Bed Bug Herbal Remedies Work Well With Traps

July 15, 2013

THE NEEM TREE (Azadirachta indica), a medicinal mahogany tree (Meliaceae) native to arid broadleaf and scrub forests in Asia (e.g. India), has been used for over 4,000 years in Vedic medicine and has a heavy, durable wood useful for furniture and buildings because it is resistant to termites and fungi. Nonetheless, despite US EPA registration as a pesticide for crop and home use and a long legacy of neem seed oil use for cosmetics, shampoos, toothpastes and medicines in India, Ohio State University researcher Susan Jones could not find any households near her Columbus, Ohio, home willing to try neem in her bed bug control experiments.

“We had no study takers because of the regulatory requirements,” which scared off people, Jones told the Entomological Society of America (ESA) Annual Meeting. “You have to read page after page to residents about toxicity without being able to talk about the toxicity of alternative products” not as safe as neem. In October 2012, an empty house with bed bugs became available for research when its occupant opted to escape a bad bed bug infestation by leaving the infested home; and inadvertently transferred the infestation to their new home.

Jones monitored the empty house by placing in each room four (4) Verifi(TM) CO2 (carbon dioxide) traps and four (4) Climbup(R) Interceptor traps. Visual inspections revealed few bed bugs. On October 24, 2012, prior to neem treatments, 38 bed bugs were captured in Climbup(R) traps, indicating bed bug infestations only in the master bedroom and bed of the empty house. Eight Verifi(TM) traps captured 48 bed bugs in the dining room, guest room and master bedroom. As part of an IPM (integrated pest management) approach using multiple treatment tools: Electrical sockets were treated with MotherEarth(R) D diatomaceous earth; 3.67 gal (13.9 l) at a rate of 1 gal/250 ft2 (3.9 l/23 m2). Gorilla Tape(R) was used to seal around the doors and exclude bed bug movement from other rooms.

The neem seed oil product, Cirkil(TM) RTU, was sprayed in various places, including on books, backs of picture frames and cardboard boxes. Vials of the insecticide-susceptible Harlan bed bug strain were placed around the house for on-site neem seed oil vapor toxicity assays. Two days after spraying, bed bug mortality from neem seed oil vapors was highest in confined spaces; with 48% mortality in vials placed between the mattress and box spring, versus 28% mortality in open spaces. On Nov. 6, two weeks post-treatment, 123 dead bed bugs were vacuumed up and live bed bugs were detected in a second bedroom. Bed bug numbers were low because the monitoring traps were doing double duty, also providing population suppression by removing many bed bugs.

Herbal oils can also be combined with heat chambers at 50 C (122 F) or carbon dioxide (CO2) fumigation chambers to combat bed bugs. However, heat chambers are expensive, and CO2 fumigation with dry ice can pose handling difficulties and room air circulation issues, Dong-Hwan Choe of the University of California, Riverside, told the Entomological Society of America (ESA).

Herbal essential oils are useful against head lice, and in Choe’s native Korea clove oil from from the leaves and flower buds of clove plants (Syzygium aromaticum) is used in aromatherapy and as a medicine. Clove oil is rich in GRAS (Generally Recognized as Safe) compounds such as eugenol, beta-caryophyllene and methyl salicylate (sometimes called wintergreen oil), which are useful as vapors in control of insects and microbes. In dentistry, clove oil (eugenol) is widely used as an antiseptic and pain reliever.

Clove essential oils work faster in closed spaces or fumigation chambers (e.g. vials, Mason jars) than in open spaces. Essential oils are even slower to kill bed bugs when orally ingested. In experiments at varied temperatures, Choe placed 10 bed bugs in plastic vials with mesh tops. The vials were placed inside 900 ml (1.9 pint) Mason jars; filter paper treated with essential oils was placed on the underside of the Mason jar tops.

Herbal essential oils worked faster at higher temperatures. For example, methyl salicylate fumigant vapors provided 100% bed bug mortality in 30 hours at 26 C (79 F); 10 hours at 35 C (95 F); and 8 hours at 40 C (104 F). Eugenol vapors produced similar results; there were no synergistic or additive effects from combining eugenol and methyl salicylate. Choe told the ESA that his future trials will include: botanical oil granules; exposing bed bug-infested items to essential oil vapors; and checking for sublethal essential oil effects on parameters such as female bed bug reproduction.

Narinderpal Singh of Rutgers placed bed bugs on cotton fabric squares treated (half left untreated) with synthetic pesticide and herbal essential oil products: 1) Temprid(TM) SC, a mixture of imidacloprid and cyfluthrin (neonicotinoid and pyrethroid insecticides); 2) Ecoraider(TM) (Reneotech, North Bergen, NJ) contains FDA GRAS ingredients labeled as “made from extracts of multiple traditional herbs that have been used in Asia for hundreds of years for therapy and to repel insects;” 3) Demand(R) CS, which contains lambda-cyhalothrin (a pyrethroid insecticide); 4) Bed Bug Patrol(R) (Nature’s Innovation, Buford, FL), a mixture with the active ingredients listed as clove oil, peppermint oil and sodium lauryl sulfate.&&

Temprid(TM) SC and Demand(R) CS proved best on the cotton fabric test. In arena bioassays with Climbup(R)Interceptor traps, none of the four insecticides were repellent to bed bugs (i.e. repellency was less than 30%). Ecoraider(TM) was equal to Temprid(TM) SC and Demand(R) CS against the tough to kill bed bug eggs. Singh concluded that field tests of Ecoraider(TM) as a biopesticide were warranted.

Changlu Wang of Rutgers told the ESA that travelers might be protected from bed bug bites and bring home fewer bed bugs if protected by essential oil repellents, as well as by more traditional mosquito and tick repellents like DEET, permethrin and picaridin. Repellents are more convenient and less expensive than non-chemical alternatives such as sleeping under bed bug tents and bandaging yourself in a protective suit.

Isolongifolenone, an odorless sesquiterpene found in the South American Tauroniro tree (Humiria balsamifera), is among the botanicals being studied, as it can also be synthesized from turpentine oil and is as effective as DEET against mosquito and tick species. Bed bug arena tests involve putting a band of repellent around a table leg, with a Climbup(R)Interceptor trap below. If the bed bug falls into the trap, it is deemed to have been repelled from the surface above. In actual practice, the bed bug climbs up the surface and goes horizontal onto the treated surface and drops or falls off if the surface is repellent. Isolongifolenone starts losing its repellency after 3 hours; 5%-10% DEET works for about 9 hours. In arena tests with host cues, 25% DEET keeps surfaces repellent to bed bugs for 2 weeks. But isolongifolenone is considered safer, and Wang is testing higher rates in hopes of gettting a full day’s protection.

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Carbon Dioxide Gas Combats Bed Bugs

July 24, 2012

CARBON DIOXIDE GAS, an essential nutrient for photosynthesis and the human and animal food chain consuming green plants, can also play a key role in bed bug control. As an attractant, carbon dioxide (CO2) is useful for monitoring and trapping bed bugs and other vampire-like blood-suckers attracted to the gas, including ticks, mosquitoes, and assorted biting flies. Carbon dioxide gas, which has been used to fumigate everything from stored grain and food products to freight containers, museum collections, and hotel and motel rooms, can also be used to fumigate clothing, furnishings, books, electronics, and other bed bug-infested items.

Carbon, carbon dioxide, and the carbon cycle are integral to our very existence on planet Earth. “The carbon of the Earth comes in several forms,” writes University of Cambridge chemist John Emsley in his fascinating Oxford University Press book, Nature’s Building Blocks (An A-Z Guide to the Elements). “Most of what we eat –carbohydrates, fats, proteins and fibre – is made up of compounds of carbon…most ingested carbon compounds are oxidized to release the energy they contain, and then we breathe out the carbon as carbon dioxide. This joins the other carbon dioxide in the atmosphere, from where it will again be extracted by plants and become part of the carbon cycle of nature…The cycle rules the tempo of life on Earth and turns over 200 billion tonnes of carbon each year…In this way carbon is passed up the various food chains, with each recipient releasing some as carbon dioxide, until most carbon is back where it started.”

Does this mean that using carbon dioxide for bed bug control is environmentally acceptable, since it is kind of a “miracle of life” gas behind photosynthesis and plant life? Or is carbon dioxide really more the evil greenhouse or global-warming gas causing global climatic havoc and deserving of punishment via carbon taxes and elimination from the atmosphere via geological carbon sequestration (storage) schemes? Perhaps we should offset carbon dioxide releases for bed bug pest control with offsetting carbon dioxide injections into greenhouses, where elevated CO2 levels increase yields of greenhouse roses, tomatoes, cucumbers, peppers and other crops.

“Carbon is probably the most important element from an environmental point of view,” writes Emsley in Nature’s Building Blocks. “The Earth’s early atmosphere may have contained a lot of carbon dioxide and methane, but once life evolved that began to change. Today, there is very little of these gases and a lot of oxygen instead, thanks chiefly to the action of plants which convert carbon dioxide and water into carbohydrate and oxygen by photosynthesis. The Earth’s atmosphere contains an ever-increasing concentration of carbon dioxide and carbon monoxide, from fossil fuel burning, and of methane, from paddy fields and cows. Human contributions to these sources are still minor compared with natural sources: most carbon dioxide comes from plants, microbes and animals, while methane is given off by swamps, marshes and termite mounds.”

Obviously best to avoid bed bug infestations, and not have to think about remedies like carbon dioxide trapping or fumigations. Italian chemist Primo Levi makes the most persuasive literary argument: “Carbon dioxide, that is, the aerial form of carbon…this gas which constitutes the raw material of life, the permanent store upon which all that grows draws, and the ultimate destiny of all flesh, is not one of the principal components of air but rather a ridiculous remnant, an ‘impurity,’ thirty times less abundant than argon, which nobody even notices. The air contains 0.03 percent; if Italy was air, the only Italians fit to build life would be, for example, the 15,000 inhabitants of Milazzo in the province of Messina. This, on the human scale, is ironic acrobatics, a juggler’s trick, an incomprehensible display of omnipotence-arrogance, since from this ever renewed impurity of the air we come, we animals and we plants, and we the human species, with our four billion discordant opinions, our millenniums of history…”

Bed bugs concern themselves little with environmental correctness, and just tune into characteristics like the heat and carbon dioxide released by metabolizing warm-blooded meal hosts like humans, poultry, rodents, rabbits, etc. A flush from a CO2 cartridge is enough to flush bed bugs from their harborages or hiding places onto a bed in search of a meal. But more naturally, bed bugs follow CO2 gradients to locate live hosts for their blood meals.

“Carbon dioxide has been shown by several researchers to be the most effective attractant for bed bugs,” University of Florida-Gainesville entomologist Philip Koehler told a recent Entomological Society of America (ESA) annual meeting. Humans produce about 700 mg (0.02 oz) of CO2 per minute. “Thus, detectors with very slow CO2 releases cannot compete with human hosts,” said Koehler. “A rapid CO2 release is a better mimic to the human breathing pattern. Detectors with fast CO2 release captured about 4x more bed bugs than detectors with slow release.”

Trapping or monitoring bed bugs with CO2 is complicated by the fact that at different times in the life cycle bed bugs seek out hosts (releasing CO2) for blood meals when hungry; and then when well-fed, instead of CO2 bed bugs seek shelter in groups or cracks and crevices. So although CO2 is the better lure for hungry bed bugs, bed bugs that have fed have different needs and respond to different lures.

A commercial product, FMC’s Verifi(TM) trap, is a dual-action detector combining “fast CO2 generation with liquid kairomone and pheromone lures to attract both host-seeking bed bugs and aggregation-seeking bed bugs,” Koehler told the ESA. Carbon dioxide and the kairomone lure blood-seeking bed bugs into a pitfall part of the trap from which there is no escape. A pheromone lures harborage- or aggregation-seeking bed bugs seeking shelter in cracks and crevices into another part of the trap.

“An inexpensive detector that can be left in place and routinely serviced is needed to aid pest management professionals,” Ohio State University’s Susan Jones told the ESA. “Rutger’s do-it-yourself dry ice (frozen CO2) traps are a cheap and effective method for overnight surveys of potentially infested habitations.” An experiment in a 13-story high-rise apartment building in Columbus, Ohio compared (see You Tube video) 3 Verifi(TM) bed bug detectors per room with 1 CO2-generating dry ice trap per room and canine (dog) detection teams (2 dogs/room; same handler).

Verifi(TM) traps detected bed bugs in 11 of 17 infested rooms in the first 24 hours; and in 14 of 17 infested rooms within a week. Dry ice traps had similar efficacy. Dogs detected bed bugs in 19 rooms, including 3 rooms where neither visual inspections nor dry ice or Verifi(TM) traps detected anything. But the dogs were also not perfect, as each dog also missed 1 room rated positive for bed bugs. So the quest to capture bed bugs with carbon dioxide and other lures goes on.

Human ingenuity seems almost unlimited when it comes to traps. Carbon dioxide, heat and other attractants are all being tested with traps as varied as Susan McKnight Inc.’s Climbup bed bug trap and pitfall traps made from inverted dog bowls painted black on the outside. Rutgers’ Narinderpal Singh tested CO2, heat, and lures such as nonanol, octanol, 1-octen-3-ol, coriander, and spearmint with inverted dog bowl pitfall traps. CO2 had an additive effect with multiple-component lures in inverted dog bowl traps, and may be developed into an inexpensive monitoring system for detecting low levels of bed bugs. Trials with baited traps are continuing.

Both carbon dioxide and ozone show fumigant potential against bed bugs. Purdue University’s Kurt Saltzmann told the ESA of “Two devices capable of delivering ozone to laboratory fumigation chambers.” One device delivered a short exposure to high ozone levels, and the other long exposure to low ozone levels. “Preliminary experiments showed that adult male bed bugs were susceptible to relatively short periods of ozone exposure when high concentrations of ozone were used,” said Saltzmann. “100% mortality was achieved when bed bugs were exposed to 1800 ppm ozone for 150 minutes.” Low ozone fumigation is also being tested with 1-2% hydrogen peroxide for up to 72 hours.

Carbon dioxide (CO2) is used by libraries, museums, and others as an insect-killing fumigant. Indeed, dry ice (frozen CO2) to release CO2 gas is cheaper than washing and drying fabrics to kill bed bugs, Rutgers University’s Changlu Wang told the ESA. At an 80% concentration, CO2 kills all bed bug eggs in 24 hours (eggs are the toughest bed bug life stage to kill). A 50% CO2 concentration for 8 hours is sufficient to kill bed bug nymphs (immatures) and adults.

Wang’s CO2 fumigations involved filling Husky garbage bags 90% full of items such as mattress covers and fabrics, leaving little room for air. Then the bags were sealed with dry ice inside for several hours. Books, electronics, toys and other items damaged by heat treatments might benefit from the low temperatures created by dry ice treatments. However, for safety reasons Wang recommends wearing gloves and turning on fans for ventilation when opening many bags filled with carbon dioxide gas (fumigant).


Hotels & Rooms Too Hot for Bed Bugs

April 7, 2011

HOT HOTEL ROOMS and hot dorm rooms are part of the bedbug buzz at the Entomological Society of America (ESA) annual meetings. There are even indications that hot air remedies can work well in combination with other bedbug control methods, including pesticides and dogs that sniff out bedbugs.

More companies are getting into commercial heat treatments for bed bugs. It seems a matter of practical application of the scientific data that heat can kill bedbugs, if you can figure out how to get the heat to where the bedbugs are hiding. Check out You Tube to see some companies in action using heat treatments against bedbugs, and read the comments (not everyone is convinced).

It is called integrated pest management (IPM) when you combine methods. KTLA News in Los Angeles has an amusing You Tube video combining dogs to sniff out bedbug pheromones with a propane heating device with a fan to cook cockroaches and bedbugs hiding out in rooms. Bed Bug Central TV (BBCTV) is also turning up the heat on bedbugs on You Tube. ThermaPureHeat has one of the best videos, with a Bakersfield heat fumigation job followed by a jazzy closing chorus of “don’t let the bed bugs bite ya.”

Roberto Pereira has been working on hot air fumigation treatments to kill bedbugs in University of Florida dorm rooms during the summer breaks between school years. Heat treatments have a long history of use in entomology (e.g. termites, stored product pests), but it takes some air circulation knowledge and skill.

Pereira and the University of Florida have come up with a short video of their heat chamber idea to disinfest furnishings: “Basically, we put all the furniture of the room at the center of the room, we create an oven around it by using insulation boards, and then inside the box, we put two heaters and fans so that the air is heated and it’s circulated within the box.”

Pereira also tested the combination of hot air fumigation plus “pest strips,” like what you find for sale in supermarkets and hardware stores, for use in EMPTY dorm rooms after all the students have gone home for the summer. You definitely do not want to breathe in the dichlorvos fumes from “DDVP Pest Strips,” particularly when the heat speeds up the chemical release. Though labeled for use at the rate of 1 strip per 900-1,200 cubic feet (25.5-34.0 m3) or no more than 2 strips per room, Pereira cautions that this treatment is for EMPTY rooms in which no one will be living for several weeks.

“DDVP is not something you should be breathing,” said Pereira, who noted that there is a 4-hour per day exposure limit. Indeed, buried in the pest strip label is the following warning: “HOUSEHOLD USES: Use only in Closets, Wardrobes, Cupboards and Storage Spaces. DO NOT USE IN AREAS OF A HOME WHERE PEOPLE WILL BE PRESENT FOR AN EXTENDED PERIOD OF TIME (e.g. Living Room, Family Room).”

Pereira’s work with the easily available pest strips was what is known in science as a “proof of concept” experiment. The idea being that if pest strips worked well with heat, a “softer” chemical, perhaps a botanical or herbal product, could be then be substituted. For scientific experiments, dorm rooms are ideal because they are identical modules. When you start getting into homes with furniture, where every room is slightly different, circulating hot air to kill bedbugs gets trickier.

Box fans placed behind space heaters were used in the Florida dorm room experiments. At 95-97 F (35-36 C), heat killed exposed bed bugs, but bed bugs in hiding (insulated vials) continued living and laying eggs. DDVP pest strips alone, with no heat, took 7 days to kill 100% of bed bugs. With fans circulating heat and pest strip poisons, bed bugs were killed in one day.

Thomas Jarzynka of Massey Services in Orlando, Florida, told the ESA that heat can penetrate walls to kill bedbugs missed by chemical treatments. Two 1,500-watt heaters were inadequate for a hotel room. Jarzynka recommends three 18,000-watt heaters. Besides being energy intensive, temperatures have to be monitored closely to avoid burning furnishings or surfaces. Heat treatments of hotel rooms are started at 7-8 a.m., and temperatures held at 120 F (49 C) for at least 4 hours (sometimes up to 8 hours). Wallboard probes are used to measure temperatures, as it is especially tough to circulate heat to kill bedbugs at carpet level in wall-floor junctions.

Heating a room to kill bedbugs is a bit of an art, combined with some knowledge of engineering and construction materials. Arrangement of room furnishings is critical to heat circulation by fans, said Jarzynka. Fans can be arranged to move hot air along an outer circle, direct heat to a central area, leave cool spots, etc. Rooms can be heated one section at a time, and furnishings can be moved or turned 360 degrees to avoid being burned by heaters.

Bedbugs are tough to get in their hiding places, even with chemicals. So heat treatments, if done right, make good sense. But you need to do your homework, if you want to make life too hot for bedbugs to bite.


Ozone Oxygen (O3) Fumigation for Organics

June 29, 2010

OZONE, A NATURAL OXYGEN (O3; 3 oxygen atoms) molecule that can also be synthesized, is among many other things an alternative to fumigants such as chlorine, methyl bromide, phosphine, and sulfuryl fluoride. Modern day humans have an almost schizophrenic, Jekyll-and-Hyde relationship with ozone, alternately and simultaneously seeking to eliminate and preserve ozone in the environment.

At stratospheric heights 12-15 miles (20-25 km) above the Earth’s surface, in what is called the ozone layer, 90% of the planetary ozone swirls and drifts about in molecular clouds, protectively absorbing mutation-inducing ultraviolet solar radiation wavelengths (also linked to immune disorders, cataracts, skin cancer, crop damage). For that reason an international treaty, the Montreal Protocol, was enacted in the mid-1980s to protect the ozone layer against known and unknown (to be discovered in the future) molecules destructive to ozone. That’s the good Dr Jekyll aspect of ozone (with apologies to Strange Case of Dr Jekyll and Mr Hyde author Robert Louis Stevenson).

Closer to Earth’s surface, where the 10% of planetary ozone not in the upper atmosphere resides, metropolitan areas such as Los Angeles and Phoenix suffer from ozone pollution and come under regulatory fire from the U.S. Environmental Protection Agency (EPA) because what is good 12 miles high is harmful at ground level. In “America’s Most Polluted Cities,” Forbes.com’s (04.28.10) Tim Kiladze calls it “harmful ozone, a ground level gas that contributes to urban smog and inflames the lungs, causing shortness of breath, wheezing and throat irritation.” The American Lung Association State of the Air 2010 report web site formulates EPA ozone and particle pollution data for American cities and counties into searchable form.

So, will ozone gas as an alternative to ozone-destroying fumigants like methyl bromide create more ground level ozone pollution or help replenish and preserve the protective stratospheric ozone layer?

“Chemicals can have their seasons, just like fashions. What one age admires as fine, another will reject as folly, and a good example of this is ozone,” writes John Emsley in his 1998 book, Molecules at an Exhibition. “A century ago ozone was also something to worry about, and for exactly the opposite reason: it was thought there was not enough of it around. Ozone was deemed to be natural, wholesome and invigorating, and the very locations where its levels were highest proved this: up in the mountains and along the coasts…Such was the esteem in which the Victorians held ozone that they had generators pumping it into churches, hospitals, theatres and even their underground railways.”

At the 2009 Entomological Society of America (ESA) annual meeting in Indianapolis, ground-level ozone was back in fashion as an environmentally-friendly fumigant molecule (unstable; decomposes quickly). Methyl bromide (another natural molecule) faces demise as a fumigant under the Montreal Protocol for destroying ozone. And stored grain insect pests are becoming resistant to phosphine. Carbon dioxide, a waste gas exhaled by humans and a feedstock of sorts for green plants, has some fumigant potential but is too slow-acting and unfashionable as a warming greenhouse gas.

Though it is easy to pump ozone through hoses into grain bins, ozone does not penetrate the dense grain well and fumigations can last 3-10 days. Purdue University’s Marissa McDonough noted that the grain is more quickly disinfested of red flour beetles (Tribolium castaneum), maize weevils (Sitophilus zeamais) and other pests by physically moving the grain in layers exposed to ozone sprays in passing.

Potency, ease of use, and low cost make for a good fumigant, said Kansas State University’s Mahbub Hasan, who noted that phosphine, sulfuryl fluoride and ozone are all potential alternatives to methyl bromide fumigation for dry-cured hams attacked by red-legged ham beetles (Necrobia rufipes), ham mites (Tyrophagus putrescentiae), cheese skipper flies (Piophila casei) and carpet beetles (Dermestidae). Carbon dioxide was too slow, said Hasan, taking six days to knock out ham mites. An integrated (IPM) approach combining biological controls, cooling, pheromone traps, ozone and botanical fumigants may ultimately be devised for protecting stored foodstuffs.

However, ozone remains out-of-favor in the plant world. “Tomato plants may be more susceptible to wounding by caterpillar pests in ozone than in ambient air,” Western Illinois University’s Sue Hum-Musser told the ESA meeting in Indianapolis. “Several genes play important roles in plant defenses against the combined stress of ozone and insect herbivory. Increasing ozone levels cause damaging effects on the plant community, and insect pests cost billions of dollars to agriculture.”

Fashion is a fickle thing, and future ozone fashions will likely remain a twenty-first century Jekyll and Hyde muddle.