VANCOUVER -- More smoky, hazy air is expected to blanket much of Metro Vancouver and the Lower Mainland today as nearly 600 wildfires continue to rage across British Columbia.

Metro Vancouver announced Sunday it would continue a previous air quality advisory because of the high levels of fine particulate matter, which doctors say can be absorbed into the blood stream and lungs, causing exhaustion and confusion.

Massive clouds of choking smoke from the wildfires has prompted air quality advisories for much of Western Canada and also forced the cancellations of two triathlons in B.C.'s Okanagan region on Sunday.

The fires burning near the Nadina, Shovel and Tesla lakes in the Bulkley-Nechako region remain the largest in the province at more than 1,600 square kilometres combined.

But BC Wildfire Service crews were able to make some headway over the weekend, as weather conditions allowed them to burn fuel in the path of the infernos.

Meanwhile, thousands of kilometres to the southeast, 4,500 residents of Kimberley, B.C., have been on an evacuation alert since Thursday as smoke continues to descend on the East Kootenay region.

The wildfires sweeping across B.C., the world’s biggest exporter of softwood lumber, have sparked a rally in prices. Lumber futures rose almost 10 per cent last week and West Fraser Timber’s stock has rallied in eight straight sessions.

With files from BNN Bloomberg