Emissions of harmful substances to air

The Canadian Environmental Sustainability Indicators (CESI) program provides data and information to track Canada's performance on key environmental sustainability issues. These indicators track human-related emissions to air of 3 substances (mercury, lead and cadmium) and facility-based emissions to air of 1 substance (arsenic). The 4 substances are defined as toxic under the Canadian Environmental Protection Act, 1999. For each substance, data are provided at the national, regional (provincial and territorial) and facility level, and by source. Global emissions data are also provided for mercury. The indicators inform Canadians about emissions of mercury, lead and cadmium to air from human activity and emissions of arsenic from facility-based reporting in Canada. These indicators also help the government to identify priorities and develop or revise strategies to inform further risk management and to track progress on policies put in place to reduce or control these 4 substances and air pollution in general. Information is provided to Canadians in a number of formats including: static and interactive maps, charts and graphs, HTML and CSV data tables and downloadable reports. See the supplementary documentation for the data sources and details on how the data were collected and how the indicator was calculated.

Canadian Environmental Sustainability Indicators: https://www.canada.ca/environmental-indicators

Data and Resources

Additional Info

Field	Value
Last Updated	April 17, 2026, 17:55 (UTC)
Created	April 17, 2026, 17:55 (UTC)
contact_email	indicateurs-indicators@ec.gc.ca
contact_person	{}
criticality_level	[]
data_dictionary	[]
geographic_scope	["0"]
open_canada_collection	primary
open_canada_date_published	2025-08-28 00:00:00
open_canada_keywords	{"en": ["Atmospheric emissions", "Environment", "Air", "Toxic substances", "Air pollution", "Environmental indicators", "environmental indicators", "water", "pollution", "releases", "harmful substances", "toxic substances", "substances", "sources", "mercury", "Hg", "lead", "Pb", "cadmium", "Cd", "arsenic", "As", "toxic metals", "toxic", "Canadian Environmental Protection Act", "CEPA"], "fr": ["Émissions atmosphériques", "Environnement", "Air", "Substance toxique", "Pollution atmosphérique", "Indicateur environnemental", "indicateurs environnementaux", "indicateur environnemental", "eau", "pollution", "rejets dans l'eau", "substances nocives", "substances toxiques", "substances", "sources", "mercure", "Hg", "plomb", "Pb", "cadmium", "Cd", "arsenic", "As", "métaux toxiques", "toxiques", "Loi canadienne sur la protection de l'environnement", "LCPE"]}
open_canada_subject	["nature_and_environment"]
sensitivity_level	unrestricted
title_fr	Émissions atmosphériques de substances nocives
update_frequency	as_needed