High levels of tritium contamination found in samples from Pembroke
MARTIN MITTELSTAEDT, ENVIRONMENT REPORTER, The Globe and Mail
November 12, 1999
Radioactive matter shows up in rink ice, cucumbers, and woman’s urine
High levels of radioactive tritium are being found throughout Pembroke, the site of a plant that recycles the waste material to make glow-in-the-dark signs. Tritium has been discovered in the ice of a local hockey rink, in cucumbers and in the urine of one of the residents of the Ottawa River Valley city.
Although the tritium levels that were found were up to 1,500 times higher than the concentrations in rainwater, the Atomic Energy Control Board says they pose negligible risk of causing cancer.
Despite the assurances of the country’s nuclear watchdog agency, Kelly O’Grady, whose garden contained the radioactive cucumber, says she no longer wants to eat the food from her garden or feed it to her children.
“I don’t think it’s safe to be eating vegetables from our garden any more. We feel that our rights have been violated, that we should be able to plant a tritium-free garden,” Ms. O’Grady said.
The urine and cucumber samples were tested by Pembroke residents worried about emissions from the sign factory, owned by SRB Technologies (Canada) Inc., but it was the AECB that tested tritium levels in the ice rink, swimming pool water, and soil and vegetation throughout the community, including the local tourist bureau.
Tritium is a radioactive form of hydrogen and is an unwanted waste product of Canadian nuclear reactors. It has commercial applications for use in signs that glow in the dark without electricity, such as exit signs, but it is also a key component of thermonuclear weapons.
Tritium is considered by scientists to be the least dangerous reactor waste, but there is controversy over what constitutes safe levels, with some experts advising tighter standards, particularly for pregnant women.
SRB Technologies has said in a written statement that it operates “well within” the guidelines and regulations set up by the AECB and has processes in place to ensure that staff and the public are not at risk.
The woman who had her urine analyzed asked not to be identified.
In response to concerns about tritium releases, which made headlines earlier this year when radioactive rhubarb was found in the city, the control board conducted extensive sampling of soil and vegetation in Pembroke last month and in early November. Results of the testing were presented to residents and politicians on Monday evening.
The testing by both the board and local residents indicates tritium well above normal background levels in many parts of Pembroke, with the highest readings close to the factory. The ice, for instance, was tested at an arena a few hundred metres from the sign plant.
Patsy Thompson, head of the AECB’s radiological-protection section, said the readings around the sign plant are in line with the radioactivity levels the board would expect for the area, based on the amount of tritium the facility emits during normal operations.
Many residents want the plant to eliminate these discharges, but Ms. Thompson said the board doesn’t try to force nuclear operators to eliminate all radioactive emissions.
“The AECB does not regulate facilities such as SRB and others on the basis of zero discharge,” she said, but added that it tries to ensure that fugitive radioactive emissions are kept at low enough levels to ensure the number of cancer cases stays within the normal range.
She said the radioactivity that Pembroke residents receive from the plant shouldn’t be a cancer worry because the amounts are at low levels.
TRITIUM LEVELS IN SOUTHERN ONTARIO
While the current Ontario safety guideline for drinking water
stands at 7,000 becquerels per liter, a provincial advisory group suggested levels should be no higher than 100 becquerels per litre. A becquerel is a unit of radioactivity; |
SOURCE OF CONTAMINATION | BECQUERELS PER LITRE |
Pembroke urine sample | 590 |
Ice from Pembroke arena | 3,000 |
Pembroke cucumber | 580 |
Pembroke rhubarb | 2,000 |
Pembroke resident’s
swimming pool |
220 |
Average in plants around
Pickering nuclear station |
104 |
Average in plants around
Bruce nuclear station |
48 |
Average in plants around
Darlington nuclear station |
23 |
Ottawa rainwater | 2 |
Source: Atomic Energy Control Board