NEW WESTMINSTER, B.C. -- A massive fire that began Sunday night in New Westminster could take weeks to extinguish.

And that is a big concern, say health officials, who worry smoke from the fire will cause already poor air quality to deteriorate even further.

“There’s an index to assess air quality and at this point, it is off the charts essentially at the highest level it can be…this fire on top of that essentially just added insult to injury,” explained Dr. Aamir Bharmal, a medical health officer with Fraser Health.

The region has already been experiencing poor air quality due to wildfires south of the border.

Fraser Health has issued an advisory to residents of New Westminster and surrounding communities about fine particulate matter in the air.

In addition to particulate matter, there is concern about the creosote that covers the pier’s pilings which are burning at the Westminster Pier Park.

“Creosote is a wood preservative made up of a mixture of chemicals. Short-term exposure to creosote may cause further respiratory irritation,” says a news release from Fraser Health.

Residents are being told to limit all strenuous outdoor activity and keep windows closed.

About 25 firefighters continue work to extinguish the blaze.

“The fire’s approximately three acres in size right now, fully involved underneath the decking of the pier,” explained New Westminster Fire Chief Tim Armstrong.

“It’s going to be a long, slow process and probably weeks (to extinguish it),” he said.

The fire department is using a drone with a thermal imaging camera to get a better handle on where the fire is still actively burning beneath the pier.

“That footage will be able to show us where the fire is the hottest… Right now it’s kind of a guessing game as to where the fire is and where it’s travelling,” Armstrong said.

The fire has forced the closure of some businesses, including Suna Studios.

“It’s a little frustrating, but it’s understandable,” says Rob Leishman who is with the studio and says roads to the business have been blocked.

“It’s been a really hard roll. Initially at the beginning of COVID, we shut down the studios for two months. We got back up. Now this is happening here,” he told CTV News.

New Westminster resident Carolyn McLaughlin says the fire has been quite upsetting.

“It felt very apocalyptic…we were all just basically in tears and scared,” she recalls.

She says the loss off the city’s iconic “W” on the waterfront “…is just devastating. Not just the loss of this whole (art) piece but the historical aspect of it.”

The cause of the fire is under investigation by both New Westminster police and the fire department.