Common Mold Types found in Southern California
Often “fungus” and “mold” are confusing as terms as they are sometimes used interchangeably. “Fungus” is a more general term. Fungi include molds, yeasts and macro-fungi like mushrooms, puffballs, etc.
Water damage inside your home or office whether known or unknown can result in mold growth. Exposure to molds particularly chronically can result in health symptoms. Reactions can vary widely from person to person. There are certain mold types that are commonly found due to water intrusion into building envelopes. We will be featuring some of the most common experienced in
Southern California. With the advent of El Nino, this seems the
opportune time for dealing with this subject.
Penicillium – What is it?
Penicillium is best known as the mold type that gave birth to the first of the antibiotics, Penicillin. In microscopic analysis, Penicillium is often grouped with Aspergillus. That grouping is generally shown as Penicillium/Aspergillus or Pen/Asp. The reason for this grouping is that the two spore types cannot be distinguished one from the other microscopically. To differentiate the two requires seeing the underlying structure which often means culturing (or growing) the organism.
Penicillium is found under normal conditions in soil, decaying plant debris, compost piles, and fruit rot. One species has even been detected in diesel fuel.
Indoors Penicillium will grow on a wide variety of materials (substrates) including building materials, fabrics, as well as a wide variety of foodstuffs, herbs and spices. The green mold often seen on oranges is likely Penicillium. Colors range in various shades of blue, green and white.
In air conditioning systems Penicillium can often be detected on cooling coils and/or interior fiberglass liner. On building materials Penicillium is one of the first or primary invaders along with Aspergillus. Both can produce toxins for the purpose of discouraging other molds invading space they have already claimed. It is speculated that some of these toxins could be harmful to humans, but this has never been clinically established. The primary invaders can be joined by a secondary invader, usually Cladosporium. With a continuation of high levels of moisture, they can be overgrown by Stachybotrys or possibly Chaetomium.
Industrial uses include cultures to help produce some cheeses, salami and sausages. Its most well known industrial use is of course the production of antimicrobial Penicillin.
Most people think that the antibiotic effects of Penicillium were first discovered in 1928 by Sir Alexander Fleming, but there is a much longer history about the use of molds for medicinal purposes. The history goes as far back into the BC times. There is evidence that the ancient Egyptian, Greeks, and Indians had medical uses for molds. Uses of molds and concoctions including molds were used to combat infections in various places in
Europe from the 16th
through the 19th centuries.
Reportedly the antibacterial properties were noticed and investigated as
early as 1871. This was during the
period while Joseph Lister, English surgeon, famed for promoting antiseptic
medicine, was improving medical treatment.
Even Louis Pasteur observed in 1877 that a Penicillium strain inhibited the growth of the Anthrax bacilli.
Never-the-less, it did take the organizational efforts of Dr. Fleming, after an accidental discovery to bring penicillin to the fore establishing it as a wonder drug. Returning from a vacation in September of 1928, he found Petri dishes of Staphylococcus aureus (a bacterium) contaminated with Penicillium notatum. This contamination prevented the normal growth of the Stephylococci. This accidental discovery totally changed medical history.
As Dr. Fleming famously wrote about that red-letter date, “When I woke up just after dawn on September 28, 1928, I certainly didn’t plan to revolutionize all medicine by discovering the world’s first antibiotic, or bacteria killer. But I guess that was exactly what I did.”
What’s the harm?
Many people are allergic to Penicillin. Being so allergic myself and due to some family history, I am acutely aware of this situation. My mother’s brother, whom I never met, died at a time when Penicillin was considered a miracle drug that could cure virtually anything. He had a minor illness and was given Penicillin to treat it. He got worse and developed a rash. He was given more Penicillin and got worse. They continued to increase the dosage until he died. He was one of the first documented cases of a patient dying of Penicillin allergy.
While certain individuals can develop allergies to virtually any mold, research shows that Penicillium species are known to cause a number of specific allergies. Some of the more familiar health effects related to Penicillium include asthma and hay fever. Some allergies have names that are specific to certain professions or activities. Some of these are: Cheese washer’s lung, Woodman’s lung, and Moldy wall hypersensitivity.
There is a species of Penicillium that can cause infection in humans, but it has not been found in the
. United States
Penicillium is a very common mold type around the world. Its metabolites form a microbial volatile organic compound (MVOC) that produces a heavy musty odor.
What can be done about it?
The most effective way to deal with mold is to prevent water from entering the building envelope. Given that this is impossible sometimes as leaks can occur no matter what you do, but be aware of potential roof leaks as well as leaking from plumbing fixtures. Preventative steps should be taken, so look and take necessary action.
Also remember that exterior walls are not equipped to sustain prolonged direct impact of water. That can break down the moisture shield causing water intrusion into wall cavities. This can happen due to sprinkler water spraying directly onto the wall, but it can also occur due to prolonged rainy periods with wind causing impact on a particular wall.
Once water intrusion does occur, remedies need to be applied as soon as possible. The source of the water must be determined and eliminated at the source as possible.
Once water intrusion does occur, remedies need to be applied as soon as possible. The source of the water must be determined and eliminated at the source as possible. During very heavy rains, wind driven rain water impacting on a wall might require a barrier to limit that impact.
Mold contamination of gypsum wallboard should be removed by a professional mold remediation company. The process includes isolating the affected area with plastic sheeting and putting it under negative air pressure to keep from disseminating mold spores to other parts of the building. Workers should wear appropriate personal protective equipment. All moldy material should be removed and disposed of. Air scrubbing should be done to remove residual mold spores. The interior of the remediation area should be HEPA (High Efficiency Particulate Arresting) filter vacuumed and wiped down. It would be best to have the area professionally inspected and tested prior to removal of the containment material.