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Mycotoxins
and Disease: A key, but scientifically flawed new paper for proving plaintiff
cases
By
Dr. Ronald E. Gots, MD, PhD
A recent study
by Croft et al ("Clinical Confirmation of Trichothecene Mycotoxicosis
in Patient Urine," Journal of Environmental Biology. Vol.
23 (3), 2002, pp 301-320) appears, on its surface, to provide compelling
scientific evidence of inhalational mycotoxin disease in individuals residing
in contaminated residences. It also strongly argues that urine tests for
trichothecene mycotoxins are the new gold standard for assessing causation
and linking symptoms or diseases to indoor environments. This extensive
study, replete with citations, experimental elements and, ultimately,
far-reaching interpretations is both dramatic and highly useful for plaintiff
claims. The problem is that this study is so replete with fundamental
scientific and methodological errors that its conclusions range from speculations,
to sheer nonsense. A brief overview of this very important study will
be provided here. A more complete review of its fatal scientific flaws
will be discussed in subsequent reports. This is a study which must be
throughly understood by attorneysplaintiff and defensewho deal with mold-related
personal injury claims.
Dr. Croft, a veterinarian, is the lead author. He describes four cases
of individuals in detail and hundreds of others from an apartment complex,
allegedly living in mold-contaminated environments, who purportedly fit
the diagnosis of trichothecene mycotoxicosis. Using a variety of tests
(including an unusual skin patch test) and urine extraction of alleged
trichothecenes, he confirms exposure. Injecting rats with the urine extract
produces similar disorders further supporting his claims. A described
autopsy of a deceased subject adds to the impact of his claims.
This paper appears to the non-scientist to be a careful, thorough study.
Its conclusions seem strong and well-founded. Every disease and symptom
from aneurysms to pancreatic and prostate cancer through every one of
at least fifty symptoms, are claimed to arise from trichothecene intoxication.
Notwithstanding its peer-reviewed status and seeming validity, its flaws
are so manifest that they will require careful dissection in reports to
follow. A few key errors include:
No controls;
A claim, but no valid confirmation, of mycotoxin presence in the urine
or the bloodstream;
The use of novel, ill-supported tests
Attribution of every imaginable symptom and disease to the alleged exposure,
with no consideration of other far more likely, alternate causes;
Failure to consider normal dietary sources of trichothecenes;
There are many more.
Further analysis will follow in subsequent reports.
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Further
Review of "Clinical Confirmation of Trichothecene Mycotoxicosis in
Patient Urine,"
By Dr. Ronald E. Gots, MD, PhD
This is a further discussion of the paper by Croft, et al, ("Clinical
Confirmation of Trichothecene Mycotoxicosis in Patient Urine," Journal
of Environmtl. Biology, 23(3) 301-320 (2002)). In this paper, Croft
and his group (hereinafter, "Croft") claim to establish through
various scientific tests mycotoxicosis that is caused in humans through
exposure to mold-contaminated housing.
I have chosen a few key areas to focus upon in this analysis, which is,
by no means, an exhaustive review of the paper. Croft's paper is
replete with overstatements, mischaracterizations, experimental design
flaws and misuse of citations allegedly supporting the authors' methodologies.
These points are sufficient to call into doubt all of the claims in this
paper. Having now reviewed all of the articles cited by the authors, I
shall summarize a few critical findings.
The authors cite Ueno (1977, 1980, 1983) for their historical discussion
of the manifestations of trichothecene mycotoxicosis. In none of Ueno's
papers were the descriptions of illnesses comparable to those described
by Croft. For example, in Ueno (1977), specific illnesses associated
with specific mycotoxins were described. The toxicological features of
mycotoxis-induced illnesses are dependent upon the specific mycotoxin
and the species of animal affected. Ueno characterized some of these distinctive
disorders by their source, others by their clinical characteristics, e.g.,
B Alimentary toxic aleukia (ATA), moldy corn toxicosis, bean hull toxicosis,
stachybotrytoxicosis and others.
Contrary to Croft's assertion, T-2 toxin is primarily eliminated via the
GI tract and found in the feces. A smaller amount is found in the urine.
The metabolic pathways by which mycotoxins are handled in the body vary
among animal species. Since human metabolism is less well described than
is animal, we are not currently in a position to make blanket statements
about the metabolic processes that relate to T-2 toxin.
Croft asserts in his paper that certain urine extraction methods precipitate
trichothecenes. This note is unreferenced and cannot be checked.
Further, Croft claims that tests conducted on human urine indicate substantial
corollaries to the same tests already observed using animal urine. This
suggests that urinalysis confirms diagnoses in humans. These claims are
not referenced, therefore, the methodology, which is certainly not a generally
established practice, cannot be assessed or verified. Any conclusions
based on this methodology are neither valid nor reliable, notwithstanding
the claims made in this paper.
Croft attempts to use Koch's postulate, the generally-accepted scientific
standard for determining the presence of a pathogen and its cause of an
illness, to establish that mycotoxicosis is caused by mold exposure. Croft's
characterization of Koch's postulates, however, is entirely erroneous.
Moreover, he does not adhere to any of them in his scientific investigations.
These investigators have presented no objective, confirmatory data, only
conclusory statements, that they have extracted trichothecenes from these
patients' urines. They then say that "reproducing" the disease
in animals proved that the trichothecenes were causal. First, we have
no confirmation of trichothecene extraction. Second, considering the generalized
symptoms and "diseases" described in these patients, one wonders
what is meant by "the disease."
In the patient discussions, exposures are never established, merely assumed.
Temporal relationships between exposures and diseases varied from several
months to twelve years. The medical descriptions of these patients are
discussed in a fashion so sophomoric that they sound more like Reader's
Digest than a clinical paper description. Notably, there is no mention
of the diagnoses provided by treating physicians. This is particularly
notable in Case 4, in which the pathologic features of a devastating encephalomyelopathy
were identified. There are dozens of diseases known: mycotoxicosis is
not one of them.
Croft erroneously cited a test and misused a skin patch test upon which
the investigators relied heavily. The patch test for "alcohol dehydrogenase"
(Higuchi et al) supposedly measured an enzyme affected by mycotoxins.
First, there is no established basis for the assumption that "mycotoxins"
affect alcohol dehydrogenase. Second, the Hibachi letter (it is a Letter-to-an-Editor,
not a peer-reviewed study) was designed to test Asians, a significant
proportion of whom have an inherited deficiency in aldehyde (not alcohol,
as Croft stated) dehydrogenase which makes them intolerant to alcohol.
Croft somehow assumed that a positive test in their subjects reflected
mycotoxin effect, an effect which is medically unknown. Even assuming
that this skin test was positive (Croft got the enzyme wrong), it could
well have suggested an inherited defect as noted by the authors they cited.
Finally, Croft went far beyond the test protocol of the cited author.
They used a different method and a different scoring system, protocols
which have not been validated. Nevertheless, they use this test extensively,
suggesting that it quantified the extent of toxicity: a misleading, unwarranted
suggestion.
Another important component of Croft's "study" involved the
alleged extraction of trichothecenes from urine. They give no references
for their method and there is little reason to believe that trichothecenes
were extracted. Their conclusory statement that this was tested by thin
layer chromatography is neither properly discussed nor convincing. This
is particularly so when they say that TLC was consistent with those reported
for trichothecenes, but which of the trichothecenes? Each comes out at
a different place on TLC.
SPECT scans were used to demonstrate "neurotoxicity" by these
authors, yet such scans have little value for that purpose. A consensus
document and review articles by the Neuroimaging Council have addressed
this issue. In fact, SPECT scans presented by the consultant used in this
Croft paper have been excluded in court proceedings as being misleading.
The authors invoke other bizarre tests for mycotoxin presence in urine.
They say that urine samples left at room temperature for five months showed
no "putrefaction" and excessive protein at the bottom of the
container. How and why these constitute measures of the presence of mycotoxins
is merely stated with no support and no logical basis. Even assuming that
the authors were finding mycotoxins, the "study" is fatally
flawed by lack of controls. Croft states that one of the authors was the
control, but since he entered the subject homes and felt ill, how could
he have been a control? He was exposed to the environment and had a response
similar to that of the other study subjects.
Finally,
the sheer range of symptoms, as well as the presence of actual serious
and even fatal, diseases described in this article are a veritable compendium
of all human ailments. It would have been quite helpful if the authors
had provided more information about standard diagnostic testing and diagnoses
made by various treating physicians. I strongly suspect, however, that
they would have, had that been possible.
Reference
Croft, W.A., Jastromski, B.M., Croft, A.L., and Peters, H.A."Clinical
Confirmation of Tricothecene Mycotoxicosis in Patient Urine,"
Journal of Environmtl. Biology, 23(3) 301-320, (2002).
About ICTM:
Since 1975, the principals of ICTM have assisted attorneys, corporate
counsel, insurers, and facilities managers in the review and management
of thousands of environmental claims-mold, chemicals and others. The company
has extensive experience in helping attorneys develop strategies and tactics
to support counsel from discovery through motions to exclude experts,
to jury presentations. In addition, ICTM has managed indoor air quality
testing, remediation costs and risk communication for public and private
organizations in hundreds of matters concerning commercial and municipal
buildings, schools, homes, apartments, and condos. ICTM has developed
a methodology that describes the steps needed to evaluate and manage the
medical and toxicological aspects of claims of illnesses allegedly arising
from environmental exposures.
International Center for Toxicology and Medicine
2301 Research Boulevard, Suite 210
Rockville, MD 20850-3204
Phone: 301-519-0300
Fax: 301-519-1307
Web site: http://www.ictm.com
ICTM contact for general information:
Don Franklin
President
E-mail: info@ictm.com
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