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Common Toxic Black Mold Symptoms
(1) "Cough, rhinitis, burning
sensation in the mouth, (throat) and
nasal passages, and cutaneous
irritation at (points) of toxin
contact"
(2) Nosebleeds are also
common, and tracheal bleeding was
occasionally reported. Whether such
mycotoxin effects explain the
symptoms seen in common building
exposures has been disputed. It has
been pointed out that, although the
mycotoxins are often associated with
disseminating fungal conidia, the
quantities present may not be
sufficient to explain the effects
observed.
(3) A number of mycotoxins or conidia of
mycotoxigenic fungi, however, have
also been shown to have effects such
as activation of pulmonary alveolar
macrophages (PAMs), DNA
fragmentation in PAMs, inhibition of
the oxidative burst killing
mechanism in PAMs, and slowing of
respiratory ciliary beat
(4) Such interactions with
immune mechanisms may explain some
symptoms not explained by toxicosis.
Careful study of occupants of
contaminated buildings suggests an
association between inhalation of
toxigenic fungi and nonspecific
respiratory symptoms
(5) Moldy Odors are released
from actively growing fungi may also
pose a health risk. Not all molds
produce mycotoxins, but numerous
species do (including some found
indoors in contaminated buildings).
Toxigenic molds vary in their
mycotoxin production depending on
the substrate on which they grow
(Jarvis, 1990). The spores, with
which the toxins are primarily
associated, are cast off in blooms
that vary with the mold's diurnal,
seasonal and life cycle stage
(Burge, 1990; Yang, 1995). The
presence of competitive organisms
may play a role, as some molds grown
in monoculture in the laboratory
lose their toxic potency (Jarvis,
1995). Until relatively recently,
mold poisons were regarded with
concern primarily as contaminants in
foods. More recently concern has
arisen over exposure to multiple
mycotoxins from a mixture of mold
spores growing in wet indoor
environments. Health effects from
exposures to such mixtures can
differ from those related to single
mycotoxins in controlled laboratory
exposures. Indoor exposures to
toxigenic molds resemble field
exposures of animals more closely
than they do controlled experimental
laboratory exposures. Animals in
controlled laboratory exposures are
healthy, of the same age, raised
under optimum conditions, and have
only the challenge of known doses of
a single toxic agent via a single
exposure route. In contrast, animals
in field exposures are of mixed
ages, and states of health, may be
living in less than optimum
environmental and nutritional
conditions, and are exposed to a
mixture of toxic agents by multiple
exposure routes. Exposures to
individual toxins maybe much lower
than those required to elicit an
adverse reaction in a small
controlled exposure group of ten
animals per dose group. The effects
from exposure may therefore not fit
neatly into the description given
for any single toxin, or the effects
from a particular species, of mold.
Few toxicological experiments
involving mycotoxins have been
performed using inhalation, the most
probable route for indoor exposures.
Defenses of there respiratory system
differ from those for ingestion (the
route for most mycotoxin
experiments). Experimental evidence
suggests the respiratory route to
produce more severe responses than
the digestive route (Cresia et
al.,1987). Effects from low level or
chronic low level exposures, or
ingestion exposures to mixtures of
mycotoxins, have generally not been
studied, and are unknown. Effects
from high level, acute sub-acute and
sub-chronic ingestion exposures to
single mycotoxins have been studied
for many of the mycotoxins isolated.
Other mycotoxins have only
information on cytotoxicity or in
vitro effects.
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