McIntyre Powder study supports need for future research: Nanoparticles found in aluminum dust administered to miners.

• Author: Kelly, Lindsay

Researchers are hopeful that newly discovered details about the composition of McIntyre Powder will prompt a look into the biological impact of the aluminum dust on former miners who inhaled it.

The findings are included in a new report led by researcher Andrew Zarnke, a PhD candidate at Laurentian University in Sudbury, entitled "Physical and chemical characterization of McIntyre Powder: An aluminum dust inhaled by miners to combat silicosis."

The report was published in mid-September in the Journal of Occupational Environmental Hygiene and is now available online as a free download.

It was already widely known that McIntyre Powder was largely comprised of ground-up aluminum. But learning the size of the particles in it, along with its chemical makeup, helps form a baseline for future biological experiments that may explain how the powder impacted miners' long-term health, Zarnke said.

"If we see a response (in the body), we need to understand what about the powder might be causing the response," he said during a Sept. 23 presentation of his findings in Elliot Lake.

"So it was essential to understand what was in McIntyre Powder and as much detail about it as possible."

Zarnke spoke alongside Janice Martell, an advocate for miners who were impacted by McIntyre Powder, and Dr. Christine Oliver, a physician and consultant lending her expertise in lung function. All three are doing work for the Occupational Health Clinics for Ontario Workers (OHCOW) in building a database of former miners, their work histories and their health records.

Created by mining executives as a way to prevent silicosis in underground miners who were developing the lung disease after inhaling silica dust, McIntyre Powder was blown into the mine dry before a shift, and workers were only released after they had inhaled the dust for about 10 minutes.

It was later revealed that the powder had no benefit to miners' health, yet the practice persisted for nearly 40 years, impacting 27,500 miners in Ontario gone.

Today, many of those miners are living with a range of illnesses --cardiovascular, respiratory, and neurodegenerative, along with a range of cancers--that they believe McIntyre Powder could have caused.

Zarnke's research builds on a 1940s analysis conducted by the McIntyre Research Foundation, the organization comprised of mining executives that was responsible for developing McIntyre Powder.

That initial research found that about 24 per cent of the particles measured...