Physical and chemical characterisation of McIntyre Powder: An aluminium dust inhaled by miners to combat silicosis


McIntyre Powder (MP) is a finely ground aluminium powder that was used between 1943 and 1979 as a prophylaxis for silicosis. Silicosis is a chronic lung disease caused by the inhalation of crystalline silica dust and was prevalent in the Canadian mining industry during this time period. The McIntyre Research Foundation developed, patented, and produced the MP and distributed it to licensees in Canada, the United States, Mexico, Chile, Belgian Congo, and Western Australia. In the province of Ontario, Canada it is estimated that at least 27,500 miners between 1943 and 1979 were exposed to MP. The present study was undertaken to examine the chemical and physical characteristics of two variations of MP (light grey and black). Chemical analyses (using X-ray Fluorescence and Inductively Coupled Plasma approaches) indicate that the black MP contains significantly higher concentrations of aluminium and metal impurities than the light grey MP (p?

Authors: Zarnke A, Rasmussen PE, David MO, Eidi H, Kennedy K, Hedges K, Irick T, Thome C, Pirkkanen J, Boreham D.
; Full Source: Journal of Occupational & Environmental Hygiene. 2019 Sep 18:1-12. doi: 10.1080/15459624.2019.1657581. [Epub ahead of print]