Marrone Bio Innovations, Inc., a leading global provider of bio-based pest management and plant health products, announced the U.S. Environmental Protection Agency has approved Zequanox for open water use to combat invasive zebra and quagga mussels in lakes, rivers, recreation areas and other open bodies of water.
Zequanox, the industry's only selective and environmentally compatible molluscicide, was first approved by the EPA in 2012 for mussel control in enclosed systems and infrastructures for energy producers, manufacturing companies and golf courses.
With this new EPA approval, Zequanox now offers private waterfront owners and natural resource managers an effective solution to control existing populations of invasive mussels or knock back new infestations without the use of environmentally harmful potash and copper-based products.
Invasive mussel populations are now prevalent in major waterways throughout the country, including the Great Lakes Region as well as the Mississippi, Arkansas, Tennessee and Colorado rivers. The mussels have a significant economic and environmental impact on recreational water use. Colonies of invasive zebra and quagga mussels negatively impact native mussel populations, disrupt the natural ecosystem and cause proliferation of toxic blue-green algae. They decrease game fish populations, which can have a serious effect on the economic health of the fishing industry. Swimmers run the risk of injury from the invasive mussels' sharp shells, and water intakes from infested lakes and rivers used for irrigation, fire suppression and drinking water can suffer impeded or blocked flow and damage to infrastructure and equipment.
Additional economic challenges caused by invasive mussel infestations include decreased lakefront property values; loss of revenue from closed reservoirs and reduced recreation; and costs to remove or manage the infestation.
"We are extremely pleased that Zequanox is now available to lake managers and consumers," said Keith Pitts, vice president of Regulatory Affairs for MBI. "We have seen great success in enclosed systems, and now waterfront property owners and natural resources agencies have an invasive mussel control option that is more environmentally friendly than other solutions. The product can be administered without harming people, pets or the environment."
Zequanox is composed of dead cells derived from a naturally-occurring soil microbe, and it controls mussels in all life stages. Unlike toxic treatments, such as potash and copper-based solutions, Zequanox is biodegradable, noncorrosive and nonvolatile. In addition, Zequanox is highly selective to control only the invasive zebra and quagga mussels, is effective in a broad range of water conditions and, according to the EPA, its active ingredient has "low toxicity and presents little risk to non-target organisms."
Jessi DeMartini, research center coordinator with the Forest Preserve District of DuPage County, IL, was part of two collaborative open water studies at the Deep Quarry Lake in DuPage County in 2012 and 2013. Part of the Urban Stream Research Center in Warrenville, IL, DeMartini, along with partners from Southern Illinois University and MBI, tested Zequanox in two different objective trials and found the product to be effective in destroying the invasive mussel population within the treatment sites without harming surrounding species or the native ecosystem.
"The product is not damaging to aquatic life, humans or infrastructure," DeMartini said. "Zequanox produced high mortality of the zebra mussels — reaching 97 percent at the peak of application — while native fish exposed to the product remained unharmed. After further testing we concluded there were no lasting impacts to water quality."
Zequanox is applied directly into an open body of water, such as a lake or river, using standard injection equipment. Treatments can occur during any time of the day while people and pets are present and can be completed within hours. The product offers additional flexibility because it is proven to be effective in a broader range of water conditions.
The product offers a zero hour re-entry interval, so there is no waiting period after application that might interfere with commercial or recreational use of a waterway, such as fishing, swimming or boating. The U.S. EPA determined Zequanox was exempt from the requirement of a food tolerance, which indicates that there is no concern with using treated water to irrigate crops or that eating fish caught in waters treated by Zequanox poses any risk to consumers.
Further studies were conducted at Missouri State University and determined the product to be safe for native mussels, many of which are threatened and endangered species.
"Our lab experiments found that the product was non-toxic to the native mussels tested," said Dr. Chris Barnhart, professor of biology and native freshwater mussel expert at Missouri State University. "I could see this product being very useful for lake owners who have invasive zebra and quagga mussels on boats and docks. The product provides a much easier and more effective process for control when compared to scraping mussels off of a structure, and it apparently doesn't kill anything else, such as native mussels and other aquatic life. Another use for Zequanox could be treating native mussels during quarantine programs to ensure the absence of zebra mussels before transporting the native mussels to new waters."
Traditional chemical products do exist to effectively treat invasive mussel populations, however, they can leave damaging environmental impacts. Solutions containing potash (potassium chloride, KCI) and copper-based products can kill endangered and threatened native mussel species. Also, use of potash- and copper-based products lead to public heath concerns resulting in restricted drinking water use from reservoirs and prohibitions on recreational use for extended periods. Both chemicals are toxic to non-targeted organisms and persist in the environment, causing prolonged ecosystem exposure.
Marrone Bio Innovations, Inc. (Nasdaq:MBII) is a leading provider of bio-based pest management and plant health products for the agriculture; turf and ornamental; and water treatment markets. For more information, visit www.marronebio.com.