ABOUT DUST MITE!
Introduction
House-dust mites are those species of the family Pyroglyphidae that are regularly found throughout the world – Dermatophagoides pteronyssinus, Dermatophagoides farinae and Euroqlyphus maynei. These species constitute 90-100% of the mite population found in mattresses and 70-90% found in carpets and furniture dust.
Over two million Australians suffer from asthma.
Research indicates:
- Asthma is one of Australia's most serious health concerns, costing the community over $720 million a year. It affects 2 in 5 primary aged children, 1 in 7 adolescents and 1 in 10 adults.
- Asthma is largely an allergic disease. 30-40% of Australians are allergic to dust mites and their faeces, household pets, pollens and/or mould.
- These allergens are major triggers of asthma and allergies like eczema and rhinitis (itchy eyes, sneezing, blocked & runny nose.)
- Children who are allergic to dust mites are up to twenty times more likely to have asthma than non-allergic children.
Dust mites are a major cause of asthma and allergies.
Dust mites are tiny scavengers (about half the size of a full stop) that thrive in warm, dark, humid conditions and live mainly on discarded human and animal skin & mould.
- We are most exposed to dust mites in the bedroom as it provides the ideal conditions of warmth, humidity and food. Dust mites thrive in mattresses, quilts, pillows, blankets and doonas, underlays, carpets and rugs, upholstered furniture, curtains, clothes and soft toys - infesting the bedroomin millions.
- it is actually their droppings which trigger the symptons of asthma and allergies like eczema and rhinitis. Dust mite droppings contain a powerful enzyme to break down food which, when breathed in, also breaks down the protective lining of our lungs, nasal passages and eyes.
Mould and animals are also common allergens.
- Mould/fungus can grow anywhere but favours damp, poorly ventilated areas such as bathrooms, refrigerators and wardrobes.
- Household pets like dogs, birds, rabbits, guinea pigs, mice and especially cats, transfer allergens to furnishings and clothing.
- Animal allergens also accumulate in carpets, mattresses, cushions and curtains as well as horizontal surfaces.
Sheepskins and wool pile underlays are commonly used for both residential and medical bedding because of their superior comfort and cushioning attributes. Whilst medical sheepskins are manufactured such that they are able to be washed at a temperature of 80ºC, well over the 55ºC required to kill dust mites, manufacturers recommend that domestic sheepskins and wool underlays be washed at luke-warm temperatures (35-45°C). This will remove the majority of allergen present, but is unlikely to kill mites.
One approach to overcoming this shortfall is to introduce an acaricide as a wash additive or in a detergent to increase mite mortality during washing. A number of products, which are claimed to do so, are currently on the market. However these products contain Benzyl Benzoate, which is a chemical pesticide and therefore not as appealing to the consumer as a washing product containing an essential oil.
Tests carried out by Lindy G McDonald BSc(Hons) & Euan Tovey PhD demonstrated the effectiveness of Benzyl Benzoate and some essential plant oils as laundry additives for killing house dust mite. These tests showed Benzyl Benzoate killed all the mites and the essential plant oils killed 80% of the dust mites. However the concentration of the acaricide was relatively high at 250ml per 30lt water and the wash time 30 minutes. In real terms these concentrations would prove to be relatively expensive and the odour very concentrated. The relatively long wash time would not be ideal for fibres such as wool and sheepskin. Washing at high temperature above 55°C will kill house-dust mite however some fibres shrink or are damaged at these temperatures.
Facts:
- Dry cleaning kills dust mite but does not remove allergen
- Washing at high temperature kills dust mite and removes allergen but is not suitable for some fibres
- Washing at low temperatures, which is preferred by most housewives, does not kill dust mite but removes allergen
For more information on House Dustmite go to House Dustmite Information Website.