Allergen Update

Vancouver, British Columbia

Predominant pollen:

Acer sp.- Maple season can start from mid-March to early April and end late April to late May. Mostly low (with occasional moderate) counts are observed. Not considered to be important allergens.

Alnus sp.- Alder season starts from late January and lasts until late June to mid-July. The season varies from year to year due to weather and seasonal trends. The counts fluctuate from low to very high throughout the season due to the number of species present. The highest counts are observed starting mid to late February and last to mid-June. This is considered the most important allergen at this location.

Betula sp.- The birch season can start from mid-March to early April and can end early to late May. High counts are observed and they are considered important in causing allergic reactions.

Populus sp.- The poplar, cottonwood and aspen season can start from late February to late March and end late April to early May. Most of the season produces moderate and low counts. May cause allergic reactions only in individuals who are highly sensitized.

Cupressaceae family- The cedars, junipers and yews produce very high counts from late January to late May. The season lasts until early July with low and moderate counts.

Corylus sp.- The hazelnuts produce some moderate counts during the months of January and February. May cause allergic reactions in individuals who are highly sensitized.

Fagus sp.- Sylvatica and grandifolia are two species present at this location. The beech some years produce moderate counts but the season varies a great deal from year to year due to the effect of weather. The season can last from mid-April to mid-May. May cause allergic reactions in individuals who are highly sensitized.

Pinaceae family- This includes the spruce, fir and pine trees. Some high, but mostly low and moderate counts are observed from mid-April to mid-July. The season varies from year to year but not as much as in some of the other sites outside of British Columbia. Considered very important allergens to those individuals who are sensitized.

Tsuga sp.- The hemlocks produce low to moderate counts and the season can occur between mid-March to late June. The season is very sporadic from year to year and lasts almost two months. May cause allergic reactions in individuals who are highly sensitized when shed in high numbers.

Quercus sp.- The oak season can occur from mid-April and end late May with a few moderate and very occasional high counts observed. The pollen season can vary by as much as two weeks. Allergic reactions can occur when large quantities of pollen are released.

Ulmus sp.- The elm season can start between late January and early March and last from early to mid-April. Mostly low to moderate, with the occasional high, counts are observed. The elms are considered important allergens.

Larix sp.- The larch and tamaracks produce low to moderate counts. There are two seasons that can occur between late March to late May. This is probably due to the number of species present. The season lengths and amount of pollen produced can fluctuate a great deal from year to year.

Gramineae family- The grasses produce moderate counts, from June to the end of July, a few high counts can be observed for certain years. The season is from late May to late September.

Ambrosia sp.- Ragweed is rarely observed in our air samples at this site. This weed is not abundant and only occurs in small patches.

Urticaceae sp.- The nettles and parietaria produce a few moderate counts from mid-May to late June. The season is sporadic. They are considered important in causing allergic reactions due to the small size of the pollen.

Plantago sp.- The plantains produce low counts from June to mid-September. May be of importance to those highly sensitized (see information on Plantains in pollen section).

Rumex sp.- The pollen of dock or sorrel is of minor importance in causing allergic reactions.

Predominant spores:

Diatrypaceae sp.- The counts are sporadic throughout the whole counting season. Very high counts can be observed from the end of January to mid-October. Not known to cause allergic reactions.

Erysiphe (Oospora) sp.- Powdery mildew - The season is from late January to well into October. There are very high counts in August and September and the season is very sporadic.

Leptosphaeria sp. and Leptosphaeria look-alikes- These two are grouped together since they are in the same class of fungi and are similar microscopically. The season starts mid-February to mid-October. The counts vary from day to day, which is probably due to the effect of weather. Mostly moderate, with occasional high, counts are observed.

Boletus sp.- The counts for this spore are very sporadic with moderate counts observed. It may be of significance in causing allergic reactions. The season with moderate and high counts is from mid-June to mid-October.

Coprinus sp.- The season for this mushroom, where significant counts are observed, is from April to mid-October. It is considered an important allergen.

Ganoderma sp.- This bracket fungus can produce significant counts from January to well into late fall. Very high counts are observed from April to late fall. It is considered an important allergen.

Uredinales sp.- The rusts produce low to moderate counts from May to mid-October. Not enough is known about their significance in causing allergic reactions at these levels.

Ustilaginales sp.- The allergenic properties of the smuts are unknown. However, they belong to the Basidiomycota, which are associated to allergies and asthma. The season is from mid-April to mid-October with some high counts throughout the season.

Alternaria sp.- The counts are in the low to moderate range. Some species are known to cause allergic reactions. The season with the highest counts is from August to the end of September.

Penicillium sp. & Aspergillus sp.- These spores are found throughout the whole counting season and are probably present in significant numbers beyond that. The counts can be high from January to late fall.

Botrytis sp.- This may be a significant allergen. The season is from January to late fall and the counts are very sporadic. Some very high counts are observed throughout the season but the highest occur in the late summer and fall.

Cladosporium sp.- The most abundant spore found throughout the whole season. This spore exists all year round and very high counts are known to occur starting January to well into late fall.

Epicoccum sp.- Some species are known to cause allergic reactions. The main season, with low to moderate counts, is from May to mid-October. May not be a significant allergen.

Helicomyces sp.- Season is from February to mid-October producing very high counts from June to August. The season is very sporadic.

Pithomyces sp.- The season for this fungus is from June to the end of September producing low to moderate counts with some in the high range.

Polythrincium sp.- The season if from June to the end of August with low to moderate counts. Allergenic properties are unknown.

Myxomycetes- The season is very sporadic with low to moderate counts from June to the end of September.

Last updated: March 2015

The information presented here is designed to inform, not replace, the relationship that exists between a patient and a medical professional.

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