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MOLD
First, one must understand how
mold lives. Many molds need simple things to exist and
colonize. Most require a type of moist intrusion or
humidity, otherwise known as "the wicking effect. " In some
cases, it can take as little as 24 hours for this process to
begin. After the source of the moisture has stopped, it does
not mean that the mold has stopped growing.
Some molds are cryophytes (these adapt to low temperatures),
some are thermo tolerant (they adapt to a wide range of
temperatures) and some are thermophiles (they adapt to high
temperatures). Depending on the species, these microbes will
grow just about anywhere. Mold requires a compatible
temperature for each species. Environmental factors
(temperature, nitrogen, oxygen, etc. ) are necessary
compounds for indoor molds to thrive.
Mold also needs an organic source of food. People might be
confused as mold can grow on glass, tile, stainless steel,
cookware, etc., but it is generally feeding off of some
organic source deposited on this material (oils, film, dirt,
skin cells, etc. ). The fiberglass insulation people like to
say that mold does not grow on their product which is a
fairly true statement, however, it grows on the organic
debris that become trapped in their products. Mold also
grows on things such as wood, fabric, leather, gypsum,
fiberboard, drywall, stucco, and many insulation fibrous
materials. All molds require some form of moisture to grow
however, like temperature, the amount of moisture varies for
different species. Some are xerophillic (colonize under very
dry conditions) some are xerotolerant (colonize under a wide
range of moisture levels) and some are hydrophilic (colonize
at high moisture levels). It does not have to be a leak. . .
Humidity or moisture content of the substrate can often be
sufficient (relative humidity 50% start becoming problematic
in many indoor cases.) It can spread very easily through any
HVAC system.
Mycotoxins are examples of chemical substances that molds
create generally as secondary metabolites, thought to
possibly play a role in either helping to prepare the
substrate on which they exist for digestion, as defense
mechanisms, and some have suggested that they may be
produced when the organisms are under stress, which could be
related to competition/defense, or simply due to
inhospitable environmental conditions. The mycotoxins, which
are also neurotoxins (a toxin that is determined to cause
neurological damage), most commonly reach people from the
air, via spores from the molds in question. They are also
found in small particulates at times which may often
represent mold dust, small particles of mold that has dried
and turned to dust. Spores, when inhaled, can begin to
colonize in the sinuses and throughout the body, including
the brain, lung and gut after a period of time.
One of the mycotoxins, aflatoxin, is produced by the fungi
Penicillium, Aspergillus flavus and Aspergillus parasiticus.
Four different aflatoxins, B1, B2, G1 and G2, have been
identified with B1 being the most toxic, carcinogenic and
prevalent. Another very dangerous family of toxin producers
is Fusarium. The toxins zearalenone, trichothecenes or
moniliformin can be formed by various types of Fusarium
including F. moniliforme, F. oxysporum, F. culmorum, F.
avenaceum, F. equiseti, F. roseum, and F. nivale.
Under certain growth and environmental conditions, black
mold, otherwise known as Stachybotrys chartarum may produce
several different mycotoxins, including a very strong class
known as trichothecenes. Trichothecenes are also produced by
several common molds including species in the genera
Acremonium, Cylindrocarpon, Dendrodochium, Myrothecium,
Trichoderma, and Trichothecium. The trichothecenes are
potent inhibitors of DNA, RNA, and protein synthesis, and
have been well studied in animal models because of concern
about their potential misuse as agents of biological
warfare, due to their ability to destroy human health
(mentally and physically), and never show up in an autopsy.
Sick buildings are one of the three major causes of fungal
illness in industrialized nations today.
  
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