Health officials say they are most concerned about arsenic in the Toquaht Bay marina and campground, which can be poisonous in small doses.
Dr. Paul Hasselback, the medical health officer for central Vancouver Island, said any exposure would come from drinking or eating the arsenic — though that's unlikely to happen.
"The water isn't drinkable — it's salt," he said in an interview. "Most people don't consume soil."
While he conceded those who used the recreational area would certainly be concerned, he said the health authority isn't aware of anyone getting sick.
Symptoms of acute arsenic poisoning including stomach pain, vomiting, diarrhea and impaired nerve function, which could result in a pins-and-needles like sensation in hands and feet.
The site was developed into a recreational area after the closure of the Brynnor Mine in the late 1960s.
The land was transferred to the Toquaht First Nation in a treaty that came into effect in 2011.
The province agreed to undertake environmental inspections and remediate any contaminants as part of the treaty, and those tests revealed the toxins.
While the testing only began a short time ago, Hasselback agreed the arsenic could have been a problem for a much longer period.
"The findings are certainly not something that was anticipated."
The government said the area is expected to be closed to visitors for at least eight weeks, at which point officials expect to know what's needed for remediation of the site.
Hasselback said those findings will determine when the area might be re-opened.
In his several-decade career, the doctor said he's never come across a case of arsenic illness.
"We do try very hard to minimize anyone's exposure."
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