[01] Harold I. Zeliger, Zeliger Research and Consulting, Department of Toxicology, Cape Elizabeth, Maine, USA. [02] Bernard Possidente, Department of Biology, Skidmore College, Saratoga Springs, New York, USA. [03] Abby G. Drake, Department of Biology, Skidmore College, Saratoga Springs, New York, USA.

The co-morbidity of multiple chemical sensitivity (MCS) and chronic fatigue syndrome (CFS) has previously been reported. The present study was aimed to ascertain if either of the two conditions preceded the other in individuals affected with both conditions. An online survey of patients suffering from both MCS and CFS was undertaken. Those suffering from both of these conditions were asked which condition preceded the other. The results showed that 58% of the respondents were co-morbid with both conditions. Approximately half of the respondents reported the onset of MCS first (54%) while approximately half (46%) reported the prior onset of CFS. It is concluded that there is no significant bias with respect to either condition preceding the other in cases of co-morbidity. A mechanism for the onset of these diseases and suggestions for lowering their incidences are made.

Multiple Chemical Sensitivity, Chronic Fatigue Syndrome, Environmental Disease, Disease Co-Morbidity

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