Lambton County discrediting a study about increased leukemia in Sarnia

I don’t usually write about this topic, but I think this is important for friends and family in my hometown of Sarnia.

The front page of The Sarnia Observer today has an article in which the Lambton County medical officer of health, Dr. Sudit Ranade, questions a research study finding that Sarnia, which is in Lambton County, has higher incident rates of a type of leukemia.

He critiques the research on the topic of age differences:

“The biggest problem with the work they have done is that they have not accounted for the difference in age between different populations,” Ranade said.

People are more likely to get cancer when they’re older, but there are ways of using data to account for age differences between locations, he said.

“These authors didn’t do that,” Ranade said. “What they’re really doing is comparing apples to oranges instead of apples to apples, and that’s a big problem in this kind of research to not standardize by age.”

But Ranade is misrepresenting the article, because the researchers definitely accounted for age in their study. I can only guess why a medical officer would want to discredit an article that shows a potential health hazard in his county.

In the article, the researchers explain that age difference had been explored:

These results highlight that, although the populations living in Sarnia […] were older when compared with Ontario […] or Canada […], these differences alone could not account for a significantly (>3‐fold) higher incidence rate reported in these communities. [I left out the specific numbers]

“This analysis confirms that the incidence/mortality rates [from this type of leukemia] in Sarnia are significantly higher than the national average despite normalization by age.

You might wonder why I care that the medical officer of health is publicly challenging the results of this study. Every scientific study is just a single glimpse into the world. This one found something about Sarnia that could impact people’s lives, even if it is only remotely possible.

Sarnia, St. Catharines, Hamilton, Sault Ste Marie, and Thunder Bay are all high-incidence areas in Ontario. [Image from original article]

The researchers point out the importance of these findings in their conclusion:

In conclusion, this important epidemiological study highlights potential AML case clustering in Sarnia and other industrial cities in Ontario. Our future detailed analysis of exposures in these cities will likely confirm existing risk factors and may reveal novel ones for AML. This report also presents a call to action to limit exposure to certain chemicals through the ubiquitous installation of high‐efficiency particulate air filters in these AML high‐incidence cities. [emphasis added]

People living in Sarnia should be aware of these kinds of findings and be able to push for improvements that could spare their lives. The medical officer’s position is defensive rather than concerned, protective of his work rather than open to new information that could help the region.