Food Safety / Pest Control

Chemicals' Role In Pest Control Is Shrinking

Infestations demand pesticides, but routine fumigation is becoming a thing of the past in food and beverage plants.

By Kevin T. Higgins, Managing Editor

Like “law and order” and “business friendly,” natural and organic are attractive tags in part because of the implication that anything else is un-natural or inorganic, neither of which is a desirable trait when it comes to food and beverage products.

The promise of chemical-free formulation and processing is part of the appeal of organic foods, of course, and food activists are using social media to pressure mainstream food companies to adopt a similar approach.

Fretting about blanket condemnations of preservatives such as benzoic acid and sorbate, food scientist Michael Doyle dubbed the phenomenon “chemophobia” in an address to pest control professionals at Pest Invasion 2017, an annual seminar sponsored by McCloud Services (, South Elgin, Ill.

Doyle was concerned about the human health implications of chemophobia. By bending to the will of bloggers and other critics, food companies inadvertently raise the likelihood of recalls of preservative-free baby food and other products due to microbial spoilage, he said.

Chemophobia has helped transform organic foods from a sales blip into a $47 billion business, about 5 percent of all U.S. food sales. Mainstream supermarkets, not health food stores, sell most of those products, and while their buyers aren’t pressuring pest control specialists to cut back on pesticide use, that is, in fact, what is happening.

“There are times when pesticides are absolutely necessary,” allows consultant Al St. Cyr, “but it’s a short-term solution to a long-term problem.” If an infestation occurs and remedial action is required, the use of insecticides and rodenticides becomes necessary. However, section 117.35(c) of the current Good Manufacturing Practices make it clear that any infestation is the result of a failure of the pest control program. Chemicals are a last resort, not a first or even third option.

As president of ASC Consulting in Manhattan, Kan., and quality manager for the Food Protection Alliance (, St. Cyr has four decades of experience working with food companies on sanitation and sanitary design, as well as integrated pest management (IPM). Fogging and chemical treatments are extreme measures that should only be deployed when all else has failed, he notes. “In the FSMA GMPs, no pests are allowed in any food plant,” St. Cyr points out. “Zero is what we want.”

One measure of pesticides’ shrinking role can be seen in container size. “Thirty years ago food plants ordered chemicals in 55-gal. drums,” muses St. Cyr. “Now, chemicals come in quart containers and even smaller.”

Zero chemicals may not be possible. Even standards for organic food production make allowances for them, although it’s a short list of permitted compounds. Cholcalciferol, also known as vitamin D3, a human health supplement, is allowed for rodent control, while boric acid is the go-to insecticide.

Few if any mainstream food manufacturers follow the pest control protocols of USDA’s National Organic Program (NOP). Pest control experts say the chemicals allowed and the application requirements vary considerably between organic certification bodies. Nonetheless, the objectives of NOP constitute best practices in mainstream pest control for any processor wrestling with chemophobia.

From control to prevention

With or without FSMA, pest prevention is today’s priority, says Judy Black, vice president-technical services for Rentokil Steritech (, Charlotte N.C. The progression has gone from pest control to pest management and finally to a preventive, or proactive, approach. Environmental responsibility was a core value at the Steritech Group prior to its acquisition by UK-based Rentokil, and that remains a hallmark of its approach to pest prevention.

“The general public views the pest management industry as an industry that applies a lot of chemicals, but the reality is, we don’t,” maintains Black.

Effective prevention is impossible if a facility does not have an effective sanitation program and good housekeeping practices. Steritech began conducting sanitation audits in 1995, and Rentokil Steritech technicians bring that expertise to bear when they review plant conditions and possible contributors to pest problems such as missing door sweeps and unfilled cracks and crevices to the outside.

When problems surface, a review of existing sanitation practices makes more sense than chemical fogging. If insects are emerging from a floor drain, for example, increasing the frequency of drain cleaning is a better remedy than insecticide.

An inverse relationship exists between chemical use and the amount of interaction and cooperation between pest control technicians and plant personnel, Black suggests. The good news is that plant personnel have become much more responsive in recent years, an attitude change largely driven by stricter food safety standards.

“FSMA brought dramatic changes in attitudes,” she says. Recommended changes in storage practices or needed repairs really can’t be ignored because of documentation requirements. “We were on our way there, and FSMA helped us get to the finish line,” says Black.

Plant-based essential oils from garlic, clove, cinnamon and chrysanthemums are the active ingredients in a number of pesticides, points out Patricia Hottel, technical director at McCloud Services. Despite their non-chemical “natural” appeal, they are nonetheless toxic.

Chrysanthemums are the basis of pyrethrum, the most commonly used fumigant. Once a common practice, fumigation now is done sparingly, concurs Jerry Heath, product manager and staff entomologist at IFC ( in Lenexa, Kan. That translates to lower expenditures for the chemical.

A greater financial benefit is the reduction in downtime to conduct fumigation. St. Cyr cites the example of a client that was scheduling 10 plant fumigations a year, each requiring a three-day shutdown. “The cost of not being in production 30 days a year couldn’t be justified,” he says. Fumigation had become a crutch and an excuse for not taking the preventive steps that would have made fumigation unnecessary.

The F in IFC actually stands for Fumigants. The company’s roots are in protection of stored grains, which might require fumigation when heat treatment and preventive steps fail. “There was a time when we considered changing our company name,” says Heath, over concern “that it was out of touch with the times.”

Natural born disrupters

The same can’t be said of pheromones and insect growth regulators (IGR), two alternatives to chemicals favored by Heath and other entomologists.

Also known as mating disruptors, pheromones have been part of pest control’s food protection arsenal for almost a decade. Pheromones that emulate the scent of female Indian meal moths are the most prominent example, and a handful of other insects can be targeted with pheromones. “It’s amazing how well they work,” he testifies, though the handful of species that can be targeted limits their use.

IGRs typically are used in fogging and aerosol applications and require contact with larvae. One of the first was Gentrol, which was introduced in the late 1990s. Despite its effectiveness, Gentrol applications peaked a few years later, not because of ineffectiveness but because of perceptions.

“You didn’t see dead insects lying on their backs, and that made it a hard sell,” Heath recalls. He credits the introduction of bar code systems for monitoring pest activity for reviving IGR use. Those software programs shifted attention to actual insect activity and away from bug carcasses as a measure of pest control success.

Regardless of whether IGRs, chemicals or other remediation are applied, the scope of the application likely will be focused, according to Chelle Hartzer, technical services manager for Orkin Commercial Services (www.orkin/, Atlanta. “Certainly, we’re not going to use fumigation as our first approach, and when we do use it, it is going to be in very localized areas,” she says.

If any retailers or foodservice operators are discouraging processors from chemical use, pest professionals say they are unaware of it. “It’s an attractive marketing idea,” allows Heath, “but pesticide use is pretty minimal in the food processing industry.”

Brand protection is a stronger incentive for sparing use in localized areas. General Mills got a bitter lesson in 1994 on the careless use of Dursban. A contractor improperly applied the chemical to stored oats, triggering recalls and the dumping of 4,000 truckloads of Cheerios and other cereals in landfills.

In some cases, pesticides can work against other tactics. Putting rodenticide in a bait station might result in a phenomenon that Hottel terms “dead mouse walking.”

Because the poison takes time to work, the location of a dead mouse or rat would unlikely be found where the vermin gained entry.

Elimination of chemical use in pest control is not desirable or necessary, pest control experts agree. But while they do not suffer from chemophobia, neither are they chemophilic. When all else fails, chemicals may be the last resort to keep a plant in production. But if a program is working properly, chemical use will be infrequent.