Environmental
Scientists and Engineers
"Protecting People in their Environments"

Home | Environmental Services | Consulting Services | Laboratory Services | Field Operations | Training Services

About Us | Contact Us |  UST Test Forms and Scheduling  | Links | Site Map

  Mold Topics

Mold Basics

Mold is made up of microscopic organisms which feed on decaying plant and animal material and produce tiny spores which many people find highly irritating to the lungs and nasal passages. In addition to allergic symptoms, molds produce mycotoxins which, when ingested, can make one very sick. People with compromised immune systems can contract systemic infections from exposure to mold (i.e. through open sores, surgical lesions, respiratory infections). In summary, mold is not a good thing to have around the house. With the wet weather we’ve recently experienced, many of us have found that we have leaking basements, sky lights, or windows, etc. in our homes. Mold will grow in any chronically damp spot.

It is not possible to completely rid your house of mold since it is ubiquitous, mold spores are found everywhere in the environment. Airborne concentrations are important, and you should try to keep your exposure to a minimum. If you find places within your home that are wet due to leaks, condensation, or flooding, you can halt the growth of mold by stopping the source of water leakage, and getting rid of the affected materials (wallboard, wood, or other porous surface).

A typical example of the type of mold we see in our refrigerators—penicillium The mycotoxin produced by penicillium was the first antibiotic discovered. In this case we were able to use a mold to our advantage in curing disease. There are many other useful molds, used for baking, and brewing wine or beer, so we need not fear all molds, only those that make us ill.

back to top

MOLD REMOVAL IN YOUR HOME

Who should do mold cleanup? If the area in question is 10 square feet or less, you might attempt to remove it on your own. It is better to hire a professional mold remediation company if:
1) there has been >10 square feet of water damage 
2) you suspect that the heating and ventilating system is contaminated
3) there has been sewage contamination
4) you have health concerns.

If mold is visible, it isn’t necessary to call in a consultant to sample it, but to assure that the cleanup has been done correctly after the removal company has finished their work, a reliable environmental firm should sample air and surfaces in the cleanup area.
back to top

MOLD CLEAN-UP GUIDELINES

First, fix plumbing leaks or other water problems and dry the area thoroughly. Improve air circulation in bathrooms and kitchens where cooking produces moisture. Wrap pipes on which water condenses. Install a dehumidifier to help dry out damp rooms. If the contaminated surface is smooth and non-porous, mold can be scrubbed off with a detergent and the area disinfected with a biocide.

Do not attempt to paint over moldy areas. The paint will eventually peel and the problem will not be permanently solved. Do not expose yourself or others to mold in the process of cleaning. Protective clothing should be worn (see below), and people and animals kept out of the work area.
back to top

PROTECTION WHILE CLEANING MOLDY AREAS

Avoid breathing mold spores by wearing a respirator. A type P-100 respirator which screens out particulates will suffice. They are sold in some hardware stores or may be ordered over the internet. The respirator must fit securely over your breathing area or it will be ineffective.

Prevent mold spores from getting into your eyes by wearing goggles without ventilation holes.

To protect your hands from mold, detergent, and biocide, wear long gloves which extend to the middle of the forearm. Ordinary household gloves made of rubber, neoprene, nitrile, or polyurethane will do.

Wear either old clothing that can be washed, or a disposable coverall.

We do not recommend the use of Clorox as a biocide or the use of ionizing radiation or ozone generating devices for the reduction of mold spores in air.

WHAT TO DO ABOUT HIDDEN MOLD.

Mold can be hidden behind wall paper, the back side of drywall, or paneling, under carpets, on the tops of ceiling tiles, in ductwork. If you can smell mold, it is there.

Tearing out drywall or peeling off contaminated wallpaper can release a massive amount of spores, so it is best to hire a professional to do this kind of removal.

You will be rewarded with better health and more comfortable living conditions if you are conscientious about mold identification and remediation in your home and workplace.

Brooks Laboratories is a full service environmental laboratory in Norwalk Connecticut. Our analysts can identify specific types of mold and differentiate between those that are potentially toxigenic vs. those which are not.

Our next newsletter will list the most commonly found species of household mold, and the diseases they cause.†

*Information is a condensation of the EPA’s booklet : “A Brief Guide to Mold, Moisture, and Your Home”.
back to top

INTRODUCTION

Most of us spend about 75% to 90% of our time indoors, so it is important for our health to have the air quality of our indoor environment as free of toxins as possible. Spores, mycotoxins, and the volatile organic compounds (VOC’s) that molds produce are among the many indoor (and outdoor) pollutants we are exposed to.

There are believed to be about 1.5 million species of fungi. At least 1,000 species have evolved to live on materials we use to build our homes and offices with.

When there is water damage to wallboard, rugs, furnishings, and finishes mold will form colonies on damp, porous surfaces.

We are affected by the spores , mycotoxins, and (VOC’s) in the following ways:

1. allergic responses

2. infection

3. toxicity

Of these, allergic responses are the most common. Infection is a problem in individuals who have compromised immunity (i.e. cancer patients undergoing chemotherapy, organ transplant patients, and individuals with HIV/AIDS), also for pregnant women and infants.

Toxicity is perhaps the least common response, and is due to close contact or ingestion of mycotoxins— substances that are produced by mature fungi under ideal growth conditions.

Sick building syndrome is believed to be due, at least in part, to exposure to mold and it’s toxins.

It is prudent to correct any chronically wet conditions in your home or office and remove any materials which have been colonized by fungi.

back to top

---

HEALTH EFFECTS

Allergic reactions are caused by the fungal spores which land in the nasal mucosa, eyes, and lungs— causing rhinitis, sinusitis, eye irritation, cough and asthma aggravation.

In some occupational environments, usually agricultural in nature, one can be exposed to high concentrations of mold spores and develop what is known as “farmer’s lung” or hypersensitivity pneumonitis (HP).

Commonly occurring molds which cause allergies are: Alternaria alternate, Botrytis cinera, Cladosporium herbarum, Cladosporium macrocarpum, Drechslera, Botrytis, Rhizopus, Trichoderma, and Epicoccum purpurascens.

Some pathogenic Fungi can infect even the relatively healthy. Examples of this kind of fungi are: Aspergillus, Blastomyces, Coccidioides, Cryptococcus, and Histoplasma. They produce the infections aspergillosis, blastomycosis, histoplasmosis, cryptococcosis, and coccidioidomycosis.

Aspergillosis causes illness in three ways; as an allergic reaction in people with asthma; as a colonization and growth in an old healed lung cavity from previous disease (such as tuberculosis or lung abscess) where it produces a fungus ball called aspergilloma; and as an invasive infection with pneumonia that is spread to other parts of the body by the bloodstream. The invasive infection can affect the eye, causing blindness, and any other organ of the body, but especially the heart, lungs, brain, and kidneys. The third form occurs almost exclusively in people who are immunosuppressed because of cancer, AIDS, leukemia, organ transplants, high doses of corticosteroid drugs.

Blastomycosis is a rare fungal disease occurring most often in people living in the south-central and midwestern US and Canada. Exposure to soil is the key risk factor. The disease usually affects people with compromised immune systems. Men are more likely to be affected than women. Lung infection may produce no symptoms, but when the infection is widespread, skin lesions or bone lesions may appear and the urogenital system (bladder, kidney, prostate, and testes) may be affected.
 

Histoplasmosis is a fungal infection occurring most offen in the southeastern, mid-Atlantic, and central states. The lungs are the portal of entry for this infection. Histoplasma grows as a mold in soil and infection results from inhalation of airborne fungal particles. Soil contaminated with bird or bat droppings may have a higher concentration of mold. Histoplasmosis may have no symptoms, there may be a short period of active infection or it can become chronic and spread throughout the body. Most patients with symptomatic histoplasmosis will have a flu-like syndrome and pulmonary complaints related to underlying pneumonia. Individuals with chronic lung disease (emphasema, bronchiectasis) may be at higher risk of a more severe infection. Up to 10% of patients may have complications involving the skin, bone/joints, or the lining of the heart. In a small proportion of patients histoplasmosis may be widespread and involve the blood, and linings of the brain, adrenal glands and other organs.

Cryptococcosis is caused by inhalation of the spores of the fungus Cryptococcus neoformans which is found in soil. Once inhaled, infection with cryptococcosis may heal on its own, remain localized in the lungs, or spread throughout the body. Most cases occur in people whose resistance to infection is low. In people with normal immune systems, the pulmonary form may have no symptoms. However, in people with impaired immune systems the organism may spread to the brain. The onset of neurological symptoms is gradual. The majority of people with this condition have meningoencephalitis (swelling and irritation of the brain and spinal cord) at the time of diagnosis. Cryptococcosis is one of the most common life-threatening fungal infections in AIDS patients.

Coccidiodomycosis is caused by inhalation of the spores of the fungus Coccidioides immitis which is often found in desert regions. In 60% of infections there are no symptoms and are only recognized later by a positive coccidioidin skin test. In the remaining 40% of cases, symptoms range from mild to severe. In disseminated disease, spread of the infection to the bones, lungs, liver, meninges, brain, skin, heart and pericardium may take place. Meningitis occurs in 30-50% of cases of disseminated disease. The course of the disease may be rapid for immuno suppressed patients.

back to top

---

VOLATILE ORGANIC COMPOUNDS

Many molds produce volatile organic compounds (VOC’s) - alcohols and ketones that give mold it’s musty odor. The principal volatile of molds found in damp buildings is ethanol. Other compounds are 3-methylbutanol, octen-3-one, octan-3-one, octan-3-ol, 2-octen-1-ol, 1-octen-3-ol and 1,10-dimethyl-trans-9-decalol. There is little evidence that they cause health effects in humans, although there is some mention in the literature of their causing nasal irritation and stuffiness.

All fungal cell walls including spores and hyphae contain beta-1,3-D-glucans, an immunosuppressive glucose polymer causing cell transformation and inflammation. Exposure to this compound causes a decrease in the number of pulmonary alveolar macrophages. Animal experiments have shown that this material also acts synergistically with bacterial endotoxins to produce airway inflammation. A variety of undesirable effects occur if sufficient numbers of these cells are damaged. Exposure to fungal spores, alone and in combination with bacteria and viruses can be expected to promote viral and bacterial disease and a decrease in general well being.

back to top

---

MYCOTOXICITY

Mycotoxins are produced by molds as a means of protection (to kill competing fungi). They are produced only under very specific conditions—ideal heat, moisture, and maturity of the fungus. Mycotoxins are large molecules and not especially volatile, therefore it is necessary to come in direct contact with them in order to be poisoned by them. One of the more famous mycotoxin-producing molds is Stachybotrys chartarum, a black mold found occasionally in people’s homes. It was originally found as a contaminant of hay in stables.

Horses fed with the hay died from stachybotryotoxicosis. There have been several well documented incidents of adult humans suffering a range of illnesses following exposures to spores of Stachybotrys chartarum in damp buildings. A low concentration of toxic mold metabolite “Satratoxin H” is produced by S. chartarum and can cause cellular death and hemorrhage.

Indoor air quality issues associated with exposure to mold and mycotoxins are becoming of greater importance. A few governmental agencies have published guidelines on mold assessment and remediation. Most mold genera encountered are “toxic” and allergenic, and can be considered to constitute a serious problem.

Brooks Laboratories specializes in mold identification and remediation. If you have questions, please call us at (203)853-9792

back to top

---

References:
National Library of Medicine and the National Institute of Health

Singh, Jagjit; “Toxic Moulds and Indoor Air Quality”, Indoor and Built Environment 2005 14:3-4:229-234

Pieckova, Elena, “Aspergillus sp. In Dwellings and Health Implications of Indoor Fungi”, Institute of Preventive and Clinical Medicine.