New Brunswick

Premier ready to ban glyphosate if link found to mystery brain illness

Premier Susan Holt says her government would be willing to ban the herbicide glyphosate if a new investigation finds a link to the purported mystery brain illness that a Moncton neurologist says he is tracking.

Premier says residents fear herbicide's impacts; federal scientist says it isn't showing up in harmful amounts

A woman in a sweater poses for a photo
The results of a provincial investigation into the mystery brain illness could result in a glyphosate ban if a link is found, said Premier Susan Holt. (Michael Heenan/CBC)

Premier Susan Holt says her government would be willing to ban the herbicide glyphosate if a new investigation finds a link to the purported mystery brain illness that a Moncton neurologist says he is tracking.

The province has launched a new investigation into the hundreds of cases, saying the symptoms have sparked fear among many New Brunswickers that needs to be addressed.

"New Brunswickers are afraid about what glyphosate might do, and the mysterious neurological illness has given them reason to be more afraid," Holt said in a year-end interview with CBC News.

"So we have to make sure that we know exactly what that chemical is doing, and where and when."

If a link is found, "then we need to eliminate that exposure for New Brunswickers." 

But Holt emphasized the idea was hypothetical because "we don't have good science to tell us that that is what's making New Brunswickers sick."

Glyphosate is used in agriculture and in industrial forestry operations.

Major logging companies use it to thin some forms of forest vegetation near the ground so young trees get more sun and rain and have a better chance to grow.

A helicopter flying above a forest spraying a liquid
Glyphosate is used to thin vegetation by some forestry and agricultural companies in New Brunswick. (James Steidle/CBC)

Its impact on human health has been debated in New Brunswick for more than a decade, and Holt noted activists have focused their lobbying on the forest sector.

"There's a curious distinction that's being made from folks who accept it in agriculture but don't accept it in forestry," she said.

A 2023 study by the Canadian Forest Service collected 296 samples in watersheds where glyphosate had been applied and detected the herbicide in only one of them.

That single sample was measured at 17 parts per billion — far below the threshold for safe drinking water of 280 parts per billion.

Even that threshold would require someone to drink water with that amount of glyphosate "every day for their entire life" for there to be a risk to their health, said Chris Edge, the lead research scientist on the study.

"What I think the body of work that we've done now has shown is that glyphosate is present in the environment, but is present at concentrations that are lower than where we'd expect adverse effects to occur," he said. 

According to Edge, glyphosate binds to soil and sediment. That, plus the ban on spraying it when it's windy and the required buffer areas near rivers, make it unlikely the herbicide will reach a watershed.

A man in a jacket poses for a photo
Chris Edge, the lead researcher on a 2023 study, said glyphosate is present in the environment but at low levels. (Jacques Poitras/CBC)

Another study he conducted found levels of glyphosate in vegetation dropped below the risk threshold 18 days after spraying — and wildlife would have to eat that vegetation, with that amount of glyphosate, for their entire lives to become ill.

Moncton neurologist Dr. Alier Marrero has suggested that glyphosate has contributed to blue-green algae blooms that can emit toxins that affect the brain.

Edge says algae can feed on phosphate molecules in glyphosate, "but for that to work, glyphosate would have to be present in the rivers," and his study found only that one sample.

"So [it's] theoretically plausible, but in reality we're not detecting glyphosate, so it's unlikely to be leading … to cyanobacteria blooms."

Edge said his research was funded entirely by the federal government and was not paid for or supported by the forest industry.

Sarah Nesbitt, one of Marrero's patients whose urine samples showed levels of glyphosate, said she believes the herbicide and a mix of other environmental factors contributed to her illness.

WATCH | 'We need to eliminate that exposure': Holt on mystery illness:

Holt could ban glyphosate if link to mystery illness is found

7 hours ago
Duration 3:18
Premier Susan Holt says she’ll act, if a new investigation finds there’s a connection between neurological symptoms and the herbicide.

Nesbitt says she started experiencing symptoms after aerial forestry spraying near her home in Steeves Mountain near Moncton.

She welcomed the new provincial investigation.

"Everything they said they were going to do, they've done, so I have to give them that," she said.

In 2021, officials from J.D. Irving Ltd., the province's largest forestry company, told a committee of MLAs that banning glyphosate would be "disastrous" and fears about it were not science-based but sprang from misinformation circulating on social media.

Researchers were constantly looking for better ways to thin vegetation but "the alternatives are really challenging," said the company's director of science Andrew Willett.

"We will not stop trying to find alternative ways. But today, this is the most effective way to deal with that early vegetation."

A woman in a tee shirt poses for a photo
Sarah Nesbitt is one of Dr. Marrero's patients, and said she belives glyphosate is one of the factors of her illness. (Chris Monetta/CBC)

Holt told CBC News that glyphosate is already "a heavily controlled substance that comes with processes of regulation and certification," and the government could look at further restrictions on how it's used.

In an earlier interview with CBC News on the mystery brain illness, Holt said some patients were concerned because "we know the kind of lobby that exists to support the continued use of that chemical." 

In the year-end interview on Dec. 9, she said that comment was a reference to manufacturers of the herbicide that are "in regular contact" with Health Canada to ensure regulators continue allowing it to be sold in Canada.

She said it was not a reference to lobbying by J.D. Irving Ltd.

"I haven't been lobbied personally on this," she said.

The previous Progressive Conservative government concluded in 2022 that the cases Marrero diagnosed didn't have a common cause.

"No such syndrome exists," then-Health Minister Dorothy Shephard said at the time.

Holt's health minister, Dr. John Dornan, told CBC News last week he didn't want to say definitively yet whether there is a single neurological illness.

"I wouldn't speculate on that. I think the fact that it's been raised means that it's possible," said Dornan.

"It would be, I think, naive and inappropriate for me as an individual, or as a physician, or as a New Brunswicker to say yes, or no there isn't. I think we need a more thorough review of the data."

That patient data is now being collected as part of the new investigation, he said.

ABOUT THE AUTHOR

Jacques Poitras

Provincial Affairs reporter

Jacques Poitras has been CBC's provincial affairs reporter in New Brunswick since 2000. He grew up in Moncton and covered Parliament in Ottawa for the New Brunswick Telegraph-Journal. He has reported on every New Brunswick election since 1995 and won awards from the Radio Television Digital News Association, the National Newspaper Awards and Amnesty International. He is also the author of five non-fiction books about New Brunswick politics and history.

With files from Kayla Hounsell