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For multi-year queries, the 'Top {0}' refer to the Top {0} for the most recent year.

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    Facilities report the amounts of each pollutant they have released to the environment at their own location (on site). They also report how much of the substance was sent off-site for disposal, or transferred for recycling or other waste management. Each country's PRTR has evolved with its own list of pollutants, sector coverage, and reporting requirements. For more information, see : Understanding Taking Stock


        City (Select a State/Province/Territory to choose from a list of Cities)
          Watershed Based on its reported location, each facility has been assigned a watershed from the Watersheds dataset in CEC’s North American Environmental Atlas.
          • Note that there are Level III watersheds only in the Mississippi River System (i.e., Mississippi Sub-Basins).


            Pollutant Type
                • Values reported in pounds are converted to kilograms using a conversion factor of 2.205
                • Values reported in tonnes are converted to kilograms using a conversion factor of 1000

                Units of Measurement

                Each country requires PRTR reporting by facilities in specific industrial sectors or undertaking specific industrial activities. Click here for more information.

                Canada, Mexico and the United States have adopted the North American Industry Classification System (NAICS), whose codes are used to categorize the industrial activities of a facility. Although there is some variation among the three countries in the subsector categorizations and codes used, the breakdown of industrial sectors into general categories is the same:

                NAICS codeIndustry
                11Agriculture, forestry, fishing and hunting
                21Mining, quarrying and oil and gas extraction
                22Utilities (electricity, water and gas distribution)
                41/42/43Wholesale trade
                44/45/46Retail trade
                48/49Transportation and warehousing
                51Information and cultural industries
                52Finance and insurance
                53Real estate and rental and leasing
                54Professional, scientific and technical services
                55Management of companies and enterprises
                56Administrative and support, waste management and remediation services
                61Educational services
                62Health care and social assistance
                71Arts, entertainment and recreation
                72Accommodation and food services
                81Other services (except public administration)
                91/92/93Public administration

                PRTR reporting requirements are based in part on the industrial activity undertaken within a facility, and not only the industry code assigned to that facility. Therefore, not all facilities within a given sector might have to report. For example, within the economic sector that includes dry-cleaning only those facilities undertaking the actual dry-cleaning process, and not clothing drop-off points, might be required to report. Another example is a food processing plant that is required to report because it has its own power plant to generate electricity.

                Readers should also note that facilities with similar activities can report under different, or multiple, NAICS codes, depending on the activities undertaken at the facility.

                Taking Stock Online provides data at the 3-, 4- and 5-digit NAICS code level. In some cases, the North American Industry Classification System (NAICS) codes differ among the three countries. For example, the code for Wholesale Trade is 41 in Canada, 42 in the United States and 43 in Mexico. When querying data for an industrial sector whose code begins with any of the 2 digits below, the results returned might include only partial data. Therefore, you might also wish to consult the data reported under the corresponding codes provided.

                Industrial Sector NameCorresponding Codes in each Country
                (for the series starting with the 2 digits indicated)
                CanadaMexicoUnited States
                Wholesale Trade414342
                Retail Trade44, 454644, 45
                Public Administration919392

                North American Industry Classification System (NAICS)

                  * With certain exceptions, Canadian facilities reporting an on-site release of less than one tonne are not required to report the specific medium of the release (e.g., to air, water). Therefore, the NPRI “total onsite release” amount might not equal the sum of the individual on-site release categories.

                  ** Quantities of metals reported as transferred off-site for sewage, treatment, or energy recovery are included in the "Off-site Disposal" category, since these metals may be captured and removed from waste and disposed of in landfills, or by other methods. This approach recognizes the physical nature of metals and the fact that they are not likely to be destroyed through treatment.

                  The data are taken from the US Toxics Release Inventory, the Canadian National Pollutant Release Inventory (NPRI), and the Mexican Registro de Emisiones y Transferencia de Contaminantes (RETC). Each country has its own list of mandatory pollutants. Reporting thresholds for pollutants, sectors and facilities also vary. For details, see Understanding Taking Stock.

                  The national PRTR datasets are constantly evolving, as facilities revise previous submissions to correct reporting errors or make other changes. For this reason, the three countries 'lock' their data sets on a specific date and use the 'locked' data for annual summary reports. Each year, the countries issue revised databases that cover all reporting years. The CEC follows a similar process. For the purposes of this database, the NPRI dataset from December 2018, the TRI Basic Data Plus dataset from April 2019 and the RETC dataset from December 2018 were used. Readers can visit the national PRTR websites to see if any changes to the data have occurred.