Manganese mining in Corral Quemado: extractivism Processes that resulted in manganese madness among miners (Coquimbo region, Chile, 1941–1969)

This study reviews the working conditions of the miners of Corral Quemado, near Andacollo in the Coquimbo region of northern Chile, during the extraction and processing of manganese between 1941 and 1969. The extractivism’s extraction techniques, mineral processing methods, and mining policies are presented and discussed. The poor working conditions in the mines led to significant manganese overexposure, resulting in a condition known as ‘manganese madness’ in the miners. Prolonged exposure to manganese causes several health complications that affect the central nervous system, resulting in psychomotor problems, body stiffness, involuntary movements, and facial spasms, in addition to psychological issues (compulsive behavior, emotional lability, and hallucinations, among others). Given that the negative effects of manganese poisoning, which were first reported in Europe in 1837, were already well known, the historiography and health condition of the Andacollo miners require attention. The Andacollo miners’ precarious working conditions and the manganese toxicity created lasting mining and economic issues, and left a permanent imprint on the miners’ bodies. At the time, miners’ dramatic working conditions and disabling injuries prompted a series of parliamentary petitions aimed at improving their working conditions.