CFS and Chemical Exposure

Patients with CFS often react to chemical exposures in a similar manner to those with MCS. Though, as discussed earlier, the initial onset of CFS is widely believed to be preceded by a viral infection or flu-like illness, CFS cases have been reported, however, following chronic and acute exposures to chemicals. These are  

Researchers at the National Reference Center for CFS Study at the Department of Infectious Diseases of G. D Annunio University in Chieti, Italy, reported that five individuals developed clinical features of CFS several months after their exposures, two to the food poison ciguatera and three to organic solvents. I53l 

CFS was reported in 10 farmers in the United Kingdom as a delayed reaction following chronic low-dose exposure to organo-phosphates, including malathionJ54 The onset of CFS symptoms in all except one was preceded by a flu-like illness. In the tenth, CFS was preceded by cholecystitis. Due to this, it is not clear whether the pesticide exposures alone were the CFS causative agents in this study. 

Pesticides were further implicated as causative agents for CFS in a Spanish study that reported on 26 people who developed CFS following their return to a workplace that had been fumigated J56l 

With the exception of the Spanish study, all the reported CFS cases followed long-term, chronic exposures or disease onset long after exposure. In the British study, infections immediately preceded the reported onset of CFS. These studies, while suggestive, do not establish a causal relationship between chemical exposure and CFS. CFS has immune, nervous, and endocrine system involvement. It should not be surprising, however, that chemicals that affect these body systems can contribute to, if not be a cause of, CFS. This subject is pursued further in Section 26.12. 

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