Representative genus: Pinus.
Do not confuse with the Australian Pine tree
The Pine tree is an evergreen conifer, reaching a height of 15-35 metres. The outer bark is narrowly ridged and the inner bark is resinous. The needles occur in clusters of three and are 10-15 cm long and persist on the tree for approximately 3 years. Cones are 7.5-14 cm long. The Pine tree can live for 90 years.
The Pine tree is a common name for a family of coniferous trees, of widespread distribution in the temperate areas of the Northern hemisphere.
Northeastern America is the native location for white Pine. Cultivation was attempted in Europe but was given up because of a fungus disease. Of the 100 different species included in the genus, almost all are found in the Northern Hemisphere, with 36 in North America. Pinus radiata, or Monterey Pine, has become the most important in the Southern Hemisphere. P. radiata should not to be confused with the Australian Pine tree (Casuarina family). Family members include the Douglas Fir tree, the Spruce tree and the White Pine tree. Pines are distinguished from other members of the family by the leaves, which are in bundles. Pines can be divided into two groups, hard Pines and soft Pines.
Pines grow in a wide range of habitats, from sea level to altitudes of 2,400 m in Europe. The climate where Pine trees grow best is humid with mild year-round temperatures. Winters are wet. The optimum soil is an acidic, deep, sandy loam with a clay layer.
Most Pinus species flower in early summer. The male and female flowers are separate but on the same tree. The males form cylindrical catkins and the females form cones. Pollination occurs from January to February in the Northern Hemisphere, but may be extended due to high temperatures. The pollen count is often high but the pollen grains are large, this being a possible reason for the low induction of sensitisation. Cones are produced annually. They may remain closed for several years, depending upon temperature and humidity. Cones open and release seed during warm, dry periods and close rapidly when temperature drops and relative humidity increases.
Although pine pollen is said not to be dispersed over a wide area by wind, a study reported that pine pollen had been found in airtraps 6km from the parent tree site. (Nieuwmeyer 2002 ref.6389 0)
Five allergenic proteins have been detected: 82 kD, 67 kD, 54 kD, 44 kD, and 38 kD (Fountain 1991 ref.4710 6)
The pollen grain is large, and may be responsible for the allergen's low allerginicity.
Pinus pollen allergy has been generally considered to be rare and clinically insignificant. Although Pine pollen is released in large quantities, IgE-sensitisation to it has been found in some studies to be low. (Freeman 1993)(Bousquet 1984) This has been thought to be due to the size of the pollen from this tree. Recent studies from Spain suggest that Pine tree pollen is in actually a significant aeroallergen and should be considered when investigating pollen-allergic individuals. (Marcos 2001 ref.4709 6)
IGE AND IMMUNE:
Hayfever and asthma.
Allergic contact dermatitis (see also: Colophony)
Allergy to pine trees is generally held to be rare and clinically insignificant. Skin test sensitivity to pine pollen antigen was found in 12 of approximately 826 (1.5%) atopic patients in a northern Arizona private allergy practice. (Freeman 1993) An earlier study found that 3.2% of pollen allergic subjects were pine pollen positive (Harris 1985 ref.4445 4)
Allergic alveolitis from Pine sawdust has been reported. (Malmstrom 1999 ref.4418 5)
A 73-year-old man presented with an 8-year history of a dermatitis affecting his face, dorsum of hands, and forearms was found to be positive to colophony and saw-dust samples from four different timbers: Silky Oak, Queensland Hoop Pine, Radiata Pine and Australian red cedar on Patch testing. (Cook 1997 ref.4423 7)
This Spanish study suggests that Pine tree pollen is a significant pollen aeroallergen and should be considered when investigating pollen allergic individuals. In this study, Pinus pollen was shown to constitute one of the most predominant pollens in this area of Spain, in this instance, Pinus pinaster and Pinus radiata. The majority of these patients were monosensitizated to Pinus pollen and suffered from seasonal rhinoconjunctivitis. (Marcos 2001 ref.4709 6) The sensitising Pine pollen will depend on which species of Pine tree is present in the vicinity.
Pinus pollen allergy has been generally considered to be rare and clinically insignificant. Although Pine pollen is released in large quantities, IgE-sensitisation to it has been found to occur in only 1.5% - 3% of atopic patients in a northern Arizona private allergy practice and in French studies. (Freeman 1993 ref.4432 4) (Bousquet 1984 ref.4396 8)
Forestry worker, wood worker
Contrary to the rarity of sensitisation from Pine pollen, workers processing Pine in sawmills showed a very high frequency of IgE sensitisation to the extract of Pine wood dust. This frequency was significantly greater than that of the sensitisation of Oak workers to Oak.(Dutkiewicz 2001) Airborne allergic contact dermatitis from Pine dust has been documented.(Watsky 1997)
Occupational asthma, lung function deficits, and elevated levels of respiratory symptoms in workers exposed to wood dust may occur but may not necessarily be IgE mediated, as other naturally occurring substances in Pine trees may be significant.(Ahman 1995) 11 Reactions to these substances may be IgE-mediated or irritant in nature.
In this study, work-related respiratory complaints among Swedish woodwork teachers was shown to be partially due to specific IgE to a tree, but also due to other mechanisms. (Ahman 1995)
Unknown or Nil
Information supplied from an abridged section of:
Allergy Advisor - Zing Solutions
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