A retired federal researcher based in Saskatoon is going public with concerns Ottawa is muzzling scientists like her.

Marley Waiser, 59, spent more than 25 years with Environment Canada, most recently with the National Water Research Institute in Saskatoon.

She retired last year, about a year after CBC News did a story about pollution in Regina's Wascana Creek that referenced her research.

In an interview, she says she wasn't allowed to talk to a CBC reporter about that story, but now wants her voice heard.

"I was reticent to come forward for fear of losing my job, or the repercussions," she said.

Waiser wrote two scientific papers for Environment Canada that were published in 2011 that looked at chemical pollutants (such as phosporus and ammonia) and pharmaceuticals (such as trace antibiotics) in Wascana Creek.

Both kinds of pollution were found downstream of the Regina sewage treatment plant west of the city.  

Waiser says when CBC contacted her to talk about the research, Environment Canada higher-ups lowered the boom.  

'One of the first things they said after reading the two papers on Wascana Creek is that they didn't want to upset the City of Regina.'—Retired federal scientist Marley Waiser

"One of the first things they said after reading the two papers on Wascana Creek is that they didn't want to upset the City of Regina," she said.

Waiser was told that she needed media training before she could talk to reporters about her research.

She says she wanted to get that and followed up with her supervisors, but the training was never arranged. Essentially, she was foiled not by a direct order not to talk, but by bureaucratic roadblocks, she said.

It's unfortunate for Canadians, she said, because they can benefit hearing first-hand from scientists studying the environment.

"We need to take care of our aquatic ecosystems," she said.

Environment Canada declined a recorded interview, but in an email, a spokesperson said the department won't comment on "hearsay."

The department says its researchers are encouraged to publish their work and civil servants are not muzzled.

Meanwhile, the office of Information Commissioner Suzanne Legault says it will be investigating similar claims involving seven government institutions, including Environment Canada and the Treasury Board.

(With files from Dani Mario)