Should Microcystin be Micromanaged?

Many water operators are struggling with microcystin. How should it be treated? How will the EPA manage it? And better yet — what can be done to prevent microcystin contamination in the first place?
Should Microcystin be Micromanaged?

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Algae blooms, microcystin, do-not-drink bans, toxins. Those buzzwords have floated across the lips of many municipal leaders this summer, especially after a do-not-drink ban affected more than 400,000 people in Toledo, Ohio. But even though the topic has been widely discussed, water operators still have many questions and few answers. Microcystin remains an elusive topic.

The EPA has not published microcystin regulations, and the agency has provided relatively little information on how to measure and treat the toxin. Some states — specifically Florida, Minnesota, Ohio, Oklahoma and Oregon — have created their own standards, which rely on suggestions from the World Health Organization. But water operators in other states, including Texas and Iowa, are struggling to identify proper testing methods, acceptable levels and effective treatments.

Opinions from the water industry
Although some water professionals are wary of hastily created regulations, they are equally wary of hastily produced information.

"The presence of regulations does not mean a utility will be able to predict a toxin episode," says Tom Conry, water quality manager for Waco (Texas) Water Utility Services. "Standards for specific toxins could be helpful. However, some cyanobacteria do not always either produce a toxin or — to my knowledge — a calculable concentration consistently. Too much is unknown.

"Information is normally helpful,” Conry says. “However, instances where incomplete information is used to set goals or recommendations are cost-prohibitive and waste time, while misinforming the utilities and the public."

His recommendation to the EPA? "Provide good science for public consumption, not 'crisis du jour.'"

"Whether something is regulated or not, we as water producers are responsible for the safety of the finished water that we deliver," says William Stowe, CEO and general manager of Des Moines (Iowa) Water Works. "The fact that there is no Safe Drinking Water Act requirement from the EPA on cyanobacteria and microtoxins creates a real health concern in communities. As such, we have a larger responsibility than the regulations hand to us."

As far as Stowe is concerned, the larger issue is phosphorus and nitrogen that enter the water and create the problem. "The emphasis of regulation should be on the front end, not the back end," he says.

In addition, Stowe believes the water industry should not overreact and pressure the EPA to regulate contaminants without comprehensive risk assessments and cost/benefit analysis.

EPA reaction
What is the EPA doing about microcystins? On Sept. 3, the agency announced the Great Lakes Restoration Initiative (GLRI) will provide almost $12 million to federal and state agencies to target harmful algal blooms in western Lake Erie.

In addition, according to Robert Daguillard, EPA media relations representative, the agency has been evaluating microcystins and other contaminants associated with algal blooms to develop guidance for state and local officials. The EPA is also working to reduce nitrogen and phosphorus pollution problems.

Specifically, the EPA is developing drinking water Health Advisories (HAs) for microcystin-LR and cylindrospermopsin, two of three cyanotoxins listed on the third Candidate Contaminant List (CCL 3).

"HAs are informal technical guidance designed specifically to help federal, state and local officials — and managers of public or community water systems — to protect public health," says Daguillard. "In addition to toxicity, the HA documents summarize currently available treatment techniques and analytical methods."

The EPA expects to publish these technical guidance documents by 2015.

Furthermore, every five years, the EPA must issue a new list of no more than 30 unregulated contaminants to be monitored by public water systems. According to Daguillard, the agency is considering the inclusion of cyanotoxins, including six particular microcystin variants/congeners, in the fourth round of the Unregulated Contaminant Monitoring Rule (UMCR 4).

"UMCR 4 monitoring is scheduled to take place starting in 2018," he says. "It will inform the agency's determination on how frequently the contaminant occurs in drinking water and at what levels."

For the present
In the meantime, what should operators do?

"Once cyanobacteria and/or their cyanotoxins are detected in the surface water supplying a drinking water system, the operators of the facility must act to remove or inactivate them," says Daguillard. "The utility must determine the growth patterns and species that dominate the bloom in order to determine the most effective treatment process. Drinking water utilities can undertake different management strategies to deal with the blooms, such as accessing alternative sources of water, adjusting intake depth to avoid drawing contaminated water, and using pretreatment at the intake or during the treatment process."

And, according to the U.S. EPA's "Drinking Water Treatability Database" for microcystins, several processes are considered effective for the removal/oxidation of microcystins. The five most effective are ozone (up to 100 percent), ozone with hydrogen peroxide (up to 100 percent), membrane separation with reverse osmosis (up to 99 percent), membrane filtration with ultrafiltration (up to 98 percent), and powdered activated carbon (up to 100 percent for some microcystins, but less for others).

Congress is also working on a solution. In September, Michigan's U.S. senators announced a $653,000 grant to the University of Michigan to develop tools to forecast algae blooms in the Great Lakes. Also, Rep. Marcy Kaptur (D-Ohio) introduced the Safe and Secure Drinking Water Act, which requires the U.S. EPA to publish recommendations — but not regulations — for microcystin levels as well as suggest procedures for testing and treating affected waters.

However, according to Stowe, industry professionals should not rely solely on the EPA. They should also rely on each other.

"Despite a shortage of information, there is enough 'collegiality' in the water utility community and within our professional associations when issues such as this arise that we can work together," he says. "We will never be in a situation, regardless of how good the science is, that we have anticipated every risk and engineered around it. As a result, those of us in this work really need to continue to cooperate with each other and learn what everyone's experiences have taught them."


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