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A brief introduction to detection dogs
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Posted by Susan Lillard
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Tuesday, 29 April 2008
Detection Dogs
Handling and Training
Andy Falco
Falco K9 Academy
Detection dogs are some of the greatest tools we have to locate hidden substances, whether they’re narcotics, bombs, termites, incendiary mold or any other ODOR you have trained your dog to locate. However, one thing that can make a detection dog ineffective is a poor handler. This may or may not be news to you, but you must be aware of it or you are doomed to fail. You must also know that it is not necessarily my style to place “blame” on the handler for messing his dog up, but it is important to know the ways in which you could cause your dog to become or remain ineffective.
Selection of the Proper Dog
To ensure that you are working with a dog that has been properly selected, I first need to discuss what is essential in a detection dog. I’m sure that every handler believes his or her dog is one of the best, and was properly selected; however, I have taught at many seminars where the fact that a dog was not locating odor was not the fault of the handler…simply, the wrong dog was selected for the job.
Whether a dog is being trained with food or a toy, the most important thing is that he has a strong motivation for one or both. This desire must be natural, and not forced upon the dog. If you have to starve a dog in order to motivate him, that is not a natural desire for food; similarly, if you have to force his interest in retrieving a toy, the method is not going to work. The reward, whether food or toy, is the motivating factor that causes the dog to search for the odor/s we have imprinted on his brain, and desire for the reward should be the foremost thing on his mind. This motivator must be stronger than anything else that could prove distracting (animal smells, rodents, humans, etc). A dog who is easily distracted will almost always be a poor candidate for this work.
Next, and just as important, your dog must have a strong desire to hunt, meaning he will stay on task to find the one thing that he is seeking (in this case it is the food or toy he’s been trained with that has been linked to an odor). In some cases, dogs have a strong desire for food or a toy but will not hunt for it…these are the ones that go crazy when they see the toy in your hand or bouncing about on the ground (visual). They will chase and retrieve this toy as long as they see it, but as soon as it’s out of sight they stop and stare at you to throw another one, or want you to go find the “lost” toy. In other words, they have no desire to hunt for it. Other dogs may hunt for a short period of time and quit. What you need for detection work is one that never quits, or at least does not quit easily.
Some of the other traits you will (obviously) need in a dog:
• Healthy
• Trainable
• Courageous
• Sociable
• Confident
Working With the Dog’s Natural Talents
Every dog has a natural ability to hunt and detect what it wants. And I stated before, individuals respond on various levels to different motivators. The challenge for us is to train a dog to search for something that we want to find, such as an explosive. So, what we have to do is teach the dog that we are searching for something that he wants. Sometimes the problem is that we forget this and become emotional about it, or we begin to “force” the issue with the dog. Remember, it is natural for dogs to search for things that they want, so use this to your advantage.
Do your best not to get caught up in the emotion of “having to find something,” or in the pressure of the moment. Years ago, I was searching for narcotics in front of my administration at the Anaheim Police Department and the DEA; this was a huge case for the department, and I was told: Your dog has to find something. Naturally, a fantastic detection dog was then turned into an average dog that appeared to be untrained and had absolutely no ability to find anything! I had allowed myself to become emotional about the search, and the dog was confused and did not understand why I was acting so strangely. It is very true that your emotions go straight down the leash to the dog.
Therefore, you must do your best to work as you train and train as you work. This detection thing is simply a game and you both should enjoy doing it. If at any time it becomes work, or stressful for either one of you, your effectiveness will diminish or become nonexistent.
Your Role as the Handler
If your dog is properly selected, properly imprinted and properly trained, he should not need you. You are merely a taxi cab driver and facilitator in the searching process. I know this is hard for you as the leader of your pack, but in the case of running a detection dog you are going to be following the dog’s lead…in general. Now, don’t go crazy on me with this aspect, but you really are going to simply make sure that your dog gets to the search location, and then assist him in getting to the places he needs to be in order to have the highest probability of locating odor. The less you distract him and get in his way, the more successful you will be. You do not need to tell your dog to “seek, seek, seek, seek” endlessly, or point out search areas until he begins to ignore you. Save your motivation until you really need it to complete your search. I see and hear far too many handlers annoying their dogs and distracting them from the task at hand.
This philosophy goes back to the understanding that your detection dog has a natural ability to hunt, and truly wants to find the odor he has been trained to find. Over time and with proper training, the dog will learn where he needs to sniff in order to be successful; so, although you may occasionally need to point out a seam in a car or an electrical socket, over time and with proper training your dog will seek and locate things on his own. When you see this happen, you only need to say “Good Boy,” and move on. After a period of time you will only reinforce every so often, and eventually there will be a point when you barely speak to your dog at all. You will no longer need you to “help” him, you will only need to ensure that he goes to the places in your search area that he needs to go.
On Leash or Off Leash
Simply put, it depends, but you should train your dog to do both. I believe there is always a time for one or the other. You might go on 10 to 20 searches that require you to handle your dog on leash, and then you will get that one…or just the opposite. Your dog may have a preference at first, but that is why we have the philosophy at Falco K9 Academy to “Train what you are bad at…not always what you are good at.” Sometimes as humans we get into a rut, and we do what comes most easily. So, if you are struggling with your dog at doing off leash searches, then you probably should reduce the size of the search area and teach your dog how to search off leash.
Training off leash will help take you out of the picture when it comes to influencing your dog. With the leash we tend to communicate where the find is, or where we think it is. Sometimes we cannot help pulling up on the leash, or dropping it when we know the dog is close to a find. If your dog is good at off leash searching, you can stand back and simply watch. If you learn not to talk to your dog so much, you will not make the mistake of verbally queuing him, and he will learn to make the find on his own.
In training or working on leash, you have to be careful not to use the leash as a communication tool. It should be, in most cases, loose and only used to redirect the dog to a location that needs to be searched. Your hands needs to be soft on the leash, with the ability to move it in and out of your hand in order to prevent it from getting entangled or tight. Working the leash is an art, and it should ultimately be relaxed and natural.
Videotaping your Searches
Videoing your training and searches is a great tool for you and your dog’s effectiveness; this is the best way to see how you influence and help your dog make the find. It is extremely important that your dog shows you where the find is, and not the other way around.
As you watch the tape, look for some to the following:
• Changing your pace near the find
• Pulling or extending the leash near the find
• Dropping the leash near the find
• Changng the pitch of your voice near the find
• Constantly talk to your dog
• Forcing the dog through the search
• Getting in the dog’s way
• Missing changes in the dog’s body language when he is near the find
• Pulling your dog off finds
• Bending at your waist during the search and then standing up straight near the find
• Reaching for the reward near the find, before the dog shows interest or when the dog shows interest
• Dragging your feet near the find
• Look for any other changes in your behavior as you near the find
Do not worry about any video of your training being used against you in court. These videos are part of the training process, and will show that you are conscientious about improvement and are constantly in review of the effectiveness of you and your dog. As long as you are not abusive to your dog, or he never finds anything on the tape, you are only going to benefit from it in court; the opposition will not want the jury or judge seeing you doing effective training.
Summary
My hope for you as you read this is that you will become a better handler by becoming less involved in the search. This will allow for the dog to do the detecting, and for you to be the brains of the operation. As you become less involved in working the dog, your world will open up and you will see more of the search area, and actually see the sudden changes in your dog as he gets into and out of odor. By being less involved in pointing, blocking and whatever else you may think you need to be involved in, you are able to actually stand back and supervise. This means evaluating your search area with one eye, and watching your dog’s signals with the other. You will be amazed at what happens when you just allow your dog to work. Happy Hunting!
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Posted by Susan Lillard
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Monday, 28 April 2008
Mycotoxins List – Susan Lillard 1
Mycotoxin List
Susan Lillard
President of the Mold Help Organization
Some Common Mycotoxins
Mycotoxin Descriptions
Mycotoxins produced by indoor fungi
Molds can produce other secondary metabolites (see list in table below) such as
antibiotics and mycotoxins. Antibiotics are isolated from mold (and some bacterial)
cultures and some of their bacteriotoxic or bacteriostatic properties are exploited
medicinally to combat infections.
Mycotoxins are also products of secondary metabolism of molds. They are not essential
to maintaining the life of the mold cell in a primary way (at least in a friendly world),
such as obtaining energy or synthesizing structural components, informational molecules
or enzymes. They are products whose function seems to be to give molds a competitive
advantage over other mold species and bacteria. Mycotoxins are nearly all cytotoxic,
disrupting various cellular structures such as membranes, and interfering with vital
cellular processes such as protein, RNA and DNA synthesis. Of course they are also toxic
to the cells of higher plants and animals, including humans.
Mycotoxins vary in specificity and potency for their target cells, cell structures or cell
processes by species and strain of the mold that produces them. Higher organisms are
not specifically targeted by mycotoxins, but seem to be caught in the crossfire of the
biochemical warfare among mold species and molds and bacteria vying for the same
ecological niche.
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
Mycotoxins List – Susan Lillard Roberts 2
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 may be 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. Field exposures of animals
to molds (in contrast to controlled laboratory exposures) show effects on the immune
system as the lowest observed adverse effect. Such immune effects are manifested in
animals as increased susceptibility to infectious diseases (Jakab et al., 1994). It is
important to note that almost all mycotoxins have an immunosuppressive effect,
although the exact target within the immune system may differ. Many are also cytotoxic,
so that they have route of entry effects that may be damaging to the gut, the skin or the
lung. Such cytotoxicity may affect the physical defense mechanisms of the respiratory
tract, decreasing the ability of the airways to clear particulate contaminants (including
bacteria or viruses), or damage alveolar macrophages, thus preventing clearance of
contaminants from the deeper lung. The combined result of these activities is to increase
the susceptibility of the exposed person to infectious disease, and to reduce his defense
against other contaminants. They may also increase susceptibility to cancer.
Because indoor samples are usually comprised of a mixture of molds and their spores, it
has been suggested that a general test for cytotoxicity be applied to a total indoor
sample to assess the potential for hazard as a rough assessment (Gareis, 1995).
The following summary of toxins and their targets is adapted from Smith and Moss
(1985), with a few additions from the more recent literature. While this compilation of
effects does not describe the effects from multiple exposures, which could include
synergistic effects, it does give a better idea of possible results of mycotoxin exposure to
multiple molds indoors.
Vascular system (increased vascular fragility, hemorrhage into body tissues, or
from lung, e. g., aflatoxin, satratoxin, roridins).
Digestive system (diarrhea, vomiting, intestinal hemorrhage, liver effects, i. e.,
necrosis, fibrosis: aflatoxin; caustic effects on mucous membranes: T-2 toxin;
anorexia: vomitoxin.
Respiratory system: respiratory distress, bleeding from lungs e. g., trichothecenes.
Nervous system, tremors, incoordination, depression, headache, e. g.,
tremorgens, trichothecenes.
Cutaneous system: rash, burning sensation sloughing of skin, photosensitization,
e. g., trichothecenes.
Urinary system, nephrotoxicity, e. g. ochratoxin, citrinin.
Reproductive system; infertility, changes in reproductive cycles, e. g. T-2 toxin,
zearalenone.
Immune system: changes or suppression: many mycotoxins.
It should be noted that not all mold genera have been tested for toxins, nor have all
species within a genus necessarily been tested. Conditions for toxin production vary with
cell and diurnal and seasonal cycles and substrate on which the mold grows, and those
conditions created for laboratory culture may differ from those the mold encounters in its
environment. Toxicity can arise from exposure to mycotoxins via inhalation of mycotoxincontaining
mold spores or through skin contact with the toxigenic molds (Forgacs, 1972;
Mycotoxins List – Susan Lillard Roberts 3
Croft et al., 1986; Kemppainen et al., 1988 -1989). A number of toxigenic molds have
been found during indoor air quality investigations in different parts of the world. Among
the genera most frequently found in numbers exceeding levels that they reach outdoors
are Aspergillus, Penicillium, Stachybotrys, and Cladosporium (Burge, 1986; Smith et al.,
1992; Hirsh and Sosman, 1976; Verhoeff et al., 1992; Miller et al., 1988; Gravesen et
al., 1999).
Some Common Mycotoxins and the Organisms that Produce them
Mycotoxin Organism
Acetoxyscirpenediol Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. avenaceum, F. roseum, and F. nivale
Acetyldeoxynivalenol Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. avenaceum, F. roseum, and F. nivale
Acetylneosolaniol Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. avenaceum, F. roseum, and F. nivale
Acetyl T-2 toxin Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. avenaceum, F. roseum, and F. nivale
Aflatoxin Aspergillus flavus, A. parasiticus
Aflatrem Aspergillus flavus
Altenuic acid Alternaria alternata
Alternariol Alternaria alternata
Austdiol Aspergillus ustus
Austamide Aspergillus ustus
Austocystin Aspergillus ustus
Avenacein +1 Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. avenaceum, F. roseum, and F. nivale
Beauvericin +2 Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. avenaceum, F. roseum, and F. nivale
Bentenolide Monographella nivalis
Brevianamide Aspergillus ustus
Butenolide Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. avenaceum, F. roseum, and F. nivale
Calonectrin Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. avenaceum, F. roseum, and F. nivale
Chaetoglobosin Chaetomium globosum
Citrinin Aspergillus carneus, A. terreus, Penicillium citrinum, P.
hirsutum, P. verrucosum
Citreoviridin Aspergillus terreus, Penicillium citreoviride
Cochliodinol Chaetomium cochliodes
Crotocin Acremonium crotocinigenum
Cytochalasin E Aspergillus clavatus
Cyclopiazonic acid Aspergillus versicolor
Mycotoxins List – Susan Lillard Roberts 4
Deacetylcalonectrin Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. avenaceum, F. roseum, and F. nivale
Deoxynivalenol
diacetate
Fusarium moniliforme, and F. nivale
Deoxynivalenol
monoacetate
Fusarium moniliforme, F. culmorum, F. avenaceum, F.
roseum, and F. nivale
Diacetoxyscirpenol Fusarium moniliforme, F. equiseti
Destruxin B Aspergillus ochraceus
Enniatins Fusarium moniliforme, F. avenaceum, F. roseum, F.
solani, and F. nivale
Fructigenin +1 Fusarium moniliforme, F. culmorum, F. avenaceum, and
F. roseum
Fumagilin Aspergillus fumigatus
Fumonisin B1 Fusarium moniliforme, F. culmorum, F. avenaceum, and
F. nivale
Fusaric acid Fusarium moniliforme
Fusarin Fusarium moniliforme
Gliotoxin Alternaria, Aspergillus fumigatus, Penicillium
HT-2 toxin Fusarium moniliforme, F. culmorum, F. avenaceum, and
F. nivale
Ipomeanine Fusarium moniliforme, F. culmorum, F. avenaceum, and
F. nivale
Islanditoxin Penicillium islandicum
Lateritin +1 Fusarium moniliforme, F. culmorum, F. avenaceum, and
F. nivale
Lycomarasmin +1 Fusarium moniliforme
Malformin Aspergillus niger
Maltoryzine Aspergillus spp.
Moniliformin Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. avenaceum, F. roseum, and F. nivale
Monoacetoxyscirpenol Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. avenaceum, F. roseum, and F. nivale
Neosolaniol Fusarium moniliforme, F. solani, F. culmorum, F.
avenaceum, and F. roseum
Nivalenol Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. avenaceum, F. roseum, and F. nivale
NT-1 toxin Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. avenaceum, F. roseum, and F. nivale
NT-2 toxin Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. , F. solani, avenaceum, F. roseum, and F.
nivale
Ochratoxin Aspergillus ochraceus, Penicillium viridictum
Mycotoxins List – Susan Lillard Roberts 5
Oxalic acid Aspergillus niger
Patulin Aspergillus clavatus, Penicillium expansum, Botrytis, P.
roquefortii, P. claviforme, P. griseofulvum
Penicillic acid Aspergillus ochraceus
Penitrem Penicillium crustosum
Roridin E Myrothecium roridum, M. verrucaria, Dendrodochium spp.
, Cylindrocarpon spp. , Stachybotrys spp.
Rubratoxin Penicillium rubrum
Rubroskyrin Penicillium spp.
Rubrosulphin Penicillium viridicatum
Rugulosin Penicillium brunneum, P. kloeckeri, P. rugulosum
Sambucynin +1 Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. solani, F. avenaceum, F. roseum, and F.
nivale
Satratoxins, F,G,H Stachybotrys chartarum, Trichoderma viridi
Scirpentriol Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. solani, F. avenaceum, F. roseum, and F.
nivale
Slaframine Rhizoctonia leguminicola
Sterigmatocystin Aspergillus flavus, A. nidulans, A. versicolor, Penicillium
rugulosum
T-1 toxin Fusarium moniliforme, F. equiseti, F. culmorum, F.
solani, F. avenaceum, F. roseum, and F. nivale
T-2 toxin Fusarium moniliforme, F. equiseti, F. culmorum, F.
solani, F. avenaceum, F. roseum, and F. nivale
Triacetoxyscirpendiol Fusarium moniliforme, F. equiseti, F. avenaceum, F.
roseum, and F. nivale
Trichodermin Trichoderma viride
Trichothecin Trichothecium roseum
Trichoverrins Stachybotrys chartarum
Trichoverrols Stachybotrys chartarum
Tryptoquivalene Aspergillus clavatus
Verrucarin Myrothecium verrucaria, Dendrodochium spp. ,
Stachybotrys chartarum
Verruculogen Aspergillus fumigatus, Stachybotrys chartarum
Viopurpurin Trichophyton spp. , Penicillium viridicatum
Viomellein Aspergillus spp. , Penicillium aurantiogriseum, P.
crustosum, P. viridicatum
Viriditoxin Aspergillus fumigatus
Xanthocillin Eurotium chevalieri
Yavanicin+1 Fusarium culmorum, F. graminearum, F. oxysporum, F.
roseum, F. moniliforme, F. avenaceum, F. equiseti, and
Mycotoxins List – Susan Lillard Roberts 6
F. nivale
Zearalenone Fusarium culmorum, F. graminearum, F. oxysporum, F.
roseum, F. moniliforme, F. avenaceum, F. equiseti, and
F. nivale
Mycotoxin Organism
Acetoxyscirpenediol Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. avenaceum, F. roseum, and F. nivale
Acetyldeoxynivalenol Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. avenaceum, F. roseum, and F. nivale
Acetylneosolaniol Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. avenaceum, F. roseum, and F. nivale
Acetyl T-2 toxin Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. avenaceum, F. roseum, and F. nivale
Aflatoxin Aspergillus flavus, A. parasiticus
Aflatrem Aspergillus flavus
Altenuic acid Alternaria alternata
Alternariol Alternaria alternata
Austdiol Aspergillus ustus
Austamide Aspergillus ustus
Austocystin Aspergillus ustus
Avenacein +1 Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. avenaceum, F. roseum, and F. nivale
Beauvericin +2 Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. avenaceum, F. roseum, and F. nivale
Bentenolide Monographella nivalis
Brevianamide Aspergillus ustus
Butenolide Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. avenaceum, F. roseum, and F. nivale
Calonectrin Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. avenaceum, F. roseum, and F. nivale
Chaetoglobosin Chaetomium globosum
Citrinin Aspergillus carneus, A. terreus, Penicillium citrinum, P.
hirsutum, P. verrucosum
Citreoviridin Aspergillus terreus, Penicillium citreoviride
Cochliodinol Chaetomium cochliodes
Crotocin Acremonium crotocinigenum
Cytochalasin E Aspergillus clavatus
Cyclopiazonic acid Aspergillus versicolor
Deacetylcalonectrin Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. avenaceum, F. roseum, and F. nivale
Deoxynivalenol
diacetate
Fusarium moniliforme, and F. nivale
Mycotoxins List – Susan Lillard Roberts 7
Deoxynivalenol
monoacetate
Fusarium moniliforme, F. culmorum, F. avenaceum, F.
roseum, and F. nivale
Diacetoxyscirpenol Fusarium moniliforme, F. equiseti
Destruxin B Aspergillus ochraceus
Enniatins Fusarium moniliforme, F. avenaceum, F. roseum, F.
solani, and F. nivale
Fructigenin +1 Fusarium moniliforme, F. culmorum, F. avenaceum, and
F. roseum
Fumagilin Aspergillus fumigatus
Fumonisin B1 Fusarium moniliforme, F. culmorum, F. avenaceum, and
F. nivale
Fusaric acid Fusarium moniliforme
Fusarin Fusarium moniliforme
Gliotoxin Alternaria, Aspergillus fumigatus, Penicillium
HT-2 toxin Fusarium moniliforme, F. culmorum, F. avenaceum, and
F. nivale
Ipomeanine Fusarium moniliforme, F. culmorum, F. avenaceum, and
F. nivale
Islanditoxin Penicillium islandicum
Lateritin +1 Fusarium moniliforme, F. culmorum, F. avenaceum, and
F. nivale
Lycomarasmin +1 Fusarium moniliforme
Malformin Aspergillus niger
Maltoryzine Aspergillus spp.
Moniliformin Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. avenaceum, F. roseum, and F. nivale
Monoacetoxyscirpenol Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. avenaceum, F. roseum, and F. nivale
Neosolaniol Fusarium moniliforme, F. solani, F. culmorum, F.
avenaceum, and F. roseum
Nivalenol Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. avenaceum, F. roseum, and F. nivale
NT-1 toxin Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. avenaceum, F. roseum, and F. nivale
NT-2 toxin Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. , F. solani, avenaceum, F. roseum, and F.
nivale
Ochratoxin Aspergillus ochraceus, Penicillium viridictum
Oxalic acid Aspergillus niger
Patulin Aspergillus clavatus, Penicillium expansum, Botrytis, P.
roquefortii, P. claviforme, P. griseofulvum
Penicillic acid Aspergillus ochraceus
Mycotoxins List – Susan Lillard Roberts 8
Penitrem Penicillium crustosum
Roridin E Myrothecium roridum, M. verrucaria, Dendrodochium spp.
, Cylindrocarpon spp. , Stachybotrys spp.
Rubratoxin Penicillium rubrum
Rubroskyrin Penicillium spp.
Rubrosulphin Penicillium viridicatum
Rugulosin Penicillium brunneum, P. kloeckeri, P. rugulosum
Sambucynin +1 Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. solani, F. avenaceum, F. roseum, and F.
nivale
Satratoxins, F,G,H Stachybotrys chartarum, Trichoderma viridi
Scirpentriol Fusarium moniliforme, F. equiseti, F. oxysporum, F.
culmorum, F. solani, F. avenaceum, F. roseum, and F.
nivale
Slaframine Rhizoctonia leguminicola
Sterigmatocystin Aspergillus flavus, A. nidulans, A. versicolor, Penicillium
rugulosum
T-1 toxin Fusarium moniliforme, F. equiseti, F. culmorum, F.
solani, F. avenaceum, F. roseum, and F. nivale
T-2 toxin Fusarium moniliforme, F. equiseti, F. culmorum, F.
solani, F. avenaceum, F. roseum, and F. nivale
Triacetoxyscirpendiol Fusarium moniliforme, F. equiseti, F. avenaceum, F.
roseum, and F. nivale
Trichodermin Trichoderma viride
Trichothecin Trichothecium roseum
Trichoverrins Stachybotrys chartarum
Trichoverrols Stachybotrys chartarum
Tryptoquivalene Aspergillus clavatus
Verrucarin Myrothecium verrucaria, Dendrodochium spp. ,
Stachybotrys chartarum
Verruculogen Aspergillus fumigatus, Stachybotrys chartarum
Viopurpurin Trichophyton spp. , Penicillium viridicatum
Viomellein Aspergillus spp. , Penicillium aurantiogriseum, P.
crustosum, P. viridicatum
Viriditoxin Aspergillus fumigatus
Xanthocillin Eurotium chevalieri
Yavanicin+1 Fusarium culmorum, F. graminearum, F. oxysporum, F.
roseum, F. moniliforme, F. avenaceum, F. equiseti, and
F. nivale
Zearalenone Fusarium culmorum, F. graminearum, F. oxysporum, F.
roseum, F. moniliforme, F. avenaceum, F. equiseti, and
F. nivale
Mycotoxins List – Susan Lillard Roberts 9
Fungi are ubiquitous to the environment and primarily saprophytic, using nonliving
organic material as a nutrient source for growth and reproduction. Many of these
saprophytes can colonize organic water-damaged building materials. During the digestion
process fungi secrete enzymes into the nutrient source to break down complex
compounds into simpler compounds, which are taken up by the fungi and digested. The
digested nutrients are classified into two categories, primary and secondary metabolites.
The primary metabolites consist of cellulose and other compounds that are used for
energy to grow and reproduce.
The secondary metabolites, called mycotoxins, are produced to give fungi a competitive
edge against other microorganisms, including other fungi. There are over 200 recognized
mycotoxins, however, the study of mycotoxins and their health effects on humans is in
its infancy and many more are waiting to be discovered. Many mycotoxins are harmful to
humans and animals when inhaled, ingested or brought into contact with human skin.
Mycotoxins can cause a variety of short term as well as long-term health effects, ranging
from immediate toxic response to potential long-term carcinogenic and teratogenic
effects. Symptoms due to exposure to mycotoxins include dermatitis, cold and flu
symptoms, sore throat, headache, fatigue, diarrhea, and impaired or altered immune
function, which may lead to opportunistic infection. Historically, mycotoxins have been a
persistent problem to farmers and the animal husbandry industry in Eastern Europe and
developing countries. Mycotoxins are a known agent in biological warfare as a moderate
illness compared to the other biologicals.
Recently, however, research has implicated many toxin-producing fungi, such as
Stachybotrys, Penicillium, Aspergillus and Fusarium species, to indoor air quality
problems and building related illnesses. Inhalation of mycotoxin producing fungi in
contaminated buildings is the most significant exposure, however, dermal contact from
handling contaminated materials and the chance of ingesting toxin containing spores
through eating, drinking and smoking is likely to increase exposure in a contaminated
environment. Recent advances in technology have given laboratories the ability to test
for specific mycotoxins without employing cost-prohibitive gas chromatography or high
performance liquid chromatography techniques. Currently, surface, bulk, food and feeds,
and air samples can be analyzed relatively inexpensively for the following mycotoxins:
Aflatoxin
Aflatoxin is one of the most potent carcinogens known to man and has been linked to
a wide variety of human health problems. The FDA has established maximum
allowable levels of total aflatoxin in food commodities at 20 parts per billion. The
maximum level for milk products is even lower at 0.5 parts per billion. Primarily
Aspergillus species fungi produce aflatoxin.
Ochratoxin
Ochratoxin is primarily produced by species of Penicillium and Aspergillus.
Ochratoxin is damaging to the kidneys and liver and is also a suspected carcinogen.
There is also evidence that it impairs the immune system.
T-2 Toxin
Mycotoxins List – Susan Lillard Roberts 10
T-2 Toxin is a tricothecene produced by species of Fusarium and is one of the more
deadly toxins. If ingested in sufficient quantity, T-2 toxin can severely damage the
entire digestive tract and cause rapid death due to internal hemorrhage. T-2 has
been implicated in the human diseases alimentary toxic aleukia and pulmonary
hemosiderosis. Damage caused by T-2 toxin is often permanent.
Fumonisin
Fumonisin is a toxin associated with species of Fusarium. Fumonisin is commonly
found in corn and corn-based products, with recent outbreaks of veterinary
mycotoxicosis occurring in Arizona, Indiana, Kentucky, North Carolina, South
Carolina, Texas and Virginia. The animals most affected were horses and swine,
resulting in dozens of deaths. Fumonisin toxin causes "crazy horse disease", or
leukoencephalomalcia, a liquefaction of the brain. Symptoms include blindness, head
butting and pressing, constant circling and ataxia, followed by death. Chronic lowlevel
exposure in humans has been linked to esophageal cancer. The American
Association of Veterinary Laboratory Diagnosticians (AAVLD) advisory levels for
fumonisin in horse feed is 5 ppm.
Vomitoxin or Deoxynivalenol(DON)
Vomitoxin, chemically known as Deoxynivalenol, a tricothecene mycotoxin, is
produced by several species of Fusarium. Vomitoxin has been associated with
outbreaks of acute gastrointestinal illness in humans. The FDA advisory level for
vomitoxin for human consumption is 1 ppm.
Zearalenone
Zearalenone is also a mycotoxin produced by Fusarium molds. Zearalenone toxin is
similar in chemical structure to the female sex hormone estrogen and targets the
reproductive organs.
Other mycotoxins of clinical significance are as follows:
Citrinin
Citrinin is a nephrotoxin produced by Penicillium and Aspergillus species. Renal
damage, vasodilatation, and bronchial constriction are some of the health effects
associated with this toxin.
Alternariol
Alternariol cytotoxic compound derived from Alternaria alternata
Satratoxin H
Satratoxin H is a macrocyclic tricothecene produced by Stachybotrys chartarum,
Trichoderma viridi and other fungi. High doses or chronic low doses are lethal. This
toxin is abortogenic in animals and is believed to alter immune system function and
makes affected individuals more susceptible to opportunistic infection.
Mycotoxins List – Susan Lillard Roberts 11
Gliotoxin
Gliotoxin is an immunosuppressive toxin produced by species of Alternaria,
Penicillium and Aspergillus.
Patulin
Patulin is a mycotoxin produced by Penicillium, Aspergillus and a number of other
genera of fungi. It is believed to cause hemorrhaging in the brain and lungs and is
usually associated with apple and grape spoilage.
Sterigmatocystin
Sterigmatocystin is a nephrotoxin and a hepatotoxin produced by Aspergillus
versicolor . This toxin is also considered to be carcinogenic. Other mycotoxins include
- Penicillic acid, roquefortine, cyclopiazonic acid, verrucosidin, rubratoxins A and B,
PR toxin, luteoskyrin, cychlochlorotine, rugulosin, erythroskyrine, secalonic acid D,
viridicatumtoxin, kojic acid, xanthomegnin, viomellein, chaetoglobosin C, echinulin,
flavoglaucin, versicolorin A, austamide, maltoyzine, aspergillic acid, paspaline,
aflatrem, fumagillin nigragillin chlamydosporol, isotrichodermin and many more.
As discussed there are many mycotoxins that can cause adverse health effects and
even death in humans. The synergistic effect of exposure to multiple mycotoxins
simultaneously is very poorly understood. Even more poorly understood are the byproducts
of mycotoxin degradation, particularly under the influence of strong
oxidizing agents such as sodium hypochlorite and/or ozone, agents frequently used
or misused by remediation personnel in the industry. More research is required in
this field to better understand the relationship of fungal contamination, mycotoxin
production on building substrates and building related disease.
Endotoxins
Endotoxin is the name given to a group of heat stabile lipopolysaccharide molecules
present in the cell walls of gram-negative bacteria that have a certain characteristic
toxic effect. The lipid portion of each molecule is responsible for its toxicity and can
vary between bacterial species and even from cell to cell. When inhaled, endotoxin
creates an inflammatory response in humans that may result in fever, malaise,
alterations in white blood cell counts, headache, respiratory distress and even death.
It is common to the environment due to the ubiquitous nature of Gram-negative
bacteria. Exposure to elevated levels of endotoxin primarily occurs through exposure
to aerosols from specific reservoirs such as cotton mills, wastewater treatment
facilities, air washers, humidifiers and any other occupational settings where Gramnegative
bacteria can flourish.
Mycotoxins
In addition to their roles as irritants and allergens, many fungi produce toxic
chemical constituents (Kendrick, 1992; Miller, 1992; Wyllie and Morehouse, 1977).
Mycotoxins List – Susan Lillard Roberts 12
Samson and co-workers (1996) defined mycotoxins as "fungal secondary metabolites
that in small concentrations are toxic to vertebrates and other animals when
introduced via a natural route". These compounds are non-volatile and may be
sequestered in spores and vegetative mycelium or secreted into the growth
substrate. The mechanism of toxicity of many mycotoxins involves interference with
various aspects of cell metabolism, producing neurotoxic, carcinogenic or teratogenic
effects (Rylander, 1999). Other toxic fungal metabolites such as the cyclosporins
exert potent and specific toxicity on the cellular immune system ( | |
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