​We get more complaints about odour than any other type of air emission.  Residents mention being unable to enjoy their own property and outdoor activities, such as gardening and barbeques, and even having to close their windows and doors during hot weather.   

Odour is the sensation that is caused by breathing in odorous air contaminants.  Usually, a mixture of contaminants is involved, which makes odour very difficult to measure.  Some odours will mask others (that’s how air fresheners work) and sometimes the combination of two odours is worse than either alone (for example two perfumes that just don’t work together). 

Although the levels of individual odorous air contaminants can be measured with equipment, the best instrument for measuring odour is the human nose. Some people have far more sensitive noses and will smell an odour at much lower levels than others. In addition, an odour that one person may like may be objectionable to another, such as smells from perfume stores, coffee roasters, bakeries or a brewery. 

Metro Vancouver regulates odorous air contaminants by targeting specific sources and contaminants in industrial permits.

Odorous air contaminants

Odorous air contaminants are made up of many different compounds, some of which are immediately harmful to human health but many of which are not. At the low levels typically found in residential areas, most odorous air contaminants are more a nuisance than a health hazard. However, a number of physiological responses have been reported in scientific papers, including watering eyes, headache, nausea, vomiting, loss of appetite, upset stomach, and throat irritation. Sleeplessness, stress and anxiety are also reported effects and, if experienced for prolonged periods, can result in chronic health impact.

Category Odorous Air Contaminant Smells Like
Ketones and AldehydesAcetone Nail polish remover, pungent, solvent
Formaldehyde Disinfectant, pungent, acrid, medicinal
Volatile Sulphur CompoundsCarbon disulfide Disagreeably sweet, rotten pumpkin
Hydrogen sulfide Rotten eggs
Methyl mercaptan Pungent, skunk, garlic, sewer, rotten cabbage, natural gas
Dimethyl sulfide, Dimethyl disulfide Putrid, sulphurous
Naphthalene Moth balls, tar like
Sulphur dioxide Burnt match
Volatile Nitrogen CompoundsAmmonia Window cleaner, urine, pungent, sharp, irritating
Amines (e.g. methylamine, dimethylamine…) Putrid, fishy, rotten fish, fertilizer, ammoniacal, pungent
Diamines (Cadaverine, Putrescine) Putrid, nauseating, rotten flesh
Skatole, Indole Excreta, faecal matter, nauseating
Volatile Fatty AcidsAcetic acidVinegar like, pungent
Butyric acid Rancid butter, body odour, garbage
Valeric acid Unpleasant, body odour
Iso-valeric acid Foot odour, rancid cheese
Other Odorous Air ContaminantsChlorineBleach, swimming pool
BenzeneSolvent, gasoline
EthanolPleasant, sweet