Annual Report 2022-2023


Occupational Illness

OHCOW’s clinical work, large cluster investigations, and vulnerable worker lens, provide a unique perspective on a full circle occupational illness/disease prevention approach (primary, secondary and tertiary) and continue to provide leadership to Ontario’s Occupational Illness Prevention System Focus. 

Though the global pandemic has created continuing demands for the latest science and prevention tools in response to COVID-19, it has also fostered an unprecedented public awareness of Occupational Illness/Disease and the Hierarchy of Controls. This awareness can and must be leveraged to the longer latency priorities of the Occupational Illness Prevention Plan. 

Occ|tober 2022: Worker-Focused Science & Prevention Webinars

occtober webinarPreventing Occupational Illness/Disease is an Area of Focus in Ontario’s Prevention Works 5-year strategic plan. OHCOW leads the Occupational Illness Steering Committee (formerly the Occupational Disease Action Plan (ODAP)) aligning the efforts of the Occupational Health and Safety System and partners to reduce the incidence and burden of occupational illness/disease whether chronic/long latency or more acute/infectious.

The 2022 Occ/tober session Kickoff event was online October 27, and featured Chief Prevention Officer Dr. Joel Moody. He spoke about the Collective Impact of the Occupational Health & Safety System Partners efforts through the Occupational Illness Prevention Steering Committee (OISC) (formerly the Occupational Disease Action Plan -ODAP).  This includes bringing the Silica Control Tool to Ontario, the Occupational Disease Review, and the upcoming Healthy Worker in Healthy Education & Enforcement Initiatives.

As the sessions continued into November, topics included the Diesel Exhaust Exposure tool, and addressed other occupational exposures. Speakers include: MLITSD Program Leads (Industrial, Mining, Healthcare, Radiation) Cristina St. Pierre, Provincial Hygienist, William Roy, Director, Strategy and Integration, MLITSD, Kimberly O’Connell, Executive Director, OHCOW (Co-Chairs OISC).

October 27, 2022: Worker-Focused Science & Prevention Webinars Kickoff Event

November 3, 2022: Diesel Exhaust Exposure – Influencing Change

November 10, 2022: Occupational Exposures and Community Responses

November 17, 2022: Worker Informed Science: Learning and Collaborating

November 24, 2022: Making It All Easier: Knowledge Mobilization & Tools Webinar

Rubber Worker Project

The Rubber Worker Project is one of OHCOW’s most long-standing projects. Research has shown that there are links between certain rubber industry exposures and health impacts experienced by workers, including cancer outcomes. In this project, we aim to review and conduct research on potential connections between rubber work and health as well as share our learnings with rubber workers and their families to help: (1) prevent or reduce harmful exposures at work, (2) synthesize medical and hygiene evidence for worker’s compensation claims, and (3) identify areas for further research.

What did we accomplish this year?

We are organizing our rubber worker client database to prepare for further case support.

  • We have created an improved database to organize our patient medical and exposure data.
  • This database will help us to better support workers and their families with exposure prevention and worker’s compensation matters.
  • This database will also allow us to investigate emerging links between certain workplace exposures and health outcomes.

We are reviewing groups of cases organized by common diagnoses and exposures to identify known and emerging patterns.

  • This year, we have focused on reviewing groups of bladder cancer, lung cancer, and salivary gland cases to learn more about any potentially-linked exposures.
  • We will continue to review other outcomes of concerns raised by rubber workers and their families.

We are preparing a salivary gland cancer case series publication.

  • In the scientific literature, there is early evidence that employment in the rubber industry may be associated with development of salivary gland cancer.
  • Salivary gland cancer is a rare cancer of the salivary glands, which are the glands that produce saliva in your mouth.
  • We are working with rubber workers who have been diagnosed with salivary gland cancer to better understand the exposures they may have experienced.
  • We aim to publish this work in a scientific journal article in 2023.

We hosted a focus group with rubber worker retirees (SOAR) to learn more about exposures.

  • We met with a small group of rubber retirees to interview them about exposures they may have experienced in the plants in which they worked.
  • This will help us to build additional evidence of potential connections between the illnesses they are experiencing and exposures they may have experienced.

We have been engaged in archival research, finding historic photos and maps of rubber industry plants to learn more about the processes used in the past. These photographs will be shared on our website (if possible),  as we use them to inform our research on plant processes and exposures.

What’s coming next?

  • Expanding worker outreach in 2023-2024, including to active rubber workers
  • Hosting a public information session to share our findings to date.
  • Continuing to support workers with exposure prevention and workers’ compensation matters.

We want to hear from you!

  • Have you and/or your family members worked in the rubber industry?
  • Do you have concerns about the impact of your work on your health?

See the OHCOW Rubber Worker Project page, and contact us anytime for a medical or exposure prevention consultation at

McIntyre Powder Project

This was an exciting year for the McIntyre Powder Project, in which years of dedicated work saw the result of an established fund to compensate workers who became afflicted with Parkinson’s Disease due to their exposure to McIntyre Powder when working in Ontario mines.  OHCOW researchers share in this success. Below are summaries of 2022/23 milestones and accomplishments for this important project. For more information, Go to the OHCOW McIntyre Project page for more information.

OHCOW Researchers Make Valuable Contributions to Study of Occupational Illness Caused by McIntyre Powder

McIntyre Powder (MP) was administered to miners for decades in Ontario mines in the belief that it prevented silicosis. OHCOW researchers have helped determine the harmful and life-long damage to miners’ health caused by preventable exposure to the substance.

The latest paper, “McIntyre Powder and its potential contributions to cardiovascular disease risk: A literature review through the McIntyre Powder historical lens,” appears in the American Journal of Industrial Medicine. Published in June of 2022, the study was published by Andrew M. Zarnke, BSc., an Occupational Hygienist at OHCOW, Sudbury; and Christine Oliver, MD, a medical consultant to OHCOW and an Adjunct Professor at the University of Toronto in the Division of Occupational and Environmental Health.

In this research Zarnke and Oliver continue their study of the period from 1943 to 1979, when mine workers in Ontario (as well as other locations throughout Canada and worldwide) were exposed to the powder in their workplace, often in high concentrations. The degree of fineness of the powder, along with its high concentration when used in the mines, resulted in a respirable dust that increased the lung dust burden of workers, causing lung disease over time. For ten minutes before every work shift, the powder was administered to miners.

Previous research by the team showed that the high airborne concentration that miners were exposed to caused lung damage, in combination with the respirable dust they breathed as they worked in the mines. Their recent study shows that, combined with the air pollution particulates already present in the environment, miners were also put at increased risk of cardiovascular disease (CVD).

Oliver and Zarnke have been studying occupational illness in miners for years. They previously wrote and co-wrote papers on sarcoidosis, an inflammatory lung disease. These papers are “Sarcoidosis: An Occupational Disease?”, published in 2021, and “Sarcoidosis in Northern Ontario hard-rock miners: A case series” published in the American Journal of Industrial Medicine in February 2022.

The research helped make the case for a strong causal association between occupational  exposure to MP and lung disease, damage to the immune system, and gene-exposure interactions.

OHCOW research has significantly contributed to the medical literature that has forced insurance granting organizations, such as the WSIB in Ontario, to reconsider their previous denials of compensation for miners exposed to MP. Its impact has been felt as well in other regions where the substance was used. The research is not over, as more connections are being found between exposure to MP and neurological damage in miners.

Miners Harmed by McIntyre Powder get Official Apology

Labour Minister Monte McNaughton On November 30, 2022.

Former mine workers who were made ill from their exposure to McIntyre Powder have received an apology from Ontario Labour Minister Monte McNaughton. Thanks in large part to the spearheading of the McIntyre Powder Project by activist Janice Martell and her partnerships with OHCOW and others, the substance has been identified as having caused respiratory illness, lung disease and neurological conditions in workers. Martell was interviewed on CBC about the campaign and what the long-awaited apology means to her and injured miners.

From 1943 to 1979, miners in northern Ontario were forced to breathe in the black ground aluminum dust before they started their shifts.

McIntyre Powder is essentially ground aluminum dust, and it was administered to miners for over thirty years until 1979. The miners were told they had to take it or be fired. It was supposed to prevent lung disease, but in some cases actually ended up causing it, as well as other illnesses and irreversible neurological damage.

The Workplace Safety and Insurance Board of Ontario (WSIB) has recognized that miners forced to inhale McIntyre Powder were at a higher risk of developing Parkinson’s disease. Early in 2022, the province made the changes to allow families and miners who developed Parkinson’s tied to McIntyre Powder inhalation to file claims and be compensated for occupational disease.

Millions in Unclaimed Compensation Available for McIntyre Powder Miners

This article by Dave Wilken was originally published in Northern Ontario Business, April 6, 2023.

Despite recent policy changes by Ontario’s Workplace Safety & Insurance Board (WSIB) that make it much easier for workers exposed to McIntyre Powder aluminum dust at gold and uranium mines between 1943-1979 to claim compensation for Parkinson’s disease, only a fraction of those eligible have been compensated. The issue has now shifted from bad, outdated policy and resulting legal hassles to getting the word out about a streamlined compensation process open to McIntyre Powder-exposed Parkinson’s sufferers and their families.

Compensation can include awards for lost wages, pain and suffering, reimbursement of non-OHIP-covered medical expenses, including long-term care or assistance with daily living activities while staying at home (including from family members), a stipend to cover other expenses such as yard work and household repairs and, where the condition is fatal, funeral expenses and death benefits. These benefits are available with full retroactivity, but without an application, the money stays in the WSIB’s multi-billion-dollar investment fund and never makes it to those who have suffered the human costs of this terrible disease. The employer-funded WSIB also keeps the money that would be refunded to OHIP for costs that it did cover for these work-related conditions.

Read the entire article here.


Ventra Plastics Plant

In 1981, a German firm manufacturing plastic automobile parts moved to Kitchener, Ontario in a 22,000 square-foot facility.  By 1986, parts were manufactured at this plant using an innovative process called “reaction injection molding.” With production expanding, the company set up a second facility in Peterborough, which was expanded in the late 1990s to accommodate its larger thermoplastic injection molding machines and production operations. Over the next decade (1986 to 1996), the Ventra Plastics workforce grew from 75 to 575 women and men, with production increasing from one product to 30 different products.

Over the years, Pebra/Ventra Plastics workers began to raise concerns about various health conditions, including but not limited to: (1) various cancers (e.g. lung, salivary gland, breast, etc.), (2) Chronic Toxic Encephalopathy, (3) reproductive issues, (4) cardiovascular disease, (5) among other health issues. In response, OHCOW initiated an investigation in partnership with plant workers and Unifor Local 1987. OHCOW continues to review and conduct research on potential connections between plastics production and health, as well as share our learnings with Pebra/Ventra workers and their families to help: (1) prevent or reduce harmful exposures at work, (2) synthesize medical and hygiene evidence for worker’s compensation claims, and (3) identify areas for further research.

What did we accomplish this year?

We are building our team to expand worker outreach and case support.​

  • We hired new staff this year to support the Ventra/Pebra project.
  • We mailed project update letters to workers and their families.​
  • Our team hosted two public (virtual) information sessions in February 2023.
  • We have been supporting workers and their families to navigate the WSIB claims process, including conducting health and work history interviews.

We are preparing a salivary gland cancer case series publication.​

  • In the scientific literature, there is early evidence that employment in the plastics production industry may be associated with development of salivary gland cancer.
  • Salivary gland cancer is a rare cancer of the salivary glands, which are the glands that produce saliva in your mouth.
  • We are working with plastics workers who have been diagnosed with salivary gland cancer to better understand the exposures they may have experienced.
  • We aim to publish this work in a scientific journal article in 2023.

We are completing an investigation of asbestos exposure at Pebra/Ventra.

  • Our team of hygienists have reviewed potential sources of asbestos exposure at the Ventra/Pebra plant.
  • We are currently working to prepare materials for workers and their families to summarize our findings.

We are reviewing worker cases of illness by common diagnosis (e.g. reproductive issue cases) to learn more about potentially-related exposures at the Pebra/Ventra plant.

  • We have onboarded a new doctor to support our case reviews.
  • We have created a new worker questionnaire focused on reproductive health issues.

What’s coming next?

  • We hope to expand worker outreach in 2023-2024, including to active Ventra/Pebra workers.
  • We hope to host a public information session to share our findings to date.
  • We will continue to support workers with exposure prevention and workers compensation

We want to hear from you!

  • Have you and/or your family members worked in the plastics production industry?
  • Do you have concerns about the impact of your work on your health?
  • Contact OHCOW anytime for a medical or exposure prevention consultation at

General Electric Plant

General Electric Production Facility in Peterborough

OHCOW has been actively engaged with the Peterborough community since 2004, with a particular focus on workers at General Electric and Pebra/Ventra Plastics and their families. Throughout 2021-2022, Out of the 825 General Electric Peterborough workers that have registered with OHCOW, 253 workers with respiratory conditions were identified and their claims were reviewed in detail to assist in obtaining further supporting documentation for these workers.

Through these outreach efforts new General Electric workers have come forward and registered with OHCOW and new worker’s compensation claims have been established with the WSIB. In response to a recent systematic literature review carried out at the University of British Columbia, commissioned by the WSIB, that investigated the relationship between gastrointestinal (GI) cancers and asbestos exposure an additional 10 workers with esophageal cancers have been included in the active follow-up and outreach to GE workers. The 253 workers with respiratory conditions, as well as the 10 workers with esophageal cancer, were also screened for eligibility for the Low Dose CT Scan lung cancer screening program through Cancer Care Ontario.


Dryden Weyerhaeuser Recovery Boiler

OHCOW continues to investigate the Dryden Weyerhaeuser Paper Mill Recovery Boiler #4 project which resulted in the exposure of hundreds of building trades workers to a recurring plume of toxic emissions. At the request of some of the unions involved, OHCOW conducted intake clinics in Dryden and Thunder Bay in November 2004, resulting in the registration of nearly 400 patient files and the filing of 160 health professional reports to WSIB, primarily regarding reported neurological effects. This was followed by the completion of a general report on the nature of the exposures and in-depth assessments of some of the most affected workers.

Currently, we have a total of 462 workers that have registered with OHCOW since the beginning of this project. 158 of these workers are currently active following our initial follow-up attempt during 2022. During 2022 the priority has been to help Dryden project workers with acquiring WSIB claim files, initiating new WSIB claim files focusing on cases of respiratory disease, cancers, and neurological disease. The local media has also taken an interest in this project and has assisted the Thunder Bay and District Injured Worker’s Group in raising awareness.

Occ-Covid Webinar Series

Science, Solutions and Success Stories

This year’s Occ-Covid series featured the usual high calibre expert speakers and discussion. Popular speaker Joey Fox, professional engineer and HVAC specialist, shared his knowledge in two sessions, Clean Air REALLY Matters and Let’s hear from the Engineers & stop the spread! Professionals Marianne Levitsky and Stéphane Bilodeau joined him. Roy T. McKay, Ph.D., Occupational Pulmonary Services,  was featured in the next session Why Respirators, Seal and Fit, Really Matter.

The Spring session featured world-leading Australian biosecurity expert Raina MacIntyre speaking about her new book on the topic. Investigation in outbreaks, maximizing good air quality and analyzing statistics were topics of subsequent webinars in the series.

OCC-COVID Webinars 2022/23


April 5, 2022: Frontline Mental Health, Stressors and Strategies for Workplaces

April 5, 2022: COVID-19 and Societal Inequities: A Look at the Impact on the Mental Health of Health workers

April 5, 2022: What the Evidence Suggests is Occuring for the Impact of COVID on Mental Health

April 22, 2022: Healthcare Implications Now and in the Future

April 22, 2022: Trust and the Noise of Misinformation

April 22, 2022: COVID-19: A Lesson on Environmental Justice

June 3, 2022: Protecting Teachers and Students – Optimizing Ventilation in Older Schools

June 3, 2022: Clean the Air and Commit to C.A.R.E.

June 3, 2022: Risk Assessment Toolbox


September 16, 2022: Clean Air REALLY Matters

October 7, 2022: Preventing Viral Transmission in the Workplace

October 14, 2022: Why Respirators, Seal and Fit, Really Matter

December 9, 2022: Let’s hear from the Engineers & stop the spread!

December 16, 2022: Critical Concepts in Ventilation & Viral Evolution

January 27, 2023:  Dark Winter – Past Lessons to Inform Future Health

February 10, 2023:  A 3 year check-up — Not “just the cold or flu”


The COVID & Infectious Diseases Reference Team (CIRT)


OHCOW had been monitoring COVID-19 as an infectious disease before it even had a name prior to the declaration of a pandemic. Initially known as the “novel coronavirus,” OHCOW adopted the precautionary principle, and recognized the need to develop an internal committee to monitor the rapidly evolving understanding of COVID-19 in order to recommend best practices for occupational health & safety. As the COVID-19 Response Team, it evolved to ensure that the leading evidence and best practices were shared with the workers of Ontario.

What has OHCOW done about it?

As COVID-19 has changed and advanced, research and knowledge around transmission and prevention has increased. In September 2022, the team published “Returning to the Office: COVID-19 Communicable Disease Prevention Plan.” This robust document included detail to keep our employees, contractors, clients, and their families as safe as possible. All layers of the hierarchy of controls for prevention were reviewed and as many layers as possible were implemented.

In an effort to educate as many people as possible, the team also organized information sessions called “Occ-COVID,” on a variety of topics related to COVID-19. Occ-COVID sessions have been hosted by OHCOW since 2020, inviting scientists, epidemiologists, physicians, nurses, and engineers to speak to the public about the latest research. Topics have included aerosol transmission, cleaning the air, computational fluid dynamics, engineering controls, investigating outbreaks, respiratory protection, wastewater monitoring, among many, many other sessions.

As COVID-19 knowledge increased, the team evolved and expanded to other infectious diseases of concern. The name was changed from the COVID-19 Response Team to the COVID-19 and Infectious Diseases Reference Team (CIRT). The CIRT will continue to meet as COVID-19 and other infectious diseases remain present, still causing potential serious illness.

OHCOW Impact

By creating an infectious disease recognition and prevention team, OHCOW has been at the fore front of providing information and recommendations for illness prevention to the workers of Ontario.

Resource: Relative Efficiencies of Different PPE

A thumbnail image of an OHCOW bar graph depicting the relative efficiencies of masks and respiratorsA bar graph created from peer-reviewed data that shows the relative efficiencies of various types of masks / respirators – from ineffective gaiters and cloth masks to surgical masks (with and without fit-braces), to fitted and non-fitted N95 respirators to highly effective elastomerics.




Messaging on Airborne Precautions

Spreading Information to Prevent Infection

OHCOW has continued through 2022 – 23 to provide clear and evidence based guidance towards safe practices for indoor air quality. Through webinars and virtual online conversations with Canadian and international experts, OHCOW continues to educate and promote public awareness of the need for clean air in both public and private spaces. The importance of preventing exposure to aerosol transmissible diseases ATDs including COVID-19 is stressed, in addition to providing tools and important guidance. The library of publicly available OHCOW COVID-19 resources is growing.

Dr. Howard Nioo, Deputy Chief Public Health Officer and Interim Vice-President Infectious Diseases Programs Branch Public Health Agency of Canada, recognized OHCOW’s results in providing public health information and guidance in September of 2022, stating publicly “I would like to take this opportunity to acknowledge the work of OHCOW and the important contributions you are making to workplace safety by increasing awareness of health and safety issues, and promoting workplace prevention strategies.

Webinars with a Global Reach

World class experts who presented at Occ-Covid webinars and Occ-Covid Conversations included:

Covid Protection: Optimizing Schools Webinar Protecting Teachers and Students – Optimizing Ventilation in Older Schools / Buildings: Lessons from Australia
Science of Computational Fluid Dynamics (CFD) Workplace Case Studies in Ventilation – Directing Clean Air and Raising Awareness About the Science of Computational Fluid Dynamics (CFD)


OHCOW’s Occ-COVID 2022 Webinars addressed ventilation and clean air, respirators, preventing viral transmissions, and other related topics. This compliments the extensive materials such as the ventilation calculation tool and checklist and more developed the previous year.

The Importance of Clean Air in the Workplace

Commit to C.A.R.E. is a public awareness campaign with a mission to level the playing field of understanding of environmental strategies to combat COVID-19 and other airborne viruses like measles and tuberculosis. The goal of the Commit to C.A.R.E. website is to provide access to science-based information about infectious diseases and how to reduce their spread in the workplace. It shares safe and practical action plans and recommendations to prevent disease transmission. Clean air is more important than ever given increasingly transmissible variants plus increased air pollution risk due to climate change.

OHCOW has teamed up with the American Industrial Hygiene Association (AIHA) and the Integrated Bioscience and Built Environment Consortium (IBEC) to encourage workplaces to Commit to C.A.R.E. (Community, Awareness, Responsibility and Equity): leveling the playing field to understand environmental strategies to combat COVID-19 and other airborne viruses like measles and tuberculosis.

The June 2022 Occ-Covid Webinar series featured content addressing the C.A.R.E. program.

 OCC-COVID Webinar Series: Cleaning the Air and Committing to C.A.R.E.

Advocating for Safer Diesel Legislation in our Underground Mines

The current Occupational Exposure Limit in Ontario for Diesel Particulate is set at a dangerously high level. This poses an unacceptable occupational disease risk to thousands of mine workers who are being exposed.
USW Local 6500 has partnered with the Center for Research in Occupational Safety and Health (CROSH) to combine advocacy with applied research. The Diesel Particulate Project’s objective is to provide education and awareness to our mine workers and their families to create meaningful change in our underground mines. Our team consists of occupational health and safety experts, researchers, labour activist, occupational hygienists, and worker compensation representatives.
Our mission is simple, bring the Occupational Exposure Limit for Diesel Particulate in Ontario to a safe, scientifically recommended level.

Diesel Exhaust Lung Cancer Relative Risk Calculator

The calculator can be used as a guide to communicate the risk from DEE exposure and lead to prevention.

Webinar: Diesel Exhaust Exposure – Influencing Change

In this webinar, Part of the Occ/tober 2022 Webinar Series, learn how workers and researchers are influencing change to reduce DEE exposures in Mining through the Diesel Particulate Project. The International Agency for Research on Cancer (IARC) has concluded that Diesel Engine Exhaust (DEE) is a cause of lung cancer (Group 1: carcinogenic to humans). CAREX Canada (2022). Approximately 966,000 Canadians are currently exposed to diesel engine exhaust at work. Potential next steps through tool development and continuing analysis of additional data/evidence will also be discussed.


  • Sean Staddon, WSIB Worker Representative, United Steelworkers Local 6500;
  • Dr. Sandra Dorman, Ph.D., Centre for Research in Occupational Safety and Health (CROSH);
  • Tobias Mankis, Science Communication Officer, CROSH
  • Dr. Kevin Hedges, Ph.D., Occupational Hygienist, OHCOW.

This video by Sonia Lal and James Miuccio details the hazards and proper PPE wear and precautions to use when working with granite and its particulates. The basics are covered with regards to the mineral itself, silica, the health hazards and how we can implement controls.

Presenters: James Miuccio, Occupational Hygienist, CIH, CRSP; and Sonia Lal, Occupational Hygienist, CIH, CRSP

Silica Control Tool Pilot Program for Construction Industry

OHCOW has created a new and improved web page about Silica, and an Infographic in the works.

The British Columbia Construction Safety Association (BCCSA) has developed the Silica Control Tool™ as a resource for the construction industry in BC. The Tool assists workplaces in conducting appropriate risk assessments and implementing effective controls and safe work practices where RCS dust may be an occupational hazard. Through the compilation of data relating to RCS dust exposures pertaining to various materials, tools and tasks in construction, the Tool can predict the expected exposures to workers under similar conditions.

The BCCSA, in partnership with the Occupational Health Clinics for Ontario Workers (OHCOW) and the Canadian Centre for Occupational Health and Safety (CCOHS), intends to provide access to the Silica Control Tool to a limited number of Ontario workplace parties for a period of 12 months starting in 2021. The intent of this exercise is to provide Ontario employers an opportunity to utilize the Silica Control Tool, the associated data, and its outputs. The Silica Control Tool will help Ontario workplaces, in assessing risk of exposure to RCS dust in the workplace and in developing control plans to help minimize exposure.

The pilot will be funded by the Occupational Health Clinics for Ontario Workers (OHCOW) and access to the Tool will be provided in partnership with the BCCSA and the Canadian Centre for Occupational Health and Safety (CCOHS).