An overview of MCS (excerpt)
The latest research strongly suggests that chemical sensitivity is most probably some combination of central nervous system and blood-brain barrier damage, low-level porphyrin abnormalities, and detoxification enzyme deficiencies. Chemical sensitivity is more often than not characterized by real, verifiable damage to the body, though the implications of these anomalies are poorly understood and need research.
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Two other factors help complicate the process of unraveling chemical sensitivity. They are masking (adaptation) and spreading (cross sensitization). A very simplistic explanation of the very complicated process of masking is that the body forms an addiction to a chemical so that if a person doesn't get a regular dose of the chemical, the body will go into withdrawal much like that associated with drug or alcohol addiction. While overt symptoms are being controlled by the masking, internal damage continues unchecked. Spreading can turn chemical sensitivity into a progressive condition. Once a person is sensitized to one chemical, the sensitivity can spread to include other unrelated compounds. Once that happens, repeat exposures reduce the body's tolerance level by an as yet unknown mechanism so the body becomes more easily reactive to more and more chemicals at lower and lower levels until it finally reaches the point where the person is sick all the time. If this illness reaches that point, the person can kiss a life of casual convenience good-bye.
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Then in 1994, testing showed that over 90% of MCS sufferers have developed a condition known as Disorders of Porphyrinopathy (an acquired form of the porphyrias). The porphyrias are a group of rare metabolic, enzyme deficiency disorders involving the production of heme (a component of blood) and liver and/or bone marrow damage and have many symptoms in common with MCS. The most significant symptom MCS shares with the porphyrias are chemical intolerance/sensitivity and any estrogen mimicking chemical or drug can trigger an attack.
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Two other factors help complicate the process of unraveling chemical sensitivity. They are masking (adaptation) and spreading (cross sensitization). A very simplistic explanation of the very complicated process of masking is that the body forms an addiction to a chemical so that if a person doesn't get a regular dose of the chemical, the body will go into withdrawal much like that associated with drug or alcohol addiction. While overt symptoms are being controlled by the masking, internal damage continues unchecked. Spreading can turn chemical sensitivity into a progressive condition. Once a person is sensitized to one chemical, the sensitivity can spread to include other unrelated compounds. Once that happens, repeat exposures reduce the body's tolerance level by an as yet unknown mechanism so the body becomes more easily reactive to more and more chemicals at lower and lower levels until it finally reaches the point where the person is sick all the time. If this illness reaches that point, the person can kiss a life of casual convenience good-bye.
...
Then in 1994, testing showed that over 90% of MCS sufferers have developed a condition known as Disorders of Porphyrinopathy (an acquired form of the porphyrias). The porphyrias are a group of rare metabolic, enzyme deficiency disorders involving the production of heme (a component of blood) and liver and/or bone marrow damage and have many symptoms in common with MCS. The most significant symptom MCS shares with the porphyrias are chemical intolerance/sensitivity and any estrogen mimicking chemical or drug can trigger an attack.