Ozonated Water: Vineyard Pest Control Without Chemicals

Midwest Wine Press Article | March 31, 2013 by Danny Wood

Until recently, the prospect of a grape growing industry in the Midwest without the use of chemicals may have seemed impossible. Throughout our region, insects, plant diseases and weeds thrive in the summer heat and humidity. Many grape growers say that without agricultural chemicals, they could not produce a consistent crop.

But some winemakers say the widespread reliance on chemicals has downsides for vineyards. In Kansas, David Sollo of Grace Hill Winery says, "Chemicals destroy the microbiological life in soils. They applied herbicides and pesticides for years and so the soil here is sterile!” He says, “There are no micro-organisms to help plants absorb nutrients”

They put on herbicides and pesticides for years and so the soil is sterile!

David Sollo, Grace Hill Winery, Kansas

While regulators consider approved agricultural chemicals safe if used properly, many widely used herbicides, fungicides and pesticides can carry risks and drawbacks, especially with repeated use or misuse.

For example, copper fungicides can be effective against powdery mildew; however, care must be taken due to the danger of foliage injury resulting from phytotoxicity. Some Midwestern grape growers also use fungicides with the active ingredient Mancozeb. One problem with Mancozeb is that it cannot be applied within 66 days of harvest.

According to the University of Illinois, there is also concern about fungicide resistance. Strobilurin fungicides are known by scientists to have a moderate to high risk for development of resistance if used improperly.

There can be health risks for farmers who apply chemicals. Ethyl Mercaptan fungicides are effective for downy mildew, but they have a four-day re-entry restriction after spraying. And the Captan brand fungicide label pulls no punches: “Do not allow persons to enter treated areas within four days following application unless a long-sleeved shirt and long pants or a coverall that covers all parts of the body except the head, hands, and feet, and chemically resistant gloves are worn.”

Popular carbaryl based pesticides have been known to cause, ”burns from direct skin or eye contact, nausea, stomach cramps, diarrhea, and excessive salivation through inhalation or ingestion,” according to the Toxicology Network.

Some studies link pesticide exposure to higher rates of diseases among farmers. For example, a study by researchers from the National Institute of Environmental Health Sciences (NIEHS), ‘Incident Diabetes and Pesticide Exposure Among Licensed Pesticide Applicators: Agricultural Health Study 1993 – 2003′, linked specific pesticides with an up to 200% increased risk of diabetes.

Another indication of the health risks: the ‘Midwest Small Fruit & Grape Spray Guide 2012,’ edited by Purdue University’s Bruce Bordelon with Mike Ellis and Celeste Welty from Ohio State University, has very strict handling instructions for all pesticide chemicals: ”Use an adequate respirator and protective clothing, especially when mixing pesticides.”

Another recommendation in the same document reads: “For maximum safety, get an appropriate blood test before the season starts and test periodically during the season.”

Not all vineyards in the Midwest follow these guidelines, but many do. For example, workers at one of the region’s bigger wine makers, Les Bourgeois Vineyards, always use spray-suits with respirators when applying pesticides and fungicides. Each barn on the property has a station for workers to wash down after chemicals have been applied.

Enter Ernie Wilmink, a very tall Dutchman with a presence and manner reminiscent of Arnold Schwarzenegger.

A consultant in ozone technology for more than four decades, Wilmink says wineries and vineyards can drastically reduce chemicals with ozogation; using an ozonated water spray to disinfect their wineries and control vineyard pests.  The ingredients that produce this aqueous ozone spray are very simple: “The only thing that I use,” says Wilmink, “is electricity and the air we breathe.”

At recent wine industry conferences across the Midwest, Wilmink’s brightly painted AgriOzein trailer was often seen in parking lots. In fact, Wilmink says during the last year he’s traveled over 10,000 miles, attending six wine conferences to give talks on ozogation and sell the apparatus that performs it.

On trade show floors, his yellow-tanked spraying machine – or Multifunction Mobile Ozone System – sat on its trailer. Echoing the famous former Californian governor, he calls this his “ozonator.” Ozogation, Wilmink says, is a “thunderstorm in a box.”

That’s because his process for making ozone is similar to lightening during a thunderstorm. In fact, the clean odor after a thunderstorm is caused by lightening passing through the atmosphere and forming ozone.

“The only thing that I use,” says Wilmink, “is electricity and the air we breathe.”

The AgriOzein technology is relatively simple. First, Wilmink’s ozonator separates air into nitrogen and oxygen. Then, inside a metal box, an electrical discharge converts the nitrogen/oxygen gas into pure oxygen, a three atom molecule called 03 or ozone. This three atom molecule is much less stable than the two atom oxygen we breath and doesn’t last very long before reverting to the same oxygen found in air.

According to the results of ozone decay experiments by Christopher Weilandics published in Holland in 1988, the half-life of ozone is 37 minutes. This duration is often quoted by ozone products companies. During its short life, ozone’s powerful oxidation properties make it a good disinfectant and, according to Wilmink, a lethal killer of vineyard pests.

Wilmink elaborates on what he thinks it can do for a vineyard: “Compare it with chlorine for example. Ozone is five thousand times faster in killing bacteria than chlorine and has no by-products, it’s just pure nature. So when you combine it into water, it has a half-life of about 25 minutes and everything issues back to oxygen.” He continues, “As soon as you spray it over these vines, it takes a fraction of a second to take care of the disease or insects that are there.”

Where it all happens, the "thunderstorm in a box"

Ozogation kills these pests through cellular lysing, a biological process of destroying a cell’s walls by oxidizing its enzymes, proteins, DNA and RNA. Many studies have documented this oxidation process.

For example, according to a 2011 study by M. N. Rojas-Valencia from the National Autonomous University of Mexico, “Owing to its oxidizing properties, ozone is currently known as one of the most efficient and fastest microbicides. The evidence has shown that it can break cell membrane or protoplasm, making it impossible to activate bacteria, virus and protozoa cells while removing up to 99% of bacteria and viruses at 10 mg/l in 10 minutes.”

Wilmink says ozogation is a completely clean technology capable of killing any sort of vineyard bug and can totally replace the use of pesticides. “Beetles to powdery mildew, there is nothing that can withstand the strength of ozone technology,” says Wilmink.

He says his multifunction unit is a turn-key operation – all you need is water in the tank and gas in the generator and 15 minutes later you are spraying.

It might sound too good to be true, but the Dutchman is supported by Professors Max McFarland and Paul Read from the University of Nebraska at Lincoln. For all three men, this venture is about more than turning a profit and providing an alternative to chemicals, it’s about moving the wine industry towards a greener future.

“…it takes a fraction of a second to take care of the disease or insects that are there.”

Ernie Wilmink, President, AgriOzein, Consultants in Ozone Technology

Wilmink says there are about 40 wineries that use his equipment inside their wineries to sanitize their equipment and at least seven are now using it in the vineyard too.

The first significant trials of the technology on vineyards were completed last year at Mac’s Creek Winery & Vineyards in Nebraska. According to the test results on dozens of Marechal Foch vines divided into three groups, by the end of last September, only 2% of the vines that were ozogated during 2012 showed any sign of insects. That compared with 38% of vines in a second, control sample, and, interestingly, 93% of vines in a third group to which a chemical was applied. The ozogated vines also did better controlling diseases during the season, but by the end of the growing season, disease pressure on all three groups was about the same.

However, last year was particularly dry and disease and insect pressure was not typical. Professor McFarland is impressed with the results so far, but wants to do further ozone testing in wetter, more ‘normal’ seasonal conditions.

Wilmink says he has all the approvals required by the US Food and Drug Administration (FDA) and the US Environmental Protection Agency (US EPA) for ozogation to be used both inside wineries and on grapevines. However, the two federal regulators appear confused about how their respective regulations pertain to ozone use in agriculture.

The common use of ozogation as a winery sanitizer is not an issue. Dennis Edwards, Branch Chief in the Antimicrobial Division of the US EPA confirmed that the ozonator device does not need to be registered. However, using the process on crops, like grapes, means ozogation may need to satisfy more regulations, depending on how it is defined.

According to FIFRA (Federal Insecticide, Fungicide, and Rodenticide Act), a pesticide is “any substance or mixture of substances intended for preventing, destroying, repelling, or mitigating any pest.” Under the FFDCA (Federal Food, Drug, and Cosmetic Act) there are exclusions from the above definition but not if the substance – in this case the ozonated water – is used on a raw agricultural commodity, or, “The substance is applied in the field.”

In an email response to questions, the US EPA media office said, “ozone is a pesticide” when produced by a “pesticidal device” like the one Wilmink uses.

So if ozone is a pesticide, some viticulture experts say Wilmink needs to submit residue tolerance and residual data information to the EPA so it can decide whether or not to approve this new application of ozonated water in the vineyard. Wilmink says the Pesticide Bureau at the Iowa Department of Agriculture and Land Stewardship has also said he needs to submit this information.
Gretchen Paluch, Pesticide Bureau Chief at the Iowa Department of Agriculture, in an email response to questions from Midwest Wine Press, said:

“..the issue pertaining to tolerance is Section 408 of the Federal Food Drug and Cosmetic Act. It states that any pesticide chemical residue on or in food will be deemed unsafe unless there is a tolerance for the residue or an exemption from a tolerance.”

Paluch directed Midwest Wine Press to the US EPA Antimicrobials Division. The US EPA media office said:

“If a pesticide is to be used on a food crop or in a manner that will result in residues in a food or animal feed, the FFDCA requires that the EPA establish a tolerance, or maximum legal residue level, or an exemption from the tolerance requirement for that food or feed.” The US EPA also said, “use of ozone to treat a raw agricultural commodity in the field is a pesticidal food use, which is subject to the FFDCA.” They said the residuals approvals process in this case is the FDA’s jurisdiction and referred Midwest Wine Press to them.

The FDA’s Veterinary and Cosmetic Products, Office of Media Affairs said: “The use of ozone in water on grape vines in the field with the intent of controlling pests and diseases is under the regulatory authority of the Environmental Protection Agency.”

In response to these vexing regulatory issues, Wilmink argues that ozone is not a pesticide. He quotes a number of FDA rulings. For example, the GRAS – Generally Recognized as Safe – designation was given to ozone for use in bottled drinking drinking water in 1982 and again in 1997 for use as a disinfectant in food processing. Wilmink’s conclusion is that if ozone is already legally used as a disinfectant for drinking water and food, it is surely legal for use on vines and grapes.

He says under FIFRA, “chemicals are defined as materials that are manufactured, packaged, transported, stored and applied” and concludes that ozone, as an unstable gas that must be generated and used on site, does not fit that criteria. In any case, Wilmink says, ozogation produces no lasting residuals so there is nothing to submit to the regulators.

Experts like Professors Rip G. Rice and Dee M. Graham, private sector consultants who conducted research into the use of ozone in agriculture and food processing, agree with Wilmink and seem to disagree with the US EPA’s interpretation of FIFRA.  As stated in their 2001 paper, U.S. FDA Regulatory Approval of Ozone as an Antimicrobial Agent – What Is Allowed and What Needs to Be Understood: “Ozone is not a pesticide within the meaning of the Federal Insecticide, Fungicide, and Rodenticide Act.”

They go on to say: “…the use of ozone applied in the gaseous form or in aqueous solution on raw agricultural commodities is consistent with section 201(q)(1)(B)(i) of the Federal Food, Drug, and Cosmetic Act.”

However, there is some reluctance from fruit growers to use ozonated water sprays based on concerns that atmospheric ozone can damage vines. A paper by Fritz Westover from Texas AgriLife Extension discusses “oxidative stipple of grape leaves as the result of high atmospheric ozone levels.” Other research by the US FDA, Effects of Ozone Air Pollution on Plants, says, “ozone pollution…causes more damage to plants than all other air pollutants combined.” In addition,  Dr. Dean Volenberg at the University of Wisconsin published a report on atmospheric ozone vineyard damage during last summer in Wisconsin.

See related story: Ozone Damage to Grape Leaves

In response, Wilmink says ozone leaf damage reports are related to tropospheric ozone, a problem created by air pollution interacting with sunlight. Ozogation, he says, "uses very small amounts of ozone compared to the amounts produced by a lightening strike: “AgriOzein’s units apply the ozone in an aqueous state at very low doses.”

…all their tests in the vineyard “showed absolutely no injury due to ozogation.”

He adds that research by Professors Max McFarland and Paul Read and all their tests in the vineyard “showed absolutely no injury due to ozogation.” Also, says Wilmink, vines can be exposed to tropospheric ozone for up to 24 hours – ozogation exposure only lasts seconds. For further reading on this topic, he recommends the book “Tropospheric Ozone, Human Health and Agricultural Impacts” (1993) by David J McKee.

The “Ozonator” is currently spreading the word about “ozogation” at meetings and conferences in Germany, Holland and France. He says in Europe there’s considerable interest in his process and its regulators are more enthusiastic about cleaner, greener options that can reduce the use of chemicals in agriculture, including vineyards.