New testing method could make phosphorus monitoring cheaper, faster

Phosphorus is usually at the forefront of concerns about the health of Lake Erie. While watershed managers never stop searching for ways to reduce phosphorus input, they also need to be able to monitor current levels easily and cost-effectively.

Chris Spiese of Ohio Northern University (ONU) is working on just this kind of rapid phosphate detection -- phosphate is the most common form of environmental phosphorus, and most of it comes from agricultural runoff. Funded by Ohio Sea Grant, Spiese and undergraduate student Joanne Berry are testing a reagent that quickly produces yellow-green fluorescence when phosphate is present. That fluorescence can then be detected with standard lab equipment.

"The traditional detection method for phosphate is kind of cumbersome," said Spiese -- each sample can also cost about $50 to test. "Our goal was to find a better, faster, cheaper method of measuring phosphate."

Once the protocol is perfected and published, Spiese will provide it to Ohio EPA for further evaluation and potential adoption.

Spiese and Berry created six different versions of a compound presented in a 2011 journal, and after some trial and error, they settled on a variant of the original molecule, which reliably fluoresces when a sample contains phosphate.

Eliminating interference from other ions usually present in water samples is an important step in the project as well. Spiese and Berry have ruled out interference from most compounds that affect the traditional testing method. "We got down to the point where we were struggling to find compounds that would actually interfere," said Spiese, an assistant professor in the Department of Chemistry and Biochemistry at ONU.

In addition to that specificity, the method is much cheaper than the current test. Once the protocol is perfected and published, Spiese will provide it to the Ohio Environmental Protection Agency for further evaluation and potential adoption.

Next: Volunteers, students to be involved

Spiese also plans to involve volunteers from the Blanchard River Watershed Partnership and local high schools in a one-day sampling effort this spring. Volunteers will take samples across the watershed, which will then be tested in Spiese's lab using both the traditional technique and the faster, more cost-effective method.

"Our goal is to get sampling all along that watershed, and interface with local schools and the community to really get them involved, to get the students exposed to doing real environmental research," Spiese said. "It's going to be a blast if we can recruit enough people."

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-- Christina Dierkes, Ohio Sea Grant Communications