use and human health are distorted by a great deal of ignorance and misinformation. This paper discusses the facts and fallacies of the direct health impacts caused by coal (1, 2). There are a number of important health issues caused by coal that fall outside the scope of this review. The health impacts of particulates emitted from coal combustion have received substantial attention since the groundbreaking work of Wilson et al. (3), and through the recent discussions by Davis (4) and Freese (5). The indirect health impacts of coals through their contributions to global climate change, respirable particulates, acid rain, and acid mine drainage are also beyond the scope of this review. Greb et al. provide an excellent general overview of the environmental impacts of coal (6). The potential for health impacts caused by exposure to trace elements has received considerable attention for the past quarter of a century. The US Environmental Protection Agency conducted an extensive study of this issue and concluded (7) that, with the possible exception of mercury, there was no compelling evidence of health impacts caused by the emission of trace elements from coal-burning electric generating utilities. Nevertheless, documented examples do exist of health impacts caused by trace elements emitted by coal combustion. Bencko and Symon (8) described hearing problems in children living near a power plant burning high arsenic coal in the former Czechoslovakia. But, perhaps the most significant example of health impacts caused by trace element release from coal use occurs in Guizhou Province, southwest China, where millions of people suffer from dental and skeletal fluorosis and thousands suffer from arsenic poisoning due to mobilization of these elements by burning mineralized coals in unvented or poorly vented stoves (Figs. 1a and b).