Mold:
What is it?
Mold is a microscopic organism that grows
from spores. There are estimated to be over 100,000 species of mold in the
World and they are virtually everywhere in our environment. They are usually inactive
and don't present problems. In fact, molds are part of the natural environment
and play a part in nature by breaking down dead organic matter such as fallen
leaves and dead trees. However, indoors, mold growth should be avoided. When it
settles on a surface under the right moisture and temperature conditions they
start to swell and begin to germinate and multiply (colonize).
Certain types of molds are capable of producing a class of
compounds called mycotoxins. Identifying mold is important because
it is a common cause of asthma and/or allergic reaction with sensitized people.
For these people, exposure to molds can cause symptoms such as nasal
stuffiness, eye irritation, wheezing, or skin irritation. Some people, such as
those with serious allergies to molds, may have more severe reactions such as
memory loss or severe lung problems. It's thought that mycotoxins are more
likely to trigger health problems in even healthy individuals.
Mold Basics:
No Hype, Just Facts.
WHY IS MOLD GROWING IN MY HOME?
Molds are part of the natural environment. Outdoors, molds play a part in
nature by breaking down dead organic matter such as fallen leaves and dead
trees, but indoors, mold growth should be avoided. Molds reproduce by means of
tiny spores; the spores are invisible to the naked eye and float through
outdoor and indoor air. Mold may begin growing indoors when mold spores land on
surfaces that are wet. There are many types of mold, and none of them will grow
without water or moisture.
CAN MOLD CAUSE HEALTH PROBLEMS?
Molds are usually not a problem indoors, unless there is a source
of mold spores in an area where aerosolitation and human exposure can occur.
Molds have the potential to cause health problems. Molds produce allergens
(substances that can cause allergic reactions), irritants, and in some cases,
potentially toxic substances (mycotoxins). Allergic responses include hay
fever-type symptoms, such as sneezing, runny nose, red eyes, and skin rash
(dermatitis). Allergic reactions to mold are common. They can be immediate or
delayed. Molds can also cause asthma attacks in people with asthma who are
allergic to mold. Research on mold and health effects is ongoing. This provides
a brief overview; it does not describe all potential health effects related to
mold exposure. For more detailed information consult a health professional. You
may also wish to consult your state or local health department.
HOW DO I GET RID OF
MOLD?
It is impossible to get rid of all mold and mold spores indoors;
some mold spores will be found floating through the air and in house dust. The
mold spores will not grow if moisture is not present. Indoor mold growth can
and should be prevented or controlled by controlling moisture indoors. If there
is mold growth in your home, you must clean up the mold and fix the water
problem. If you clean up the mold, but don't fix the water problem, then, most
likely, the mold problem will come back.
Source:
Environmental Protection Agency
Mold Allergies
Along with pollens from trees, grasses, and weeds, molds are an
important cause of seasonal allergic rhinitis. People allergic to molds may
have symptoms from spring to late fall. The mold season often peaks from July
to late summer. Unlike pollens, molds may persist after the first killing frost.
Some can grow at subfreezing temperatures, but most become dormant. Snow cover
lowers the outdoor mold count dramatically but does not kill molds. After the
spring thaw, molds thrive on the vegetation that has been killed by the winter
cold.
WHAT IS MOLD ALLERGY?
When inhaled, microscopic fungal spores or, sometimes, fragments
of fungi may cause allergic rhinitis. Because they are so small, mold spores
may evade the protective mechanisms of the nose and upper respiratory tract to
reach the lungs.
In a small number of people, symptoms of mold allergy may be
brought on or worsened by eating certain foods, such as cheeses, processed with
fungi. Occasionally, mushrooms, dried fruits, and foods containing yeast, soy
sauce, or vinegar will produce allergic symptoms. There is no known
relationship, however, between a respiratory allergy to the mold Penicillium and
an allergy to the drug penicillin, made from the mold.
WHERE DO MOLDS GROW?
Molds can be found wherever there is moisture, oxygen, and a
source of the few other chemicals they need. In the fall they grow on rotting
logs and fallen leaves, especially in moist, shady areas. In gardens,they can
be found in compost piles and on certain grasses and weeds. Some molds attach
to grains such as wheat, oats, barley, and corn, making farms, grain bins, and
silos likely places to find mold.
WHICH MOLDS ARE ALLERGENIC?
In general, Alternaria and Cladosporium (Hormodendrum)
are the molds most commonly found both indoors and outdoors throughout the
United States. Aspergillus, Penicillium, Helminthosporium, Epicoccum,
Fusarium, Mucor, Rhizopus, and Aureobasidium (Pullularia)
are also common.
ARE MOLD COUNTS HELPFUL?
Similar to pollen counts, mold testing can suggest the types and
relative quantities of fungi present. Many of the common allergenic molds are
of the dry spore type--they release their spores during dry, windy weather.
Other fungi need high humidity, fog, or dew to release their spores.
In addition to the effect of day-to-day weather changes on mold
counts, spore populations may also differ between day and night. Day favors
dispersal by dry spore types and night favors wet spore types.
ARE THERE OTHER MOLD-RELATED DISORDERS?
Fungi or microorganisms related to them may cause other health
problems similar to allergic diseases. Some kinds of Aspergillus may
grasp the opportunity to invade the lungs or the whole body and may cause
several different illnesses, including both infections and allergy. These fungi
may lodge in the airways or a distant part of the lung and grow until they form
a compact sphere known as a "fungus ball." In people with lung damage
or serious underlying illnesses,
In some individuals, exposure to these fungi also can lead to
asthma or to a lung disease resembling severe inflammatory asthma called
allergic bronchopulmonary - aspergillosis. This latter condition, which
occurs only in a minority of people with asthma, is characterized by wheezing,
low-grade fever, and coughing up of brown-flecked masses or mucus plugs. Skin
testing, blood tests, X-rays, and examination of the sputum for fungi can help
establish the diagnosis. Corticosteroid drugs are usually effective in treating
this reaction; immunotherapy (allergy shots) is not helpful.
