and Clinical Presentation of the Chemically Sensitive Patient
by Gerald H. Ross, MD, CCFP,
Environmental Health Center-Dallas,
Source: This article
is exerpted from the original published in 1992 in Toxicology and Industrial
Health, 8(4), 21-28. The graphics included in the original publication
are not presented here. They can be obtained via a written request. Address
all requests/ correspondence to Dr. Gerald H. Ross, Environmental Health
Center-Dallas, 8345 Walnut Hill Lane, Suite 205, Dallas, TX 75231.
Early in 1991, an advertisement
illustrating the growing public awareness of potential problems with sensitivities
to common substances around us appeared on the back cover of Good Housekeeping
magazine. It showed a little girlís party dress on a hanger, obviously
not being used, with the title, "How can such a nice dress be so irritating?"
The ad explained the benefits of a new laundry product made without perfumes
or dyes and implied the new laundry liquid would not leave chemical residues
in the fabric that would subsequently irritate little girlsí sensitive
skin. It is doubtful that such an ad, expressing concern about the chemical
residues we are all exposed to in modern society, would have appeared ten
years ago,. This advertisement may be a sign of the times.
Chemical sensitivity is
an abnormal state of health characterized by intensified and adverse responses
to components found in food, air, water, or physical surroundings of the
patientís environment (Hileman, 1991). The provoked symptoms or signs may
be chronic, relapsing, or multisystem and are triggered by levels of exposure
that are generally well tolerated by most people. The diagnosis is suspected
on the basis of history and physical examination, and the condition may
be confirmed by removing the offending agents and rechallenging patients
under properly controlled conditions. The clearing or improvement of symptoms
or signs by removing the suspected substances and the recurrence or worsening
after specific, low-level challenge is highly indicative of environmental
hypersensitivity and, in this context, chemical sensitivity. This definition
is very similar to that proposed by Ashford and Miller (1989) in their
report to the State of New Jersey and in their subsequent book (Ashford
and Miller, 1991).
If we consider a patientís
total environment as a complex interplay of genetic endowment; nutritional
status; emotional stress; and exposure to foods, chemicals, microbes, inhalants,
and even electromagnetic fields, then the expression of health is a function
of the interplay of those factors and their effect on the patient (Randolph,
1962). Also necessary and important is the concept frequently used in environmental
medicine of biochemical individuality, which is essentially the metabolic
uniqueness that characterizes each person. No two individuals are identical
in how they respond to a stressor (Calabrese, 1984). Although basic common
sense and the lessons leamed in medical school point to the concept of
metabolic uniqueness, it is often overlooked in medical practice. For example,
probably 10% of the population are slow metabolizers of the drug debrisoquine
(Brostoff, 1987). The genetic polymorphism that determines fast or slow
metabolism may be an important factor in expressing susceptibility to certain
diseases or reactions to toxic environmental chemicals. Thus, the genetic
variation (predisposition), phenylketonuria (PKU), sets the stage for severe
problems if too much phenylalanine (stressor) is taken in the diet. Similarly,
food-sensitive migraine patients frequently have phenylsulfotransferase
deficiencies that may contribute to the onset of headaches when certain
foods are consumed (Brostoft, 1987). Individually, many persons may have
inborn variations of metabolism that predispose them to potential problems
with metabolism or detoxication of substances in the chemical environment
Randolph (1980), in his
excellent book, An Alternate Approach to Allergies, describes the
chemically sensitive patient: "Typically, however, patients have been polysymptomatic;
that is, they have a long history of many problems, physical and mental,
which have left them in a general state of misery. The more symptoms they
accumulated, the less the doctors believed their complaints." All too often,
once the physician reaches the end of the diagnostic repertoire for classifying
a patientís complaints, the patient tends to be classified (by default)
as having a functional or psychologic origin for confusing symptoms. This
difficulty with diagnosis involving complex symptoms does not necessarily
indicate a problem patient but perhaps a physician who lacks the proper
knowledge to make a correct diagnosis.
Survey of Chemically Sensitive
Future discussions of patients
with multiple chemical sensitivity (MCS) may be aided by statistical data
from a large survey, conducted by the staff at the Environmental Health
Center in Dallas, Texas, of more than 200 consecutive patients being investigated
and treated in the Environmental Control Unit (Sprague, 1987). The Environmental
Health Center is a multidisciplinary facility of physicians, psychologists,
research scientists, and support staff who have extensive experience with
patients referred from around the country with symptoms of chemical sensitivity.
This clinic is specially constructed with porcelain-on-steel walls and
ceilings, terzazzo tile floors, extensive air-filtration systems, and other
controls to minimize indoor air pollution and maximize the likelihood of
patients being in a baseline state before appropriate investigation and
treatment of allergies or chemical sensitivities.
Age distribution of the patients
is shown in Figure 1. Consistent with findings of other studies, about
three-quarters of these patients are women. Most present for evaluation
in their 20s, 30s, or 40s but report that symptoms atributable to environmental
problems first started at a much earlier age, even in the teenage years
and earlier (Figure 2). Although disturbing in some respects,
this information is encouraging because it raises the possibility of early
intervention to prevent progression of this condition.
The number of physicians previously seen by these patients varied, but
it was not unusual for a patient to have consulted as many as 20 doctors
in trying to find answers for their unusual health problems Figure 3).
The education level in this group tended to be rather high; many were college
educated Figure 4). These patients represented a wide spectrum of occupations
and trades, including business, sales, labor, law, teaching, technical
trades, other professionals, clergy, physicians, other medical personnel,
clerical workers, homemakers, artists, students, and engineers (Figures
5a and 5b).
Typically, the family history
in many of these patients was positive for classical allergy, and the likelihood
of migraine headaches, alcoholism, thyroid dysfunction, collagen vascular
diseases, or psychiatric diagnoses in the family appeared high. A careful
history of these patients might reveal a significant deterioration in their
health after some identifiable event, such as redecorating the house, the
arrival of a new baby, prolonged recovery from the flu, moving into a new
building, or exposure to pesticides.
The most frequent complaints
in this survey of patients ranged from headache, fatigue, confusion, depression,
shortness of breath, and arthralgia, to myalgia, nausea, dizziness, memory
problems, gastrointestinal symptoms, or respiratory symptoms (Figures 6a
and 6b). Neurologic symptoms, including migraine, poor memory, confusional
states or "brain fag," tremor, weakness, and numbness, seemed to top the
list. Patients frequently reported anxiety, depression, irritability, and
dizziness, and some also reported that noise particularly irritated them.
On occasion, they reported being tearful, with a higher-than-usual incidence
of addiction. A frustrating aspect for these patients (and their doctors)
was a lack of consistent and pathognomonic physical indicators of MCS.
Patients sometimes said, "I feel so awful, that if one more person tells
me how good I look, Iíll scream!"
Despite the lack of universally
consistent physical findings in chemically sensitive patients, certain
characteristics are seen more often than not. Although anecdotal, it may
help physicians interested in MCS to know that chemically sensitive patients
are more likely to have unstable physical balance, to be easily confused,
and to have poor memory that can be measured objectively on neurologic
evaluation (Rea, 1984). Frequently, they complain of cold hands and feet,
possibly from autonomic instability and vascular spasms. They are much
more likely to be underweight than overweight. The women may have a history
of fibrocystic breast disease or thyroid dysfunction, and many have coated
or geographic tongues and develop aphthous ulcers after eating certain
foods. Children have a high incidence of learning disabilities or hyperactivity,
often get very sleepy after lunch, and may he quite erratic in their school
work. Patients with chemical sensitivities often have food cravings, histories
of food and other addictions, and may experience withdrawal symptoms when
they go without certain foods. Children especially may exhibit Jekyll-and-Hyde-type
sudden personality or mood changes (Rapp, 1991).
Chemically sensitive patients
may be diagnosed objectively, however, and this is perhaps best demonstrated
on double-blind, placebo-controlled, low-dose chemical challenges, under
environmentally controlled conditions (Rea, 1990a).
Although no one has all
the answers to the mystery of chemical sensitivity, the reality of this
condition, most recently called multiple chemical sensitivities, is not
in doubt. Evidence is increasing of its possible physiologic mechanisms,
which will be discussed later in this volume. From the evidence and from
personal and professional experience, the author believes that chemical
sensitivity is not a diagnosis of exclusion and that fixed-name diseases
may have environmental triggers or complicating factors (Rea, 1990b). With
appropriate preparation and environmental controls, MCS can be investigated
and diagnosed in a scientific and reproducible manner.
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New York: Wiley.
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Rea, W. J., Ross, G. H., Johnson,
A.R., et al. (1990a). Confirmation of chemical sensitivity by means of
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