A corrosive gas that is fatal to humans in high concentrations should not be a toxic substance under Canadian environmental law, say federal researchers in a new proposal.

Health Canada and Environment and Climate Change Canada staff came to this conclusion in a draft assessment of hydrogen sulphide published in September. Their assessment found that hydrogen sulphide, also known as H2S or sour gas, does not enter the environment in quantities, concentrations or conditions “that constitute or may constitute a danger in Canada to human life or health.”

The conclusion is at odds with the substance’s track record — H2S has already killed at least one oilpatch worker in Canada, while sickening dozens of others and killing livestock.

Sour gas, known for its rotten egg smell, is commonly found in hot springs, volcanic gases and biological waste, but can also leak from the wellheads, tanks, pipes and flare stacks of the oilfields. That’s where most high-concentration encounters tend to occur.

An October investigation by National Observer, the Toronto Star and Global News revealed a series of oil and gas industry run-ins with H2S that resulted in injury or death.

According to the federal proposal such industrial releases aren’t representative of ambient conditions in Canada, and therefore “not considered relevant” under the Canadian Environmental Protection Act (CEPA). If the government approves the proposal neither Health Canada nor Environment Canada will crack down on industrial releases of the dangerous substance.

A Health Canada spokeswoman wrote in an email that “occupational exposure falls under provincial jurisdiction,” and is not included in general population risk assessments under CEPA.

A coalition of scientists, lawyers, doctors and environmental advocates is concerned with that interpretation. The government “has failed to adopt a science-based, precautionary approach” to assessing H2S health risks in Canada, they wrote in a letter to Environment Canada last month.

The plan doesn’t sit well with the victims of H2S exposure either — Jeff Crawford, a former oilfield worker who lives with permanent disability as a result of the gas, called the non-toxic assessment “incredible.” Crawford was hit in the face by a mixture containing H2S on the job in 2014, and today, suffers from PTSD, anxiety, dizziness and difficulty with eating, breathing, speaking, smelling and sleeping.

“It’s like saying cancer is not a disease,” he said in an interview. “I’d like them to sit in front of me and tell me they’re doing that. I’d tell them what I think about it.”

Former Saskatchewan oilfield worker Jeff Crawford nearly died in a February 2014 accident. Three years later, his body struggles to complete its most basic tasks: chew food, swallow, taste, smell, speak properly, breathe clearly and sleep soundly.

Read more:

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Hydrogen sulphide, Health Canada noted, is already subject to a number of provincial, territorial and federal regulations on hazardous materials, environmental and air quality, and occupational health and safety. Additional monitoring, inspection, data collection and measurement takes place within the oilpatch to protect workers and the public from rogue H2S emissions that may find their way into unwary communities.

Like reading that water ‘isn’t wet’

“That H2S is toxic should be beyond debate,” the coalition letter reads. “It is plain that releases of H2S may occur as a result of oil and gas operations … It is equally plain that a release may constitute a danger in Canada to human life or health.”

The federal proposal — while not yet finalized — also dismisses H2S’s rotten smell as a “nuisance,” without “scientific or legal justification,” it argues, and did not base its decision on the very lowest H2S exposures that are known to cause adverse health effects to humans.

Its focus on the general population, the groups say, also fails to consider vulnerable communities living near industrial operations, whose quality of life may be compromised by constant odours or even endangered in the event of a leak or spill.

“It’s kind of like reading that water isn’t wet,” said Elaine MacDonald, an environmental engineer at Ecojustice and director of its healthy communities program.

“That’s why we decided to write the letter. We couldn’t let it go … This is probably close to a 10 out of 10 in terms of ignoring the evidence.”

Science Minister Kirsty Duncan declined to comment on whether the federal proposal was evidence and science-based, and requests for comment from Environment Canada on human health and sour gas were referred to the health department.

Health Minister Ginette Petitpas Taylor did not respond directly to written questions, but issued the following statement via email:

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“Canada’s Chemicals Management Plan is a world-leading program that is contributing towards the global goal of sound management of chemicals. In Canada, hydrogen sulphide is subject to a number of risk management measures, which are included in provincial and territorial regulations and guidelines for air quality, including the control of releases from industry.”

Federal plan acknowledges data shortfalls

According to Health Canada, it’s not “unusual” for an assessment under CEPA to rule that a substance with highly hazardous properties is non-toxic. In May 2016, for example, the federal government determined that a group of azo dyes — known carcinogens — were non-toxic, since their exposure to people is very low, or non-existent.

But there are data gaps in their assessment of human health and H2S, wrote the researchers who submitted the draft assessment for sour gas. Long-term chronic experimental studies on the gas’s impact on human health are either limited or non-existent, the proposal notes, as is data on industrial releases in certain sectors (metal and metal refining, for example) located close to human populations. Researchers did however, access and consider decades of hourly H2S measurements taken in the air near pulp and paper mills, oil and gas fields, livestock farms and more.

The federal government said the assessment also considered exposure to people who live near industrial facilities, but that “focus on general population exposure,” has been its practice since the inception of the Chemicals Management Program — a sweeping evaluation of more than 4,000 chemical substances under CEPA with a deadline of March 2021.

That evaluation takes place as the federal government deliberates changes to the aging legislation, which has not been updated since 1999. A June 2017 report by the Standing Committee on Environment and Sustainable Development identified several key “weaknesses” in CEPA’s regulatory framework, and made a number of recommendations that could impact what kind information it considers in assessments. Several of them include special consideration for “vulnerable communities,” like those living in proximity to industry operations.

The federal government will respond to those recommendations in June 2018, but to rule on H2S while the entire act is called into question is “definitely irresponsible,” said former corporate lawyer and environmental law expert Jason MacLean.

“It looks like a decision that’s irrational and negligent on its face and it looks even worse I think to be doing this while (CEPA) is under consideration,” the assistant law professor at University of Saskatchewan, told the investigation. “It looks hasty, it looks rushed, and that’s not in the public interest.”

If the federal plan is approved however, and someone gets sick from ambient exposure to H2S, MacLean said it would be “an uphill battle” to try and sue the federal government for its ruling that the substance isn’t toxic under CEPA. One would have to prove that Ottawa was negligent and “flying in the face of independent scientific findings” in its chemicals assessment, he explained, but “any amount of legitimate scientific doubt” to those claims could probably take the case apart in the courts.

Three years after an accident at a Saskatchewan oilfield, former oilfield worker Jeff Crawford still suffers severe health problems. Crawford, who suffered chemical burns in the ordeal, only eat food in a mashed-up liquid diet. He has lost his sense of taste or smell, and he must sleep upright, or else he ends up choking.

Independent scientist backs assessment

Geoff Granville, a Calgary-based scientist with expertise on managing the risks of toxic substances, said in an interview that he agrees with the government’s draft assessment of H2S. People in a nonoccupational setting are not usually at risk, he explained, and if an incident does occur outside of the workplace, it may be accidental with unknown or extraordinary causes.

That’s tough for the federal government to regulate pre-emptively, said Granville, and not within the scope of CEPA: “It’s not (about) risk based on an accident situation, otherwise cars are toxic. That makes no sense. It’s not accident driven, it’s got to be by the way the world operates.”

Encounters based on industrial and workplace exposure, he added, are another matter entirely. Bad industry practice is unacceptable, said Granville, but since most industry regulation falls within the jurisdiction of provincial regulators and governments, it may be more practical for Ottawa to find other methods of encouraging adherence to H2S regulations than cracking down with the full force of CEPA.

The question then becomes, said Granville, what more can the federal government do to protect public safety?

He advocated for co-operation between jurisdictions to help address people’s “very natural” fear of H2S, like strengthening whistleblower programs or starting a conversation about how to handle to low, foul-smelling but ultimately not dangerous levels of H2S. In the context of CEPA, he said the word “toxic” takes on a legal meaning of its own, and much of the outrage with the federal plan has to do with semantics.

“So how do the feds shame a provincial environmental ministry to step up and really regulate and do its job better?” he asked. “Whether you call it toxic or not, I actually think the feds could say, ‘We’re concerned about low levels of exposure to the public, which does happen, and therefore, we’re willing to prepare something to work with other jurisdictions and do x, y, z.’”

The government’s assessment isn’t final, and while the public commentary period has officially closed, Health Canada is encouraging stakeholders to submit “any additional information that should be taken into consideration.” In conjunction with Environment Canada, the department will publish a summary of public commentary on its proposal, its responses to those comments, and its final assessment of H2S in 2018.