COMMISSION FOR ENVIRONMENTAL COOPERATION
THREE COUNTRIES WORKING TOGETHER TO PROTECT OUR SHARED ENVIRONMENT
The pollutants subject to national PRTR reporting requirements are listed because they meet certain criteria for chemical toxicity and the potential for risk to human health and the environment. Each PRTR system covers a specific list of substances: NPRI spans over 300 pollutants, TRI approximately 600 and RETC 104.
As of April 2006, the Chemical Abstracts Service (CAS) listed more than 27 million chemical substances and identified more than 239,000 of them as regulated or covered by chemical inventories worldwide.
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. Pollutant-based reporting thresholds exist, and certain pollutants have lower reporting thresholds due to their greater potential for risk to human health and the environment. In general, the PRTR pollutant thresholds are as follows:
For more info, see Mandatory pollutants common to at least 2 of the 3 North American PRTRs [Excel - 85KB].
In order to provide more information about PRTR pollutants, the Taking Stock report and online database also categorize them as follows:
Toxic Equivalency Potentials (TEPs) indicate the relative human health risk associated with a release of one unit of a pollutant, compared to the risk posed by the release of one unit of a reference substance. TEPs are calculated using the CalTOX model, developed by California regulatory agencies. TEPs are one of many different screening tools, each of which is based on a series of assumptions, thus yielding different results.
Readers should note that the TEP analysis is limited in that a release does not directly correlate to actual exposures or levels of risk. In addition, not all of the substances have an assigned TEP (information on their toxicity or exposure potential may be missing). While these pollutants are not ranked by TEP, they should not be assumed to be without risk. Other types of releases not ranked by TEP (e.g., land) should also not be assumed to be without risk.
TEPs are available only for air and water releases. The reference chemical for carcinogens is benzene and the reference chemical for non-carcinogens is toluene. In the Taking Stock report and database, the TEP weight is multiplied by the amount of release to provide a score for each pollutant. The TEPs for Taking Stock have been taken from the Scorecard website.
Each country requires PRTR reporting by facilities in specific industrial sectors or undertaking specific industrial activities.
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. NAICS codes were established in 1997 and since 2006 they have been incorporated into PRTR reporting to replace the standard industrial classification (SIC) codes used by each country. 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. For more information about the implementation of the NAICS system in each country, see:
NAICS code Industry
11 Agriculture, forestry, fishing and hunting
21 Mining, quarrying and oil and gas extraction
22 Utilities (electricity, water and gas distribution)
41/42/43 Wholesale trade
44/45/46 Retail trade
48/49 Transportation and warehousing
51 Information and cultural industries
52 Finance and insurance
53 Real estate and rental and leasing
54 Professional, scientific and technical services
55 Management of companies and enterprises
56 Administrative and support, waste management and remediation services
61 Educational services
62 Health care and social assistance
71 Arts, entertainment and recreation
72 Accommodation and food services
81 Other services (except public administration)
91/92/93 Public 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.
Both NPRI and TRI have an employee threshold, generally corresponding to the equivalent of 10 full-time employees (with some exceptions for pollutants or certain types of facilities). Mexico's RETC does not have an employee threshold.
More information on reporting instructions is available on the NPRI, RETC and TRI websites: