Summary of stakeholders comments on the proposed 2025-2027 NPRI reporting requirements

Introduction

In 2022, the National Pollutant Release Inventory (NPRI) drafted a work plan for the 2025-2027 NPRI reporting requirements with input from a multi-stakeholder work group. The work plan included a list of potential changes to the NPRI for which Environment and Climate Change Canada (ECCC) would develop consultation documents and conduct consultation periods. The work group discussed work plan items via teleconference and at in-person meetings during 2022 through 2024.

This document outlines the changes we have made to NPRI reporting requirements beginning with the 2025 reporting year. The final 2025-2027 requirements were published in Part I of the Canada Gazette on March 8, 2025. This document describes the new requirements, summarizes the corresponding comments received from stakeholders during consultation periods, and provides our response to those comments. For each of the proposed changes, input was solicited from stakeholders and the public.

Contact the NPRI at inrp-npri@ec.gc.ca for a PDF version of this document.

Chemicals Management Plan substances

The NPRI Multi-Stakeholder Work Group provided input on our proposal to make the following changes to reporting requirements beginning with the 2025 reporting year:

Benzothiazoles

• Remove the individual listing for 2-mercaptobenzothiazole (MBT; Chemical Abstracts Services Registry Number [CAS RN] 149-30-4) from Part 1, Group A of the NPRI substance list 
• Add a group of 20 benzothiazoles (including MBT) to Part 1, Group B of the NPRI substance list with a 100-kilogram manufacture, process, otherwise use (MPO) threshold and a 0.1% concentration by weight threshold. The thresholds were proposed to apply to the cumulative total of the 20 substances, rather than applying to each substance individually.

Cyanides

• Add a group of nine substances called “free cyanide, cyanide salts and cyanide complexes” to Part 1, Group B, with a 1 000 kg manufacture, MPO threshold and 0.1% concentration by weight threshold. The MPO thresholds were proposed to apply to the total of the group of substances, rather than applying to each substance individually.
• Move hydrogen cyanide (CAS RN 74-90-8) from Part 1, Group A, to Part 1, Group B and reduce the MPO threshold from 10 tonnes to 1 000 kg and 0.1% concentration.

Long-chain aliphatic amines

• Add of a group of 92 long-chain aliphatic amines (LCAAs) with a manufacture, process or otherwise use threshold of 5,000 kilograms and a concentration threshold of 0.1% by weight to Part 1, Group B. The MPO thresholds were proposed to apply to the total of the group of substances, rather than applying to each substance individually.

Triarylmethane dyes

• Add four triarylmethane dyes to Part 1, Group B, with a 100 kg MPO threshold and 1% concentration threshold. The MPO threshold was proposed to apply to each of the four substances individually.
• Move C.I. Basic Green 4 (CAS RN 569-64-2) from Part 1, Group A, to Part 1, Group B and reduce the MPO threshold from 10 tonnes to 100 kg and retain the 1% concentration threshold.
• Rename C.I. Basic Green 4 to Malachite Green to match the name it is proposed to be listed as in Schedule 1 of the Canadian Environmental Protection Act (CEPA).

After reviewing stakeholder input, we made the changes to requirements as described above with one modification: the benzothiazoles group will be listed with the name “benzothiazoles that can form 2-mercaptobenzothiazole.” There has been no change to the CAS RNs that are covered under this group of substances.

Comments were received from the following stakeholders:

• Canadian Vehicle Manufacturers’ Association 
• Fertilizer Canada
• Forest Products Association of Canada 
• Mining Association of Canada 

Summary of stakeholder comments and our response related to benzothiazoles, cyanides, long-chain aliphatic amines and triarylmethane dyes

1. Access to information and administrative burden

Stakeholder comments

• Concerns about the lowered concentration threshold, as Safety Data Sheets (SDS) do not contain information for substances that are not identified as carcinogens at concentrations lower than 1%.
• Requesting information from suppliers is not reasonable and sets an unrealistic expectation for further data collection.

Our response

Facilities are required to use information that they possess or that they may reasonably be expected to have access to when reporting to the NPRI. As such, it may be appropriate that facilities contact suppliers for more information or take other steps (e.g., conduct source testing) to fulfill their reporting obligations. 

The previous 1% concentration threshold was not resulting in appropriate reporting by Canadian industry. Based on a review of available data, a lower threshold (0.1%) has been deemed appropriate.

2. Chemical Abstracts Services Registry Number (CAS RN)

Stakeholder comments

Specific CAS RNs provide certainty, clarity, and consistency for reporting facilities and data users. CAS RNs should be provided with NPRI reporting requirements. Without defined CAS RNs, information gathering is more difficult, and data quality can be impacted.

Our Response

We recognize that CAS RNs are important for reporting facilities and data users and includes CAS RNs with substance listings where possible. The applicable CAS RNs for reporting have been identified in the Gazette Notice and will be included in any accompanying reporting guidance.

Summary of stakeholder comments and our response regarding the proposed changes related to cyanides

1. Other mechanisms for collecting data

Stakeholder comments

ECCC should consider if NPRI is the appropriate method for collecting data on hydrogen cyanide if or the needs of data users could be met using a different mechanism (e.g., a notice issued under section 71 of the Canadian Environmental Protection Act (CEPA)).

Our response

Surveys issued under section 71 of CEPA generally apply to a single year, do not always require reporting of releases, the results are not made public and access to the data within the government is restricted.

Ongoing data collection and public availability are key features of the NPRI. There are no other public Canada-wide sources of pollutant release information. There is interest in using data on releases of hydrogen cyanide on an ongoing basis from various users both within and outside government, making NPRI an ideal mechanism for collecting and publishing this information.

2. Analytical methods and administrative burden

Stakeholder comments

• Information should be collected for the “free cyanide, cyanide salts and cyanide complexes” group broadly, and not for speciated substances. Weak acid dissociable (WAD) analysis is the preferred test method, as it aligns with current analytical/commercial practice, would build on existing datasets that include WAD data, and would simplify the analytical work needed to meet this new NPRI reporting requirement.
• ECCC should consider the analytical capabilities at commercial laboratories and sampling and analytical costs of total cyanide analysis as part of a cost-benefit analysis.

Our response

When reporting to the NPRI, facilities can select from a variety of estimation methods, only one of which is source testing. Facilities that rely on SDS to estimate and report to the NPRI should search by specific CAS RN to find the relevant information.

Summary of stakeholder comments and our response regarding the proposed addition of long-chain aliphatic amines

1. Zero releases

Stakeholder comments

These substances are often used in closed loop systems, which means there are no releases to the environment and would be nothing to report.

Our response

Reports must be submitted for all NPRI substances that are manufactured, processed or otherwise used at or above the stated threshold, even if there are no releases to air, water, land, disposed or recycled. Reports of zero releases are still valuable information because they can inform communities of the presence of substances on-site that may not be released during normal operations but may be released during an accident or other atypical event.  

1. Reporting confidential information

Stakeholder comments

Reporting on confidential volumes of substances is not in the best interest of facilities.

Our response

The manufactured, processed, and otherwise used values are a trigger to determine if the facility meets the requirements and are not disclosed to ECCC. Facilities are not required to report these quantities. Instead, facilities are required to report the quantity of the substance that is released, disposed of, or transferred from the facility.

Summary of stakeholder comments and our response regarding the proposed addition of triarylmethane dyes

1. Duplication of reporting and administrative burden

Stakeholder comments

ECCC should consider if NPRI is the appropriate method for collecting data on triarylmethane dye releases if the needs of data users could be met using a different mechanism (e.g., Guideline for the Reduction of Dyes Released from Pulp and Paper Mills).

Our response

Reporting under a Guideline generally applies to a single year and only when thresholds are exceeded. The data collected under this mechanism are not made public and is limited to specific activities. In addition, there are stipulations that may limit annual reporting under the Guideline if standards are being respected. 

Ongoing data collection and the public availability of the data are key features of the NPRI. There are no other public Canada-wide sources of pollutant release information. There is interest in using data on releases of triarylmethane dyes on an ongoing basis from various users both within and outside government, making NPRI an ideal mechanism for collecting and publishing this information.

2. Misinterpretation of NPRI data

Stakeholder comments

Without context, NPRI data can be misinterpreted.

Our response

We have published a Guide for Using and Interpreting NPRI Data on the NPRI website.

The NPRI continues to engage ECCC sector experts to develop tools, guidance, and other context to accompany the published NPRI data. Facilities can also provide context for their reported data in their submission using the comment fields within the online reporting system. 

Per- and polyfluoroalkyl substances (PFAS)

Prior to the consultation period, we created a sub-group to gather information and form recommendations for changes to be made to the NPRI reporting requirements regarding PFAS. Solicitation of members for this sub-group was done by contacting the NPRI Multi-Stakeholder Work Group members and observers, including representatives of the reporting community, civil society organizations, Indigenous governments and organizations, academia and individuals. Nominations were considered by us and priority was given to nominations that represented a broad constituency that would be impacted by NPRI reporting and public disclosure of PFAS. NPRI, ECCC and Health Canada representatives provided information to and engaged in discussions with the Sub-group over the course of a year. Based on available information, the Sub-group reached common ground on a list of criteria for selecting PFAS to be listed on NPRI, but did not reach common ground on other issues (e.g., at what level the mass and concentration threshold should be set). We accepted the list of criteria as the starting point for PFAS reporting in the NPRI, and then selected the mass and concentration threshold based on data on uses of PFAS in the US and Europe (Canadian data were not available) and SDS disclosure rules. 

The Final report and recommendations of the MSWG Sub-group to consider the addition of PFAS to the National Pollutant Release Inventory for the 2025-2027 Gazette Notice details the process, the information that was analyzed, the common ground and the divergent views of Sub-group members. It is available on request from inrp-npri@ec.g.ca.

The Multi-Stakeholder Work Group provided input on our proposal to add reporting requirements for per and polyfluoroalkyl substances (PFAS) to the NPRI beginning with the 2025 reporting year:

We proposed to add reporting requirements for 131 individual PFAS and their salts to the NPRI. Each PFAS was proposed to be required to be reported by any facility that manufactures, processes, or otherwise uses 1 kilogram or more of that PFAS at a concentration of 0.1% by weight or more. PFAS were proposed to be added to a new Part 1, Group C.

After reviewing stakeholder input, we made the following changes to requirements: 163 PFAS have been added to a new Part 1, Group C of the NPRI substance list – the 131 PFAS that were proposed, and 32 specific salts of PFAS identified during consultations. Each PFAS is required to be reported by any facility that manufactures, processes, or otherwise uses 1 kilogram or more of that PFAS at a concentration of 0.1% by weight or more. 

The following table summarizes the comments received during consultations on changes related to PFAS and presents our response to those comments. Comments were received from the following stakeholders:

Summary of stakeholder comments and our response regarding the proposed addition of PFAS

1. Substance list

Comment and response 1

Stakeholder comments:

Support for or agreement with the proposed list.

Our response:

We thank stakeholders for taking the time to consider the proposed changes.  

Comment and response 2

Stakeholder comments:

• Concerns with the “and its salts” qualifier. 131 substances may not reflect the actual number of substances if the “salts” must also be reported. This increases the potential reporting burden by an unknown amount. This could cause compliance issues. 
• The list of PFAS should be clear and manageable. It should be a complete list of reportable individual substances and salts, with distinct CAS RNs.

Our response:

For those PFAS acids that were proposed to be listed with the qualifier “and its salts,” the qualifier has been removed. We have now listed 32 specific salts that need to be reported separately. Reporting is limited to the 163 specifically listed PFAS and additional PFAS salts do not need to be reported.

Comment and response 3

Stakeholder comments:

ECCC’s proposed approach of reporting on individual PFAS rather than the class of PFAS will not provide a full picture of the releases and transfers associated with the full class of PFAS. It will not account for the life cycle of PFAS including those PFAS that may transform or degrade to other PFAS. Data on releases of only a selected number of individual PFAS will not give an accurate understanding of the cumulative effects of total PFAS releases. A proposed alternative approach is to require reporting of PFAS as a class, as well as some selected individual PFAS, either starting in 2025, or starting in 2028, and to allow the use of measures like total organic fluorine (TOF) which can provide a qualitative assessment of PFAS presence to fulfill a community right-to-know need.

Our response:

PFAS are a class of as many as 15,000 substances. NPRI currently requires that about 300 substances be reported, and it is not feasible to start requiring the reporting of thousands of additional substances individually. It is also not feasible to list PFAS as a class or an aggregate total since there are currently no methods that could be used to measure or estimate “total PFAS” for reporting to the NPRI. Analytical methods currently exist that can measure a small number of individual PFAS only. Other methods can be used to report to the NPRI (e.g., emission factors, mass balance, and engineering estimates), but these function on an individual substance basis as well. 

Methods such as total organic fluorine (TOF), total fluorine (TF), or total oxidizable precursors (TOP) are used as indicators to estimate PFAS presence and do not provide data on actual releases and transfers of PFAS. They are not available for all media, might be costly (total oxidizable precursors), and are not suited to any of the accepted methods for reporting to the NPRI, except source testing. Therefore, We have not added the class of PFAS to the NPRI. Methods for measuring PFAS are continuously being developed and if a quantitative method for measuring total PFAS is developed, we can reconsider adding the entire class of PFAS to the NPRI at that time. 

Comment and response 4

Stakeholder comments:

Listed PFAS should allow for reasonably reliable information to be reported and the PFAS should be relevant to the Canadian context.

Our response:

The list of PFAS was selected based on four criteria, described in the consultation document, with the addition of 32 salts. These criteria are based on some of the common ground found by the PFAS Sub-Group and were accepted by us as the starting point for PFAS reporting in the NPRI, and included criteria regarding the Canadian context.

Comment and response 5

Stakeholder comments:

Focus on the highest risk PFAS; use a toxicity index similar to the one for dioxins and furans.

Our response:

Information on the relative risk of individual PFAS is not currently available, so it was not feasible to use a relative risk-based approach to selecting PFAS for NPRI reporting.

Comment and response 6

Stakeholder comments:

• Start with a small number of PFAS allowing substances to be added progressively as advances in research and technology support the addition of more substances.  
• PFAS reporting outcomes should be monitored, with a clear process for removing substances as appropriate.

Our response:

We chose 131 PFAS out of thousands based on four criteria, described in the consultation document, with the addition of 32 salts. These criteria are based on some of the common ground found by the PFAS Sub-Group and were accepted by us as the starting point for PFAS reporting in the NPRI. We will continue to monitor the evolution of scientific understanding of PFAS and will consider adding new substances or removing substances from the list. 

Comment and response 7

Stakeholder comments:

For some PFAS on the list the columns for reporting rationale are blank. More info needed on these.

Our response:

There are two possible explanations for this: 

1. Trifluoroacetic acid (76-05-1) appears on the list because it was identified as a priority by stakeholders (selection criterion #4) even though it did not meet any of the first three selection criteria. There is no column to indicate “stakeholder priority” in the table in Appendix A of the consultation document since only one substance out of the list of 131 substances met this criterion.   
2. In some cases, only the acid or anionic form of a PFAS met one or more criteria for selection. In these cases, the missing form of the PFAS was added to the proposed list in order to capture both forms. For example, perfluorododecanesulfonic acid (79780-39-5) appears on the proposed list even though it does not meet any of the four selection criteria. However, the anionic form perfluorododecanesulfonate – 343629-43-6) meets the “detected in Canada” criteria, so the acid form (79780-39-5) was also added to the proposed list.  

Comment and response 8

Stakeholder comments:

Apply the OECD definition as the primary criterion for deciding on which PFAS to list.

Our response:

According to the OECD 2021 definition, as many as 15,000 substances can be classified as PFAS. We needed to narrow this list in order to make reporting feasible. The list of PFAS was narrowed based on four criteria, described in the consultation document, with the addition of 32 salts. These criteria are based on some of the common ground found by the PFAS Sub-Group and were accepted by us as the starting point for PFAS reporting in the NPRI. All of the PFAS that are listed in the NPRI meet the OECD 2021 definition.

Comment and response 9

Stakeholder comments:

Include PFAS precursors in aqueous film-forming foam (AFFF) and other precursors.

Our response:

There are some PFAS precursors on the proposed NPRI list (e.g., TFA). The individual PFAS precursor substances are not generally measured by laboratories, making it difficult for some facilities to report. Addition of other precursors can be considered in the future.

Comment and response 10

Stakeholder comments:

Include fluoropolymers.

Our response:

Fluoropolymers are a distinct class of PFAS with fluorines directly attached to carbon‐only backbone polymer, high molecular weight, and unique properties. Although fluoropolymers fit the PFAS structural definition, they have very different physical, chemical, environmental, and toxicological properties when compared with other PFAS. However, fluoropolymers were not intentionally excluded from NPRI consideration. The four selection criteria developed by the PFAS Sub-Group and accepted by NPRI coincidentally screened out any fluoropolymers.

Comment and response 11

Stakeholder comments:

Do not include PFOS and PFOA, which are prohibited, and LC-PFCAs, which are proposed for prohibition.

Our response:

The list of PFAS was selected based on four criteria, described in the consultation document, with the addition of 32 salts. These criteria are based on some of the common ground found by the PFAS Sub-Group. 

In Canada, PFOS, PFOA, and LC-PFCAs (and their salts and precursors) are partially prohibited under the Prohibition of Certain Toxic Substances Regulations, 2012, with a limited number of exemptions (such as certain AFFF fire-fighting foams and photolithography and photographic film). Due to past activities and their presence in manufactured items, these PFAS can still be found in or released to the environment, and it is therefore important to track releases through the NPRI.

Comment and response 12

Stakeholder comments:

Exclude polymeric PFAS.

Our response:

The list of PFAS was selected based on four criteria, described in the consultation document, with the addition of 32 salts. Based on these criteria, polymeric PFAS are included in reporting requirements.

Comment and response 13

Stakeholder comments:

Some of the substances proposed for addition are not on the Domestic Substance List (DSL) or Non-Domestic Substances List (NDSL). As such, they may not be in commerce in Canada and the requirement to report them to the NPRI may create confusion. 

Our response:

The DSL and NDSL have thresholds for substances to be included. Although these thresholds are low, it is possible that certain PFAS that are not on the DSL or NDSL are entering commerce in Canada in quantities lower than DSL/NDSL thresholds but higher than the 1 kg NPRI threshold.

2. Reporting thresholds

Comment and response 1

Stakeholder comments:

Support for or agreement with the proposed changes.

Our response:

We thank stakeholders for taking the time to consider the proposed changes. 

Comment and response 2

Stakeholder comments:

Align PFAS requirements with an existing Part and Group instead of creating a new Part and Group.

Our response:

Due to the extensive list of PFAS, their unique properties and their continuous evolving science and regulations, we have created a new Group C under Part 1 of the NPRI substance list for PFAS. Aside from the mass and concentration thresholds, the requirements under Group C will be the same as for Group B.   

Comment and response 3

Stakeholder comments:

• Many comments were received that the proposed 1kg and 0.1% thresholds were too low and would result in additional reporting burden with little perceived benefit. 
• Many comments were received that the proposed 1kg and 0.1% thresholds were too high and would not result in comprehensive enough reporting.

Our response:

Two of the guiding principles of the NPRI, established in the 1992 Final Report of the Multi-Stakeholder Advisory Committee, are that the coverage should be comprehensive and that the data should present as complete a picture as possible of the sources of releases of NPRI substances. An additional guiding principle states that reporting to NPRI should be made as simple as possible and not unreasonably burden facilities.  

We consider available information when establishing a reporting threshold for a substance being added to the NPRI while trying to find a balance between data comprehensiveness and reporting burden. PFAS are known to be used and released, and to have health and environmental consequences in small quantities at low concentrations, necessitating low reporting thresholds. Based on information available at this time (US and European use and release data described in the consultation document), we expect that the 1 kg and 0.1% concentration thresholds are appropriate for PFAS. The threshold can be revised in the future if it becomes clear that it is too high or too low.

Comment and response 4

Stakeholder comments:

Consider existing SDS disclosure requirements when selecting a threshold for PFAS.

Our response:

We took into consideration the SDS disclosure requirements of 1% for hazardous materials and 0.1% for mutagenic, carcinogenic or toxic for reproduction substances when selecting the 0.1% concentration threshold for PFAS. Not all facilities will use SDS to report to the NPRI. For facilities using source testing, method detection limits are below 1% and 0.1% and a higher concentration threshold would exclude those results from being reported.

Comment and response 5

Stakeholder comments:

Align NPRI PFAS reporting requirements with US Toxics Release Inventory (TRI) PFAS reporting requirements, for the 63 PFAS that are common to both lists or for all PFAS.

Our response:

NPRI and TRI are similar in many aspects but there are also some necessary key differences. Starting in 2020, the United States Toxics Release Inventory (TRI) listed 172 individual PFAS with a manufacture, process, or otherwise use threshold of 100 lbs (approximately 45 kg) and concentration thresholds of either 0.1% for carcinogenic PFAS (only PFOS was identified as carcinogenic) or 1% for the remaining PFAS. New PFAS have been added to the TRI list each year since 2020 and for the 2024 reporting year, 196 individual PFAS substances are listed. Also in 2024, the concentration threshold was removed since it was identified as a barrier to comprehensive reporting. The TRI is able to use a much higher mass threshold than the NPRI 1kg threshold since PFAS are deliberately manufactured in the US but there is no known deliberate manufacture in Canada. PFAS are expected to be incidentally manufactured as by-products in very small quantities or processed or otherwise used in very small quantities in Canada. 

PFAS are known to be used in small quantities at small concentrations and given the health and environmental concerns associated with PFAS, and in order to minimize the complexity that different PFAS thresholds would cause, we have implemented the 1 kg manufactured, processed or otherwise used and 0.1% concentration by weight threshold as proposed.

Comment and response 6

Stakeholder comments:

Given that the reporting thresholds for the US TRI are higher than what is being proposed for NPRI, the proposed threshold could be increased without endangering human health or the environment. There is no risk assessment benefit to using a threshold lower than the TRI threshold.

Our response:

TRI and NPRI thresholds are not based on an assessment of risk, they are based on known or expected manufacture, process or otherwise use quantities. These quantities are expected to be much lower in Canada than the US, necessitating a lower NPRI threshold.

Comment and response 7

Stakeholder comments:

NPRI should not implement a concentration threshold for reporting of PFAS, especially since the concentration threshold was determined to be a barrier to comprehensive reporting to the TRI.

Our response:

We have chosen to align the NPRI concentration threshold with SDS disclosure requirements at this time. There is not enough evidence at this time to have no concentration threshold. Based on an analysis of the impact of removing the concentration threshold on TRI reporting and of s. 71 reporting, the concentration threshold can be revised in the future if needed.

Comment and response 8

Stakeholder comments:

Remove the employee threshold for reporting of PFAS.

Our response:

The employee threshold is based on the principle that the NPRI should not pose an unreasonable burden on facilities, particularly small facilities that may not have the resources to report, nor the technical expertise to report quality data. NPRI has removed the employee threshold in the past (e.g., for dioxins and furans) but only when there is clear evidence to justify it. There is no clear evidence at this time that the employee threshold will be a barrier to comprehensive reporting and that facilities with fewer than 10 employees will be able to report. Therefore, we are retaining the employee threshold for reporting of PFAS.

Comment and response 9

Stakeholder comments:

Implement a "trigger one, report all" approach to reporting of PFAS, i.e., if the threshold is met for at least 1 PFAS, all NPRI-listed PFAS should be required to be reported.

Our response:

There is no demonstrated connection between the individual PFAS listed on NPRI and therefore no reason to believe that if one is present, any others are also present. This approach could be reconsidered in the future if evidence of connections is found.

Comment and response 10

Stakeholder comments:

The following statement in section 4.3 of the consultation document is inaccurate: “The concentration threshold does not apply to by-products, i.e., substances that are by-products must be included in threshold calculations regardless of concentration. Once the concentration threshold is met, all releases and transfers must be reported regardless of concentration.”

Our response:

We regret the error. A more detailed explanation is:   A facility must calculate the quantities of a substance that are manufactured, processed or otherwise used in order to determine if they are required to report. When doing these threshold calculations, the facility only needs to include those quantities of a substance that meet the reporting threshold, unless the substance is a by-product, in which case the concentration threshold does not apply. Once a facility has determined that they meet the threshold, all quantities of the substance that are released, disposed of or transferred for recycling must be reported, regardless of the quantity or concentration of the release, disposal or transfer.

Comment and response 11

Stakeholder comments:

Use standard alternate thresholds when selecting a threshold other than 10 tonnes to reduce complexity. For PFAS, align with existing alternate thresholds.

Our response:

We can consider a standard alternate threshold in future requirements. The thresholds for Part 1B substances that have been selected in the past have been selected based on specific circumstances for each substance or group of substances (e.g., a risk management objective or known manufacture, process or otherwise use quantities). While this increases the complexity, it allows for thresholds lower than 10 tonnes and higher than the lowest Part 1B threshold (1kg) where warranted. A standard alternate threshold might necessarily need to align with the lowest mass and concentration thresholds (currently 1kg for ethylene oxide and 0% for mercury).

Comment and response 12

Stakeholder comments:

Do AFFF containing PFAS deployed on site need to be reported?

Our response:

Any manufacture, process or otherwise use of PFAS at a facility may need to be reported if thresholds are met, including PFAS contained in AFFF. If thresholds are met, the quantities of PFAS that are released, disposed of and recycled will need to be reported, but the total quantities of AFFF deployed on site to not need to be reported.

3. Implementation year

Comment and response 1

Stakeholder comments:

Support for requiring reporting of PFAS beginning in 2025.

Our response:

We thank stakeholders for taking the time to consider the proposed changes.  

Comment and response 2

Stakeholder comments:

• Do not require reporting on PFAS until at least 2026 to allow reporting facilities more time to prepare and to allow industries and regulators to develop and adopt standardized practices to identify PFAS.  
• Use a phased implementation approach, gradually increasing the number of PFAS that are required to report. 
• Do not require reporting of PFAS in NPRI until the final State of PFAS Report and Risk Management Approach are published. 
• Wait to see if the US election will result in changes to PFAS reporting in the TRI and then align with the new TRI requirements. 
• Wait to see if the Canadian election will result in a change of priorities.

Our response:

We understand that facilities need time to prepare in order to properly report and that 2025 data quality may suffer as a result of the requirements being published part way through the first year to which they apply. Facilities are required to use information that they possess or that they may reasonably be expected to have access to when reporting to the NPRI. Facilities need to demonstrate due diligence and comply with the requirements to the best of their ability, despite the timing of the requirements.

NPRI considered a phased approach to reporting but there were no suitable criteria with which to divide the list of PFAS into groups. In addition, the use of a phased approach would increase the complexity of the reporting requirements and could potentially cause confusion for reporting facilities and data users.

If NPRI waits to implement reporting requirements for PFAS until after the final State of PFAS Report and Risk Management Approach are published, or until the results of one or more elections are known the next NPRI notice will apply to calendar years 2028-2030. The dangers of PFAS have been known since as early as the 1950s. Adverse environmental and health effects have been observed for well-studied PFAS and they have been shown to pose a risk to the Canadian environment, therefore NPRI considers its actions proactive. Potential future adjustments to the NPRI list are possible as new information about PFAS are emerging.  

Comment and response 3

Stakeholder comments:

Publish reporting requirements in advance of the year to which they apply, to avoid significant impacts on data quality.

Our response:

We aim to publish reporting requirements before the first year to which the reporting requirements apply. Although this timing has not always been possible, We are working to improve the timeliness of NPRI notices, which is part of the intent of moving to a three-year cycle. We understand that the delayed publication of the 2025 PFAS requirements may result in reduced data quality for 2025.

Comment and response 4

Stakeholder comments:

Defer requirements for some of the proposed PFAS until CAS numbers are identified.

Our response:

We have provided 163 CAS RNs for specific PFAS that need to be reported.

Comment and response 5

Stakeholder comments:

Add PFAS beyond the proposed list starting in 2026. 

Our response:

The NPRI is intended to evolve and expand over time to respond to new needs. The list of 163 PFAS will be reviewed once several years of data have been collected in order to determine if more or different PFAS need to be listed and to determine if any of the listed PFAS should be removed. It will be too early to undertake this analysis in time to make any changes for 2026.

4. Access to information required to report

Comment and response 1

Stakeholder comments:

• Some facilities are required to rely on suppliers and SDS for information they need to report to NPRI. Many suppliers and SDS do not disclose information on PFAS either because concentrations are below SDS disclosure thresholds or because they treat the information as confidential/proprietary. 
• Facilities should not be expected to conduct source testing for PFAS that are not included on SDS. 
• Information on PFAS in materials that are disposed of/recycled is not always available.

Our response:

Information on releases, disposals and transfers for recycling needs to be reported if the owner/operator possesses the information or may reasonably be expected to have access to the information. The NPRI Notice specifies that if emissions are already monitored or measured under provincial or federal legislation or a municipal bylaw, those measurements must be used to report to the NPRI. Otherwise, facilities can choose the most appropriate basis of estimate to report to the NPRI based on their particular circumstances. In deciding whether additional efforts should be undertaken to generate new information for the purposes of NPRI reporting (e.g., contacting suppliers for more information, conducting source testing), the following factors, among others, should be considered:

• the health and environmental risks posed by a substance, including whether the substance has been declared toxic under CEPA
• the relative contribution of the industrial sector to releases, disposals and transfers for recycling of a substance in Canada
• the relative contribution of the facility to releases, disposals and transfers for recycling of a substance in Canada
• the cost of additional monitoring

Comment and response 2

Stakeholder comments:

Facilities should be allowed to use the information contained in SDS of products as part of the process of identifying PFAS for reporting to the NPRI.

Our response:

Facilities are allowed to use SDS information for the purposes of reporting to the NPRI.

Comment and response 3

Stakeholder comments:

• Not all PFAS are able to be measured using current analytical methods. Not all identified analytical methods are available to facilities using commercial/accredited labs. 
• Some types of facilities should only be required to report PFAS for which an analytical method exists and is commercially available.

Our response:

Facilities are not required to use source testing to report to the NPRI. For listed PFAS for which an analytical method does not exist or for which a method does exist but is not available to the reporting facility, the facility can use one of eight remaining acceptable methods of estimation. Facilities that do use source testing will not be able to measure and report quantities of all the NPRI-listed PFAS due to the limitations of current analytical methods. Those facilities may report only on those PFAS covered by a specific method or may be able to use other methods of reporting for those PFAS that are not covered.

Comment and response 4

Stakeholder comments:

ECCC should provide a specific reporting process for PFAS contained that have confidential CAS RNs.

Our response:

None of the NPRI-listed PFAS have confidential CAS RNs.

Comment and response 5

Stakeholder comments:

ECCC should specify that the U.S. estimates already made for the purpose of reporting to the US TRI can be used by Canadian companies for the purpose of reporting to the NPRI.

Our response:

Facilities in Canada can opt to use the same methods that their US counterparts use to report to the TRI but will need to keep in mind the differences in reporting thresholds.

Comment and response 6

Stakeholder comments:

• Available emission factors or monitoring data may not accurately represent releases or transfers associated with specific facilities.  
• It is not appropriate to use release estimates from one facility to estimate releases from another facility.

Our response:

Facilities should only be using carefully selected emission factors that they have detailed information about, and that are applicable to the sources and processes at their facility. 

5. Increase in time and resources required to report to NPRI 

Stakeholder comments

Many comments were received that the proposed changes would increase the time and resources needed by facilities to report to the NPRI ("reporting burden"). 

Our response

Two of the guiding principles of the NPRI, established in the 1992 Final Report of the Multi-Stakeholder Advisory Committee, are that the coverage should be comprehensive and that the data should present as complete a picture as possible of the sources of releases of NPRI substances. An additional guiding principle states that reporting to NPRI should be made as simple as possible and not unreasonably burden facilities.  

We take both of these conflicting principles into account when considering any changes to NPRI reporting requirements. In some instances, the value of public disclosure of information is considered to outweigh the increase in time and resources required by facilities to report, e.g., the requirement for even small facilities subject to the Chromium Electroplating, Chromium Anodizing and Reverse Etching Regulations to report hexavalent chromium to the NPRI, regardless of the manufacture, process or otherwise use (MPO) threshold and the employee threshold. In other instances, the requirement to report is considered to be so burdensome that it could potentially cause financial hardships to small businesses and would not result in quality data being reported, e.g., the 10-tonne MPO and 20 000-hour employee thresholds that apply for tetrachloroethylene so that thousands of small dry-cleaning shops are not required to report.   

We continuously review NPRI reporting requirements, not just for opportunities to improve or increase reporting, but also to find ways to reduce the administrative burden of reporting. For example, under the ongoing Substance Review, NPRI has identified and deleted numerous substances in recent years that are low priority or that have low reporting. Facilities no longer have to track these substances, which results in a small reduction in burden.  

In the case of PFAS, We have determined that the value of public disclosure of releases of PFAS outweighs the increase in time and resources required by facilities to report to the NPRI. The broad use of PFAS and their consequent ubiquitous presence in the environment have resulted in continuous environmental and human exposure to multiple PFAS. As a result of the extreme persistence of PFAS, their potential for bioaccumulation in organisms and biomagnification through the food chain, their ability to move locally and over long ranges, and the difficulty of their removal from the broader environment, environmental concentrations and uptake by biota and humans will continue increase, making it particularly important to track their releases in a public inventory. We expect that there will be an increase in the time and resources required to report to the NPRI in the first year that the new requirements are implemented; however, ongoing costs are expected to be lower. 

6. NPRI exemptions and exclusions

Stakeholder comments

• Remove existing exemptions to increase reporting, specifically PFAS used in hydraulic fracturing and PFAS in pesticides. 
• Add exemptions to restrict reporting to decrease burden, specifically where no releases occur.

Our response

As mentioned in the previous response, NPRI reporting requirements are based on the balance between comprehensiveness of the data vs. the burden on reporting facilities. In general, the balance between these two principles is achieved through the use of thresholds and exclusions. We acknowledge that thresholds and exclusions do limit the comprehensiveness of the inventory, meaning that reported releases may not completely reflect actual releases, especially at small scales. However, it is our position that they are necessary to try and balance the value of the data against the time and resources required by industry to report those data.

We have considered the possible removal of and/or addition of exemptions or exclusions in the case of PFAS and has not implemented any changes. NPRI will be considering the exemption for hydraulic fracturing activities (for all substances) as part of a separate process. PFAS in pesticides are not explicitly exempt from reporting.  

Reports must be submitted for all NPRI substances that are manufactured, processed or otherwise used at or above the stated threshold, even if there are no releases to air, water, land, disposed or recycled. Reports of zero releases are still valuable information because they can inform communities of the presence of substances on-site that may not be released during normal operations but may be released during an accident or other atypical event.  

Data users can refer to the Guide for Using and Interpreting Data from the National Pollutant Release Inventory to understand the limitations caused by the use of thresholds and exclusions. 

7. Guidance and support

Stakeholder comments

• Guidance is needed for reporting facilities, including guidance specific for reporting of PFAS in AFFF.
• Guidance should be developed in consultation/collaboration with stakeholders.  
• Guidance should be developed prior to any NPRI reporting requirements being implemented for PFAS. 
• Guidance should be made available at or before the start of the first year to which reporting requirements apply. 
• Training sessions should be provided for reporting facilities on the new requirements.

Our response

A draft guidance document has been prepared by a consultant and we has provided stakeholders with an opportunity to review and comment on the document. The guide includes information specifically on PFAS in AFFF. It was not possible to develop guidance before the reporting requirements were published. We intend to publish the guide as soon as possible, but it was not possible to do so before the start of the first year to which the reporting requirements apply. We have taken note of the recommendation on timing for future guides. We intend to provide virtual training sessions to reporting facilities early in 2026, including information on how to report for PFAS as well as information on other changes to reporting requirements for 2025 reporting.

8. Data accessiblity and public communication

Stakeholder comments

Collaborate with stakeholders and experts to provide context to PFAS data and guidance on interpreting PFAS data, including an emphasis on the limitations of the data.

Our response

We intend to update the Guide for Using and Interpreting NPRI data to include contextual information on PFAS and a description of the limitations of the PFAS data, including information on the potential impacts on data quality of the delayed publication of the NPRI notice and guidance. We intend to publish a factsheet on PFAS once a few years of data have been collected, and stakeholders will have the opportunity to review and comment on it. Facilities can also provide context for their reported data in their submission using the comment fields within the online reporting system. 

9. Pollution prevention

Comment and response 1

Stakeholder comments:

Pollution prevention actions for PFAS should be reported separately from pollution control actions.  

Our response:

We acknowledge that there is disagreement that some of the activities NPRI lists as pollution prevention are in fact pollution control. Regardless of whether the activities are prevention or control, collecting information on those activities is still important. NPRI will not change the requirement to report them, but will consider ways to improve how the data is published, to make the distinction clearer.

Comment and response 2

Stakeholder comments:

Substitution of one PFAS for another PFAS should not be considered to be pollution prevention.

Our response:

We provide recommendations for facilities that substitute materials or feedstock do so with environmentally-friendly substitutions and efforts should be made to select PFAS-free alternatives. Facilities are required to specify what substitutions are made when reporting to the NPRI. More information on pollution prevention methods can be found on the Government of Canada website: How your business can prevent pollution - Canada.ca.

Comment and response 3

Stakeholder comments:

Pollution prevention reporting should be mandatory for PFAS.

Our response:

Pollution prevention reporting is mandatory for all NPRI-listed substances. When facilities submit reports with no pollution prevention activities, it can be assumed that no pollution prevention activities took place.

10. Consultation process

Stakeholder comments

More information is needed on the members of the PFAS Sub-group and the consultation process that was followed.

Our response

Solicitation of members for this sub-group was done by contacting the NPRI Multi-Stakeholder Work Group members and observers, including representatives of the reporting community, civil society organizations, Indigenous governments and organizations, academia and individuals. Nominations were considered by us and priority was given to nominations that represented a broad constituency that would be impacted by NPRI reporting and public disclosure of PFAS. NPRI, ECCC and Health Canada representatives provided information to and engaged in discussions with the Sub-group over the course of a year. Based on available information, the Sub-group reached common ground on a list of criteria for selecting PFAS to be listed on NPRI, but did not reach common ground on other issues (e.g., at what level the mass and concentration threshold should be set). We accepted the list of criteria as the starting point for PFAS reporting in the NPRI, and then selected the mass and concentration threshold based on data on uses of PFAS in the US and Europe (Canadian data were not available) and SDS disclosure rules. 

The Final report and recommendations of the MSWG Sub-group to consider the addition of PFAS to the National Pollutant Release Inventory for the 2025-2027 Gazette Notice details the process, the information that was analyzed, the common ground and the divergent views of Sub-group members. It is available on request from inrp-npri@ec.gc.ca.

11. Future changes

Stakeholder comments

• The work of the PFAS Sub-group should continue and future refinements to requirements should be considered. 
• ECCC should provide stronger leadership to ensure discussions remain focused on NPRI objectives, that the rules of engagement are followed, and that sufficient time is allocated for the work to result in a concrete proposal or set of proposals for MSWG consideration, rather than simply a summary of discussions. ECCC can look to establish a continuous feedback loop with industry stakeholders to address emerging issues and refine the reporting process over time. Continuing the PFAS Subgroup would also be beneficial to ensure continuity within the NPRI by maintaining a core of competence in the subgroup, keeping new stakeholders informed of past discussions, revisiting tabled conversations, and providing guidance on unresolved issues and future focus areas. 

Our response

The PFAS Sub-group fulfilled its mandate in June of 2024. Given limited resources and additional priorities, NPRI has established a Sub-group to address oil sands data quality issues, with work to take place over the course of 2025-2028 and will not have the resources to begin another PFAS Sub-group or continue the previous one. We will consider any suggestions on addressing future emerging issues regarding PFAS in consultation with the full NPRI Multi-Stakeholder Work Group.

12. Harmonization with other programs

Comment and response 1

Stakeholder comments:

Avoid reporting duplication with the section 71 notice on PFAS.

Our response:

There is very little overlap between the s. 71 Notice for PFAS and the NPRI. NPRI allows for continuous annual collection of data that is available to the public, in contrast to one-time s. 71 notices where the reported data are generally not made public. Section 71 notices generally collect data on quantities of substances that are imported/exported, manufactured, and used. NPRI collects data on quantities of substances that are released, disposed of, and recycled. Only 18 of the 163 NPRI PFAS are also listed in the s. 71 notice.

Comment and response 2

Stakeholder comments:

Harmonize and align with provincial government reporting requirements and avoid duplicating reporting.

Our response:

NPRI is Canada's national legislated public inventory of data on facility releases of pollutants. Requirements apply to all facilities in Canada equally. Provincial requirements can vary depending on specific circumstances and do not apply to the whole country. We have and will continue to review the requirements of other federal and provincial reporting programs in order to identify opportunities for harmonization in the future. 

13. General

Comment and response 1

Stakeholder comments:

The Government of Canada should use a class-based approach to assessing and managing the risks of PFAS.

Our response:

We are using a class-based approach to assess and manage the risks of PFAS, as reflected in the Draft State of PFAS Report and Risk Management Scope.

Comment and response 2

Stakeholder comments:

NPRI as a risk management or pollution control or reduction tool.

Our response:

NPRI was created to inform communities of substances that are present at and/or released from facilities in their neighborhoods. Its primary role is to serve a community right-to-know purpose by collecting and publishing facility-reported data. NPRI does not engage in risk management activities and listing a substance on NPRI is not considered to be risk management (although NPRI data often informs risk management). NPRI does not require pollution controls and does not directly result in reductions in pollutant releases (even though one of the stated objectives of NPRI is to encourage voluntary action to reduce releases). NPRI does not impose emissions limits (although NPRI data may be used to help determine regulatory limits).

Comment and response 3

Stakeholder comments:

NPRI is a mandatory reporting tool used by the Chemicals Management Plan and is subject to the Cabinet Directive on Regulation and must include an economic assessment.

Our response:

NPRI is a mandatory information gathering tool established under the authority of s. 46 of CEPA. NPRI is not a regulation, is not subject to the Cabinet Directive on Regulation and is not required to conduct a Regulatory Impact Analysis when making changes to requirements. NPRI is not a CMP tool, it is a community right-to-know tool that sometimes informs CMP activities.

Comment and response 4

Stakeholder comments:

Sources and sites of discharges known to the Government of Canada should be prioritized and information on them should be shared.

Our response:

For information on this, see the Draft State of PFAS Report.

Comment and response 5

Stakeholder comments:

Keep new stakeholders informed, provide guidance on unresolved issues and on future focus areas.  

Our response:

NPRI is planning a series of information sessions and learning opportunities for stakeholders throughout 2025 and 2026. For stakeholders interested in learning more about the NPRI, training materials are available on the NPRI website as well (NPRI 101 and 201)

Comment and response 6

Stakeholder comments:

NPRI should require facilities to report on quantities of substances that leave their facilities as or in products.

Our response:

NPRI has considered this recommendation, and the proposal on requiring reporting substances transferred off-site in or as products. Further consideration is deferred pending the development of a Government of Canada strategy for labelling of substances in products and proposed new requirements for consumer chemical products under the Canada Consumer Product Safety Act.

14. Comments received that are out of scope

Comment and response 1

Stakeholder comments:

Switch to Non-Animal Methods for all toxicology research and Federal Environmental Quality Guidelines.

Our response:

These comments are out of the scope of NPRI and have been forwarded to the relevant ECCC authorities.

Comment and response 2

Stakeholder comments:

Mandatory disclosure of CAS RNs and clear labeling are needed.

Our response:

A Government of Canada strategy for labelling of substances in products is being developed and proposed new requirements for consumer chemical products under the Canada Consumer Product Safety Act are underway. 

Comment and response 3

Stakeholder comments:

Improvements are needed to SDS disclosure rules.

Our response:

Health Canada administers the Hazardous Products Act (HPA) and the Hazardous Products Regulations (HPR), which collectively outline the supplier notification requirements, including hazard classification and hazard communication via the supplier label and SDS.  In the future, Health Canada may introduce more transparency in disclosure of hazardous consumer products on SDS. This may have implications for consumer products containing PFAS and listed as hazardous under the Hazardous Products Act. 

Ethylene oxide

The NPRI Multi-Stakeholder Work Group provided input on our proposal to make the following changes to the reporting requirements for ethylene oxide (CAS RN 75-21-8), beginning with the 2025 reporting year:

1. Reduce the MPO threshold from 10 tonnes to 1 kg and reduce the concentration threshold from 1% to 0.1%
2. Remove the exemption for reporting of ethylene oxide manufactured, processed or otherwise use for the purposes of education or training of students 

After reviewing stakeholder input, we made the changes to requirements as described above.

The following summarizes the comments received during consultations on changes related to ethylene oxide and presents our response to those comments. Comments were received from the following stakeholders:

Summary of stakeholder comments and our response regarding the proposed changes to the reporting requirements for ethylene oxide

1. Reporting threshold

Comment and response 1

Stakeholder comments:

Support for ECCC’s proposed changes to reporting thresholds for ethylene oxide to report on mass threshold of 1 kg and to require reporting from facilities involved in education and training of students.

Our response:

We thank stakeholders for taking the time to consider the proposed changes.

Comment and response 2

Stakeholder comments:

Mass and employee thresholds should be removed.

Our response:

Two of the guiding principles of the NPRI, established in the 1992 Final Report of the Multi-Stakeholder Advisory Committee, are that the coverage should be comprehensive and that the data should present as complete a picture as possible of the sources of releases of NPRI substances. An additional guiding principle states that reporting to NPRI should be made as simple as possible and not unreasonably burden facilities. 

We consider available information when establishing a reporting threshold for a substance being added to the NPRI while trying to find a balance between data comprehensiveness and reporting burden. We expect that the 1 kg and 0.1% concentration thresholds are appropriate for ethylene oxide. The threshold can be revised in the future if it becomes clear that it is too high or too low.

There is no clear evidence at this time that the employee threshold will be a barrier to comprehensive reporting and that facilities with fewer than 10 employees will be able to report. Therefore, We are retaining the employee threshold for reporting of ethylene oxide.

 

Comment and response 3

Stakeholder comments:

Questions about how the employee threshold applies to a facility with more than one building.

Our response:

NPRI reporting requirements apply to contiguous facilities. A contiguous facility is defined as all buildings, equipment, structures and stationary items that are located on a single site, or on contiguous sites or adjacent sites, that are owned or operated by the same person and that function as a single integrated site, including wastewater collection systems that release treated or untreated wastewater into surface waters.

2. Exemptions

Comment and response 1

Stakeholder comments:

The exemption for reporting of releases from education and training of students should not be removed.

Our response:

Given that facilities in the education sector (i.e. universities and colleges) make up a substantial proportion of the ethylene oxide authorized facilities in Ontario (and potentially in other provinces as well), We have removed the mass threshold calculation exemption for activities related to education or training of students. 

Comment and response 2

Stakeholder comments:

The exemption for reporting of releases for other sectors/activities should also be removed.

Our response:

The exemptions for reporting from other activities/sectors (e.g., research or development, repair or maintenance of vehicles) have not been removed. However, the threshold for ethylene oxide has been lowered for all other activities and sectors beyond those exempted.

3. Pollution prevention

Stakeholder comments

Facilities should be required to report ethylene oxide pollution prevention activities.

Our response

Pollution prevention reporting is mandatory for all NPRI-listed substances. When facilities submit reports with no pollution prevention activities, it can be assumed that no pollution prevention activities took place.

4. Access to information required to report

Comment and response 1

Stakeholder comments:

Used (empty) ethylene oxide ampules/cartridges used in sterilization units are not considered as special waste and are disposed of with regular garbage. No information is collected on the destination.

Our response:

Information on releases, disposals and transfers for recycling needs to be reported if the owner/operator possesses the information or may reasonably be expected to have access to the information. The NPRI Notice specifies that if emissions are already monitored or measured under provincial or federal legislation or a municipal bylaw, those measurements must be used to report to the NPRI. Otherwise, facilities can choose the most appropriate basis of estimate to report to the NPRI based on their particular circumstances. In deciding whether additional efforts should be undertaken to generate new information for the purposes of NPRI reporting (e.g., contacting suppliers for more information, conducting source testing), the following factors, among others, should be considered:

• the health and environmental risks posed by a substance, including whether the substance has been declared toxic under CEPA
• the relative contribution of the industrial sector to releases, disposals and transfers for recycling of a substance in Canada
• the relative contribution of the facility to releases, disposals and transfers for recycling of a substance in Canada
• the cost of additional monitoring

Comment and response 2

Stakeholder comments:

Emission monitoring technology may not be available.

Our response:

Facilities are not required to use source testing to report to the NPRI. Facilities can choose the most appropriate basis of estimate to report to the NPRI based on their particular circumstances.

5. Implementation year

Stakeholder comments

Extend the consultation period.

Our response

Given the timing of the publication of the Notice for 2025, we were not able to extend the consultation period. We understand that facilities need time to prepare in order to properly report and that 2025 data quality may suffer as a result of the requirements being published part way through the first year to which they apply. Facilities are required to use information that they possess or that they may reasonably be expected to have access to when reporting to the NPRI. Facilities need to demonstrate due diligence and comply with the requirements to the best of their ability, despite the timing of the requirements.

6. Comments received that are out of scope

Stakeholder comments

Switch to Non-Animal Methods for all toxicology research and Federal Environmental Quality Guidelines.

Our response

These comments are out of the scope of NPRI and have been forwarded to the relevant ECCC authorities.

Naphthenic acid fraction compounds

The updated definition is intended to clarify what must be reported and is not intended to result in a change to requirements and has been included in the 2025-2027 Gazette Notice.  The new  definition is as follows: 

Carboxylic acids that include chain compounds and compounds with one or more alicyclic ring structures with the general formula C_nH_2n+ZO_xN_αS_β, where “n” indicates the carbon number; “Z” is referred to as the “hydrogen deficiency” (the number of hydrogen atoms that are lost as the structures become more compact) and is zero or a negative, even integer (from -2 to -12); “x” refers to the oxygen number; “α” refers to the nitrogen number; and “β” refers to the sulphur number. Includes diverse polar organic compounds present in bitumen and oil sands process-affected water. This includes several compound classes, including aromatic, adamantine, or diamondoid structures, sulphur- and nitrogen-containing compounds, and oxygenated acids.