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Toxic Mold

Molds also produce secondary metabolites such as antibiotics and mycotoxins (a poisonous substance produced by a fungus). Sometimes it is possible to isolate antibiotics from the molds themselves in order to utilize some of their properties in fighting infections. Secondary metabolisms are not necessary for maintaining the existence of a mold---either by creating energy or synthesizing structural components, informational molecules or enzymes. They do, however, function to provide molds with advantages over other mold and bacteria and are toxic to certain plant and human cells.

Toxic conditions exist when a human has exposure to these mycotoxins---either through ingesting mycotoxin-containing mold spores or with skin contact to mold itself. Mycotoxins are nearly all cytotoxic (substances produced by microorganisms that are toxic to individual cells), which disrupt various cellular structures such as membranes, and interrupt important processes, including protein, RNA and DNA synthesis.

Mycotoxins vary in how dangerous they are for humans. Mycotoxins pose a threat to larger organisms not because they are specifically targeting them, but rather because these large organisms inadvertently come across the byproduct of the competing molds all vying for the same ecological niche. Numerous mold types produce mycotoxins, including some found indoors in contaminated homes and office buildings. Another factor that determines the mycotoxins that are produced by specific molds usually depends on the materials or organisms that they grow on.

It used to be thought that dangerous molds were primarily contaminants in foods. This notion is quickly changing. Recently, researchers have become more concerned with multiple mycotoxins that derive from many types of mold spores growing in moist indoor environments. Health effects from exposures to such mold mixtures can differ from those related to single mycotoxins in controlled laboratory exposures. Although it is difficult to predict how exposure to multiple toxigenic molds can affect an individual (they can synergize the effects), the following provides possible poor health effects from mycotoxin exposure to multiple molds indoors.

  • Problems with the vascular system. Increased vascular fragility, possibility of hemorrhaging into body tissues. Possible molds include aflatoxin, satratoxin, roridins.
  • Problems with digestive system. Diarrhea, vomiting, intestinal hemorrhage, liver effects (such as necrosis and fibrosis). Aflatoxin results in deleterious effects on mucous membranes.
  • Problems with respiratory system. Including respiratory distress, and bleeding from the lungs.
  • Problems with nervous system. Tremors, lack of coordination, depression, and headaches.
  • Problems with cutaneous system. Symptoms include rash, burning sensation, and sloughing of skin.
  • Problems with urinary system.
  • Problems with reproductive system. Including infertility, changes in reproductive cycles, etc.
  • Many mycotoxins can produce changes or a weakening of the immune system.

Unfortunately, not all types or species of molds have been tested for the presence of mycotoxins. The production of toxins varies according to the type of mold, the substrate on which it grows, and seasons of the year.