July 20 (Reuters) - Canadian National Railway Co on Tuesday reported a rise in quarterly revenue and profit that was broadly in line with estimates as a North American economic recovery boosted freight volumes at the country's biggest railroad operator.

The Montreal-based company benefited in particular from rising industrial production as it shipped more petroleum, chemicals, metals and minerals. Revenue from automotive shipments nearly doubled as auto manufacturing facilities opened and demand recovered.

"We're quite confident about the broad economic recovery," Chief Financial Officer Ghislain Houle said in a conference call, while reaffirming the company's full-year results forecast.

However, Canadian National lost two weeks of shipments across a "critical bridge" on a route to Vancouver due to wildfires in the British Columbia area and said the situation remained "fluid." It did not quantify any hit to earnings but said traffic averages about 25 trains a day on the Kamloops and Boston Bar route.

Labor costs rose 23% in the quarter to $692 million, as companies continued to pay more to hire workers amid a shortage.

Canadian National's total revenue rose 12.1% to C$3.598 billion ($2.84 billion) in the three months ended June 30 versus average analyst expectations of C$3.66 billion, according to IBES data from Refinitiv.

Operating ratio, a key profitability metric for Wall Street, improved to 61.6% from 75.5% a year earlier.

Net income rose to C$1.03 billion, or C$1.46 per share, from C$545 million, or C$0.77 per share, a year earlier.

On an adjusted basis, profit was C$1.49 per share, in line with expectations.

Canadian National has agreed to buy smaller U.S. railroad Kansas City Southern for $33.6 billion, and the planned merger is being scrutinized by regulatory authorities.

($1 = 1.2674 Canadian dollars) (Reporting by Abhijith Ganapavaram in Bengaluru; Editing by Devika Syamnath)