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The Mould Ulocladium

Ulocladium is a widely distributed mould commonly found in soil and decaying plants. It has also been isolated from paper, textiles, dung, emulsion paint, grasses, fibres and wood. In indoor environment, Ulocladium has been found on painted surfaces, damp wall finished with wallpaper or water based emulsion paint; floor and mattress dust.

Conidiophores and spores of Ulocladium spUlocladium has two known species; Ulocladium chartarum and Ulocladium botrytis. Ulocladium chartarum is the species most commonly found in indoor environment. Presence of Ulocladium in indoor environment together with other moulds such as Stachybotrys, Fusarium and Chaetomium is an indication of water damage.

Ulocladium has been reported to cause Type I (hay fever) allergy. There have been cases of Ulocladium chartarum causing skin surface and deep skin infections in immuno-suppressed patients. Ulocladium botrytis has no proven pathogenicity.

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Are Mould Related Illnesses Real Or Imagined?

Mould associated illnesses have been explained by some experts as hysteria, describing the mould situation as a hoax that begin in the 1970’s following several cases of legionellosis (Legionnaires’ Disease) caused by the bacterium Legionella pneumophila. The media, including the internet have been blamed for highlighting claims of building related illnesses and hence fanning the hysteria. There might be some truth in this which, however, does not mean mould is harmless.

While it is true, some of the illnesses cannot be attributed to mould exposure for lack of scientific data or even by any logical reasoning, there is enough evidence, though in some cases circumstantial to support claims of mould related illnesses. Reactions of human beings from mould exposure differ from one individual to another. While majority of the population may not have problems with common indoor moulds, a certain percentage will react and show symptoms of mould related illnesses when exposed to mould.

As someone who identifies moulds, I have found myself developing an instant running nose when I inhale spores and odours of certain strains of Penicillium spp.

In my opinion, the extremists (those who attribute any imaginable illness to indoor mould exposure and those who believe mould has nothing to do with any building related illness) have not helped the public to understand the truth about mould.

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The Moulds Paecilomyces spp: How Do They Affect Our Lives?

Paecilomyces species are common environmental moulds. They are widespread in soils, composts, and food products. In indoor environment, Paecilomyces species have been isolated from air, damp walls, wet plaster work, carpet dust and HVAC fans.

Paecilomyces species are rarely associated with human infections but some species such as Paecilomyces variotii, Paecilomyces marquandii and Paecilomyces lilacinus are emerging as causative agents of mycoses in immuno-compromised patients.

Conidiophores and spores of Paecilomyces marquandiiSeveral species of Paecilomyces are important as agents of biological control. These include:

  1. Paecilomyces carneus
    Paecilomyces carneus is found on a wide range of material, and especially from soil. It is sometimes isolated from insects, though it appears to be a weak insect pathogen. Some isolates produce several metabolites of the antibiotic group cephalosporins.
  2. Paecilomyces farinosus
    Paecilomyces farinosus is also commonly isolated from soil. It is a well-known insect pathogen, and there has been interest in its use as an agent of biological control.
  3. Paecilomyces fumosoroseus
    Paecilomyces fumosoroseus has been isolated from soil, butter and gelatine. It is an insect parasite, causing economic damage to silkwork production in eastern Asia.
  4. Paecilomyces lilacinus
    Paecilomyces lilacinus is most commonly encountered in isolations from soil but has been found on insects on numerous occasions. It has also been found on various organic substrates including plastic contact lenses, synthetic rubber and polyurethane, and is used in fungus resistance testing. Paecilomyces lilacinus has been implicated as a human and animal pathogen.

 

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Indoor Mould: What are Mould Spores?

Chaetomium and Penicillium/Aspergillus spores from indoor airMould spores are tiny structures produced by moulds for the purpose of propagation. The term spore is general. There specific terms used for spores depending on how they are produced or the group of fungi producing them. Ascospores for example are spores produced by a group of fungi called Ascomycetes while Basidiospores are spores produced by Basidiomycetes which include the mushrooms.

How would spores affect human health?
Spores are tiny (range between 2-100 micrometers) and therefore are easily inhaled into the lungs. Susceptible individuals react to the protein component of the cell wall of the spores. Some moulds such as Aspergillus fumigatus may also grow in the lungs causing what is referred to as Aspergillosis.

How would you tell if you are inhaling potentially harmful levels of spore concentration?
The way to tell if occupants of a building were inhaling potentially harmful levels of spore concentration is to take air samples. Air may be taken to be analysed by culture methods or by direct microscopic examination. Culture methods may significantly underestimate the total airborne mould concentration in the air because only the viable spores or fragments of the mould can be detected in culture. The spores/fragments may also not be detected if the media used for culturing were not suitable for the types of moulds present in the air. Samples taken for direct microscopic examination (also referred to as non-viable air samples) allow the analyst to count all the spores and fragments regardless of whether the spores were viable or dead. Since susceptible individuals can also react to dead spores, non-viable samples would be the best to give an idea of whether occupants were inhaling potentially hazardous levels of mould spores.

Ulocladium and Stachybotrys spores from indoor airThe pictures show spores trapped from highly contaminated indoor air. The first picture shows spores of Chaetomium and Aspergillus/Penicillium. The second photo shows Ulocladium spores and Stachybotrys spores. Chaetomium, Stachybotrys and Ulocladium species are indicators of serious water damage. Spores of these moulds and those of Aspergillus and Penicillium pose inhalation risk.

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The Mould Wallemia sebi

Wallemia sebi is one of the so called xerophilic moulds, meaning that it can grow under relatively dry conditions (i.e., low water activity). Wallemia sebi has a world-wide distribution. It is common in indoor environment and has been isolated from jams, dates, bread, cakes, salted beans and fish, bacon, fruits, soil, hay, and textiles. It is also common in agricultural environments where it is suspected to be one of the causes of farmer’s lung disease and other human allergies.

Wallemia sebi also produces a mycotoxin called walleminol A. Not much is know about the health effects of this toxin to humans in indoor environment.

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Salmonella food poisoning and symptoms

Salmonella food poisoning has been a growing concern in recent news. It has frequently lead to recalls of beef, salads and organic products and, even peanut butter products. Salmonella food poisoning occurs when one eats raw or undercooked foods such meat, poultry, eggs or egg products. Properly cooked food can get contaminated with Salmonella if […]

Legionella pneumophila – Guidelines for Laboratory Interpretation

Legionella pneumophila is a Gram negative, aerobic bacteria that is characterized as an opportunistic pathogen. It is the cause of Legionnaires’ Disease, a severe form of pneumonia and, it is the cause of Pontiac fever, a non-pneumonic form of L. pneumophila infection. Legionella spp.’s mode of transmission is through aerosols or aspiration of contaminated water. The Public Health […]

The Indoor Mold Is An Early Warning Device

The mold (or mould, in the Queen’s English) has been the victim of a bad press. Mention the word and it conjures up an image of something rotting or in the process of decomposition. And yet, were it not for the mold that inspired the discovery of penicillin millions of lives would have been lost. […]