Benzene levels temporarily spike near Aamjiwnaang First Nation

As petrochemical company Ineos Styrolution removes benzene from a tank close to Aamjiwnaang First Nation, an environmental expert says those who have evacuated from the areaare justified in their concerns about chemical pollution.

Miriam Diamond, an environmental science professor at the University of Toronto, says the area just outside Sarnia, Ont.is already considered a "cancer cluster" due to data collected in recent years.

"I think it's very reasonable the community evacuates," she said.

"We know that higher levels of exposure to benzene has been linked to different types of leukemia in particular."

Of the about 900 people who live on the reserve, approximately 100 people began to evacuate on Tuesday over fears of higher than normal levels of the airborne chemical.

Levels ofbenzene spiked midday Wednesday.

Ineos notified the community of benzene levels above 67.5 microgram per cubic metre that day, and air quality monitors tracked levels as high as 81 micrograms per cubic metre. Levels dipped later Wednesday afternoon.

If, or when, levels reach 90 micrograms per cubic metre, the federal government can begin to levy fines.

The First Nation has set its own benchmark for harmful levels of 27 micrograms per cubic metre, which triggers the closure of some band facilities and offices.

Chief Janelle Nahmabin said the issue is about more than just one particular company, and noted that many in her community have breathing issues including asthma.

In a statement, Ineos said that "despite our best efforts, our modelling suggests that the destocking plan...may result in benzene emissions exceeding the recently lowered regulatory limits."

The First Nation has been under a state of emergency since the spring, when consistent high levels were reported from local monitoring stations.

Calling it a "long-term, festering problem," Diamond says it's important to note benzene levels in the community have been increasing over the past five years or so.

"The risk of contracting cancer increases with the length [of time] you're exposed to a carcinogen."

Ineos issued a statement earlier in the week saying the entire removal of the chemical should be done by Oct. 16 with an increased potential for emissions between Oct. 2 and 6, according to modelling.

"Any elevated emissions are expected to be localized near the site boundary and are not expected to cause adverse effects to the local population," the company said in a statement.

Diamond says while it's difficult to evaluate actual risk, it's important for everyone to take precaution to try and minimize them.

"We can't wait and we don't want to wait for clarity on a very uncertain number of what the actual risk would be."

The federal government announced Wednesdaymodernization and administrative changes to the Canadian Environmental Protection Act. The changes include a proposed "watch list" for substances that have hazardous properties but are not currently defined as toxic, as well as a "plan of priorities" explaining "how the government will address chemical substances in Canada."

Federal Environment MinisterSteven Guilbeault said the announcement was about "putting Canadians first," and the government will "continue to work with [Aamjiwnaang First Nation]hand-in-hand to monitor the situation and to intervene again ifneed be, regarding this company or other companies."

"Canadians want to know that their government is taking action against pollution," he said. "We must ensure the health of all communities."