Frequently Asked Questions
Concerns about indoor environments
- Can mold make me sick?
- Can formaldehyde affect my health?
- Do I need an air cleaner, what kind should I buy?
- Does cleaning the ductwork in the home reduce indoor air contamination?
- Does the Florida Department of Health in Volusia County test for mold?
- How do I solve a mold problem?
- What about Carbon Monoxide?
- What about house dust?
- What about lead poisoning?
- What are the health effects of asbestos?
- What is Radon?
1. Can mold make me sick?
Mold can affect the health of people who are exposed to it. Exposure occurs primarily by breathing spores or other tiny fragments. Exposure can also occur through skin contact (for example, by touching moldy surfaces) and by swallowing it. The type and severity of health effects that mold may produce are difficult to predict. The risks can vary greatly from one location to another, over time, and from person to person. People having mold reactions often report problems such as: nasal and sinus congestion; cough; wheeze/breathing difficulties; sore throat, skin and eye irritation and upper respiratory infections (including sinus). On rare occasions, more serious problems can develop. Mold-related symptoms typically disappear when the mold is eliminated from the indoor environment.Top of Section
2. Can formaldehyde affect my health?
Small amounts of formaldehyde are harmless but can be irritating and toxic at higher concentrations. The indoor and outdoor air usually contains formaldehyde concentrations of 0.06 ppm (parts per million) or less. This concentration of formaldehyde is typically harmless to the public. Airborne concentrations at or above 0.1 ppm can cause symptoms such as watery eyes, burning sensations in the eyes, nose and throat, nausea, coughing, chest tightness, wheezing and skin rashes. Higher concentrations may trigger asthma attacks in asthmatics. People with formaldehyde sensitivity can experience these symptoms at concentrations below 0.1 ppm. At 100 ppm, it can be immediately dangerous to life and health. Formaldehyde has also been observed to cause cancer in laboratory animal studies and may cause cancer in humans. Humans are typically exposed to levels that are much lower than what was used in the scientific studies. Therefore, any risk of cancer is believed to be small at levels normally encountered by the public.
People who suspect they are experiencing formaldehyde-related symptoms should work closely with a knowledgeable physician to verify that it is causing their symptoms. Those who have adverse reactions to formaldehyde may want to consider avoiding the use of pressed wood products and other formaldehyde-emitting goods. Even if you do not experience such reactions, you may wish to reduce your exposure as much as possible by purchasing furnishings and wood products that emit less formaldehyde.Top of Section
3. Do I need an air cleaner, what kind should I buy?
The United States Environmental Protection Agency (USEPA) has researched the issue of air filters and duct cleaning in their publication Residential Air-Cleaning Devices: A Summary of Available Information. The following is an excerpt from that document:
"Some air filters, under the right conditions, can effectively remove small particles which are suspended in air. However, controversy exists as to the efficacy of air filters in removing larger particles such as pollen and house dust allergens, which rapidly settle from indoor air. In assessing the ability of an air cleaner in removing allergens, one should consider the relative contribution of airborne to surface concentrations of the allergens, particularly in the case of pollen and house dust allergens where natural settling may be so rapid that air cleaners contribute little additional effect. Animal dander may settle more slowly, although, again, the surface reservoir far exceeds the amount in the air. Furthermore, control of the sources of allergens and, where allergens do not originate outdoors, ventilation should be stressed as the primary means of reducing allergic reactions."
To paraphrase the above excerpt in layman’s terms, some allergens are small and can float in the air for a long time while others are large and rapidly fall to the floor or other surface (like furniture). Air filters, as the name implies, can only remove the allergens if they are suspended in air (floaters). If the allergen you are reacting to is a “floater”, an air filter may be able to remove it and alleviate your symptoms. If it is a “sinker,” the allergen will probably not be in the air long enough for the air filter to “catch” it so its use is unlikely to have a significant beneficial effect. The most effective way to solve your problem is to prevent allergens from getting into your house and if that is not possible, provide adequate ventilation (aka “fresh air”) to dilute their concentration.
The United States Environmental Protection Agency recommends consumers refer to either of these publications before purchasing a device:
Air Cleaners, from Rutgers Cooperative Extension
Residential Air-Cleaning Devices: A Summary of Available Information, from EPA
4. Does cleaning the ductwork in the home reduce indoor air contamination?
Why do you want to clean your ducts? If they are “dirty” and you want to remove the debris, duct cleaning may be appropriate. If your goal is to use duct cleaning to solve an indoor air-related health problem, duct cleaning is unlikely to be effective. An excellent discussion of this issue can be found in the EPA document, Should You Have the Ducts In Your Home Cleaned? The following discussion is an excerpt from this document:
"Duct cleaning has never been shown to actually prevent health problems. Neither do studies conclusively demonstrate that particle (e.g., dust) levels in homes increase because of dirty air ducts. This is because much of the dirt in air ducts adheres to duct surfaces and does not necessarily enter the living space.
It is important to keep in mind that dirty air ducts are only one of many possible sources of particles that are present in homes. Pollutants that enter the home both from outdoor and indoor activities such as cooking, cleaning, smoking, or just moving around, can cause greater exposure to contaminants than dirty air ducts. There is no evidence that a light amount of household dust or other particulate matter in air ducts poses any risk to your health."
Air duct cleaning may be indicated in gross contamination situations such as:
- Ducts are infested with vermin. (e.g. rodents or insects)
- Ducts are clogged with excessive amounts of dust, tobacco ash and debris and/or particles are actually released into the home from your supply registers when used.
- Substantial visible mold growth present in hard surface (e.g. sheet metal) ducts or on other components of your heating and cooling system.
5. Does the Florida Department of Health in Volusia County test for mold?
The Florida Department of Health in Volusia County does not typically conduct mold testing in our investigations. There are no standards for molds in living and working environments, so it’s very difficult to interpret testing results. If the mystery material in your house looks or smells like mold, it probably is. Don’t continue to expose yourself waiting for a mold test. It is important to protect your health and property by stopping the moisture causing the growth and eliminating mold from the house as soon as possible. If you absolutely must know what that black slime is on your wall, it is recommend that a lab with Environmental Microbiology Laboratory Accreditation Program (EMLAP) certification from the American Industrial Hygiene Association be used.Top of Section
6. How do I solve a mold problem?
The critical step in solving mold problems is removing the moisture source and removing contaminated materials. Repair of the defects that led to the moisture problem should be conducted in conjunction with fungus removal. Once the moisture source has been eliminated, building materials supporting fungal growth must be remediated as rapidly as possible. Specific methods of assessing and remediating fungal contamination should be based on the extent of visible contamination and underlying damage. The simplest and most expedient remediation that is reasonable and properly and safely removes fungal contamination, should be used.Top of Section
7. What about Carbon Monoxide?
As the weather turns cooler and people start using their heaters to warm their homes the potential for carbon monoxide poisoning increases. Carbon monoxide is an odorless and colorless gas. Unless you have a meter to measure the gas level you may not know you are being poisoned.
There are many sources of carbon monoxide poisoning that are associated with heating your home.
- Gas stoves
- Leaking chimneys
- Unvented kerosene and gas space heaters
- Wood stoves
Carbon Monoxide is formed when fuel is burned. To prevent the gas from reaching deadly levels you can make sure your fuel-burning heater is properly vented. Always open the flue when the fireplace is in use, wood burning stoves and kerosene heaters should be properly vented to the outdoors. Trained technicians should periodically inspect furnaces and fireplace chimneys.
The symptoms of carbon monoxide poisoning are similar to the flu and include the following:
- Irregular breathing
A simple way to insure you and your family's safety is to purchase a carbon monoxide detector. These detectors are sold at most stores that sell smoke alarms. The carbon monoxide detector works just like a smoke detector, alarming the occupants of dangerous levels of the poisonous gas.Top of Section
8. What about house dust?
House dust is the most common indoor pollutant and is a major contributor to indoor environment problems. However, the public rarely implicates it as the cause. It is a mixture of many things. A speck of dust may contain fabric fibers, insulation, skin, animal dander, dust mites, bacteria, cockroach parts, mold spores, food particles and other debris. Another dust problem that is occasionally encountered is a phenomenon known as “sooting”. Sooting is an unexplained dark mark or film on an interior wall, carpet or furniture surface. Unlike house dust, sooting is caused by a carbon-generating source and is usually created during a combustion process. Sooting can look like and it is frequently mistaken to be mold. Common causes of sooting include the indoor use of tobacco, candles and gas appliances.
House Dust and Sooting Health Effects
House dust is a common cause of year-round runny or stuffy nose, itchy, watery eyes and sneezing symptoms. Dust can also make people with asthma experience wheezing, coughing and shortness of breath. Animal dander, house dust mites and cockroaches are the most common substances in dust that cause these symptoms. Health effects can occur even though there are no visible signs of dust. While sooting can cause significant aesthetic problems, it is not normally considered to be a health threat.
Solving House Dust and Sooting Problems
Many materials in house dust cannot be removed by typical housekeeping methods. For example, no matter how vigorously one dusts or vacuums, the number of dust mites present deep within carpeting, pillows, and mattresses will not be reduced. Vigorous dusting, sweeping and vacuuming can put more dust into the air making symptoms worse. Use of a vacuum with HEPA filtration and dusting with a damp or oiled cloth is recommended for reducing ambient house dust. Ideally, someone other than the dust-sensitive person should do the cleaning. If the dust-sensitive person must clean, they should wear a mask. Use of a vacuum with HEPA type filtration may also be advisable. The best approach to resolving house dust-related health problems is to consult with an allergist to identify what the affected person is allergic to and then eliminate those allergen contributors from the indoor environment. More detailed information about common allergens in house dust, their health effects and abatement recommendations can be found in the internet links listed below.
It is extremely difficult for a homeowner to resolve a sooting problem without professional help. Resolution of these problems typically involves diagnostic tests of the house (including blow-door and leak tests), HVAC system measurements, infrared measurements of wall insulation and air current studies. These types of studies are beyond the abilities of do-it-yourself homeowners and most health department staff. It is therefore recommended that a professional with extensive experience in such investigations be contacted.Top of Section
9. What about lead poisoning?
There are many sources of lead in the environment because of the widespread use of lead in the past. For most households, and for most children, the major source of lead is contaminated dust. The most important sources of lead contamination of dust are from old paint and from leaded gasoline (now banned for most uses). Near major traffic corridors, soils are sometimes heavily contaminated from the prior use of leaded gas. (As an element, lead does not decompose, and it tends to stay in place over the years.) If this soil is tracked into the house, it becomes an important health hazard. Other minor sources can contain lead as well, such as older, vinyl mini-blinds.
Play areas with lead contamination can be a source of exposure due to hand-to mouth activity. Frequent handwashing is especially important. Landscaping (grass, dense shrubs) can keep kids from coming in direct contact with contaminated soils. Soils of lands used as orchards in the 1940s may also be contaminated with lead (and arsenic) from pesticides used during that era.Top of Section
10. What are the health effects of asbestos?
Asbestos fibers enter the body primarily through inhalation (breathing) or ingestion (eating, drinking). Many of the fibers will become trapped in the mucous membranes of the nose and throat where they can then be removed, but some may travel deep into the lungs, or, if swallowed, into the digestive tract. Once they are trapped in the body, the fibers can cause health problems. These health problems take years to develop. Diseases that have been attributed to asbestos exposure include asbestosis, mesothelioma and gastrointestinal cancers. Asbestos workers (i.e., working 40 hours/week - 48 weeks/year) who were smokers and not properly protected, have increased risk of developing lung cancers. The incidence of lung cancer in people who are directly involved in the mining, milling, manufacturing and use of asbestos and its products is much higher than in the general population. It is not known what amounts of asbestos are hazardous over what periods of time. It is therefore important that exposures to asbestos be kept as low as possible.Top of Section
11. What is Radon?
Radon is an odorless, tasteless gas. It occurs from the natural radioactive decay of uranium and radium in the soil. The radioactive decay products of radon are charged ions. The ions have a static charge that enables easy attachment to water vapor, dust, and smoke particles in the air. Radon is measured in units called picoCuries per liter (pCi/L) of air. Annual radon levels above r pCi/L are considered excessive and require remediation.Top of Section