UNIVERSITY PARK, Pa. -- Growing your own plants from seeds and cuttings can be fun and economical. But doing it "on the cheap" could cause a serious health problem, warns a specialist in Penn State's College of Agricultural Sciences.

"A dangerous fungus called Stachybotrys chartarum can colonize paper containers if they stay wet for an extended period," says Gretchen Kuldau, assistant professor of plant pathology.

Stachybotrys (pronounced stack-ee-bot-tris) can produce serious toxins that are absorbed in the lungs when the fungal spores are inhaled. Skin contact with the fungus can cause a painful dermatitis.

"While the paper in milk cartons and similar containers is treated to repel water," Kuldau says, "egg cartons and cardboard boxes generally are not. Once you fill them with soil, the paper becomes wet.

"Look for a heavy black patch of mold on the surface of paper or wood," Kuldau says. "The patch often looks sooty and may have white margins. Wet areas may be a little shiny or slimy." Any wet cellulose-containing product is a candidate for invasion, including:

• cardboard boxes that get wet and remain moist during storage
• newspapers used to shade flats of young plants
• newspapers stacked in moist places until thrown out
• wood or drywall that's wet from condensation or continuous contact with wet soil
• walls of flooded buildings

"You don't want to have continued contact with this fungus," she says. "Breathing the spores can cause a burning sensation in your nose and throat, a bloody nose, eye irritation, tightness in the chest, cough, fever, headache and fatigue. We don't know how many spores need to be inhaled for symptoms to occur."

Immune-compromised individuals (persons with HIV/AIDS, those undergoing chemotherapy treatment and pregnant women) as well as the young and the elderly likely will be more susceptible to the fungus.

If you find black mold on wood or paper products, Kuldau suggests the following:

• Keep the material moist to hold spores in place. "If you let the material dry, the spores become airborne," she says. "If the material is already dry, wear a respirator to avoid breathing the spores. A dust mask is not sufficient protection."
• While wearing gloves and protective clothing, place the wet materials in a plastic bag or other container that can be closed, then dispose of them.

"You might be able to treat problem areas to reduce the amount of fungus present," she says. "Mix a household bleach solution (1/4 cup of bleach per gallon of water), then spray it on contaminated surfaces using a hand-pumped garden sprayer. Thoroughly wet the surface, but avoid excessive runoff. Let the treated surface dry for six to eight hours."

If the fungus appears to grow back, Kuldau suggests trying a stronger solution (1 1/2 cups of bleach per gallon of water).

"When using bleach, be sure to wear eye protection and rubber gloves and ventilate the area well," she adds. "And never mix bleach with ammonia -- it creates toxic fumes."

To avoid growing Stachybotrys:

• Keep paper and wood products dry, off the ground and away from direct contact with moist soil.
• If you buy plants in recycled paper pots, watch for black patches of fungal growth on the pot surfaces. Dispose of pots with black fungus promptly, as described above.
• Don't grow plants in paper containers unless the paper has been treated to repel water. Even then, raise them off the soil on inverted plastic flats, or place them on benches or tables so the surfaces of the pots can dry.

For more information on molds in the home or other buildings, Kuldau suggests the Minnesota Department of Health's Web page "Mold in Homes" at http://www.health.state.mn.us/divs/eh/aialr/iair/moldfs.html, or the California Department of Health Services' "Mold in My Home: What Do I Do?" at http://www.cal-iaq.org/mold9803.htm.

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EDITORS: Gretchen Kuldau can be reached at 814-863-7232.

Contact:

Kim Dionis KDionis@psu.edu 814-863-2703 814-865-1068 fax