Do border workers have a higher cancer risk? 2 unions, Ontario workplace research centre team up for a study

Two unions and the Occupational Cancer Research Centre are following up on previous research on whether Canadian border employees have an elevated cancer risk due to exposure to environmental pollutants — something workers have long been concerned about.

The study, involving the Public Service Alliance of Canada (PSAC) and the Customs and Immigration Union (CIU), is set to begin later this year.

Due to their long-term daily exposure to freight truck emission fumes, workers — including Alissa Howe, who was at the Ambassador Bridge in Windsor, Ont., for 27 years — have long questioned a connection. Howe is now president of the CIU's Windsor branch.

Alissa (Lisa) Howe, president of Windsor Branch 18 of the Customs and Immigration Union, worked as a border services officer for 27 years, mainly at the Ambassador Bridge. (Photo provided by Alissa Howe)

"I, as well as many employees, believe that there may be a correlation to the exposures in the workplace and the rates of cancer we are seeing," Howe said in a statement.

"I have witnessed the two previous studies that were conducted on breast cancer amongst my co-workers, active and retired. We have lost a lot of good people to this awful disease. We are excited to see where the science will take us."

The two unions will fund the upcoming feasibility study, which will examine whether there's an elevated cancer risk for people working at ports of entry across Canada. Further details on the study have yet to be released.

The World Health Organization and the International Agency for Research on Cancer have identified diesel exhaust as a known carcinogen.

Jane McArthur, the toxics program director at the Canadian Association of Physicians for the Environment, felt there was a gap in how the media spoke about breast cancer when she set out to write her 2021 doctoral thesis. It looked at the disease among women who worked at the Ambassador Bridge.

Jane McArthur, now the toxics program director at the Canadian Association of Physicians for the Environment, wrote her doctoral thesis on women who were diagnosed with breast cancer and had worked at the Ambassador Bridge. (Photo provided by Jane McArthur)

"When we talk about breast cancer, we don't talk about environmental or workplace exposures," McArthur said. "We tend to focus on lifestyle or genetic factors. [It] puts the blame on the individual for their cancer and ignores exposures they have no control over."

Canada Border Services Agency (CBSA) said it won't comment on third-party research. However, it did contract an industrial hygienist for an air quality assessment in June 2019 that found "the levels of all chemicals were below the Occupational Exposure Limits, even during peak traffic periods."

"Should new information become available that suggests a need to review past health and safety findings, the agency will not hesitate to do so," CBSA said in a statement.

Commercial traffic bound for Detroit via the Ambassador Bridge is shown in this file photo. Diesel fuel and vehicle emissions have fuelled some border workers' fears about their health. (Darrin Di Carlo/CBC)

McArthur believes acknowledging environmental risk factors in the workplace is a huge step.

For her dissertation, she collected the stories of 25 women who worked at the Ambassador Bridge, which connects Windsor and Detroit and is North America's busiest border crossing. Many of the women preferred not to be named out of fear for their job security.

"The stories were reflective of their lack of power to control their exposures, but also their attempts to address what they intuitively knew: The volume of the trucks at the bridge was likely a contributor," McArthur said.

In 2018, the Workplace Safety and Insurance Appeals Tribunal (WSIAT) dismissed an appeal from a female CBSA customs officer at the bridge crossing. She had been diagnosed with breast cancer twice — in 2001 and 2007 — after working for some 20 years.

According to the decision summary, the panel "found that scientific evidence was not sufficient to support a relationship between diesel fumes or automotive exhaust and the worker's breast cancer."

The WSIAT said there were other risk factors, including the worker's childhood exposure to chemicals at her family farm and diagnoses of cancer among four other members of her family.

Jim Brophy co-authored a report on breast cancer among workers at the Ambassador Bridge. (Jonathan Pinto/CBC)

Researchers Michael Gilbertson and Jim Brophy examined that worker's compensation case in 2019 and were able to identify a "cluster" of cases, inclusive of the worker involved in the appeal.

According to the research, there were six to eight instances of breast cancer among 135 female workers between December 1999 and June 2002. Gilbertson and Brophy also found that women who worked at the bridge were 16 times more likely to develop breast cancer compared to women in data from the surrounding Essex County.

"I think that's what we would call a sentinel event," Brophy said. "Statistically, it's an anomaly for sure."

Gilbertson, who worked with the federal government for 34 years to develop the Environmental Contaminants Act, said the case was a "serious injustice."

He believes the findings should be considered when it comes to the current construction of the Gordie Howe International Bridge, which is expected to open sometime next year, and working to reduce potential environmental harms.

Michael Gilbertson, an academic researcher who specializes in environmental toxins and health, studied cancer rates at the Ambassador Bridge when compared to Essex County in 2018. (Josiah Sinanan / CBC News)

"You're now building [a new] bridge, an enormous expense. And here we are with this extraordinary observation," Gilbertson said of his 2019 findings.

McArthur has her own ideas that could contribute to reducing potential environmental dangers in the future.

"[Maybe] some different mitigating factors such as green spaces [near the bridge] that might scrub some of the air pollutants, or pollution control measures on the trucks — that kind of thing."

The Gordie Howe bridge will connect Ontario to Michigan over the Detroit River, west of the Ambassador Bridge and Detroit-Windsor Tunnel. (Michael Evans/CBC)

Have you or know someone you know been given a cancer diagnosis and suspect it may be connected to a workplace environment? Send your story to josiah.sinanan@cbc.ca.