Canada Gazette, Part I, Volume 158, Number 5: 

May 27, 2024



Order Approving the Interim Order Respecting Releases of Benzene from Petrochemical Facilities in Sarnia, Ontario

P.C. 2024-569 May 24, 2024

Whereas the Minister of the Environment, under subsection 94(1)footnote a of the Canadian Environmental Protection Act, 1999footnote b, made the Interim Order Respecting Releases of Benzene from Petrochemical Facilities in Sarnia, Ontario on May 16, 2024;

Whereas the Minister of the Environment has, within 24 hours after making that Interim Order, offered to consult with all affected governments to determine whether they are prepared to take sufficient action to deal with the significant danger to the environment or to human life or health that the Interim Order is intended to address;

And whereas the Minister of the Environment has consulted with other ministers of the Crown in right of Canada to determine whether any action can be taken under any other Act of Parliament to deal with the significant danger;

Therefore, Her Excellency the Governor General in Council, on the recommendation of the Minister of the Environment, under subsection 94(4) of the Canadian Environmental Protection Act, 1999 footnote b, approves the Interim Order Respecting Releases of Benzene from Petrochemical Facilities in Sarnia, Ontario made by the Minister of the Environment on May 16, 2024.


(This note is not part of the Order.)


This Order, made pursuant to subsection 94(3) of the Canadian Environmental Protection Act, 1999 (CEPA), approves the Interim Order Respecting Releases of Benzene from Petrochemical Facilities in Sarnia, Ontario (the Interim Order) made by the Minister of the Environment on May 16, 2024, extending its application for a period of up to two years from the date the Interim Order was made. The Interim Order, made pursuant to subsection 94(1) of CEPA, addresses a significant danger to human health posed by high benzene levels in Aamjiwnaang First Nation in Sarnia, Ontario, requiring immediate action.


The objective of this Order is to approve the Interim Order, causing it to have effect for a period of up to two years. The Interim Order addresses an urgent and significant danger to human health posed by benzene emissions from petrochemical facilities in Sarnia by requiring these facilities to address emissions from all benzene storage tanks, including fully closing all vents and destroying toxic gases on high-risk sources. The Interim Order is needed to protect the health of the residents of Aamjiwnaang First Nation community located in Sarnia, Ontario that have reported both acute and chronic health impacts from benzene exposure.


Benzene and health risks

Volatile Organic Compounds (VOCs) are gases that are emitted into the air from products or processes which can then impact indoor and outdoor air quality. Benzene is a VOC that is included in the List of Toxic Substances under Schedule 1 to CEPA. Benzene is a known human carcinogen (able to cause cancer). Long-term lifetime exposure to benzene can affect the blood and is associated with an increased risk of developing cancer (for example leukemia) and other adverse health effects including blood diseases and reduced immune functions. Short-term (acute) exposure to benzene in the air may lead to changes in blood cell counts and effects on the immune system. At extremely high levels, benzene can cause irritation to the eyes and respiratory tract and can affect the central nervous system.footnote 1

Inhalation exposure to benzene is of particular concern for populations located in areas where emissions from storage and loading operations contribute to concentrations of benzene in the air.

The CEPA assessment of benzene published in 1993 by the Minister of the Environment and the Minister of Health indicated that the examination of options to reduce exposure should be a high priority and that such exposure should be reduced wherever possible.footnote 2 The National Pollutant Release Inventory reports that Canadian refineries, upgraders, terminals and petrochemical facilities release benzene into the surrounding environment.footnote 3 It is expected that releases of carcinogenic substances from these facilities could contribute to cancer risks for Canadians in the vicinity of those facilities.

The Government of Canada’s Screening Assessment - Petroleum Sector Stream Approach: Natural Gas Condensates footnote 4 concludes that inhalation exposures to evaporative emissions of natural gas condensates from rail and truck loading sites and natural gas condensate storage facilities may constitute a danger to human life or health. This danger is linked to benzene exposure, a high hazard component of natural gas condensates.

Storage and unloading at gasoline stations can pose similar emission exposure risks to local populations, and a recent report from Health Canada concluded that “inhalation exposures to benzene attributable to gasoline station emissions may pose unacceptable risks to human health for the general population living in the vicinity”. Short-term exposure to elevated benzene levels near gasoline stations may also pose a risk to pregnant people and their developing fetuses.footnote 5

The results of the Screening Assessment and Health Canada report are relevant to this situation, even though the emission sources are different, since they both have conclusions regarding the impacts of benzene exposure to local populations. Also relevant is Health Canada’s proposed Residential Indoor Air Quality Guideline for Benzene, which includes a recent comprehensive science review of benzene health effects.

There is no safe level associated with long-term exposure to benzene, and the risks to health increase as benzene concentration increases. However, Health Canada considers 0.6 micrograms per cubic metre (μg/m3) as the benzene concentration associated with an acceptable level of risk for long-term exposure. This value is based on a cancer risk of 1 in 100,000, meaning that such a level could lead to one additional cancer case per 100,000 people over a lifetime. This is the proposed Health Canada Residential Indoor Air Quality Guideline for Benzene and can also apply in the context of outdoor air exposure.

While Health Canada does not have a short-term exposure health benchmark for benzene currently published, Health Canada recommends that short-term exposure to benzene do not exceed 30 µg/m3 (measured on a 24-hour basis). This value was developed by the United States Agency for Toxic Substances and Disease Registry and is based on an extensive evaluation of toxicological information.

Air Quality and Health Risk in Aamjiwnaang First Nation in Sarnia, Ontario

Aamjiwnaang First Nation in Sarnia, Ontario is surrounded by petroleum and petrochemical facilities, and repeatedly faces incidences of elevated levels of air pollutants, including benzene. The main source of the elevated benzene levels affecting Aamjiwnaang First Nation are emissions from storage tanks containing benzene.

There are multiple air quality monitoring stations within Aamjiwnaang’s lands and in Sarnia, including two long-term monitoring sites operated by the Department of the Environment’s National Air Pollution Surveillance (NAPS) program, three long-term monitoring sites and two recent pop-up measurement sites operated by Ontario’s Ministry of the Environment, Conservation and Parks (MECP). Health Canada and the Department of the Environment (the Department) officials have conducted a rapid assessment of benzene exposure levels and health risks impacting Aamjiwnaang First Nation.

Recent information indicates that benzene emissions from nearby petrochemical facilities have increased and are resulting in benzene levels that pose a significant danger to the health of nearby residents of Aamjiwnaang First Nation. The Ada Rogers station, operated by the Ontario government proximate to Aamjiwnaang First Nation community spaces, has recorded annual average concentrations of between 3.14 – 6.68 μg/m3 over the past 5 years. The average benzene concentration since March 2024 has increased to 10.7 μg/m3 (in comparison to the Health Canada benchmark of 0.6 μg/m3 for long-term exposure to benzene). Presented in terms of the risk to developing benzene-related cancer, the cancer risk was approximately 1 in 20,000 (2022), 1 in 10,000 (2023) and recently increased to 1 in 5,000 (2024; based on March 20-April 26, 2024), compared to an acceptable 1 in 100,000footnote 6. These risk estimates are based on being exposed to benzene over the course of a lifetime at these levels. In addition, benzene levels impacting Aamjiwnaang First Nation are higher than those observed elsewhere in Canada. According to data from the NAPS program in 2023, the average national benzene concentration across Canada was 0.52 μg/m3, while the NAPS program station in Aamjiwnaang First Nation had a 2023 annual average concentration of 0.74 μg/m3 (~ 2.5 km from the closest petrochemical facility).

In addition, short-duration episodes of elevated benzene levels have recently increased. From March 20-April 26, 2024, the measurements at the Ada Rogers monitoring site showed 3 out of 38 days exceeding Health Canada’s recommended benchmark of 30 µg/m3 (over 24h-hours, and representative of short-term exposure health risks). By comparison, there were 9 such exceedances overall for the 3 previous years (2021-23). These short-term elevated levels of benzene increase the risk of non-cancer health effects from short-term exposure to benzene as well as contribute to elevated long-term benzene exposure cancer risks.

Since March 2024, Aamjiwnaang First Nation community members have self-reported impacts to their health which they attribute to repeated short-term elevated benzene incidences, further demonstrating the effects of emissions on the health of Aamjiwnaang First Nation.

On April 16, 2024, Aamjiwnaang First Nation closed its community services (e.g. Band Office, playground, sport fields, daycare, and resource centre) and on April 25, 2024, a State of Emergency was declared in Aamjiwnaang First Nation due to high benzene levels. Community services remained closed, and community members have been directed by their leadership to stay at home with their windows closed due to the high levels of benzene in the air, although they are still concerned about indoor air quality within the community. Community services have re-opened, but with notification to the community that they will be closed again if benzene levels at the monitors co-located with Aamjiwnaang buildings exceed 27 μg/m3 (over one hour). These closures continue to happen periodically.

Regulating Volatile Organic Compounds

Federally, the Reduction in the Release of Volatile Organic Compounds Regulations (Petroleum Sector) regulate some sources of benzene emissions located in certain petrochemical facilities that are integrated with refineries. However, they do not apply to standalone petrochemical facilities. On February 24, 2024, the proposed Reduction in the Release of Volatile Organic Compounds (Storage and Loading of Volatile Petroleum Liquids) Regulations (the proposed Regulations) were published in the Canada Gazette, Part I. Among other things, once they are finalized, they would set requirements on tanks and loading equipment, and would apply to standalone petrochemical facilities. These proposed Regulations are expected to be finalized by late 2024 or early 2025 and would require storage tanks with high benzene content to install vapour control equipment within one year. The Department is exploring ways to advance the timelines for the coming into force of these provisions.

In Ontario, benzene is currently regulated provincially under the Environmental Protection Act (EPA). Regulations under this Act prescribe benzene air standards for half hour, 24 hour and annual averaging periods. While the Ontario regulations include a stringent air quality standard, they allow companies to comply in different ways, including by registering for the Petrochemical Industry Standard (PCIS). This alternative compliance mechanism allows some facilities to continue operating even if they do not meet the prescribed air standards in the Ontario regulations.


Gender-Based Analysis+ Considerations

Aamjiwnaang First Nation community has communicated the disproportionate impacts of benzene pollution on their community due to their proximity to industrial sites, and the limited resources available to address pollution concerns due to the ongoing legacy of colonialism and the chronic underfunding of programs and services in Indigenous communities.

Some individuals within Aamjiwnaang First Nation community, or others living or working near facilities with elevated benzene emissions, may be more susceptible to negative health impacts from exposure to benzene. Women are more susceptible to health effects related to benzene exposure than men in the same setting due to metabolic differences. Children are also more susceptible due to physiological and metabolic differences compared to adults. Exposure to benzene during pregnancy has been linked with negative effects, including preterm birth and low birthweight. In addition, studies have linked exposure to benzene during pregnancy or early childhood with an increased risk of childhood leukemia. Further, certain segments of the population may have genetic differences that affect benzene metabolism, increasing susceptibility to adverse health effects. Therefore, reduced emissions of benzene may be expected to have differential positive impacts on these segments of the population, including women, people who are pregnant and their developing fetuses, infants and children.

The First Nation’s local public buildings (e.g., community services) that have closed as a result of the benzene levels disproportionately impact a wide range of community members. The public spaces that have been closed include offices, a playground, recreational spaces, a daycare, and designated outdoor areas. These spaces are disproportionately accessed by women, children/youth, Elders/elderly, people who work/live near the source of pollution, and people who work outdoors. For example, women are often still responsible for caretaking (of children, youth, and the elderly) and the closing of daycares and recreational spaces means that women will likely have to take time off work to care for children and the elderly. Additionally, women often make up most administrative professionals in offices, and the closing of the band office will disproportionately impact women who work there.

The United Nations Declaration on the Rights of Indigenous Peoples Act (UNDA)

Section 5 of UNDA provides that the Government of Canada must, in consultation and cooperation with Indigenous peoples, take all measures necessary to ensure that federal laws are consistent with the United Nations Declaration on the Rights of Indigenous Peoples (UN Declaration) (PDF). This Order contributes to the implementation of the UN declaration in federal law through the promotion of a healthy environment and the protection of human health in Aamjiwnaang First Nation community. By engaging directly with Aamjiwnaang prior to final decisions being taken for the current approach, the proposed Order also supports Aamjiwnaang’s rights to participate in decision-making that is intended to directly impact their community. This would also provide consistency with provisions of the UNDA Action Plan, such as shared priority 66 reflecting Indigenous participation in decision-making. Representatives of Aamjiwnaang First Nation did not identify any ways that this Order could be inconsistent with the UN Declaration.

Interim Order Provisions and Considerations

Under the Canadian Environmental Protection Act, 1999, the Minister has the authority to put in place an interim order if the Minister of the Environment and the Minister of Health believe that a substance listed on the List of Toxic Substances under Schedule 1 to that Act is not adequately regulated, and that immediate action is required to deal with a significant danger to the environment or to human life or health. An interim order made by the Minister ceases to have effect unless it is approved by the Governor-In-Council within 14 days.

Should the Governor-In-Council approve the Interim Order, as per subsection 94(7) of CEPA the Interim Order ceases to have effect on the earliest of: (a) the day it is repealed; (b) the day a regulation replacing it is made; or (c) two years after the order is made.

The Interim Order applies to petrochemical facilities in Sarnia, Ontario, where fenceline monitoring has historically measured benzene levels above 29 μg/m3 over a two-week sampling period. While fenceline monitoring is generally used to measure benzene levels at a facility as opposed to community exposure, in cases where communities are in very close proximity to a facility it can be appropriate to inform potential health risks. In accordance with EPA guidelines, the US Agency for Toxic Substances and Disease Registry has established 29 μg/m3 as an acute inhalation minimal risk level for benzene. It represents an estimate of the amount of benzene a person can breathe each day for up to two weeks without an appreciable risk of adverse noncancer health effectsfootnote 7. The Interim Order requires these facilities to address emissions from all benzene storage tanks, including fully closing all vents and destroying toxic gases on high-risk sources.

Other technical requirements include putting in place a plan to minimize emissions before emptying and cleaning benzene storage tanks, and specific inspection, maintenance and repair requirements to ensure good performance of vapour control systems. Timelines are intended to be short in response to the urgent nature of the situation, while being technically feasible. For example, a vapour control system would need to be installed on the benzene tank of highest concern within 21 days, with other tanks being addressed in the weeks to follow. The Interim Order does allow for extensions to the prescribed timelines in the event of health and safety concerns, however all work must be completed within 90 days. Similarly to the proposed VOC Phase 2 Regulations, the Interim Order would also require vapour control systems for loading operations.

The requirements in the Interim Order were developed based on those in the proposed Reduction in the Release of Volatile Organic Compounds (Storage and Loading of Volatile Petroleum Liquids) Regulations. In other words, the technical requirements imposed by the Interim Order are designed to have a similar effect to those in the proposed Regulations, but take effect much earlier to address the need for immediate action. These timelines are in contrast to the timelines in the proposed Regulations of one year to install vapour control on benzene tanks.

It is expected that the costs to comply with the Interim Order would be the same as those that would be incurred to comply with the final Regulations. These were described in the cost-benefit analysis of the proposed Regulations.footnote 8 Since the Interim Order is accelerating the timeline associated with those requirements, there may be additional cost to installing vapour control measures on an expedited basis.

Aamjiwnaang First Nation will directly benefit from the Interim Order. This immediate action is expected to lower ambient levels of carcinogenic benzene in and around their community.

Supply-chain, Competitiveness and Timing Considerations

The requirements of the Interim Order are not expected to require long term shut downs of facilities. However, should this occur, it could have impacts for the management of benzene in the Sarnia region.

Based on conversations with facilities and associations, there are likely solutions for benzene logistics such as cutting down benzene production at facilities at which it is a by-product by adjusting the production process, storing benzene onsite for a period of time, or transporting it offsite to other potential customers. There may be some impacts on revenues for other facilities in making these process adjustments. The Interim Order is not expected to cause any long-term implications on supply chains.


The Interim Order would be made under CEPA, so enforcement officers would, when verifying compliance with the Order, apply the Compliance and Enforcement Policy for CEPA.


On April 24, 2024, Aamjiwnaang First Nation sent a letter of support for the proposed Reduction in the Release of Volatile Organic Compounds (Storage and Loading of Volatile Petroleum Liquids) Regulations, and requested that their implementation be advanced as quickly as possible in order to reduce benzene emissions in their community to protect human health.

On May 13, 2024, the Minister of the Environment, in accordance with subsection 94(4)(b) of CEPA, consulted with other federal ministers to determine whether any action can be taken under any other Act of Parliament to deal with the significant danger. No other Acts of Parliament were identified by other Ministers.

On May 14, 2024, officials from the Department met with staff from Aamjiwnaang’s Environment Department and Aamjiwnaang’s leadership to discuss the federal approach, understand and evaluate any concerns or questions, and to confirm the community’s support.

On May 17, 2024, within 24 hours of making the Interim Order Respecting Releases of Benzene from Petrochemical Facilities in Sarnia, Ontario, the Minister of Environment offered to consult with the Province of Ontario as required under subsection 94(4)(a) of CEPA.

Given that the technical requirements in the Interim Order were developed based on those in the proposed Reduction in the Release of Volatile Organic Compounds (Storage and Loading of Volatile Petroleum Liquids) Regulations, it is important to note that extensive consultations were undertaken prior to their publication in the Canada Gazette, Part I. The comment period closed on April 24, 2024, and the Department is currently reviewing all comments and assessing their impact on a national scale. The Department noted that concerns were raised by industry about implementation and repair timelines, however these concerns focused on logistical and technical challenges related to continued plant operation while emissions abatement measures are undertaken (e.g. sequentially removing tanks from service).


Magda Little
Oil, Gas and Alternative Energy Division
Environment and Climate Change Canada