WC138 SeptOct 2024 - Flipbook - Page 16
WASTEWATER
Research overview
In 2019, Genome BC had a call for proposals to validate and
drive the adoption of environmental DNA (eDNA) technologies
by industry and government organizations. This is an established, accurate, and rapid method of species identification and
tracking that’s gaining importance across many sectors, from
species biodiversity investigations to environmental monitoring and assessment. As a result of all this adoption, the cost of
eDNA analysis is low (which is also spurring further adoption),
now similar to other monitoring methods.
In 2021, Hallam and Ziels were awarded funding for a project
to examine BFB in activated sludge.
In short, they’ve shown that the ability to accurately detect BFB based on eDNA signatures has major potential for
operational cost savings to B.C. wastewater treatment plants by
informing more precise dosage of chlorine — but they’ve discovered other things too.
Hallam and Ziels first talked with leaders at the Vancouver
wastewater treatment plants to learn more about current big-picture pressures.
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WATER C AN ADA • SEP TEMBER/OCTOBER 2024
“We have a changing climate and a growing population, and
this is putting pressure on wastewater plants to remove nitrogen
and meet other additional requirements,” said Ziels. “All of this
relies on complex bacterial communities, but we didn’t know
much about how these bacteria are functioning on large scales
in a plant environment. We wanted to see how eDNA analysis
could help identify the microbes present in the system, how the
communities work, and how they affect the activated sludge
process. Then we would be able to give solid data for technicians
to decide how best to minimize or eliminate problems.”
Of particular concern is the need in the activated sludge
process for microbes to settle so that they are not flushed into
the environment. But Ziels explains, “as those in the industry
know, there are bacteria that don’t settle, but foam. It’s a major
headache for plants in terms of effective water treatment and
these problematic organisms also drive costs up.”
Identifying these organisms using the traditional microscope
method requires skill as they can look very similar. Because not
everyone using this method is equally skilled, there is quite a bit
of mistaken identity. It’s also time consuming.
WAT E R C A N A D A . N E T
GenomeBC
Dr. Ryan Ziels, an associate professor in Civil Engineering and Environmental Engineering at UBC, left, and Dr.
Steve Hallam, co-leader of the study and a professor
in UBC’s Department of Microbiology and Immunology, display the Nanopore MinION handheld portable
device that sequences nucleic acids such as RNA and
DNA. Unlike the second generation of sequencing, the
third generation of sequencing technologies allows
researchers to analyze nucleic acids at a single molecule
resolution and in real-time.
Nucleic acids are passed through an electrically charged
nanoscale pore (nanopore), and the identity of each
nucleotide is determined by a drop in electrical current
unique to each nucleotide base (A, T, U, G, C). This
novel sequencing approach and miniaturization has
enabled researchers to sequence outside traditional lab
environments.
