allergen – a substance that causes an allergic reaction. Allergens stimulate the body’s immune system to produce antibody proteins, to counteract the allergen. Examples of common allergens include dust, pollen, pet dander and mould.

allergist – a medical doctor who has first specialized in Internal Medicine and then has obtained the additional subspecialty training required to qualify as a specialist in allergy and immunology.

allergy – an exaggerated immune response to allergens, such as insect venom, dust mites, pollen, pet dander, drugs or some foods.

asthma – a common chronic condition affecting the lungs, characterized by inflammation, constriction of the muscles surrounding the airways and excess mucus production.

chronic disease – an illness that lasts for a long time.

cumulative toxic effects – the result of a build-up of a toxin or a number of toxins over time in the body, as a person is repeatedly or continuously exposed.

environmental contaminants – potentially harmful substances that have been released into the environment and have entered our food, water, air and soil.

flare-up – a period in which the symptoms of a disease reappear or worsen.

hidden exposures – exposures to toxins or environmental contaminants that people are unaware of. Exposures occur by breathing in, eating, drinking, touching or injecting a substance.

irritants – substances that irritate the nose, throat or airways (e.g., paint, gasoline fumes, smoke, air pollution); can trigger symptoms of asthma or rhinitis.

inflammation – a reaction of tissues to injury or disease, marked by swelling, redness, heat and pain.

mucus – a secretion produced by the body that covers and lubricates the inner surfaces of the respiratory and digestive tract (where allergic reactions start).

rhinitis – an inflammation of the nasal passages which can cause swelling, sneezing, itching, a runny nose and nasal congestion; sometimes referred to as “hay fever”.

off-gas – to give off fumes. Substances such as solvents, paints, certain cleaning products, plastic materials (e.g., shower curtains) and pesticides “off-gas.”

triggers – factors that can provoke allergic reactions or asthma episodes, including allergens and irritants.

volatile organic compounds (VOCs) – gasses emitted from certain solids and liquids, which can have adverse short- and long-term effects on human health. The thousands of chemicals that are considered VOCs are emitted from products such as paints, paint strippers, varnishes, glues, pesticides, furnishings, building materials, carpet, plastics, gasoline, cigarettes, air fresheners, dry-cleaned clothing, and office equipment, such as photocopiers and printers. VOC levels are generally several times higher indoors than outdoors.