The City of Toronto has no legal authority to force a contractor to reduce dust emissions on non-residential construction sites. If you have concerns about construction dust on a residential property, please refer to: Bylaw enforcement - dust from residential construction
If the commercial construction site has a building permit issued by the City of Toronto, contact the district Toronto Building Inspection office for the area where the construction site is located. A Building Inspector can visit the site and request that the dust be kept down (this does not include dust from landscaping work i.e cutting stone or concrete)
If the site is not one where a City of Toronto Building Permit was issued (i.e. landscaping sites where interlocking or stonework is taking place), Toronto Building cannot become involved.
Air Quality in Ontario
Poor air quality comes from a number of factors, including emissions from various natural and man-made sources (e.g. forest fires, vehicles, power plants, industrial processes and residences), and is influenced by atmospheric and weather conditions. You may contact the Ministry of the Environment, Conservation and Parks at the Duty Desk or the Ministry of Labour (from the standpoint of worker safety).
For health concerns related to dust, contact Toronto Health Connection
Air quality (health) complaint - dust - Port Lands
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