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| Essay:Hazards of Insulationhttp://www.hhinst.com/ArtInsulation.html
The Hazards of Insulation Published in East West, September 1989, p. 44. by John Bower (Copyright 1989) All residential insulating materials have some known negative health effects. For most people, the odds are pretty good that the insulation inside the walls of a house will remain there, and will cause no health related problems. The average individual is probably more likely to be affected by sidestream tobacco smoke than by insulation. Unfortunately, there are some people being made ill by insulation. For them, statistics are unimportant. Often, this exposure is the result of remodeling, when new insulation is being installed or existing insulation is disturbed. It is well known that workers in industrial situations, who are exposed to a substance in relatively large quantities for 40 or more hours a week, can be affected to a greater degree than the public at large. The occupational health literature is filled with examples of the dangers of various materials, including insulation. However, there are several segments of the general population that can have a greater susceptibility than these workers, who are usually healthy males in the prime of life. For example, children under age ten do not have fully developed immune systems and elderly people have an immune system that is on the decline. Pregnant women and individuals already ill may also be at greater risk. Insulation installers and do-it-yourself remodelers may be exposed to much higher levels of the product in the air than industrial workers simply because safety precautions are not enforced. There is also a growing segment of the population that is being recognized as being hypersensitive to a variety of air pollutants, including insulation. When considering all of the sub-groups at risk, it soon becomes apparent that we all fit into at least one group sooner or later, for we are all young, old or ill during our lives. There are dozens of different types of insulations in use today. Most have very specialized industrial applications. Of the insulations found in houses, only a few are in common use. Over the years, resourceful individuals have used a wide variety of natural materials to insulate their homes. Such things as moss, feathers, cotton, wool, sawdust, corn cobs, and cork have relatively good insulating properties and as a result they have found their way into more than a few walls and attics. Unfortunately, a material must have more than good insulating ability to be a good insulation. There are many people who are allergic to natural items such as feathers, wool, etc. Also, natural substances make good nesting materials for small animals and insects. They may also provide food for these unwanted residents. Mold growth can also be a problem. Mold can not only be undesirable to allergy sufferers, but it can be detrimental to the health of the house because when wood rots it is being eaten by a fungus. Unless heavily treated with potentially toxic chemicals, these products can also be very flammable. Because of the drawbacks to using natural materials, most insulation producers today rely on man-made concoctions. While these manufactured products are widely used, and believed to be nontoxic, there are some negative health effects that the concerned homeowner should be aware of. The most common way of comparing insulations is by their Rvalue. This refers to a material's resistance to heat flow. Higher R-values mean better resistance to heat flow, hence better insulating ability. Brick has an R-value of 0.11 per inch. Fiberglass insulation has an R-value of 3.17 per inch and extruded polystyrene foam insulation is rated at 5.0 per inch. The R-value can be determined for virtually everything, therefore everything has a certain amount of insulating ability. Brick can certainly be used for this purpose, but fiberglass is much more efficient at doing the job. In fact, it is nearly 29 times as efficient as brick. Materials with high R-valves generally have many very small pockets to trap air. Sawdust is about twice as efficient at insulating as solid wood because it contains more trapped air. Most synthetic foam insulations trap a gas such as Freon, instead of air, in their pores, and as a result, they have higher R-values. Fiberglass is probably the most commonly encountered residential insulation, being used by professional builders and doit-yourselfers alike. Much of its popularity is due to its low material cost: less than a quarter a square foot for 3 1/2" thick insulation. It is made from glass fibers whose diameter is measured in microns. When these fibers are bunched together, they trap a lot of air, giving them good insulating ability. In batt form, it resembles cotton candy. It can be either pink or yellow in color, depending on the manufacturer. Anyone who has worked with this material will attest to the fact that working with it can make your skin itch. This is because the fibers actually make small incisions in the skin. When these fibers are inhaled they can make small cuts in the sinuses or throat, causing respiratory tract irritation. Since all residential batt insulations are coated with a formaldehyde based resin, this resin is in contact with the cut, resulting in further irritation. If very many of these resin coated fibers get into the air and are inhaled, they can cause severe problems. A case in point involves a Rhode Island family: Stan and Eunice Kozikowski and their two children. In 1986 they were having some work done on an air conditioning system in their attic. During the construction process, workmen disturbed the existing fiberglass insulation. When an attic mounted whole house fan was turned on, fiberglass particles were blown throughout the house through an open attic hatch. All four family members suffered eye, ear, skin and respiratory irritation almost immediately. While a thorough cleanup removed most of the particles of insulation, it was impossible to remove it all from such things as carpet, upholstery and clothing. As time passed, a wide variety of symptoms appeared, including: conjunctivitis, dermatitis, intestinal and urilogical disorders, immunological imbalances, chronic chemical sensitization, heart irregularities with accompanying chest pain, acute nervous teeth causing temporal mandibular joint syndrome, acute sinus headaches, migrain headaches, tracheitis, tonsillitis, sinusitis, tachycardia, acute eczema and psoriasis, acute depression, anxiety, and tension. Because of this family's acute exposure, they are now very sensitive to a wide variety of commonly encountered chemicals such as artificial fragrances. This has resulted in severe restrictions and means that their lives will never be the same again. Fiberglass may also be capable of causing lung cancer in the same way that asbestos does. Workers first exposed over 30 years ago to man-made mineral fibers have a slightly higher incidence of lung cancer than the general population. The cancer causing ability seems related to very small particle sizes. The fiber sizes found in most batt insulations are too large to be inhaled deeply into the lungs, however, blow-in fiberglass products may contain particles of similar size to asbestos fibers. These can be inhaled deeply into the lungs where they can lodge, possibly resulting in malignancy. Ken Roberts, an Environmental Services Manager for Manville Corporation, a Denver based fiberglass insulation manufacturer, points out that when asbestos gets into the lungs, it remains unchanged, thus, it can cause damage during the entire life of the victim. On the other hand, he says that fiberglass is eventually dissolved by body fluids, thus it should be of less concern than asbestos. Richard Munson, head of Victims of Fiberglass, an Auburn, California group formed to make the public aware of the dangers of this material, believes that this should cause more concern. Munson claims that when fiberglass dissolves in the lungs, the "decomposition produces silicic acid which is a cytotoxin." Cytotoxins kill living cells. Richard Munson, through Victims of Fiberglass, vigorously attacks fiberglass through bulk mailings, newspaper articles, conferences, and television programs. At the same time, he preaches about the virtues of cellulose insulation, another popular residential product. He says that cellulose is "God's natural insulation. It's like motherhood and apple pie." Munson has a vested interest in condemning fiberglass and promoting cellulose. He also heads a cellulose trade organization called National Consumer Products Marketing Inc., and he is president of a company that manufactures cellulose insulation. While Munson may be on the right track in his fight against fiberglass, he is wrong in comparing cellulose to "motherhood and apple pie." David Buscher, M.D., of Kirkland, Washington, presented several cases studies to a 1982 medical conference describing the negative health effects suffered by some of his patients after their homes were insulated with cellulose. Buscher found high levels of boron compounds in their systems. These are generally in the form of borax and boric acid, chemicals that should not be taken internally. A 1987 case is typical of Buscher's earlier findings. It involved a California woman who remained indoors while her family's home was being insulated with cellulose. As workmen drilled small holes in the exterior and pumped the cellulose into the walls, a small amount found itself into the interior of the home. It drifted in around electrical outlets, window and floor trim, etc. Over the next few months, all of the family reported various symptoms, but the wife's health deteriorated rapidly. She had breathing problems, and a painful rash. Her hair began falling out and her skin turned yellow. Her young son also lost his hair. Their pet German shepherd lost half of one litter and only one puppy in a second litter survived. It wasn't until she realized that she felt better outdoors that she began to suspect the newly installed insulation. Today, after going through a detoxification program and moving out of the house, her health is only marginally better. Cellulose insulation is made from recycled newspapers. The newspaper is ground into a fine, fluffy powder, and it is then treated with a variety of chemicals (primarily boric acid and borax) to render it fire resistant and to discourage vermin from nesting in it. The inks used in printing newspapers are fairly toxic, and while there are some individuals who cannot tolerate the odor of a fresh newspaper, actually inhaling insulation containing this ink can result in a much more severe exposure. Foam insulations are also widely available. This category includes urethane, polystyrene, isocyanurate, urea-formaldehyde, etc. These products usually consist of one or more plastic resins that are puffed into a foam either by a chemical reaction or by a gas. There are a wide variety of these products in board shape. Styrofoam is one brand produced by the Dow Chemical Co. Other products are sold in aerosol cans, and some must be installed by a contractor. Urea-formaldehyde foam was once banned by the Consumer Product Safety Commission, but the ban was later overturned on a technicality. While it is again legal to install it in homes, it will be very difficult to find anyone handling it today because of the serious health problems associated with it. Most of the negative health effects connected with this material were a result of formaldehyde gas being emitted from an incorrectly installed product. If moisture was present in the wall cavity, or the insulation was heated in an attic, even greater quantities of formaldehyde were released. Formaldehyde has many negative health effects including runny nose, difficulty sleeping, fatigue and menstrual disorders. It is also a sensitizer that can trigger sensitivities to other substances in some people. The story of Chuck and Maureen Leyda of Colchester, CT is typical of the many cases of destroyed health attributed to ureaformaldehyde foam insulation. Soon after moving into a recently insulated home, the family experienced skin rashes, colds, bronchitis, coughs, and headaches. Soon, sore throats, stomach cramps, dizziness and extreme weakness were added to their list of complaints. After two years, the entire family of five was on the verge of total physical collapse. At a cost of over $15,000, the Leydas had the insulation removed from their house. This major undertaking meant removal of the plaster walls, removing the insulation, then replastering, repainting, etc. After the nearly two year process, they found that the problem was not over. Now, ten years after they originally moved into the house, Maureen and her daughter remain very sensitive to low doses of a wide variety of cleaning products, cigarette smoke, printing ink, etc. This is because of formaldehyde's ability to sensitize the body to other chemicals. Other foam insulations use a chlorofluorocarbon (CFC) gas, such as Freon, during the foaming process. This gas eventually leaks out of the insulation and many sensitive people report various symptoms related to exposure to it. These types of gases are also implicated in destroying the health of the planet as they build up in the atmosphere, destroying the protective ozone layer. Fortunately, manufacturers are aware of this problem, and they will be using different gases in the future. Dow Chemical plans to use a less stable gas that will break down when exposed to sunlight in the lower levels of the atmosphere, thus helping to preserve the ozone layer. Health effects in factories producing synthetic foam insulations include blurred vision, skin, eye and respiratory tract irritation, asthma, etc. There are many different and varied compounds used in the manufacture of these products. For most of the ingredients the health effects are simply unknown because they have not been studied. Toluene di-isocyanate (TDI) is one of the raw materials used in urethane foam production. It is a sensitizer and has been shown to cause various neurological symptoms. As more studies come to light, undoubtedly more negative health effects will become known. Most foam insulations emit very noxious fumes during a fire. If they are covered by a non-combustible material such as plaster or drywall, they will be fairly well separated from a fire. However, the synthetic carpeting, and modern upholstery materials will give off similar fumes and they will be quickly engulfed in a fire. Vermiculite and perlite insulation are occasionally found in houses. Their use is generally confined to concrete block walls, where they are poured in place during construction. Vermiculite is a mica-like mineral that, when heated, puffs up. It can then be used as an insulation material. Most vermiculite contains small amounts of asbestos, and can therefore have the same negative health effects. However, some experts think that the heat used in the puffing up process may cause the asbestos to decompose, resulting in a less toxic product. Perlite is made from a silicate volcanic rock. It is a very dusty material and is sometimes treated with silicone. Breathing any type of dust can be harmful to health and should be avoided if at all possible. Some sensitive people can react to the silicone. WHAT TO DO If insulations are well sealed from the living space, they cannot introduce fibers, particles or gases into the air breathed by the occupants. In new construction, an airtight house will insure that the insulation remains where it belongs. Infiltration not only allows outdoor air to enter the house, it also can bring with it bits of insulation and outgassing fumes. Reducing infiltration can therefore reduce the chances of insulation contaminating the indoor air. Of course, when tightening up a house to control infiltration, fresh air should be introduced mechanically, since we all need fresh air to breathe. The use of heating ducts having fiberglass that is exposed to the airstream should be generally be avoided because small glass fibers can break off and enter the air. Insulation installers should wear clothing and gloves that protect their skin. Dust masks should be worn to protect the lungs. Paper "nuisance" dust masks are of almost no help - a high quality mask is necessary. Since many insulations can outgas undesirable odors, fresh air is also necessary during installation. A portable fan in a window or doorway will help to move the air through the house during construction or remodeling. If you are having an insulation such as cellulose pumped into the walls, have the installer monitor the inside of the house during the installation process to make sure that it does not filter indoors. It may be necessary to place tape over electrical outlets to seal them until the job is complete. If the standard commercially produced products seem too offensive, there are a couple of less toxic insulations available that are not widely used because of their higher cost. One is a new product called Air Krete, the other is a very old, natural product: cork. Cork is the outer bark of an evergreen oak tree that grows around the Mediterranean Sea. Surprisingly. it is vermin resistant and even termites shy away from it. It is generally ground up after it is removed from the tree and then processed into sheets. It will retain its light brown color if a synthetic binding agent is used to hold the granules together. This synthetic resin could bother sensitive people. It may contain phenol or formaldehyde resins. Some cork is processed without a binder being added. By steam baking the granules in a mold, the natural resins from the cork act to bind it together. Steam baked cork has a somewhat burnt smell and is dark brown in color. While the burnt odor will dissipate with time, some individuals may find the aroma offensive. For them, an easy solution would be to use the virgin cork granules directly from the tree. This can easily be poured in place in areas such as open attics. The main drawback to using cork is its cost, which ranges from $1.30 to $1.80 per square foot for the 2" thick steam baked variety. Manufacturers in the U.S. include Dodge Cork Co., Inc. and Rector Mineral Trading Corp. Air Krete has been on the market since 1983. It is a foam product that must be installed by trained applicators. It is roughly the consistency of shaving cream when it is put in place, then it quickly becomes more rigid. While it is easier to install it in an existing wall by injecting it into holes drilled in the siding, it can also be used in new construction. Costs range from $.80 to $1.30 per square foot for installing it in a 3 1/2" thick wall. Unlike other synthetic foam products, Air Krete is a cementitious material. This means that it is more closely related to concrete than to plastic. As a result it is almost completely odor free. In fact, it is being promoted as being non-toxic, since it contains "no formaldehyde or any other known toxic substances." While a very few sensitive people do find it somewhat offensive, it is generally quite inoffensive. Since Air Krete must be installed by licensed applicators, it is not available is all parts of the country. Like many potentially problematic materials in use today, if some basic precautions are taken, health problems can be minimized. Hopefully, in the future less harmful materials will be available. If you found this article helpful, you'll want to check out our books and videos, all of which contain a wide variety of in-depth information.
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