Watershed groups start using rapid test kits to monitor cyanobacteria
Kits can get results about a specific area of water in about 40 minutes
New water-testing kits will make information about cyanobacteria toxins, also known as toxic blue-green algae, more readily available to members of the public
Watershed groups are using the kits to monitor for potentially toxic cyanobacteria.
"They're a bit of a game changer because traditionally we would have had to send water-quality tests away to a lab. It was very expensive," said Lauren Murdock, conservation co-ordinator with the Nashwaak Watershed Association.
"These test kits we're able to use in the field and get results within 30 to 40 minutes."
Murdock said the tests don't determine whether a body of water is safe. A negative result may just mean that toxins have not been detected at a specific site and at a specific time.
But when a positive test result occurs at a testing site, the group will give the public information "about mitigating their risk" at the site, she said.
The test result is also forwarded to the Department of Environment, who conducts more in-depth testing, and will notify the public of any site closures, Murdock said. The department did not respond to a request for an interview.
Blue-green algae is one of the potentially toxic cyanobacteria sometimes present in the St. John River and nearby watersheds. However, not all toxic cyanobacteria look blue-green, Murdock said.
Some appear in the form of benthic mats, which grow below the water's surface on rocks and sometimes drift up to the surface. Those mats are a grey-green, "yucky" colour, she said.
"It's very unpredictable," she said. "So it's good to test any cyanobacteria mat that we find, and sometimes [cyanobacteria] doesn't look like what you would think of for traditional blue-green algae."
Murdock said if the public notifies a watershed group of an algae bloom or a mat, tests will be done.
Toxins from cyanobacteria are a growing concern for many New Brunswickers, especially after four dogs were killed by them in 2018 and 2019.
Cyanobacteria can cause skin irritation, and when ingested, can be deadly.
Murdock said that not all cyanobacteria carry toxins. That's why these tests don't look for cyanobacteria but instead they check for toxins produced, specifically anatoxin-a, a neurotoxin, and microsystins, a liver toxin, the most prevalent toxins in New Brunswick, Murdock said.
"For our purposes, we're not trying to find the concentration of these toxins, but we're trying to determine whether the toxins are present in the cyanobacteria that we test," said Murdock.
The Atlantic Coastal Action Program in Saint John, ACAP, started a pilot program last year for the rapid cyanobacteria toxin test kits, and it was successful, according to Roxanne MacKinnon, executive director of the group.
For the duration of the summer, ACAP relaunched the monitoring program for their six different watershed partners, which incude Nashwaak Watershed.
The kits are available online for purchase although if anyone wants the same tests that ACAP has distributed, pricing information is only available upon request.
The tests were sold by Gold Standard Diagnostics. In an email, this group said that test kits are sold in boxes of either five or 20 test strips, and the cost ranges from between $25 to $50 per strip. The cost per strip is higher with a box of five tests, whereas it's lower for a box of 20.
Tests show results based on the faintness of the dyed strip. Because it relies of that, the test results are open to human interpretation. However, the tests still definitively say whether there are toxins from cyanobacteria present, said MacKinnon.
"These are really being used as a screening tool. As a screening tool, positive or negative is enough of an answer," she said.
More blooms occurring
Murdock said people have become more aware of cyanobacteria in recent years because there is more of it.
"It's when the weather gets really warm and muggy ... where we see those cyanobacteria blooms," she said.
But Murdock said that as temperatures rise because of climate change, cyanobacteria will only become more prevalent, and, as more cyanobacteria grow, testing will be even more necessary.
Corrections
- An earlier version of this story gave an incorrect portrayal of the value of rapid tests in determining the safety of water for swimming and other recreation. The test results are only relevant to a specific site and for a specific time. They won't determine the safety of a body of water.Jul 12, 2023 2:25 PM AT
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