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Environmental Sensitivities

CITATION:  Joffres, MR, Williams, T, et al.  (2001).  Environmental Sensitivities: Prevalence of Major Symptoms in a Referral Center: The Nova Scotia Environmental Sensitivities Research Center Study,  Environmental Sensitivities: Prevalence of Major Symptoms in a Referral Center: The Nova Scotia Environmental Sensitivities Research Center Study.

Environmental sensitivities (ES) are still considered by many to be an enigmatic health concern. Within the medical community, disparate views on the origins and pathophysiology abound (1–15). Nevertheless, individuals continue to experience symptoms that produce varying degrees of disability. The most frequently cited term to describe this clustering of medically unexplained symptoms has been multiple chemical sensitivities (MCS), originally coined by Cullen in his initial paper on workplace health risks (16). Several theories have been advanced to explain the diverse symptoms occurring after exposure to low-level irritants, foods, or electromagnetic radiation (1,3,4,5–15). In the 1995 Nova Scotia Health Survey, 3% of the population reported being environmentally sensitive (17). A more recent study conducted by Kreutzer et al. (18) stated that 16% of Californians reported being “allergic or unusually sensitive to everyday chemicals.” There were no specific questions on symptoms other than a list of products or situations “bothering” or making individuals “sick.” In a telephone survey conducted in North Carolina, Meggs et al. found that 33% of those surveyed reported sensitivity to chemicals (19), and 4% of the total population reported daily or almost daily frequency of their symptoms. The most common symptoms among individuals with chemical sensitivity were nausea (47%), headache (33%), and eye irritation (16%). There was no detailed evaluation of symptoms in this phone interview survey. Kipen et al. (20) found a prevalence of sensitivity to chemicals of 13% among Gulf Registry Veterans (20). Common within all these reports was the need to explore further and more accurately describe this phenomenon. To answer this need, we used a symptom-based questionnaire to explore the frequency, severity, and type of symptoms experienced by a Canadian patient population referred to a specialty center for environmental sensitivities.


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