Environmental Intolerances and Toxins-Chemical:  Research Article

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Multiple Chemical Sensitivities

CITATION:  Bell, I. R. (2003). Multiple chemical sensitivities. Psychiatric Times, Volume XX (1)

ABSTRACT:  This aforementioned research article examined the professional controversy applicable to multiple chemical sensitivity (MCS) utilizing a meta analysis approach.  Approximately 6% of the population experiences MCS resulting in contraindications consisting of significant “chemical avoidant behaviors and associated disability.”  Symptomatology of individuals experiencing MCS includes potential “headache, dizziness, difficulty concentrating and/or nausea in response to the odors of low levels of environmental chemicals that the majority of people tolerate with neutral or even positive hedonic effects.”  

The identified chemicals associated with MCS include substances such as pesticides, solvents, perfumes, new carpets, automotive exhaust and tobacco smoke. Additionally, many individuals experiencing MCS symptomatology report multiple intolerances to common foods and medications substantiated through immunoglobulin-G-mediated adverse food reactions.  

Due to conflicting data applicable to immunoglobulin-E-mediated allergies that may substantiate a valid diagnosis of MCS, “evidence for immune system disturbances as the primary mediator of MCS has not been persuasive.”  Based on these findings, the author purports MCS may be associated with potential “secondary adverse effects of chronic psychological and physical stress on cellular and humoral immune function.”  It is further confounding that 80% of individuals experiencing symptomatology of MCS are female.  Identified comorbid psychiatric symptomatology associated with MCS include primarily anxiety, especially panic disorder and depression.  Additionally, individuals experiencing MCS disclose histories of physical, sexual, and emotional abuse at increased rates, however, psychophysiological electroencephalographic patterns of women experiencing MCS differ from women experiencing depression and/or sexually abused women without MCS.  

It has been proposed by some researchers that MCS is a variant of posttraumatic stress disorder (PTSD), however, systematic evaluations of patients with MCS have not found increased rates of PTSD.  The psychological symptoms associated with PTSD include “difficulty falling or staying asleep, irritability, outbursts of anger, difficulty in concentrating, and heightened reactions to sudden noises or movements” (Carlson, 2001, P. 574).  

The physiological methodology of action associated with PTSD involves the secretion of glucocorticoids under the control of the paraventricular nucleus (PVN) of the hypothalamus.  This process commences with the PVN secreting a peptide, corticotrophin-releasing factor (CRF), that subsequently stimulates the anterior pituitary gland to secrete adrenocorticotropic hormone (ACTH) which is then released within the general circulation stimulating the adrenal cortex to secrete glucocorticoids (Carlson, 2001).  Studies have concluded that the most harmful effects of stress are produced by prolonged secretion of glucocorticoids.  The “short-term effects of glucocorticoids are essential, the long-term effects are damaging” (Carlson, 2001, P. 571).  

These aforementioned damaging effects include potential increased blood pressure, damage to muscle tissue, steroid diabetes, infertility, inhibition of growth, inhibition of the immune response, and suppression of the immune system (Carlson, 2001).  It is possible that continued repression of a traumatic experience may produce prolonged secretion levels of glucocorticoids resulting in a plethora of physical and/or psychological contraindications.  “Prolonged exposure to glucocorticoids can cause brain damage in the hippocampus” (Carlson, 2001, P. 574).  Additionally, stress response can impair the function of the immune system impacting an individual’s ability to protect themselves from “viruses, microbes, fungi, and other types of parasites” (Carlson, 2001, P. 576).  

I had the opportunity to provide services to a woman alleging MCS concurrent with presenting issues related to depression and loneliness.  This individual also reported a personal history of sexual/physical abuse and significant grief/loss.  This aforementioned client appeared to rely on her alleged MCS to avoid addressing personal obstacles related to personal growth and subsequently discontinued services in possible avoidance thereof.  This individual appeared to utilize her alleged MCS to remain in the victim role and receive attention.  Laboratory tests and procedures including PET scans and MRI studies may identify increased brain activity and damage related to acute and/or chronic stress.  Additionally, venipuncture and blood analysis, lumbar puncture and cerebrospinal fluid examination may provide additional data applicable to glucocorticoid levels.  Also, urine analysis may provide data related to adrenocortical function (Pagana, 2002).


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