Multiple Chemical Sensitivities
Multiple Chemical Sensitivities (MCS) is a highly
controversial issue. In theory, MCS is an adverse physical reaction to low
levels of many common chemicals. Chemical sensitivity is generally accepted as a
reaction to chemicals but debate continues as to whether MCS is classifiable as an
illness. There are a number of synonyms for MCS, including 20th century disease,
environmental illness, total allergy syndrome, idiopathic environmental illness,
and chemical AIDS.
Proposed theories to explain the cause of MCS include allergy, dysfunction of
the immune system, neurobiological sensitization, and various psychological
theories. There is insufficient scientific evidence to confirm a relationship
between any of these possible causes and symptoms. Due to the lack of definite
information an evaluation must be performed by a physician knowledgeable of the
symptoms of this condition.
Multiple chemical sensitivity (MCS) patients often report
non-specific symptoms from exposure to low-levels of chemical, biological, or
physical agents. There seems to be no single stimuli or predictor of reactions.
The following references aid in recognizing the illnesses and hazards associated
Chemical Sensitivity [212 KB PDF, 3 pages]. The Ohio State University Extension Fact Sheet CDFS-192-08, (2008). Presents a definition of MCS, describes some of the difficulties involved in identifying and defining the disorder, and provides recommendations for reducing chemical exposures.
Evaluation and Management
Limited information is available on effective control measures,
exposure assessments, and regulations dealing with multiple chemical
sensitivities (MCS). However, OSHA does regulate exposures to specific chemical hazards.
For additional information, see OSHA's Safety and Health Topics Pages for Hazardous and Toxic Substances
Many physicians are uncertain how to approach the evaluation and care of persons
who have multiple symptoms attributed to low-level chemical exposure. The
identification of MCS is based largely on the patient's description of the
symptoms and the relationship of these symptoms to environmental exposures. The
following references provide information about the clinical evaluation process
and management of MCS.
Report on Multiple Chemical Sensitivity (MCS). Interagency Workgroup
on Multiple Chemical Sensitivity, (1998, August 24). Provides a public health evaluation of the extent and nature of MCS and
recommends future actions for federal agencies to consider.
- Case Studies in Environmental Medicine: Taking An Exposure History. Agency for Toxic Substances and Disease Registry (ATSDR), (2008, May 12). Also available as a 473 KB PDF, 65 pages. Helps increase the primary care provider’s knowledge of hazardous substances in the environment and to promote the adoption of medical practices that aid in the evaluation and care of potentially exposed patients.
- Magill, M. and A. Suruda. "Multiple Chemical Sensitivity Syndrome." American Family Physician 58(3):721-728. (1998, September 1). Provides a
description of MCS and its symptoms. It also presents recommendations for physicians' evaluation and management of the syndrome.
Related Safety and Health Topics Pages
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