Multiple chemical sensitivity: Difference between revisions

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==Immunological basis==
==Immunological basis==
In a case control study involving 417 persons (223 cases, 194 controls), lymphocyte count was found to be consistent low in victims of MCS.<ref name="pmid15347780">{{cite journal |author=Baines CJ, McKeown-Eyssen GE, Riley N, ''et al'' |title=Case-control study of multiple chemical sensitivity, comparing haematology, biochemistry, vitamins and serum volatile organic compound measures |journal=Occupational medicine (Oxford, England) |volume=54 |issue=6 |pages=408–18 |year=2004 |pmid=15347780 |doi=10.1093/occmed/kqh083 |issn=}}</ref>
In a case control study involving 417 persons (223 cases, 194 controls), lymphocyte count was found to be consistent low in victims of MCS.<ref name="pmid15347780">{{cite journal |author=Baines CJ, McKeown-Eyssen GE, Riley N, ''et al'' |title=Case-control study of multiple chemical sensitivity, comparing haematology, biochemistry, vitamins and serum volatile organic compound measures |journal=Occupational medicine (Oxford, England) |volume=54 |issue=6 |pages=408–18 |year=2004 |pmid=15347780 |doi=10.1093/occmed/kqh083 |issn=}}</ref>
==The TILT theory of environmental diseases==
Claudia Miller of the University of Texas points out that the term ''multiple chemical sensisitivities'' erroneously suggests that the MCS patient is only intolerant to so-called "chemicals", while the evidence rather suggests that people with MCS react as well to very low levels of common food ingredients, such as xanthines and, for example, alcohol.
The Toxicant-Induced Loss of Tolerance (TILT) model describes more closely MCS by specifying that, in this syndrome, there is a generalized loss of tolerance to many unrelated and otherwise benign molecules, and that this loss of tolerance is indeed due to an exposure to toxics (or "toxicants").<ref name="pmid9167978">{{cite journal |author=Miller CS |title=Toxicant-induced loss of tolerance--an emerging theory of disease? |journal=Environ. Health Perspect. |volume=105 Suppl 2 |issue= |pages=445–53 |year=1997 |pmid=9167978 |doi= |url=http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1469811}}</ref>


==References==
==References==

Revision as of 19:17, 17 November 2007

Multiple chemical sensitivities, also known as environmental intolerances, is a poorly understood and often disputed syndrome which is described using the following criteria:

  • The symptoms are reproducible with repeated chemical exposure;
  • the condition is chronic;
  • low levels of exposure (lower than previously tolerated) result in manifestations of the syndrome;
  • the symptoms improve or resolve when the incitants are removed;
  • responses occur to multiple chemically unrelated substances; and
  • symptoms involve multiple organ systems.[1]

Epidemiology

(in progress)

Genetic basis

People diagnosed using the 1999 consensus statement criteria[1] have significant differences in some drug-metabolizing enzymes and other enzymes involved in detoxication.[2] These findings, which require replication, point to an unequivocal somatic and toxic basis to multiple chemical sensitivities.

Immunological basis

In a case control study involving 417 persons (223 cases, 194 controls), lymphocyte count was found to be consistent low in victims of MCS.[3]

The TILT theory of environmental diseases

Claudia Miller of the University of Texas points out that the term multiple chemical sensisitivities erroneously suggests that the MCS patient is only intolerant to so-called "chemicals", while the evidence rather suggests that people with MCS react as well to very low levels of common food ingredients, such as xanthines and, for example, alcohol.

The Toxicant-Induced Loss of Tolerance (TILT) model describes more closely MCS by specifying that, in this syndrome, there is a generalized loss of tolerance to many unrelated and otherwise benign molecules, and that this loss of tolerance is indeed due to an exposure to toxics (or "toxicants").[4]

References

  1. 1.0 1.1 (1999) "Multiple chemical sensitivity: a 1999 consensus". Arch. Environ. Health 54 (3): 147–9. PMID 10444033[e]
  2. McKeown-Eyssen G, Baines C, Cole DE, et al (2004). "Case-control study of genotypes in multiple chemical sensitivity: CYP2D6, NAT1, NAT2, PON1, PON2 and MTHFR". International journal of epidemiology 33 (5): 971–8. DOI:10.1093/ije/dyh251. PMID 15256524. Research Blogging.
  3. Baines CJ, McKeown-Eyssen GE, Riley N, et al (2004). "Case-control study of multiple chemical sensitivity, comparing haematology, biochemistry, vitamins and serum volatile organic compound measures". Occupational medicine (Oxford, England) 54 (6): 408–18. DOI:10.1093/occmed/kqh083. PMID 15347780. Research Blogging.
  4. Miller CS (1997). "Toxicant-induced loss of tolerance--an emerging theory of disease?". Environ. Health Perspect. 105 Suppl 2: 445–53. PMID 9167978[e]