Health and Safety Hazards of Fungi, Mold and Microbials.

What you need to know about the hazards and your personal health and safety

Lately in the news, you can hear about scientific reports linking toxic molds (or better called fungi) such as Stachybotrys chartarum (a.k.a.: S. atra) with ill health in office buildings, schools and private homes. A well-documented medical investigation has been reported from New York City [Johanning et. al., 1996]. Two years later, the media informs us of cases of hemorrhagic lung disease in several dozen infants in Cleveland, Ohio, more than 10 infants die of complications of this disease [MMWR, NIOSH]. Newspapers carry stories of home owners or office workers who develop severe asthma and allergies after flooding or water damage occurs and building materials like wall paper, carpet, books, pictures and ceiling tiles show discoloration and start smelling because of fungal growth.

The greater the visible microbial damage, the higher the risk will be not only for the occupants, but also the cleanup workers. These home-owners or building occupants often need to conduct a very thorough professional cleaning and abatement of the moldy building materials, personal belongings and furniture, especially if they develop allergies or other hyper-sensitivities to the contaminated materials. This will require careful planning and good work procedures to minimize the inherent risks for cleanup workers and customers. The goal will be to achieve a level of cleaning that will be satisfactory for the customer (with potential environmental health problems and fungal intolerance) and cost-effective, as well as practicable, for the professional cleaners.

Fungi have been involved in human suffering since the beginning of time. Medically, only some of the many naturally occurring types of fungus are known to cause diseases in humans and animals.

Health Problems Related to Fungi:

The most notable species of Penicillium, Aspergillus, Paecilomyces and Fusarium and the already mentioned Stachybotrys, can be very hazardous to health under certain conditions. The natural occurring compounds produced by fungi that evoke a toxic response are called mycotoxins. Mycotoxins are the secondary chemical metabolites of the fungi, and are usually contained in the invisible spores. Toxicity can arise from exposure to mycoroxin-containing mold spores in the air, ingestion of contaminated food or through skin contact with the toxigenic molds. Aflatoxin (from A. flavus) has been recognized as the most potent carcinogen causing liver cancer if ingested in high concentrations.

Indoor air contains spores and hypha fragments of many different molds, but the most common is likely to be a species of Cladosporium, Alternaria and other fungi also typically found in normal outdoor environments. In "sick buildings," we can often find the toxigenic or allergenic fungi mentioned above. Wood, paper, surface coatings such as paint, soft furnishings, soil in plant pots, dust, shed skin scales, and cooked and raw foods can provide many opportunities for a fungal metabolism.

The following health problems can be related to fungi:

* asthma,

* hypersensitivity pneumonitis, humidifier fever,

* mucous membrane irritation,

* mushroom poisoning and mycotoxicosis.

Assessment and remediation

Guidelines for the assessment and remediation of indoor fungal contaminations have been established by the New York City Health Department (NYC-DOH) and the Canadian Mortgage and Housing Corporation. These are based on modern research results and best professional judgments.

It is not always cost effective and necessary to measure airborne fungal concentrations unless indicated by medical needs or industrial hygiene requirements. However, it is often unwise to wait to take action until "all comprehensive air and bulk testing is completed."

The following steps are essential in the proper identification and clean up of fungal contamination:

1. Visual inspection

A visual inspection involves checking for the presence of visible mold growth in these locations:

* Window frames and on carpets (check backing in water-stained areas if possible);

* On ceiling tiles, and on any currently or formerly damp material made of cellulose (wallpaper, books, papers, shredded newspaper insulation);

* All accessible heating, ventilation, and air-conditioning components; check for any substantial indoor space with exposed soil such as unfinished basements or crawl spaces; and,

* Indoor plants, contiguous green-houses, attics with resident or seasonal birds, bats or other animals.

2. Sampling

If you suspect that your home or work environment has been contaminated, samples can be collected to confirm such contamination and determine what types of fungal species are present. It is highly recommended that such measures be carried out by experienced and trained processionals. Check with your local health department, yellow pages (industrial hygiene environmental services) or Internet sources such as www.EnviroCenter.com for a listing of qualified professionals.

3. Cleanup procedures and health and safety protection

The professional clean up should only be done by healthy people. If in doubt, ask your personal doctor or see an occupational health physician. People with a weakened immune system and severe chronic diseases such as Diabetes mellitus, renal and liver disease, immune diseases like AIDS, cancer or bone disease, or on medications that weaken the immune system (steroids, anti-cancer drugs, etc.) should not do such work because of the health risks and insufficient personal protective equipment (PPE). Individuals who are routinely involved in such cleanup work should be "medically cleared" by an occupational and environmental health specialist, and undergo proper respiratory fit testing. Currently, no special medical surveillance and monitoring rules have been written or are required. Based on our experience, it would be very prudent to follow guidelines similar to those for hazardous waste cleanup workers. For more information call, the Association of Occupational and Environmental Health Clinics 202/347-4976.

The cleanup, also called remediation, of larger scale fungal contamination is similar to asbestos abatement in respect to the containment and use of PPE. The clean up measures and type of PPE depend on the size of the problem. The guidelines established by the expert panel convened by the NYC-DOH has four levels -- although the type and amount of sampled fungi found in water damaged homes can vary greatly. A good indicator for the need of more stringent compliance will be if the home owners report symptoms and illnesses that are in time and place related to the damaged home.

Remediation Levels Based on Visible "Moldy" Surface Contamination:

Level 1:

Small isolated areas (visible contamination is 2 sq. ft or less)

Level 2:

Larger isolated areas (visible contamination is 2 - 30 sq. ft)

Level 3:

Large scale remediation (visible contamination is more than 30 sq. ft.)

Level 4:

HVAC systems

Make sure there is adequate ventilation and a supply of "fresh air" from outside. Read and follow instructions and Safety Data Sheets (MSDS) of all chemicals used in the cleanup. Use only well fitted respirators, and make sure the particle filter cartridges (best is a HEPA filter combined with an organic vapor filter) are fresh and not "used up." Use eye goggles, heavy work gloves or rubber gloves, wear rubber boots and a work uniform laundered in a professional laundry (the most practical and preferable are Tyvak-type disposable suits). As always, effective hygiene starts with hand-washing after handling of contaminated materials, especially if no gloves have been used. It is best to discard all damaged and moldy items, particularly if they are made from cellulose materials (paper, cardboard, drywall sheeting).

Clean-up workers are at risk of musculoskeletal injuries to the hands, backs, knees and shoulders. Avoid lifting heavy objects and awkward body postures. Workers wearing PPE are at risk of heat stress (especially in hot and humid climates), heat exhaustion, heat cramps and fainting. Drink plenty of fluids (more than 2 - 4 quarts per shift if necessary). Work in the cooler hours of the day. Use frequent rest periods. Monitor your pulse if possible and keep it around 120-130 beats per minute. If in doubt, ask your personal doctor.

For questions regarding proper personal protective equipment (PPE) call the local OSHA office or NIOSH (1-800-35 NIOSH).

Published by permission. [C] Association of Specialists in Cleaning and Restoration, Inc., All rights reserved.

Fungal Transmission Routes Include:

* Inhalation

Many of the dangerous mold spores and particles are invisible (10 microns) and can become airborne, especially if disturbed during cleaning and constriction work. When inhaled through the mouth and nose deep into the lungs, they may interact with the human tissue and blood system.

* Skin and eyes

Touching moldy surfaces such as furniture or coming in contact with plants, may result in local skin irritation (painful skin redness or mild swelling).

* Ingestion:

Several toxic fungal species can cause serious intestinal food poisoning, liver cancer (aflatoxin from Aspergillus flavus) or even death. Typically more than one fungus is identified in problem houses with water damage and dampness. A tow appear more problematic than others. For example, Stachybotrys atra has a high moisture requirement, so it grows where moisture has accumulated from roof or wall leaks, or chronically wet areas from plumbing leaks. This mold has a very tow nitrogen requirement, and can grow on water-saturated cellulosic materials such as paper, wallpaper, ceiling tiles, carpets (especially the jure backings), insulation material, wood-derived building materials and even general debris. Wet paper with greater than 97 percent water content tends to be more toxic.

Eckardt Johanning, M.D., M.Sc. Mr. Johanning is the medical director at the Eastern New York Occupational and Environmental Health Clinic in Albany, N.Y., Mount Sinai Medical Center.

Phil Morey, Ph.D., CIH Mr. Morey is a certified Industrial Hygienist employed by Air Quality Science of Atlanta, Ga.