Inside the shape-shifting rules for pollution in Sarnia’s Chemical Valley

Last spring, Aamjiwnaang First Nation hit a breaking point. For weeks, enormous amounts of benzene had been leaking from a plastics plant across the road from the southwestern Ontario community’s band office. Long-term exposure to low levels of benzene causes cancers like leukemia. If you breathe in a lot of it at once, the carcinogen can also make you feel very sick, very quickly — and people in Aamjiwnaang were breathing in levels of benzene hundreds of times higher than what health-based guidelines recommend.  Sore throats, nausea, dizziness and headaches struck members of the Anishinaabe community, located alongside a cluster of petroleum and petrochemical plants in an area of Sarnia, Ont., known as Chemical Valley. A few wound up in the emergency room due to “noxious exposure,” the local hospital said at the time. The nation sent staff home from the band office and warned families to stay away from a playground. On April 25, 2024, the nation triggered a state of emergency, a watershed moment that made headlines across the country. Daily averages of benzene exposure: Left: 2.3 micrograms per cubic metre is Ontario’s recommended limit for daily benzene exposure. The recommendation was designed to minimize cancer risk, but is not legally binding. Centre: 50 micrograms per cubic metre was the daily reading in Aamjiwnaang First Nation on April 16, 2024, when people in the community reported headaches and nausea. Right: 320 micrograms per cubic metre was the level Ontario told INEOS, in 2019, it would use to assess the risk of acute health problems from the company’s benzene emissions. It’s based on standards from Texas that have been criticized for leaving residents at high risk of cancer. Graphic: Andrew Munroe / The Narwhal The Ontario government imposed new limits on the plastics plant owner, INEOS Styrolution, days later — but years after provincial officials identified the problem. Ontario’s Environment Ministry had known since at least 2019 that INEOS was emitting similar amounts of benzene regularly and failed to stop it, documents obtained by The Narwhal through freedom of information show. The company said it has always remained within its legal limits for emissions. The documents show the province knew the threshold for benzene posed a significant health risk to Aamjiwnaang First Nation long before imposing the new limits. The Ontario government’s delayed action is one example of a pattern laid out in more than 250 pages of records obtained by The Narwhal, all dated from fall 2023 but detailing events that happened years earlier. In 2022 and 2023 alone, the Environment Ministry documented at least six incidents where the company leaked enough benzene to risk acute health problems for people nearby, according to the documents. That included two incidents where levels of the chemical were higher than what triggered the 2024 state of emergency — when the province took stricter steps to curb emissions. Beyond that, the documents show government officials realized INEOS and other facilities were emitting more benzene than the Environment Ministry was originally aware of, in large part due to leaks from storage tanks. Despite this, officials still declined to take steps to limit them. Altogether, it paints a hazy picture of how industry is regulated in Chemical Valley, and just how bad the air really is. It’s an issue Aamjiwnaang First Nation has been raising red flags about for years — and increasingly taking into its own hands, establishing air pollution standards, increasing its oversight of the maze of pipelines that cross the reserve and working with the federal government on a pilot project addressing environmental racism.  “We cannot wait for governments to be the one that acts for us,” Aamjiwnaang Chief Janelle Nahmabin said in an interview. “We need to be there as well.” On June 13, Aamjiwnaang’s band council again recommended certain areas of the community be evacuated due to high benzene levels from the INEOS plant — though the levels were still legal under provincial guidelines. In a letter to several federal and provincial ministers and mayors, the band council wrote the community’s annual powwow was scheduled for the June 21 weekend, coinciding with National Indigenous Peoples Day. The event already saw lower than usual attendance last year “due to fear in the community over benzene exposure and potential health impacts.” Aamjiwnaang First Nation Chief Janelle Nahmabin signed the terms of reference for addressing environmental racism in her community alongside the federal government this year. Aamjiwnaang was the first community to do so under Bill C-226, the National Strategy Respecting Environmental Racism and Environmental Justice Act. Ontario’s Environment Ministry did not answer detailed questions from The Narwhal about the documents and how it regulates air pollution in Chemical Valley. The Narwhal also sent detailed questions to INEOS Styrolution. The company did not answer most of them, but sent a statement saying it prioritizes safety and has “consistently operated within the strict limits” set by the Environment Ministry. “INEOS Styrolution remains steadfast in its commitment to protecting the health and safety of our employees and the community, and we have consistently adhered to [the Ministry of Environment, Conservation and Parks’] emissions requirements,” spokesperson April Ludwikowski wrote. Benzene emissions in Chemical Valley higher than reported estimates  Aamjiwnaang is located on the St. Clair River, just south of Lake Huron. The nation’s name means “at the spawning stream” in Anishinaabemowin. Today, about 900 people live on its reserve, where cul-de-sacs are lined with brick houses and a creek trickles past the nation’s community centre.  Every year, as spring turns to summer, more than 10,000 sturgeon — a species that’s endangered on the Great Lakes — return to the river to spawn, many of them meeting below the Bluewater Bridge, which connects Sarnia to Michigan. When The Narwhal visited in February, a kingfisher dove to scoop fish from the icy waters while an eagle soared overhead.  Still, Chemical Valley is nearly always visible over the tops of trees and fences, its stacks and tanks a reminder of the heavy industry a stone’s throw away. The Sarnia area’s history with petroleum and petrochemicals stretches back to the mid-1800s, when the first oil well in North America was drilled nearby, in a village now named Oil Springs. Refineries soon followed. During the Second World War, Sarnia produced synthetic rubber for the Allied forces. Even more companies followed after the war ended, and Chemical Valley now hosts about 60 refineries and chemical plants.  Aamjiwnaang First Nation’s band office is directly across the road from INEOS Styrolution, which has long been allowed by the province to emit high levels of benzene, resulting in the office being temporarily closed and staff sent home feeling ill. As workers flooded the area in the 1940s, a village called Blue Water sprang up outside the gate of the first plant in Chemical Valley. Governments ended up relocating residents away from it two decades later, concerned about how living there could impact their health. Aamjiwnaang’s baseball diamond is located about 800 metres from the plaque that now commemorates the old village site. The nation is still surrounded by industry. INEOS is among the closest plants to the reserve, directly across the road from Aamjiwnaang’s band office and that same baseball diamond. The plant has been shut down since regulators stepped in last spring, and INEOS has announced plans to decommission it by the end of 2025. But for years it was a “heavy benzene emitter,” according to internal Environment Ministry documents — releasing “significantly more” than other facilities in Chemical Valley. Benzene is a byproduct of petroleum refining that’s also found in crude oil and fuel. It’s one of the foundational ingredients in plastic that, along with other chemicals, can be used to make anything from food containers to car parts. At its Sarnia facility, INEOS Styrolution used benzene to make plastic and rubber. It stored the benzene — which regularly came from refineries in the area — in massive tanks that were known to leak, according to the documents.  Aamjiwnaang residents are exposed to way more of the chemical than people living in big cities and other industrial areas: 30 times more benzene than people living in Toronto and Ottawa, according to the First Nation, and 10 times more than a city in California that has a similar mix of plants.  The flags of Aamjiwnaang First Nation and the Anishinabek fly over the community at the shore of the St. Clair River. “Ontario’s air pollution requirements to limit industrial pollution are lagging requirements in the U.S.,” said a briefing prepared for then-environment minister Andrea Khanjin in late 2023, noting the elevated levels of benzene and other pollutants near Aamjiwnaang. “In many cases, Ontario’s facilities emit far more than comparable U.S. facilities.”  Aside from the long-term cancer risk that comes from breathing in small amounts of benzene, exposure to a lot of it at once can cause headaches, tremors and dizziness.  One set of provincial guidelines that consider cumulative sources of air pollutants, but aren’t legally binding, recommends benzene levels stay below a daily average of 2.3 micrograms per cubic metre. On April 16, 2024, during the event that sickened people in Aamjiwnaang, the daily average was 50 micrograms per cubic metre. On April 25, the hourly reading at a community air monitor reached 191 micrograms per cubic metre. Ontario’s air quality regulation, which considered the long-term cancer risks posed by benzene, mandates average concentrations of the chemical be no higher than 0.45 micrograms per cubic metre annually. But the air quality regulation does not apply to some of the companies operating in Chemical Valley. INEOS Styrolution’s Sarnia plant, along with six other facilities in the area, are exempt from provincial benzene emissions guidelines because it wouldn’t be “technically and economically feasible” to meet them, according to the Ontario government. Instead, the seven facilities follow a set of rules called “technical standards,” which are also common in other types of industrial sites, like pulp and paper mills and asphalt plants. The provincial Liberal government of the day created the standards covering petrochemical plants and petroleum refineries in Sarnia in 2016 after industry there pushed back on the province’s air quality standard for benzene, then a brand-new policy. Just beyond Aamjiwnaang First Nation is the Suncor Sarnia Refinery, top left, which produces gasoline, diesel and jet fuel, among others. Throughout the community, areas are blocked off, right of ways cleared and markers stand up to note the location of pipelines underground. Technical standards don’t put a hard limit on benzene emissions. The ministry instead requires companies to use the best available equipment to lower emissions as much as possible. To get there, the standards have requirements around emissions-reduction technology and air monitoring, among other things, and the Ministry of Environment can order more measures if it believes they’re needed.  The technical standards affecting Chemical Valley were written based on an assessment of benzene sources in Sarnia. They used air monitoring and a review of how much several facilities were emitting at the time, the ministry said in 2016.  Some of the estimates the ministry relied on were provided by industry — and in at least one case, they were wrong, according to a briefing note prepared for Khanjin in late 2023. The memo points to one company as an example: INEOS Styrolution, which it said was emitting maximum concentrations of benzene 15 times higher than what the province was aware of.  The documents do not detail how the error happened, which other companies may have also submitted incorrect estimates or when the Ontario government realized its gauge of benzene emissions was wrong. The Narwhal sent questions about the problem, including direct quotes from the documents, to every company in the Sarnia area that operates under a petrochemical or petroleum industry technical standard, a list that also includes Imperial Oil, NOVA Chemicals, Shell Canada, Suncor Energy and Diamond Petrochemicals. Two responded. INEOS denied giving incorrect information to the ministry: “At no point have we underreported our emissions or misled the regulator,” Ludwikowski said. Imperial said it “complies with air emissions reporting requirements under the applicable regulations” but “wouldn’t be able to speak to documents” that it hasn’t seen. Factories and oil refineries have given Sarnia’s Chemical Valley its name, but long before they arrived here, Aamjiwnaang First Nation has used the area along the St. Clair River, just south of Lake Huron. The nation’s name means “at the spawning stream” in Anishinaabemowin. Ontario’s Environment Ministry did not answer questions about the flawed figures. The documents obtained by The Narwhal show the current Progressive Conservative government has been aware of how much benzene INEOS was actually emitting since at least 2019, when a new air monitor started picking up high levels at times when the wind was blowing from the direction of the plant. Ludwikowski, the INEOS spokesperson, said the company maintains “full transparency” in its emissions reporting. “Property line emissions monitoring at our Sarnia site is conducted by independent third parties, in accordance with [Ministry of Environment, Conservation and Parks] requirements, ensuring there is no internal influence over the results,” Ludwikowski said in a statement. Ludwikowski and INEOS Styrolution did not directly answer follow-up questions. The Ford government was scheduled to review the policy in 2023 but skipped it — despite a warning in the 2023 briefing for Khanjin that said updates are “needed.” The same document also noted companies would likely push back.  “Industry is looking for further simplifications and relaxations,” the memo said. “Will be opposed to more stringent requirements.” The update to the technical standard was one of several air pollution-related moves the government hadn’t followed through on, the memo indicated. Another was a planned update to a policy that, among other things, was aimed at addressing the cumulative effects of benzene emissions from multiple facilities both in the Sarnia area and Hamilton. The previous Liberal government introduced the policy in its last few months of power in spring 2018 and committed to reviewing it by 2020, but the Progressive Conservatives did not follow through.  In April, Aamjiwnaang’s band council temporarily closed access to the community’s cemetery after a benzene spill from the adjacent Suncor refinery. A few days earlier, the company spilled hundreds of litres of crude oil into the river. Ontario allowed INEOS to emit benzene levels higher than what led to Aamjiwnaang’s state of emergency  In spring 2019, after the new air monitor near INEOS Styrolution’s Sarnia facility started to show how high its benzene emissions were, the Environment Ministry issued the first in a series of compliance orders, mandating the company take steps to gradually cut its benzene emissions.  Compliance orders are usually legally binding, and the ministry can use them to compel companies to fix issues and prevent harm to people and the environment. In practice, however, Aamjiwnaang has said the ministry failed to engage with the nation about the orders, which were not enough to protect people from contaminants. “Aamjiwnaang has not been involved in the decision-making” Nahmabin told The Narwhal. “And that’s what we’re looking for, because this is our territory, this is our home.” The goal of the spring 2019 order to INEOS was to eventually get average benzene emissions below 4.5 micrograms per cubic metre annually, and 30 micrograms per cubic metre over a two-week period. The figures were higher than Ontario’s health-based standards, but would reduce the cancer risks to people nearby, according to the government records obtained by The Narwhal.  Annual averages of benzene exposure: Left: 0.45 micrograms per cubic metre is Ontario’s legal annual average for benzene emissions, based on the risk of cancer. Many industrial facilities in Sarnia, Ont., are exempt from this limit and instead follow technical standards that require certain emissions-reduction technologies be used. Right: 4.5 micrograms per cubic metre is the annual average the Ontario government told INEOS in 2019 it should aim to gradually reduce its benzene emissions to. Graphic: Andrew Munroe / The Narwhal But the order didn’t come with a strict limit and a timeline for getting there. It also appeared to clash with a letter the province sent in January of the same year, which included a looser target. They recommended benzene levels remain below an hourly average of up to 580 micrograms per cubic metre — three times more than the levels recorded in Aamjiwnaang as people went to the emergency room in 2024. Those benchmarks were based on standards from Texas, whose benzene limits are the loosest in the United States and have been criticized for putting residents at higher risk of cancer. Aamjiwnaang Chief Nahmabin said the benchmarks were a “slap in the face.”  “Why is that allowed when we’re right across the street?” she said. “That just seems very disheartening for the health of our community and our staff that are right there.” Those January 2019 guidelines also included a limit of 30 micrograms per cubic metre over two weeks, in line with the province’s goal for INEOS. If the company breached it, the Environment Ministry warned it would be in touch to figure out the root cause and, “if necessary, identify corrective actions,” the letter said. The limits in the January 2019 letter were “not regulatory benchmarks,” the ministry wrote, but would instead be used to “assess acute exposures” of benzene. Ludwikowski, the INEOS Styrolution spokesperson, said in her statement that the 580 micrograms per cubic metre was an “established” emissions limit set by the ministry, but did not answer follow up questions about it. Despite the heavy presence and impacts of industry in Sarnia, nature is abundant around Aamjiwnaang First Nation. “To further reduce emissions, INEOS Styrolution has proactively invested $50 million in modernizing the Sarnia plant,” Ludwikowski wrote. “As a result, our emissions have remained well below the [ministry’s] established limits of 580 [micrograms per cubic metre] over an hour. … These plans and timelines were developed collaboratively with the [ministry] and received full regulatory approval.” The Environment Ministry did not answer questions about the benchmarks outlined in the January 2019 letter and how it applied them to INEOS.  Air monitors near INEOS continued to detect spikes of benzene for five years after the ministry sent the company contrasting targets. INEOS complied with the asks in the ministry’s 2019 order, but “elevated benzene emissions from the site” persisted in 2020, according to one internal ministry document. The ministry issued a second order that year asking the company to install more emissions control equipment. Those measures reduced benzene emissions in some areas around the plant, but not all, the ministry found — prompting it to send INEOS a third order in May 2023. Benzene concentrations at one air monitor in particular “have increased every year following the issuance of the orders, indicating that benzene emissions at this location have not been addressed and may instead be worsening,” the 2023 order said. The order also outlined six periods in 2022 and 2023 where air monitors detected “significantly elevated” concentrations of benzene from INEOS. In February 2022, for example, the ministry noted a two-week average of 122 micrograms per cubic metre, four times higher than the ministry’s goal for the facility. That August, the ministry detected an hourly average of 290 micrograms per cubic metre, a concentration of 100 cubic metres more than the peak levels of benzene that sickened people in Aamjiwnaang in spring 2024. An air monitor recorded even higher readings for three consecutive hours in January 2023, with levels in the 300s, the order said. Hourly averages of benzene exposure: Left: 191 micrograms per cubic metre was the hourly reading recorded at an air monitor in Aamjiwnaang First Nation on April 25, 2024, the day the First Nation triggered a state of emergency. Right: 580 micrograms per cubic metre is the hourly average Ontario instructed INEOS to use in 2019 to assess acute health risks. It’s also based on the Texas standards, and is several times higher than the levels that sent people in Aamjiwnaang to the hospital in 2024. Graphic: Andrew Munroe / The Narwhal INEOS told the ministry the benzene emissions were caused by spills, planned maintenance and the “prolonged storage” of waste containing the chemical in one particular area, the document said.  None technically violated the laws governing the company, even though benzene concentrations in Aamjiwnaang had been so high they would bring a “non-negligible risk of cancer for those who may be exposed to such concentrations over the long term,” the order, signed by a ministry officer, said.  “I believe that the [INEOS] site continues to be the primary source of the elevated benzene concentrations measured within the [Aamjiwnaang] community and that additional measures are required.” Those measures included more technological upgrades and requirements to notify the ministry about various aspects of the operation of INEOS Styrolution’s plant. Like the previous orders, they did not include firm emissions targets for the company.  INEOS pushed back, according to a document prepared by ministry officials that outlined the context for air quality measures in Sarnia: “INEOS [is] concerned that orders require them to do too much, too soon. They believed that since they were complying with the [standard], they shouldn’t have to do more.” Ludwikowski didn’t directly answer questions about the company’s conversations with the Ontario government.  A storage tank at Shell’s refinery in Sarnia features ‘Ojibwe Spirit,’ a mural by Aamjiwnaang First Nation artist John Williams, unveiled in 2022 to honour the land and people of Aamjiwnaang. By the end of 2023, Aamjiwnaang had maintained the orders were “inadequate and slow,” according to the late 2023 briefing. And in the meantime, a long-anticipated health study funded by the Ontario government reiterated what people from the First Nation have been saying for a long time: air pollution from Chemical Valley was putting people’s health at risk in Aamjiwnaang. First Nations were “frustrated,” the briefing noted, because “proven technologies exist that can better manage and control” emissions of benzene and other pollutants. “They also believe that [the ministry] provides priority access to industry and that [the ministry] continues to ignore the First Nations’ input,” the briefing said. In one meeting between ministry staff and the nation, Aamjiwnaang representatives warned the Ontario government it would “take actions into its own hands” if the ministry didn’t act quickly to limit air pollution.  The Environment Ministry did not answer questions about the meeting, and it’s not clear what steps it might have taken afterwards. In a notice sent to INEOS in 2024, which the province publicly posted online, the ministry said it had developed new interim guidelines in December 2023 — the month after the health study was released — about how staff should interpret the risks posed by benzene exposure. Those internal guidelines indicated exposures of 90 micrograms per cubic metre over an hour, or 30 micrograms per cubic metre over 24 hours, would increase acute health risks. Those thresholds are dramatically lower than the 580 micrograms per hour the ministry recommended in its 2019 letter to INEOS, but still far higher than benzene standards that take long-term cancer risk into consideration. A few months later, in April 2024, as benzene levels spiked in Aamjiwnaang and sent people to the emergency room, the ministry issued INEOS a fourth order. It required INEOS to notify the public if readings of benzene spiked, develop another plan to “address benzene from wastewater” and investigate where the carcinogen might be coming from. High levels of benzene were reported again a week later, prompting Aamjiwnaang to issue its state of emergency. The following month, Ontario barred INEOS from storing benzene at its Sarnia site and suspended its approval to operate until the company made major repairs. The federal government stepped in at this point, issuing a temporary order to petrochemical companies in the area to cut benzene emissions. (The federal government has some jurisdiction to set nationwide air quality rules, like laws limiting emissions from new cars, but usually leaves local air quality rules to provinces and territories.) Ontario followed suit, imposing benzene limits of its own on INEOS that came into effect that June. The limits, which remain in place, include a cap of 90 micrograms per cubic metre over an hour. It limited annual average emissions to 4.5 micrograms per cubic metre — 10 times higher than the province’s usual air quality standards.  Ludwikowski said those limits were “stringent” and “imposed without prior notice, consultation or a sufficient time for implementation.” INEOS temporarily shut down the plant following the ministry’s 2024 order, and soon announced it would close the plant entirely due to the “economics of the facility within a wider industry context.” It said the situation was unrelated to the benzene spikes.  “We cannot wait for governments to be the one that acts for us,” Chief Nahmabin said. She continues the fight against industrial pollution in her community, and for an end to environmental racism here. The process of shuttering the facility is scheduled to be finished by the end of 2025. Aamjiwnaang’s state of emergency is still in place, and won’t be lifted as long as benzene continues to be stored at the site, Nahmabin said. Benzene levels on Aamjiwnaang have mostly stayed lower since spring 2024, but the risk isn’t gone. As well as the most recent partial evacuation in mid-June, days before Nahmabin spoke to The Narwhal in late May, high benzene readings forced the community to close buildings and warn people away from the baseball diamond. In April, Aamjiwnaang temporarily closed access to the community’s cemetery after a benzene spill from the adjacent Suncor refinery — days after the company also spilled hundreds of litres of crude oil into the river. Suncor did not answer questions from The Narwhal about either incident. In January, the Chemistry Industry Association of Canada told the Sarnia Observer that without INEOS accepting benzene produced as a by-product at other sites in Chemical Valley, companies had resorted to moving it out of the region by ship, rail and truck.  Aamjiwnaang has asked the province for copies of any approvals it has granted to companies to store benzene in the area, Nahmabin said. “The problem is not going away, we just want to make sure that it’s being handled safely.” Nahmabin is hopeful governments now understand they have to work with Aamjiwnaang to fix their oversight of Chemical Valley. “It’s a big can of worms, and it’s peeling back decades of environmental racism,” she said.  “We see the gaps, and this is where we feel like we can step in to effectively regulate Chemical Valley, because we’re here. This is our homeland. This is our Traditional Territory.” Recent Posts Make Canada Build Again? 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