Canadian Occupational Safety

20 Canadian Occupational Safety | www.cos-mag.com R ay Mills worked at four of the five Rio Alco mines in Elliot Lake, Ont. for 29 years. At the start of his shift, he was required to walk through a room where black aluminum dust was sprayed through compressed air. "Everybody had to walk through it," says Mills, who is 77 years old and lives in London, Ont. "If you hap- pened to be there when they turned the air on, it was a big black cloud of it… The canister was about the size of a soup can. He might put two cans out before each shift." The dust was McIntyre Powder and it was used as a method to prevent miners from developing silicosis at many mines in northern Ontario between 1943 and 1979. The prov- ince's records reveal 27,500 miners were exposed to aluminum dust. The dust was also used in mines in Quebec, British Columbia, Manitoba, Saskatchewan and the Northwest Ter- ritories as well as the United States and around the world. Additionally, some workers who were exposed to silica dust in pot- tery manufacturing, foundries, silica brick manufacturing and refractories were also subject to the McIntyre Powder treatment. Developed by t he Mc Int y re Research Foundation — which was made up of executives from McIntyre Porcupine Mines in Schumacher, Ont. — the belief was that coating the miners' lungs with aluminum dust would protect them from con- tracting silicosis. Mills says the method wasn't ques- tioned at the time among the miners. "It was there. You never talked about it. You just carried on," he says. In 2015, Mills was diagnosed with Parkinson's disease — and now he has some questions. He says McIntyre Powder is "very high on the suspect list" in terms of what led to his diagnosis. The practice of inhaling McIntyre Powder has garnered much media, industry and political attention in recent years, as exposed miners have developed health conditions in stag- gering numbers. Out of 452 miners (both living and dead) on the McIntyre Powder Project list, two-thirds have respira- tory disorders and one-third have neurological disorders. The most common neurological disease is Par- kinson's with 43 miners out of 452 being diagnosed with the condition. Alzheimer's is also common, with 27 miners being diagnosed, followed by dementia in 16 miners. There are 97 cancer diagnoses on the list, 47 of which are for lung cancer. There are also some relatively obscure conditions such as Lewy body dementia, progressive supranuclear palsy and amyotrophic lateral sclero- sis (ALS), also known as Lou Gehrig's disease. According to ALS Canada, the lifetime risk of developing ALS is 1 in 1,000 — but there are 14 known cases of ALS among the miners. Many miners have multiple health issues and others have symptoms of a disorder but do not have a diag- nosis yet. The McIntyre Powder Project is a voluntary registry to document health issues (particularly neurological) in miners and other workers who were exposed to McIntyre Powder aluminum dust in their workplaces. The project was started by Janice Martell whose father, Jim Hobbs, worked in nickel and uranium mines in Ontario and breathed in McIntyre Powder everyday. In 2014, Martell began investigating the practice after she suspected a pos- sible connection between the powder and her father's Parkinson's disease diagnosis. Hobbs succumbed to the disease and passed away last May. BACKGROUND Beginning in 1932, researchers from McIntyre Porcupine Mines tested McIntyre Powder with 50 guinea pigs and 13 rabbits. These studies showed that while silicosis was produced in five months in the control animals that inhaled silica dust, the addition of aluminum powder to the silica dust completely prevented the occurrence of silicosis, even after exposure for up to 22 months. In 1941, the McIntyre Porcupine Mines began testing aluminum dust inhalation as a treatment for miners who had silicosis. The camp had 350 miners with silicosis, but after review- ing X-rays and eliminating those who were "foreigners" or "of the non-coop- erative type" just 20 were selected to receive treatment, according to an archival document from the powder's co-creator, W.D. Robson. The treatment consisted of a five- minute inhalation of aluminum powder daily, with sessions increasing by five minutes every few days until one month had passed. After one month, the patient began receiving 30-minute inhalation sessions daily. The treatments continued for six days per week until 200 treatments had been administered. The first 10 miners that were treated had shown "remarkable results," Robson said. However, two cases did not respond to the treatment. In both cases, when the disease was examined by X-ray, it presented as clear-cut nod- ulation. Those that responded well to the treatment had a snowflake appear- ance when examined by X-ray. In a meeting between Robson and American doctors who were visiting the silicosis clinic, it was concluded that X-ray films of each individual case should be carefully studied to determine if they would respond well to the aluminum therapy or not. They agreed the clinic should continue with rigid selection of cases for treatment because "if one went bad, whether it was due to aluminum treatment or not, the method would be discredited." Ultimately, the men said it was only a matter of time before "the treatment of silicotics by the inhala- tion of aluminum powder would be accepted without question." In the end, 100 miners were treated as part of this initial research. But there are a slew of issues with this research, namely the fact that a control group was never used nor was the random selection process — the researchers picked and chose the men they wanted to participate in the treatment. During that meeting in 1941, Anthony Lanza from the Metropolitan Life insurance company in the United States pointed out that the industry would make its greatest savings in compensation from the prophylac- tic (prevention) end than from the treatment of already established and compensated cases, and the industry should be granted the right to use pre- ventative measures as soon as possible. It's important to note, however, there had never been any scientific evidence of McIntyre Powder's pre- ventative effects against silicosis. Most Miners forced to inhale aluminum dust decades ago are developing neurological diseases in staggering numbers By Amanda Silliker

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