Janus Revisited, Molds Again

Abstract

WHAT components of indoor air cause irritation, headache, and fatigue, diminish concentration, and impair recall memory? Subsequent to the energy crisis of 1973, buildings are ”tighter,” they leak less heat and cold than older buildings, and more people are bothered and become ill from indoor exposures. For more than 30 yr the indoor air syndrome has been studied. This air contains materials outgassed from construction and decorations, as well as from smoking and other activities in a building.’ Burge et a1.2 sorted components in air into various categories of total volatile organic chemicals: solvents, formaldehyde, insecticides, degreasers, waxes and wax strippers, nonorganic cleaning agents (e.g., ammonia, chlorine), and many others. During the past decade, an association has surfaced between occupants’ symptoms and molds that grow on surfaces and within walls and feed on the cellulose from the paper that encloses the gypsum of d r y ~ a l l . ~ Water damage and high humidity in walls encourage the growth of molds. Air-conditioning ducts condense water from the air and collect nutrients in dust that contain mold spores that grow and become widely distributed indoors. Such observations are consistent with a diminishment or avoidance of individuals’ symptoms in response to more exchanges of building air with outdoor air. Subsequent to 1950, changes in materials used for the construction of building interiors have set the stage for the growth of molds indoors. Wood or metal framing of walls and ceilings is covered with sheets of drywall and gypsum board-a virtual ”sandwich” of calcium sulfate between layers of paper. Drywall replaced cedar lath-sometimes wrapped with chicken wireand it was covered with cement plaster and had a finish coat of calcium oxide-termed “quicklime.” Older era wall layers were strongly alkaline, and, therefore, growth of molds was not favored. In fact, Joseph Lister, the father of aseptic and antiseptic surgery, used quicklime to wash instruments and hands, and he used it to dress wounds (e.g., compound fractures4). It i s almost impossible for molds and bacteria that harm people to grow on lime plaster or on concrete. In contrast, mold growth is encouraged on damp paper-and with the same ease as occurs on bread. Mold spores survive (1) desiccation, (2) temperatures of 500 OF, and (3) efforts to kill them with strong chemicals. The Bible, in Leviticus, warned of the harmful effects of molds. Mold toxins have altered history. Such molds include ergot from claviceps species, aflatoxins from Aspergillus, and trichothecenes from Fusarium and Stachybotrys. Conversely, products of the genus Penicillium revolutionized medical treatment of bacterial infections. Coumadin from sweet clover spoiled by pastinaca species make furanocou mad i ns that prevent blood clotting in individuals who have diseased blood vessels. Furthermore, xanthotoxin from the pink celery rot fungus causes photosensitivity of human skin accompanied by erythema, necrosis, and scaling5 In the Middle Ages,6 ergot molds on cereal, especially rye grains, caused epidemics of spontaneous abortions and dry ischemic gangrene (termed “St. Anthony’s fire”). Perhaps the most profound effects were on the human mind: dreams were produced, trances occurred, and resulting aberrant behaviors led to accusations that consumers were possessed by the devil-all of which were punishable by death. Recall that in Salem, Massachusetts, witches were put to death. During the starvation and privation of Eastern Europe in and after World War I t , individuals ate moldy feed grains, especially millet, that had wintered over in the fields.’ Wetness and weathering spoiled the grains, and Fusaria (of the Sporotricilbilla group) produced trichothecene. These toxic chemicals are also produced by Stachybotrys and claviceps-both of which consume cellulo~e.~ Severe respiratory illness, petechial hemorrhages of the skin and bowel, anemia, and leukopenia justified the name “alimentary toxic ale~kia.”~ Aspergillus f laws and A. furnigatus aflatoxins are important causes of hepatocellular carcinoma in subSaharan Africa. Other fungi, including Penicilliurn, isolated from dairy cattle feed, produce tremors in animals. Moldy maize contains zearalenone (i.e., an endocrine disrupter), which is produced by Fusariurn roseum that grows in corn and barley. When fed to swine, it produces hyperestrogenism with vaginal swelling and eversion. One questions whether the deaths of some swine resulted from the presence of trichothecenes in the moldy maize. Experimental administration of zearalenone produces pituitary tumors and hepatocellular cancers in female rats (1. Huff, personal communication). Recently, the old horror stories about the effects of mold have resurfaced, and understanding of how molds affect animal and human physiology has converged