Overview

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Research Program

Initiating factors, triggers and symptoms of environmental sensitivities, and their impacts in the workplace

People with sensitivities have individual susceptibilities to various environmental factors. As seen in Table 6, the more common agents that trigger reactions in susceptible people include pesticides, volatile organic compounds (VOCs) such as solvents, perfumes, formaldehyde and other petrochemicals, vehicle exhaust, moulds, pollens, foods, animal danders and electromagnetic phenomena. These may arise from the workplace structure, furnishings, equipment, exterior surroundings or cleaning products, or from co-workers and clients. Other aspects of the environment, including electromagnetic radiation, currents and fields, lighting, humidity, heat, cold and noise may also exacerbate environmental sensitivities.

Once people are initially sensitized to low levels of environmental factors, they may experience reactions triggered by a broader range of exposures if the condition is not recognized and addressed. In this two-stage process, environmental sensitivities may develop gradually with chronic exposure to relatively low levels of chemicals as seen in "sick buildings," or suddenly after a major exposure to an environmental disaster or a chemical spill.

* urea-formaldehyde insulation has been banned in Canada

** formaldehyde-containing glues are banned in new products in many countries including Europe, Japan and China

Symptoms of environmental sensitivities are unique to the individual. Some possible symptoms are summarized in Table 7.

Sensitivity reactions to chemicals may vary for acute or chronic exposures. A single, isolated low-level exposure (e.g. perfume on someone several seats away in the theatre or bus, that is not obviously harming the wearer) may cause significant symptoms such as headache, confusion, breathing difficulties or loss of balance in a person with environmental sensitivities. These symptoms may take minutes, hours or days to resolve. However, regular exposure to something to which one is sensitive may lead to habituation or "masking," and chronic ill-health that may even be accepted as normal.³ Habituation is also the reason why research into sensitivities would benefit from an environmental medical unit with high quality air, water, food and surroundings, so that affected people attain a "baseline" unmasked level of health.^72,73 A study found that people with environmental sensitivities do not adjust as quickly as healthy volunteers to research situations, so deficiencies in trial design may explain inconclusive studies in the scientific literature.^72,74

Table 7: Environmental sensitivity symptoms/reactions ^5,60,75,76

Impacts of environmental sensitivities in the workplace

Almost everyone with environmental sensitivities has neurological symptoms. Two concerns are that neurological symptoms may not be recognized (may be "masked") when exposures are chronic,³ and that cognitive impairment may not be reported in the workplace where consistent mental acuity, strength and/or coordination are important for both executing one’s job and advancement. Other symptoms of ill health may make continued employment difficult.

Many people with environmental sensitivities end up changing their work, becoming under-employed or unemployed. This may be driven by lack of accommodation, and health may deteriorate as people face ongoing triggers in the workplace.^28,77,78

Improving indoor environmental quality will potentially benefit many more people than the individual identified with sensitivities. Workers are more productive and general symptoms of "sick building syndrome" may improve when ventilation is improved ^79-82 or a pollution source is removed from offices.^83,84 Children are healthier and learn better when indoor environmental quality is improved in schools.^8,85-87

Summary

Sensitivities may be initiated by a range of environmental factors and once the condition is initiated, reactions may be triggered by a broadening array of incitants. Environmental sensitivities may affect every system in the body, so multiple symptoms are possible, with variation among individuals. Neurological symptoms are almost universal. Common incitants are summarized in Table 6 and symptoms are summarized in Table 7. The impact of environmental sensitivities on workers’ performance may range from mild (e.g. habituation to chronic exposures such that performance may be sub-optimal, although not "abnormal") to severe impairment such that work is impossible. The health and ability to work for those with environmental sensitivities rests with the choices and actions of others, such as building managers, co-workers and clients.