Breathe Deep, Boys: Voices of the McIntyre Powder Project Miners.

Northern Ontario gold and uranium miners represent the largest cohort of industrial laborers who were historically exposed to daily nonconsensual industrial medical treatments involving the inhalation of finely ground aluminum dust known as McIntyre Powder. The daughter of one of those miners founded the McIntyre Powder Project in 2015 to document health issues in exposed miners, in an effort to determine whether her father's Parkinson's was related to aluminum inhalation. In response, 553 miners registered with the McIntyre Powder Project between 2015 and 2021 either directly or by their next-of-kin. This paper compiles their lived experiences of being subjected to McIntyre Powder, which contrasts starkly with the official narrative of the northern Ontario mining industry, which licensed its use globally. Additionally, this paper illuminates concerning industrial practices that emerged from the miners' disclosures, involving incentivized claims suppression, and raising serious questions about the effectiveness of medical screening and regulatory enforcement.

Sarcoidosis in Northern Ontario hard-rock miners: A case series.

Sarcoidosis is a rare multisystem granulomatous disease traditionally considered to be of unknown etiology. The notion that sarcoidosis has no known cause is called into question with the increasing number of case reports and epidemiologic studies showing associations between occupational exposures and disease published in the past 10-20 years. Occupational exposures for which associations are strongest and most consistent are silica and other inorganic dusts, World Trade Center (WTC) dust, and metals. Occupations identified as at-risk for sarcoidosis include construction workers; iron-foundry and diatomaceous earth workers; WTC emergency responders; and metal workers. We report here 12 cases of sarcoidosis in a cohort of hard-rock miners in Northern Ontario, Canada. To our knowledge sarcoidosis has not been reported previously in hard-rock miners. The cases are all male and Caucasian, with average age 74 years. At the time of diagnosis, two were never smokers; six, former smokers; and four, current smokers. Five have extrapulmonary sarcoidosis: two cardiac and three endocrine (hypercalciuria). Using occupational histories and air sampling data from the gold, uranium, and base-metal mines in which they worked, we examined exposure of each case to respirable crystalline silica (RCS). The annual mean RCS exposure for the 12 cases was 0.14 mg/m3 (range: 0.06-1.3 mg/m3 ); and the mean cumulative RCS exposure was 1.93 mg/m3  years (range: 0.64-4.03 mg/m3  years). We also considered their exposure to McIntyre Powder, an aluminum powder used for silicosis prophylaxis.

Trading One Risk for Another: Consequences of the Unauthenticated Treatment and Prevention of Silicosis in Ontario Miners in the McIntyre Powder Aluminum Inhalation Program.

From 1943 to 1979, miners and factory workers in more than two hundred work sites globally were subjected to mandatory medical treatments by their employers as an unproven, and ultimately ineffective, treatment to prevent the lung disease silicosis. The treatments involved inhaling finely ground aluminum dust known as McIntyre Powder, blown into miners' change rooms each shift using compressed air systems. Tens of thousands of industrial laborers were exposed to McIntyre Powder, yet their story is scarcely known, and the possible health impacts of their aluminum treatments were rarely studied. This paper integrates the history of the aluminum prophylaxis program and its control by the northern Ontario mining industry with the lived experience of one of the affected miners, whose daughter created a voluntary registry which documents health issues in exposed miners, and stimulated research that found a link to her father's Parkinson disease.