Cockroaches
Cockroaches in the home environment are a health hazard not only because of the risks posed by cockroach antigens to asthma sufferers, but also because they can carry disease-causing germs and because some of the methods traditionally used to eliminate them cause additional health hazards.
Health Impacts
Common Locations
Testing for Cockroaches
Reducing Exposure
Prevention
Elimination
More Information
Health Impacts
Traditionally, cockroaches were controlled because they are offensive, leave behind an awful smell, and cause gastrointestinal and respiratory illness. However, research shows that cockroach debris (old shells, saliva, body parts, and droppings) triggers asthma attacks in people who are sensitized to cockroach antigen (proteins found in the debris). In homes where several allergens are present, including dust mites, mold, furry pets, tobacco smoke, and certain chemicals, children may experience severe and frequent asthma attacks from high airborne concentrations of these allergens.
Because young children spend more time indoors, allergens found in homes and other buildings pose a significant health risk for asthma sufferers. With asthma rates growing at a startling rate, the hazard posed by the presence of any cockroaches must be addressed.
Common Locations
Any home with food or moisture can have cockroaches. Kitchens and bathrooms typically have the highest number of cockroaches due to the presence of food products and moisture from plumbing fixtures.
Apartment buildings often have the worst infestations. The goal is to keep cockroaches out of the home and to eliminate existing pests. Reaching this goal is not always easy, especially in multi-unit housing that is already infested. For most apartment buildings, the landlord must take a building-wide approach to controlling these pests. Moreover, a coordinated effort by the landlord and all tenants is required to eliminate cockroaches.
Testing for Cockroaches
Generally, determining whether a home has a cockroach problem and the extent of the infestation involves the use of glue traps, which can be purchased at most hardware or grocery stores. The traps are laid out in target areas, where they are left for at least one night. Upon either filling the trap with cockroaches or waiting a predetermined length of time, the number of cockroaches caught on the glue trap is counted to provide an estimate of the extent of the cockroach problem in the home environment.
If an apartment building is to be sampled, it is best to test more than one unit. If only one unit is tested, the landlord may claim that only that unit is infested and put the blame for the problem solely on that tenant. Most housing codes put responsibility for cockroach control on the landlord if two or more units are infested.
Reducing Exposure
Any home can have cockroaches. However, there are steps you can take to prevent cockroaches from becoming a problem in your home; identify the extent of and solutions to any potential cockroach problem; and reduce or eliminate cockroach problems.
Prevention
General maintenance and cleaning are important because they remove the food, water, and shelter on which cockroaches depend, and block the entrances cockroaches use to get into housing. There are many steps tenants, landlords, and homeowners can take individually and jointly to prevent cockroach infestation of the home environment.
- Wipe off counters, tables, and stovetops after all meals, snacks, and food preparations.
- Keep food confined to specific areas of the house and clean any spills immediately.
- Keep all food and garbage in tightly sealed containers, and do not allow trash to accumulate too much.
- Do not leave dirty dishes in the sink, on the counter, or in the dishwasher overnight.
- Fix leaky pipes, faucets, toilets, and other plumbing problems, as well as leaky roofs.
- Use a bathroom fan that vents to the outside after all baths and showers to reduce humidity. Dry any damp areas in the kitchen or bathroom to keep moisture down.
- Remove all piles of boxes, cardboard, newspapers, etc. from both inside and around the home. Cockroaches can both live in and eat these materials.
- Remove other clutter as well to eliminate shelter and hiding places for cockroaches.
- Caulk all cracks and crevices throughout the home around systems such as plumbing, electrical, and gas lines, as well as in places like cupboards and walls.
As an added bonus, integrated pest management techniques that control cockroaches can also help to minimize exposure to other environmental hazards. For example, controlling moisture by fixing leaks and drying up spills can also help prevent exposure to lead and mold. Safe and effective pest management techniques must be utilized, because some chemicals used to treat pests are toxic, may exacerbate asthma symptoms, and are not successful at ridding homes of cockroaches.
Elimination
The ultimate goal is to keep cockroaches out of a home and when necessary, to eliminate those that are there, while keeping residents safe. Reaching this goal can be difficult, especially in multi-unit housing that is heavily infested. For most apartment buildings, the landlord must take a building-wide approach to controlling cockroaches. Normally, it will take a coordinated effort from the landlords and tenants to eliminate cockroaches. Getting their support takes compelling evidence, such as a trap full of cockroaches coupled with a count of the number of cockroaches.
The initial actions residents and landlords can take are regular cleaning and maintenance to remove the food, water, and shelter for the cockroaches. Not only will this help to prevent a cockroach problem in the first place, it is also crucial to controlling an existing infestation and maintaining a cockroach-free environment.
If a cockroach problem requires remedial action, there are numerous paths of control and products available. Once a cockroach problem has been identified, the landlord or homeowner should call an integrated pest management (IPM) professional to conduct a formal inspection. Care should be taken to avoid residential exposure to pesticides, as these chemicals can be a carcinogenic health hazard in the home. Many pesticides can also trigger asthma attacks and cause developmental disabilities.
Pesticide sprays and fogs should not be used to control the problem. Not only will sprays and fogs leave a residue that is hazardous to human health, they also must be applied periodically and are not effective against cockroaches. Baits and boric acid are safer, more preferable forms of treatment that limit the level of human exposure to pesticides. Using IPM practices such as these to control cockroaches are a healthier way to eliminate the problem than spraying pesticides in your home.
Integrated Pest Management (IPM)
- IPM uses a combination of common-sense practices, information on the life cycles of the pests in question and their interaction with the environment, and available pest control methods.
- In general, practicers of IPM use modes of pest control that are less harmful to people and the environment (such as traps) before considering more drastic measures (such as spraying conventional pesticides).
- IPM presents the least possible hazard to people, property, and the environment.
- IPM is effective, economical, and environmentally sensitive.
More Information
Beyond Pesticides - Integrated pest management to control cockroaches
Least Toxic Control of Cockroaches
Good Riddance to Roaches
Canada Mortgage and Housing Corporation - Farewell to Cockroaches Guide
Environmental Health Watch - Cockroach Control Guide
Gumm, Brian, Home Energy, "Integrated Pest Management in the Home," Vol. 21 Iss. 6 pp. 36-39 (Nov-Dec 2004)
US Environmental Protection Agency - Asthma: Cockroaches and Other Pests
Asthma No Attacks Hotline: 1-866-NO-ATTACKS (1-866-662-8822)
Su Familia (Your Family) Helpline: 1-866-SU FAMILIA or 1-866-783-2645
The National Alliance for Hispanic Health sponsors this helpline to offer Hispanic consumers free, reliable, and confidential health information in Spanish and English and help navigate callers through the health system.
Dust Mites
Dust mites are microscopic creatures that belong to the same class (Arachnida) as spiders and ticks (they have eight legs, not six like insects). They feed primarily on dead skin cells regularly shed by humans and animals. Dust mites are found where their main food source accumulates, such as in beds and carpets.
Unlike insects such as cockroaches, mites are not capable of ingesting water; in order to obtain water, they must absorb it from the air. For this reason, they thrive in humid environments, ranging from 55% to 75% relative humidity. Ideal temperatures for dust mites are between 68º and 77º F. The growth of dust mites can vary on a seasonal basis, or from room to room within a house, depending largely on variations in relative humidity, availability of food sources, and temperature. Mites take about one month to develop from an egg into an adult and have an adult life span of about two to four months. A single adult female may lay up to 100 eggs.
Health Impacts
Common Locations
Reducing Exposure
More Information
Health Impacts
Mite waste products contain an allergen (a substance that causes an allergic immune reaction) that, according to the Asthma and Allergy Foundation of America, adversely affects about 20 million Americans. Sensitive individuals become exposed to this allergen when they inhale household dust, which contains dust mites and their waste products. Exposure to dust mites can trigger an attack in an asthmatic who is sensitive to the dust mite allergen. (Other asthmatics may not be affected by dust mites.) For persons allergic to dust mite allergen, exposure can cause allergic rhinitis (hay fever), which is characterized by nasal congestion, itching, and sneezing. In addition, exposure to dust mites may cause children who are predisposed to develop asthma to do so. (This predisposition is not fully understood, but appears to depend upon a combination of hereditary and environmental factors.) For more information on asthma and allergies, see Asthma, Allergies, and Respiratory Illnesses.
Common Locations
Dust mites thrive in places where dead skin cells are most likely to be found: on mattresses, pillows, bedcovers, carpets, upholstered furniture, stuffed toys, clothes, or other fabric items in the home.
Reducing Exposure
While it is impossible to have a dust-free home, it is possible to live in a home that minimizes dust that is carried in from the outside and to avoid conditions that can promote allergens in dust.
Use materials that are easy to clean. This will make it more difficult for dust mites and mold spores to thrive.
- Dust is easily removed from smooth and cleanable surfaces (smooth flooring such as wood, tile, linoleum, and vinyl) through vacuuming and mopping.
- Use a vacuum cleaner with high filtration features (high efficiency or HEPA filter).
- Carpets pose several problems. They are generally more difficult to vacuum effectively than hard surfaces. Also, carpets and the sponge-like pads often installed under carpet can trap moisture once they become wet (due to a plumbing or water leak, flood, or condensation), providing a fertile setting for mold and dust mites.
- Short- and closed-loop-pile carpets (such as commercial grade carpet) are typically easier to clean than loose-pile carpets where dust and dirt falls through to the underlying material.
Clean fabrics and other dust mite havens. The following measures will kill dust mites and reduce allergen levels.
- Wash sheets in soapy water at 130°F every one or two weeks to kill dust mites. Take blankets to the dry cleaner, hang them outdoors once a year, or wash them frequently.
- Cover conventional mattresses and pillows with allergen-impermeable covers or dust mite covers (micro-porous material to prevent infestation).
- Wash soft toys and stuffed animals regularly in hot water, followed by thorough drying. The heat will kill off the mites.
- Shampoo, steam clean, or beat non-washable rugs and carpets once a year. This removes large particles missed by the vacuum cleaner.
Reduce moisture and maintain a low relative humidity in the home. Since dust mites cannot drink water, they need to absorb it from the air, which is why they thrive in humid conditions. Reducing the humidity in your home will make it less hospitable to dust mites, which do not thrive below 60% relative humidity. It may not be feasible to completely eliminate dust mites from homes in moderately humid climates.
One way to help reduce moisture in the home is to run a bathroom and kitchen fan that exhausts to the outside after showering/bathing or cooking.
More Information
HouseDustMite.org
- Helpful animations and answers to frequently asked questions about dust mites
US Environmental Protection Agency - Dust Mites
University of Nebraska Cooperative Extension in Lancaster County, “House Dust Mites.”
P. Vojta, S. Randels, J. Stout, M. Muilenbert, H. Burge, H. Lynn, H. Mitchell, G. O’Connor, and D. Zeldin, Environmental Health Perspectives, “Effects of Physical Interventions on House Dust Mite Allergen Levels in Carpet, Bed, and Upholstery Dust in Low-Income, Urban Homes,” 815-819 (August 2001).
Asthma No Attacks Hotline: 1-866-NO-ATTACKS (1-866-662-8822)
Su Familia (Your Family) Helpline: 1-866-SU FAMILIA or 1-866-783-2645
The National Alliance for Hispanic Health sponsors this helpline to offer Hispanic consumers free, reliable, and confidential health information in Spanish and English and help navigate callers through the health system.