Mold Remediation in the Cannabis Industry

During the marijuana growing process, mold can occur at any point. Mold is a major threat to cannabis, and an outbreak can be detrimental to an entire crop and, in turn, profits. Mold prevention and remediation are practices that are essential to a successful grower. Before plants enter the growing room, it is key that measures are taken to ensure no mold spores are present. This can be done to 100% effectiveness through chlorine dioxide gas decontamination. An entire facility can be sealed and decontaminated using gaseous CD to completely sterilize the space, eliminating any pre-existing organisms and their spores. A quick, chemical-free, highly effective room disinfection alternative can be implemented through ultraviolet light. Unlike a gas that can result in complete distribution of the decontaminating agent, UV-C will only kill where light is emitted onto. However, for an affordable and simple method, UV-C is the optimal solution.

The Torch™ is an easily transportable, powerful disinfection system that can be positioned in the room to achieve a 99% kill level on any surface, including plants, the light is emitted onto in mere minutes. Seeds and buds can be placed in an ultraviolet light chamber, such as the Flashbox™ or Flashbox-mini™, to achieve kill on potential spores without causing death to the seed. Seeds can also be placed inside of a Tyvek™ pouch and decontaminated inside a chlorine dioxide gas isolator.

Mold spores are also highly present in the air. To destroy this risk, ultraviolet light air circulation technology can be implemented to eliminate spores. Designed to replace a standard ceiling tile, the Torch Aire-Recessed™ installs easily to help reduce airborne pathogens. Air is drawn into the fixture through the louvered filter panels and disinfected within the center chamber. This design prevents UV-C exposure to those in the room by restricting light from passing into the occupied room, making it safe for people to be in the room at all times.

View all of our contamination control products to see what might fit your facility's needs best. 

Case Study: Successful Decontamination of an Aseptic Fill Isolator Using Chlorine Dioxide Gas

Isolators are gas-tight enclosures typically used in either animal isolation or pharmaceutical production applications. The isolator acts as a small clean room to protect what is contained within it from any type of contaminant that exists in the normal environment. In any scenario of isolator use, the cleaning of the inside is periodically needed and can often present a challenge to the user and facility. In many applications, the isolator will be sprayed with a variety of cleaning compounds and then wiped down. While the spray and wipe is better than not cleaning at all, it will rarely result in creating a sterile environment within the isolator. The best method for creating a sterile isolator before or after use is by exposing it to a true gas, such as a chlorine dioxide (CD).

One pharmaceutical company tested a chlorine dioxide gas generator for its sporicidal activity on a prototype La Calhene aseptic fill isolator equipped with two half-suits. Twenty biological indicators were used as the microbial challenge for each test.  They were placed throughout the isolator on representative surfaces such as the exhaust vent, HEPA fan grill, and accumulator.  The biological indicators were either used in their original glassine envelopes or removed from the glassine envelope and transferred into Tyvek/film pouches. The variables of humidification time, CD concentration and CD exposure time were manipulated. Charging time to an exposure concentration of 5mg/L took approximately 9 minutes. Aeration time to safe exposure levels of 0.1ppm took less than an hour. Several exposure cycles were shown to be successful using biological indicator spore strips each having a population of 106 spores. Additionally, chlorine dioxide gas penetrated into dead-leg areas and hard to reach areas of the isolator, such as deep vents, half-suit armpits and beneath other structures. Chlorine dioxide has proven itself to be a practical and effective method for disinfecting isolators as demonstrated by the high-level spore reduction.

To read this company’s isolator decontamination study in full, click here. For more about this specific application, click here.

The Influx of Influenza

It is widely known that the flu is a threat to everyone’s health.  The CDC estimates that the flu has resulted in between 9.3 million and 49 million illnesses each year in the United States since 2010¹.  We often times hear that the flu vaccine is the best approach to avoid contracting the illness, however it is not always effective.  There are two main explanations as to why the vaccine may not prevent contracting the flu.  One is the overall attributes of the person being vaccinated, such as their age and health.  The other is the correlation between the flu viruses currently in the environment and the flu vaccine currently designed to protect our population. 

Another way to eliminate the harmful influenza virus is by eliminating it from the environment through ultraviolet light (UV-C) disinfection.  With the proper dosage, UV-C kills any organism that the light shines upon.  There are even UV-C devices designed to disinfect airborne contaminants such as the influenza virus.  The Torch Aire- Recessed™ replaces a 2’x4’ ceiling tile and has the ability to disinfect up to 12,600 cubic feet per hour.  Air is pulled into the unit and passed over enclosed UV-C lamps to kill any harmful organism in seconds.  The air is then sent through a filter, trapping any large particulates before they have the chance to reenter the space.  It is perfect for any healthcare setting thanks to its ability to continuously run while the room is occupied, as well as its ease of placement and its rapid and effective performance.

Learn more about this unit, and other UV-C disinfection devices that can fit any application you may have, by contacting us here or by visiting us at APIC June 12-14 in Philadelphia at booth 1239!   

1. www.cdc.gov

The Myths and Misconceptions of Chlorine Dioxide Gas

Chlorine dioxide gas has been recognized as a disinfectant since the early 1900's, and it has been approved by the US Environmental Protection Agency (EPA) and the US Food and Drug Administration (FDA) for many applications in a variety of industries. It has been demonstrated effective as a broad spectrum, anti-inflammatory, bactericidal, fungicidal, and virucidal agent, as well as a deodorizer. Even though chlorine dioxide has been around for over a century, there is still a surprising amount of inaccurate information and misconceptions. We would like to take the opportunity to address some of those misrepresentations.

CHEMICAL PROPERTIES

Although chlorine dioxide has "chlorine" in its name, its chemistry is radically different from that of chlorine. When reacting with other substances, it is weaker and more selective, allowing it to be a more efficient and effective sterilizer. For example, it does not react with ammonia or most organic compounds. Most importantly, chlorine dioxide oxidizes products rather than chlorinating them, eliminating the formation of trihalomethanes (THMs), haloacetic acids (HAAs) and other environmentally undesirable chlorinated organic compounds.

SAFETY

The very reason decontaminating agents are used is for the purpose of killing organisms. As such, no agent can truly claim to be safe. However, chlorine dioxide gas is the safest fumigant available, due to its physical attributes and process advantages. Chlorine dioxide is not classified as a carcinogen by any health agency. Chlorine dioxide does have an odor similar to chlorine, which is beneficial because chlorine is such a recognizable smell. The odor detection level is very similar to the OSHA 8-hr safety level of .1 ppm allowing you to detect any gas leakage quickly. Cycle times are shorter with CD gas due to its faster aeration time to safe levels. This means that a potentially unsafe condition exists for a far shorter time when using CD for room decontamination.

WATER SOLUBILITY

Unlike many decontaminating agents, chlorine dioxide has the unique ability to retain its sterilization capacity in water. Chlorine reacts with water to form hydrochloric acid, but chlorine dioxide does not, maintaining a neutral pH in water. Gaseous CD is the only decontaminating fumigant that penetrates water, decontaminating both the water and the surface beneath.

MATERIAL COMPATIBILITY

The leading liquid chlorine dioxide solutions are produced through the mixing of an acid and a base. It is this acid which makes the liquid chlorine dioxide solution highly corrosive. ClorDiSys, however, does not produce chlorine dioxide gas in this same way. The method of generation ClorDiSys uses is a completely dry process where a 2% chlorine, 98% nitrogen gas flows through a matrix of sodium chlorite to produce producing 100% pure chlorine dioxide gas. The chlorine dioxide gas generated through the ClorDiSys process has an oxidation potential that is 1.5 times less that of vapor-phase hydrogen peroxide (VPHP), making it technically less corrosive. Because ours is a pure and dry process, our chlorine dioxide gas doesn’t leave a residue and does not require additional cleanup.

MORE COMMONLY USED THAN YOU THINK

Chlorine dioxide is widely used as an antimicrobial and as an oxidizing agent in drinking water, poultry process water, swimming pools, and mouthwash preparations. It is used to sanitize fruit and vegetables and also equipment for food and beverage processing. It is also employed in life science research laboratories, pharmaceutical facilities, and the healthcare industry to decontaminate rooms, passthroughs, isolators, and ductwork as well as product and component sterilization. It is also extensively used to bleach, deodorize, and detoxify a wide variety of materials, including cellulose, paper-pulp, flour, leather, fats and oils, and textiles. Approximately 4 to 5 million pounds are used daily.

Contract Sterilization

ClorDiSys Solutions offers Contract Sterilization Services where we can decontaminate your items, equipment, supplies, and products at our facility and then ship them back to you or onward to a third party. ClorDiSys utilizes chlorine dioxide gas, a US EPA registered sterilant capable of killing all viruses, bacteria, fungi, and spores. Chlorine dioxide gas is also effective against beta lactams such as Penicillins, Cephalosporins, and Carbapenums as well as amplicons and pinworm eggs. Customers can choose to single or double wrap items in Tyvek and may include biological indicators as well. Turnaround time is traditionally 24 hours, with items typically being shipped back the day after they arrive. In some cases, turnaround time can be hours, with the items arriving, being treated, and shipped on the same day. Upon completion, you will be issued a Contract Decontamination Certification Sheet describing the process and showing the sterilization cycle data.

APPLICATIONS 

• Sterilization for Non-Sterile Facilities

• Medical Devices, Instruments, HEPA and other Sterilizing Filters
• Equipment, Components, and Items entering a Clean Facility
• Tools, Computers, Printers, Keyboards, RFID Tags, Monitoring Instruments, Microscopes, Animal Cages, Shoes, and Safety Glasses
• Decontamination of Contaminated Components
• Returns from user sites, mold issues, pinworm eggs, amplicons, and beta lactams

View our sample submittal form and call the office at (908) 236-4100 with any questions.

Chlorine Dioxide: What Does it Kill?

ClorDiSys' chlorine dioxide (CD) gas is registered with the United States Environmental Protection Agency as a sterilizer (EPA Reg#: 80802-1). The US EPA defines a sterilizer as able "to destroy or eliminate all forms of microbial life including fungi, viruses, and all forms of bacteria and their spores," meaning ClorDiSys' chlorine dioxide gas will inactivate any form of antimicrobial life including spores. Spores are among the hardest organisms to kill and for this reason sterilizing agents are considered the most rigorous decontaminating agents. The difference between spore and bacterial inactivation is the same as the difference between sterilization and disinfection. CD gas is also proven effective against beta-lactams, pinworm eggs, and amplicons. Testing has been done using chlorine dioxide on a multitude of specific organism types. A table with some of the more commonly seen organisms that chlorine dioxide has been proven to eliminate can be viewed here. As testing is constantly ongoing, this is not to be thought of as a complete list of organisms in which chlorine dioxide gas is effective against. To date, no organism tested against CD gas has proved resistant.

Chlorine Dioxide & Food Contact Surfaces

As a residue free process, chlorine dioxide gas is safe for use on food contact surfaces. It is even on the National Organic Program's List of Approved and Prohibited Substances as an approved substance for use on organic foods. ClorDiSys has also been approved by the U.S. Food and Drug Administration’s (FDA) for antimicrobial fruit and vegetable rinses in both the gaseous and liquid states with more approvals in the works now.

Chlorine dioxide’s use is allowed under FDA jurisdiction as given in the following regulations: 

• 21 CFR PART 173 -- SECONDARY DIRECT FOOD ADDITIVES PERMITTED IN FOOD FOR HUMAN CONSUMPTION
• 21 CFR PART 178 -- INDIRECT FOOD ADDITIVES: ADJUVANTS, PRODUCTION AIDS, AND SANITIZERS
• 21 CFR PART 137 -- CEREAL FLOURS AND RELATED PRODUCTS 
• GRAS Notice 062, GRAS Notice 161

The above incorporate a variety of industry applications including chlorine dioxide’s use as an antimicrobial agent in water used in both poultry processing and for washing fruits and vegetables. It is also allowed as a sanitizing solution on food-processing equipment and utensils, to bleach whole wheat flour, and can be used in packaging materials for fresh fruits, vegetables, meats, poultry and seafood. 

Food Contact Notices (FCN) are required for any new food contact substance and uses which do not fall under the scope of the regulations above. A FCN is effective for the manufacturer, the Food Contact Substance (FCS), and the conditions of use identified in the notification and not effective for a similar or identical substance produced or prepared by another manufacturer. ClorDiSys has the following food contact notices in place: 

• FCN 1665 – Chlorine dioxide as an antimicrobial agent used to fumigate fruits and vegetables, including raw agricultural commodities. 
• FCN 1634 – Chlorine dioxide as an antimicrobial agent in water used in poultry processing and to wash fruits and vegetables, including raw agricultural commodities (RAC). 
• FCN 1421 – Chlorine dioxide as an antimicrobial agent in air to treat fruits and vegetables. 
• FCN 1400 – Chlorine dioxide as an antimicrobial agent in water used in poultry processing and to wash fruits and vegetables that are not raw agricultural commodities.

Click here to view the Food Contact Notices in their entirety, and be sure to stop by Booth #1635 at next week’s Petfood Forum and Booth #433 at next month’s Food Safety Summit.

Fogging with Liquid Chlorine Dioxide

If your facility does not necessarily require a 6-log (99.9999%) sterilization level decontamination, ClorDiSys offers alternative options to our chlorine dioxide gas services including chlorine dioxide fogging. The term fogging is the method of decontamination when a liquid is applied in a mist onto a room’s surfaces. Compared to gaseous chlorine dioxide, which spreads throughout an entire facility and penetrates into the smallest cracks, fogging has some limitations.  Liquid fogging has many factors that reduce the ability of this agent to reach all the required areas for the required amount of time in order to achieve a successful decontamination cycle.  Liquids have difficulty penetrating into crevices as they cannot overcome the surface tension.   

When providing disinfection fogging services, ClorDiSys sprays surfaces with liquid chlorine dioxide applied at concentrations capable of eliminating viruses, bacteria, fungi and spores. Handheld foggers are used such that a trained technician is able to reach more surfaces than a stationary fogger by opening drawers, cabinets and enclosures, as well as changing the angle of application in order to minimize shadow areas which are not being contacted. During application, PPE such as a full-face respirator or PAPR is required for all people in the room. Safe concentrations should be verified prior to re-entry without PPE. In most cases, only minutes are required to get below 0.1 ppm prior to re-entry.

Fogging with a liquid chlorine dioxide provides a more economical disinfection method compared to gaseous decontamination, offering a value proposition for less critical contamination control applications.  Interested in learning more about fogging with liquid chlorine dioxide? Email us with any questions or potential projects.

Sealing Up Spaces for Decontamination

Properly sealing a space prior to decontamination is important no matter what method is being used, as they all include some level of risk.  While sealing a space is not a highly challenging process, it does involve both a keen eye and attention to detail.  Typically, the materials used to seal a space consist of duct tape and plastic, occasionally caulk.  The general guideline to sealing a space involves the following:

Seal around any penetrations into the space

This step includes checking to see if any pipes, electrical conduit, conveyors, ductwork, or other items go through the wall/floor/ceiling.  Sometimes these penetrations are sealed, using caulk, gaskets or other means.  When they are not sealed and there is a gap for air to travel into/out of the space, additional sealing is necessary in order to contain the decontaminating agent.  If permanent sealing is appropriate, the gaps can be caulked in place.  For circumstances where permanent sealing is not allowed, duct tape is the primary sealing tool.

Sealing off the HVAC system

In order to provide the decontaminating agent the contact time necessary to achieve the level of kill desired, the space must be isolated from an active HVAC.  Depending upon how the HVAC system interacts with the space and surrounding areas, the supply and exhaust can either be sealed off at the room level or at the roof level.

Sealing doors

Finally, once the penetrations are sealed and the space is isolated from the HVAC, the doors are all that is left to be sealed.  Once again, simply using duct tape to seal around the door is sufficient to properly seal off the area being decontaminated.

Ultraviolet Light Disinfection at Hospitals

Healthcare-associated infections (HAIs) can happen in any health care facility, including hospitals, ambulatory surgical centers, and long-term care facilities.  HAIs have increased 36% over the past two decades. Patients come in contact with many items and surfaces within a hospital. Surfaces such as walls, curtains, remotes, clothing, and handrails are all potential transfer sites of infection. 41% of patient rooms had at least one surface contaminated with MRSA and/or C. difficile.1 The air is another carrier for harmful organisms, leaving the setting as a whole to be potentially very dangerous.

ClorDiSys is proud to offer a complete line of ultraviolet light disinfection products and services to enhance your healthcare facility’s infection prevention program. In the waiting rooms, operating rooms, and patient rooms, the Torch Aire-Recessed allows for continuous disinfection of the flow of air by simply replacing a ceiling tile. The Torch Aire-Recessed can disinfect all the air in a 2,100 ft3 room once every ten minutes.  Any air flowing through is being treated by the concealed UV-C bulbs that kill any pathogen that enter.  The device is quiet, effective, and since the bulbs are hidden from view, can operate even in the presence of patients and staff.

Room surfaces can be disinfected by a variety of UV disinfection systems, including the Torch and Torch+. The Torch is an inexpensive, easily transportable, powerful disinfection system used to provide a rapid and highly effective method to disinfect surfaces and common touch points to reduce the transfer of dangerous organisms. Each Torch tower produces an efficient UV-C output of 12 mJ/minute (200 μw/cm2) to get a calculated 99% reduction of MRSA in 1 minute and Clostridium difficile spores in 5 minutes. The Torch system is designed to be so economical that multiple units are affordable enough to place into a room at the same time to eliminate shadow areas and maximize coverage. For areas needing special attention, the Torch-Flex and Torch Double-Flex are capable of applying UV disinfection within tight spaces and focused areas. If a permanent option is desired, the Flashbar can be installed in the room to provide an even simpler UV system for routine disinfection. By adjusting the quantity and placement of Flashbar units in a room, decontamination can match workflow patterns involved in the facility’s layout.

Make sure your patients leave healthy and stay healthy. Learn more on April 16 at our Ultraviolet Light 101 webinar or visit Booth #1848 at next week’s AORN Global Surgical Conference & Expo.


1.           Faires et al. The Identification and Epidemiology of Methicillin-resistant Staphylococcus aureus and Clostridium difficile in Patient Rooms and the Ward Environment. BMC Infectious Diseases 2013.

Case Studies: Protein Powder Facilities

Chlorine dioxide gas (CD) is the most effective method of decontamination available. It has been used in the food industry for many years for the decontamination of facilities, tanks, rooms, laboratories, piping systems, duct work, spiral freezers, cargo trailers, tented pieces of equipment, and so much more. Below are a couple examples of projects ClorDiSys completed in protein powder facilities.

Protein Powder Refining and Packaging Facility

This 300,000 cubic feet facility consisted of a small packaging room, a mixing room, and a dryer room. The dryer room was 70 feet in height and consisted of various processing equipment with access platforms. Even after thorough cleaning and liquid decontamination, a persistent salmonella problem could not be eradicated. ClorDiSys was able to fumigate the facility utilizing gaseous chlorine dioxide and eliminate the organisms while providing sporicidal kill of Biological Indicators (BI) placed throughout the facility.

Protein Powder Grinding, Drying, and Packaging Facility

This seven room, 200,000 cubic feet facility consisted of packaging rooms, grinding room, mixing room, and a dryer room. The rooms consisted of various processing equipment. There was also an adjacent control room and office area that were also decontaminated to ensure a thorough treatment. ClorDiSys was able to fumigate the facility utilizing gaseous chlorine dioxide and eliminate the organisms while providing sporicidal kill of Biological Indicators (BI) placed throughout the facility.

The decontamination cycle employed by ClorDiSys involves many checks and safety factors to ensure that a thorough level of kill took place. Biological Indicators, also known as BIs or spore strips, are used as a test of the process efficacy.  The BIs used by ClorDiSys consist of a paper substrate impregnated with more than a million bacterial spores wrapped within Tyvek, because this particular organism is known to be of high resistance.  BIs are placed within the area being decontaminated, usually in hard-to-reach areas or hot spots, to confirm the decontamination’s success. 

You can read more case studies from a variety of industries in our Decontamination Services brochure.

Lyophilizer Sterilization

Lyophilizer and freeze dryer are synonymous names for the same equipment. A lyophilizer (lyo) executes a water removal process typically used to preserve perishable materials, to extend shelf life or make the material more convenient for transport. It is usually decontaminated on a periodic basis and after each production batch. The standard process is to decontaminate by using steam to raise the temperature and hold it there until 6-log kill is attained. After the proper sterilization time is reached, the lyophilizer is then left to cool before product is brought in for another cycle. Because of the large thermal mass, this can take many hours. Lyophilizers also need to pull deep vacuums to perform the drying function. Heating and cooling with steam causes thermal expansion and contraction which compromises the tight tolerances required to keep the lyo sealed enough to reach deep vacuum levels. To mitigate these concerns and provide a faster sterilization cycle, chlorine dioxide gas can be used to decontaminate the components.

• Quicker cycles with Chlorine Dioxide Gas than Steam or Vapor Phase Hydrogen Peroxide
• 1.5 to 3 hours depending on desired level of kill and sensitivity of components versus 24 hours for steam or 8 to 12 hours for VPHP.

• Less stress on the lyophilizer with Chlorine Dioxide Gas than Steam 
• No thermal stresses with CD gas as there are with steam, because there are no heating and cooling requirements.

• No cycle development required for Chlorine Dioxide Gas
• CD: 1 mg/liter for 2 hours or 5 mg/liter for 30 minutes of exposure. 
• VPHP: Cycle parameters must be developed for every specific application. If ambient temperatures change, the cycle parameters most likely need to be changed.

To learn more, read our Application Note about this specific use.

Confused Flour Beetle Fumigation

The confused flour beetle is perhaps the most frequently intercepted pest of stored products. Adults and larvae feed on all cereal products, groundnuts, cacao, spices, dried figs and dates, palm kernels, various nuts, oil seeds, and cotton seed. Adults live for one to two years, are capable of flight in warmer conditions, and have been known to produce quinones, which at high population densities tend to trigger dispersion. Because they are such a common concern in flour mills and food processing plants with limited control options, experiments were conducted exposing confused flour beetles to gaseous chlorine dioxide.

The confused flour beetles were exposed to chlorine dioxide at different concentrations and at different lengths to see the effect of the gas on the survivability of the beetles. They were monitored for nine to ten days after exposure. While chlorine dioxide gas is not approved for pest fumigation, preliminary studies indicate that a dosage of 3000 ppm-hours is effective at eliminating all confused flour beetles upon completion.

Learn more about the efficacy and food industry applications at an upcoming workshop or visit us at booth #433 at the Food Safety Summit in May.

Comparison of Sterilization Technologies on Electronics

Although there is considerable literature about sterilization methods, there is little written about the impact of sterilization on electronics. Thanks to the advances in semiconductor and packaging technologies, integrated circuits (ICs) are found in a widening selection of equipment including medical devices. For these devices’ applications, they must remain free from harmful contaminants such as fungi, bacteria, viruses, and spores. Therefore, Maxim Integrated Products, Inc performed a study in June 2010 comparing the biocidal efficacy and material compatibility of steam, Ethylene (EtO), Gaseous Chlorine Dioxide (CD), Vapor Phase Hydrogen Peroxide (VPHP), Hydrogen Peroxide Plasma, Gamma radiation, and Electron Beam sterilization suitability for objects containing batteries or electronics.

The complete application note can be read here, but Table 1 summarizes the methods discussed and their compatibility to embedded electronics. Chlorine dioxide has no known adverse effects on electronic components and is, therefore, the best overall choice for compatibility. EtO and VPHP are noted as excellent choices for electronic medical devices that do not include batteries. Other methods might require electronics to be modified specifically for exposure.

ClorDiSys had no involvement with any testing or research in the development of Maxim’s Application Note.

Ultraviolet Light and the Human Bed Bug

The dramatic resurgence of bed bugs in the United States poses significant problems for individuals, public health officials, and the pest control industry. Bed bugs are responsible for a variety of health concerns, causing the CDC to recently release a joint statement with the EPA declaring bed bugs a significant public health problem. Unfortunately, bed bugs are resilient and difficult to remove due to their cryptic behavior and general physiology.  They are active nocturnally when hosts are sleeping and unaware, and their flattened bodies allow them to squeeze into cracks and crevices, making removal by physical or chemical control methods difficult.

No individual control measure, chemical or otherwise, has proven to be one hundred percent effective in the removal of bed bugs from domestic structures. Eradicating bed bugs from a premise is extremely challenging. Over-reliance on pesticides, such as pyrethroids, has been linked to increased resistance in bed bug populations. Alternative methods of control are needed to aid in a broader removal strategy. Ultraviolet (UV) light is known to damage DNA by altering the nuclei of the cells due to photolytic processes; however, its various effects on arthropods have not been well documented. A 2013 Ohio State University study examined the impact of ultraviolet light on bed bug survival and behavior, and is a first step in determining the potential of UV as a control measure.

The study exposed the two developmental stages of Cimex lectularius, the egg and the first nymphal instar, to ultraviolet light for periods of 1, 2, 5, or 10 seconds at a distance of 4 cm.  A dose response curve was created by calculating mortality following an interval of 2 weeks. Behavioral observations were also conducted to assess the effects of UV exposure on the host seeking abilities of first instar nymphs.  Egg stage mortality was significantly higher in groups exposed to 2, 5, or 10 sec of UV light, with almost no subjects surviving 5 and 10 sec exposures. Mortality in first instar nymphs was somewhat less dramatic, with only the 5 and 10 sec exposures showing significant effects. The 10 sec exposure was the only treatment to cause mortality higher than 50%. It was believed treatment was less effective because these eggs were further along in their development. Behavioral observations supported the hypotheses that host-seeking abilities would be adversely impacted by exposure to UV light.  Both the 5 and 10 sec exposures significantly decreased the host-seeking success rate in first instar nymphs.

This project strongly suggests that ultraviolet light is effective, both in killing bed bugs and impairing their ability to reach a host. While eggs have proven to be most resistant to current control tactics, they are highly vulnerable to UV treatment. Particularly appealing is the fact that UV light provides a dry, chemical-free, and residue-free method of control that, with proper shielding, could be used by consumers without the aid of professionals. This study offers initial proof of concept that it is possible to kill bed bugs using only light.

To read the Ohio State University study in its entirety, click here. If you are attending EMS Today February 20-22, stop by booth #1145 to see some of the ClorDiSys UV-C product line and discuss applications.