An olfactory-limbic model of multiple chemical sensitivity syndrome: Possible relationships to kindling and affective spectrum disorders

Journal Article · Sat Aug 01 00:00:00 EDT 1992 · Biological Psychiatry; (United States)

DOI:https://doi.org/10.1016/0006-3223(92)90105-9· OSTI ID:6899560

Bell, I R; Miller, C S; Schwartz, G E ^[1]

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1. Univ. of Arizona Health Sciences Center, Tucson (United States)

This paper reviews the clinical and experimental literature on patients with multiple adverse responses to chemicals (Multiple Chemical Sensitivity Syndrome-MCS) and develops a model for MCS based on olfactory-limbic system dysfunction that overlaps in part with Post's kindling model for affective disorders. MCS encompasses a broad range of chronic polysymptomatic conditions and complaints whose triggers are reported to include low levels of common indoor and outdoor environmental chemicals, such as pesticides and solvents. Other investigators have found evidence of increased prevalence of depression, anxiety, and somatization disorders in MCS patients and have concluded that their psychiatric conditions account for the clinical picture. However, none of these studies has presented any data on the effects of chemicals on symptoms or on objective measures of nervous system function. Synthesis of the MCS literature with large bodies of research in neurotoxicology, occupational medicine, and biological psychiatry, suggests that the phenomenology of MCS patients overlaps that of affective spectrum disorders and that both involve dysfunction of the limbic pathways. Animal studies demonstrate that intermittent repeated low level environmental chemical exposures, including pesticides, cause limbic kindling. Kindling (full or partial) is one central nervous system mechanism that could amplify reactivity to low levels of inhaled and ingested chemicals and initiate persistent affective, cognitive, and somatic symptomatology in both occupational and nonoccupational settings. As in animal studies, inescapable and novel stressors could cross-sensitize with chemical exposures in some individuals to generate adverse responses on a neurochemical basis. The olfactory-limbic model raises testable neurobiological hypotheses that could increase understanding of the multifactorial etiology of MCS and of certain overlapping affective spectrum disorders. 170 refs.

• OSTI ID: 6899560
• Journal Information: Biological Psychiatry; (United States), Vol. 32:3; ISSN 0006-3223
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
59 BASIC BIOLOGICAL SCIENCES
HUMAN POPULATIONS
NERVOUS SYSTEM DISEASES
PESTICIDES
BIOLOGICAL EFFECTS
SOLVENTS
AIR POLLUTION
CENTRAL NERVOUS SYSTEM
CENTRAL NERVOUS SYSTEM AGENTS
CENTRAL NERVOUS SYSTEM DEPRESSANTS
CHRONIC EXPOSURE
ENVIRONMENTAL EXPOSURE
ETIOLOGY
LEVELS
MENTAL DISORDERS
NERVOUS SYSTEM
NEUROLOGY
PATIENTS
RANGE
REACTIVITY
SENSITIVITY
SYMPTOMS
DISEASES
DRUGS
MEDICINE
POLLUTION
POPULATIONS
560300* - Chemicals Metabolism & Toxicology
550100 - Behavioral Biology