The Ford government is boosting the province's powers to slap fines on industry for breaking Ontario's environmental rules, but environmental activists say there's an important catch that actually weakens protections against air pollution.

This month, changes took effect giving provincial environmental officers wider scope to issue fines for such violations as emitting excess sulphur dioxide, a toxic compound typically released by oil refineries. The maximum fine is now $200,000, double the previous limit.

The government pitches this as part of Premier Doug Ford`s promise to "come down heavy" on polluters.

However, an environmental watchdog group says the increase in fines is outweighed by a separate move that allows refineries to pollute more.

Last fall, the province quietly changed a regulation under Ontario's Environmental Protection Act to exempt sulphur dioxide "flaring" incidents at petroleum refineries from meeting the province's air quality standards.

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Flaring incidents — in which refineries burn off excess crude oil products that cannot be processed — emit large quantities of sulphur dioxide in a short period of time. The flaring rules had been tightened by the previous Liberal government in March 2018.

"My guess is heavy industry lobbying, that they didn't like the changes that had been made to the law just before the last government left," said Elaine MacDonald, healthy communities director for Ecojustice, a Toronto-based environmental law charity.

Sulphur dioxide (SO2) emissions are a "serious health concern," said MacDonald, especially for people with respiratory problems such as asthma. She said flaring incidents can cause acute breathing problems for people nearby

"The reality is right now there's no air quality standard that applies to the flaring of acid gas at refineries," said MacDonald in an interview.

"So communities are vulnerable to spikes and high concentrations of sulphur dioxide from facilities flaring acid gas. And there's no enforcement that can be done to prevent that from occurring, because they've just exempted that completely."

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Imperial Oil owns the two largest refineries in Ontario, at Sarnia and Nanticoke. Two others in Sarnia are owned by Suncor and Shell.

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