California Approves MBI' Zequanox® for Invasive Mussel Control

Marrone Bio Innovations, Inc. (MBI), a leading global provider of bio-based pest management products for agriculture and water, announced recently that the state of California has issued a Certificate of Pesticide Registration for Zequanox® to control invasive zebra and quagga mussels (Dreissena species) in pipe systems and infrastructure. Under this registration, Zequanox can now be used as an effective, environmentally responsible alternative to toxic, broad-spectrum chemicals (such as chlorine) to treat irrigation lines and water conveyance structures, as well as cooling and process water systems of industrial and power generation facilities.

Invasive quagga mussels were first discovered in California in 2007. They entered the state via aqueducts that transport water from the Colorado River to Southern California for agriculture irrigation and drinking water. In 2008 zebra mussels—the cousin of the quagga—were identified in San Justo Reservoir in San Benito County. In response to this discovery, the reservoir was closed to all recreation to prevent the spread of zebra mussels to surrounding water bodies.

Dr. Sarahann Rackl, director of MBI’s water technologies, described the unique challenge facing California: “The state of California is particularly vulnerable to infestation. It not only has a vast network of water distribution, which can aid the spread of the mussels, it also experiences warm water temperatures throughout most of the year, which accelerates mussel growth and can extend the mussels’ reproductive period.”

Zequanox is the industry’s only US EPA-approved, biological molluscicide for controlling zebra and quagga mussels. It is composed of dead cells from a ubiquitous soil microbe. It is highly selective and has been proven to be lethal to Dreissena species without harming humans, infrastructure, non-target species or the environment. According to the EPA, the product’s active ingredient has “low toxicity and presents little risk to non-target organisms.”

Zequanox can be used to control adult mussels as well as reduce settlement, and it has been shown to provide a level of efficacy comparable to chlorine and other chemical treatments. Unlike those toxic chemical treatments, Zequanox is biodegradable, noncorrosive and nonvolatile.

Dr. Rackl added, “Zequanox is also food-tolerance exempt (no maximum residue limit). Water treated with Zequanox can be used to irrigate crops, for fishing or for any other uses that might result in food, feed or drinking water contact. This benefit is particularly important in a state such as California, which relies heavily on a water distribution network to meet the demands for agricultural irrigation and municipal water.”

Dr. Rackl concluded, “We are very pleased that California has registered Zequanox, as it offers an invasive mussel control alternative that reduces chemical use and associated regulatory burdens, requires little to no capital investment or equipment maintenance, and can be employed without harming employees, equipment or the environment.”

Zequanox is currently registered in 26 states; additional state registrations are pending.