Pathways into the body

Exposure to initiating and triggering agents can take place via the respiratory system, the digestive system, skin contact, contact with infectious agents, injection of products and medical interventions. Exposure can happen as early as mother to child transmission during pregnancy and breastfeeding.

The body reacts differently depending on the type of exposure and whether it is a chemical, physical or biological contaminant.

Table 1 Agents likely to bring about the onset of environmental sensitivities.

Type of agent

Examples of agents

Examples of sources or products

Volatile Organic Compounds (VOCs)


Urea-formaldehyde foam insulation* Wood glues** (e.g. plywood and pressed wood/ chipboard) Paint


Varnishes Paint thinners and strippers, glues Air fresheners


Perfumes, personal care products, Household cleaning products Fabric softeners

Off-gassing mixtures

Equipment (e.g. computers) Furniture

Products containing petrochemicals

Carpets Ink from books and periodicals Fuels, petroleum

Combustion products

Tobacco smoke Vehicle exhaust Barbecue or wood smoke

Cigarettes, Buses, trucks, cars Barbecues, wood stoves, fireplaces

Microbial products

Moulds Mycotoxins Bacteria Metabolites produced by moulds or bacteria

Mould or bacteria in structures Mould or bacteria in ventilation and air conditioning systems
Microbes in older documents Mouldy furniture Soil (plants)



Products to kill insects
Products used to kill weeds Products used to kill fungi Swimming pools products, including chlorine

Natural inhalants

Animal dander

Tree pollen (Spring)
Ragweed (August-September) Dogs, cats, horses, etc.


Allergenic proteins Preservatives Individual/specific flavouring agents

Peanuts, milk, gluten
Sulfites in dried fruits and wine Monosodium glutamate (MSG) Artificial flavours and colours Curry, cinnamon, hot pepper

Electromagnetic radiation


Fluorescent light bulbs

Radio waves and microwaves

Wiring problems
Energy-efficient devices Computers

Very low-frequency electromagnetic fields

Telecommunications equipment Power lines

Telluric currents

Power supply systems that let the current pass through the ground, pipes or structures

Other factors


Workplace or home infrastructure

* Now prohibited in Canada. ** Prohibited in new products in many countries. Source: Sears, 2007.

Share you resources!

Persons suffering from environmental sensitivities generally have a vast amount of information as far as the resources available in the region.
Do you know understanding professionals who are aware of ES and can provide accommodation? The best places to buy healthy products or where to get services? Why not share your information?


UQAM - service au collectivitésTELUQ
Association pour la santé environnementale du Québec
Logo-Quebec invWith the financial support of the Ministry
of Education, Recreation and Sports (Québec)

Translation from French to English has been made possible in part by the Department of Canadian Heritage and ASEQ-EHAQgovcan-e-col