New research links cardiovascular disease to McIntyre Powder exposure

The medical records of Ontario miners exposed to McIntyre Powder over the years are giving up more information about the long term impact of aluminum dust on their health.

A new study published in the American Journal of Industrial Medicine finds a link between occupational exposure to McIntyre Powder and cardiovascular disease.

McIntyre Powder was a fine dust containing aluminum developed in Timmins that was dispersed in the air before each shift and miners told to breathe it in, as a method to coat their lungs and prevent silicosis.

It was licensed for use in mines around the world including in South America and western Australia and was used between the mid-1940s and 1979.

The study comes on the heels of research commissioned by the Workplace Safety and Insurance Board in 2020 that found a link between McIntyre Powder exposure and the development of neurological diseases, such as Parkinson's.

Andrew Zarnke is the executive director of Occupational Health Clinics for Ontario Workers in Sudbury, Ont.,and one of the authors of the most recent research.

He and other researchers delved into a database containing information on miners and their health records, eventually looking at more than 25,000 them.

There was no evidence that it was beneficial to miners' health and in 2022, then-labour minister Monte McNaughton apologized to miners and their families for the harm it had caused.

Zarnke says the new study finds a "robust" link between exposure to the fine particulate and heart disease, especially after many years of exposure.

"There was a strongest association at greater than 20 years of McIntyre exposure, which, for heart attacks or acute myocardial infarctions, there was about a 50 per cent increased rate in exposed mine workers," he said.

He added even after one to five years of exposure, they saw the incidence of heart attacks start to climb.

After 20 years of exposure, the incidence of congestive heart failure also rose to more than 60 per cent.

The study does not surprise Janice Martell, whose father was exposed to McIntyre Powder on the job and eventually died of Parkinson's.

She has led a campaign, called the McIntyre Powder Project, to register miners and their health information to educate people about the use of the aluminum dust and press for workers' compensation.

While the Workplace Safety and Insurance Board (WSIB) started accepting claims from McIntyre-exposed miners who developed neurological disorders in 2022, Martell thinks it should expand its criteria based on this new research.

"I think that WSIB should be compelled to look at this because those numbers show even greater risk than Parkinson's, which they had put as an occupational disease schedule three in the legislation," she said. "So I do think that they need to take a look at this."

Martell said she'll be encouraging miners she knows who developed heart disease and were exposed to McIntyre Powder to apply to the WSIB for compensation.

Workplace Safety and Insurance Board will review the research

Whether they'll be successful or not remains to be seen.

In a statement, WSIB spokesperson Christine Arnottsaid people are encouraged to make claims.

"The use of McIntyre Powder in the mining industry was a tragic mistake that has impacted too many lives," read the statement.

Arnott referred to the 2020 study the WSIB commissioned into the neurological impact of McIntyre Powder exposure and said that as more evidence develops, they always want to review it. She said their team, including their chief medical officer, will review the new study.

They'll base decisions on the best available scientific evidence as well as information about the person's illness, workplace exposures, and other relevant factors, she said.