Posts Tagged ‘soft toys’

Because house-dust mites are a major source of allergic reactions they have been studied intensively, and various ways of killing them devised. But simply killing the mites is not enough. Their allergens will remain, and continue to cause allergic reactions for years. The allergens have to be either removed or inactivated — that is, changed chemically so that they are no longer recognised by the immune system.
Tackling dust mite is easier if you know certain key facts:
1 Dust mites prefer humid conditions. They do not drink, but absorb water from the air. When the relative humidity falls below 50%, the mites gradually dry out and are killed.
2 Mites feed on our skin scales, but only if they have been broken down first by moulds. High humidity (70-90% relative humidity) is a particular problem, for anyone with an allergy to house-dust mites, because it favours the mould that suits dust mites best.
3 Dust mites live inside mattresses, pillows, upholstery, cushions and soft toys. The allergens are blasted out when you settle into an armchair, get into bed, or turn over in the night.
This is when you inhale the biggest dose of allergen, or get the maximum dose to your skin. Carpets also contain dust mites, but the numbers are generally lower.
4 Dust-mite allergen is relatively heavy, compared to cat or mould allergens for example. Little of it floats around in the air, and the most significant exposure is inhaling it close to the source — from a pillow, mattress or teddy bear. This is why air filters are of little value for anyone with dust-mite allergy.
5 Dust mites are everywhere, and are carried around in clothing. Even if you could eliminate all the mites from your house, new ones would soon appear. A new mattress will usually be colonised by dust mites within four months.
The size of the allergen particles
The droppings of the dust mite, not the mites themselves, are the main cause of symptoms. The droppings are 4-20 microns in size, but they can crumble into fragments of 1-3 microns, and the tiniest bits are only 0.5 microns across. The pores of mite-proof covers (which really means mite-allergen-proof) should be less than one micron across, and preferably less than 0.5 microns. Dust masks (see p. 109) should also filter out particles of this size to be effective. The mites themselves are much bigger, 200-300 microns long, (A micron is one thousandth of a millimetre.)
The basics of mite warfare
• A temperature just above boiling point kills dust mites and inactivates Der pl, which is the troublesome allergen for most asthmatics. However Der p2, the other mite allergen, is not affected by heat. (Note that the carpet treatments advertised as ’steam cleaning’ generally just use hot soapy water, not steam. Because they leave the carpet very damp, they can increase the numbers of dust mites.)
• Washing with detergent at 55′C (130′1 or above (i.e. a 60′C wash cycle) kills mites and removes the allergen.
• Cooler washes will not kill mites, but will remove the allergen. This can be useful if the mites have already been killed by some other means. Regular cool washes of clothing or sheets will also remove human skin scales, reducing the mites’ food supply. (This is beneficial if you have eczema, because flaking skin adds to the problem by giving dust mites even more to eat.)
• You can buy mite-killing substances (see p. 255) to add to cooler washes, so that the mites are killed - the chemicals are rinsed out at the end of the wash, so are pretty safe.
• Dry-cleaning kills mites and it removes some of the allergen, but the amount removed is variable (20-70%).
• Freezing for more than six hours kills mites. Three hours’ strong direct sunlight in dry air will kill mites living in rugs and blankets. Neither treatment removes allergen.
• Mites hang on to the carpet fibres when the vacuum cleaner passes overhead, and about 65% of them remain afterwards. An ordinary vacuum cleaner sprays mite allergen into the air as it goes. The amount in the air - and therefore available to be inhaled - is three times higher after vacuuming.
Combating mites
Bear in mind that mites are the enemy - not dust itself. A house may be thick with dust but, because the windows are open a lot and the air is dry, it will have few mites. Another house may look perfectly clean, but be seething with mites because it is thoroughly draught-proofed, warm and slightly humid. The mites will be thriving in the carpets, beds and upholstery. Vacuuming and dusting every day, if done with an ordinary type of vacuum cleaner and a dry duster, will stir up the allergens and ensure that the air is full of them. So a person with mite allergy would feel far worse in the apparently very clean house than in the dusty one.
One crucial aspect of a mite-reduction programme is making the air drier - see p. 119 - so that mites no longer flourish.
Most of the other measures - described below - will involve stirring up dust-mite allergens, so the allergic person should not do the work, nor be in the house (see p. 109).
Too dry or too moist?
It is a well-established fact that the air in most modern houses is too humid, encouraging dust mites and moulds. Yet many people fit humidifiers because they believe that the air is ‘too dry’ and that this irritates the nose. Some very good scientific studies have shown it is indoor pollutants plus overheating that is the problem here, not dryness - even very dry air is not irritating as long as it is clean. Should your nose feel dry and ticklish, try to reduce indoor pollution (see pp. 128-9).
It is true that during an asthma attack, dry air does make matters worse, and very moist air helps. Inhaling steam from a bowl of hot water can be used to ease the attack.
The bed
Begin with the bed because this is the main exposure zone. A Danish study showed that just fitting mite-allergen-proof covers to the mattresses and pillows of dust-allergic children worked well. After a year the children had much less asthma at night, used half as much inhaled steroid, and gave better peak-flow readings.
The best approach is to buy a new mattress and new pillows before putting anti-mite coverings on them. These covers keep skin scales and mites out, which should prevent a new mattress or pillow becoming recolonised. The modern covers have tiny pores which allow perspiration to evaporate - this makes them comfortable to sleep on.
These pores are small enough (see box on p. 114) to keep any mite allergens inside, so they will also work with an old mattress, keeping the existing allergen inside. But the mites themselves will also thrive inside (there’s enough old skin there to keep them in business for years) and there is always the risk that, if a small tear develops, the stores of allergen in the mattress will come pouring out again. So start with a new mattress if you can.
Another possible option is to arrange for a contractor to heat-treat the bed, the mattress and all bedding. This is a new specialist treatment (see p. 255), where the bed is enclosed in a plastic tent and heated to very high temperatures. It is designed to kill all mites, even those right inside the mattress, and inactivate the allergen. (The contractor can also do your living room suite.)
If the covers are for a small child, check with the manufacturer that they pose no threat of suffocation. Mattresses and bedding with built-in covers may be safer.
Buy a new duvet (or wash or dry-clean your existing one) and put an anti-mite cover on it. Alternatively, buy a duvet and pillow that can be washed at 60′C (130′F), and wash them once a month. You must have the use of a tumble dryer, because mites will flourish if bedding is not completely dry.
An upholstered bed base will have its own (much smaller) population of mites. Buy a simple wooden or metal bed frame if possible. Or you could enclose the upholstered base in a mite-proof cover, or in plastic sheeting completely sealed with heavy-duty tape.
Wash all sheets and blankets at 60°C or more, or have blankets dry-cleaned – or buy new ones. From now on, wash sheets once a week and blankets once every two weeks.
Get rid of any other bedding such as patchwork quilts or fleecy underblankets. Alternatively, you can wash or dry-clean them regularly.
Electric blankets can be cleared of mites by washing them, and are very useful in keeping the bed free from moisture. This prevents mites from setting up home in the outer surface of your new mite-proof covers, so that you don’t need to wash the covers, sheets and underblankets so frequently. Leave the electric blanket on at a high setting, with the bed made, for at least twelve hours (check that there is no fire risk first). Note that some mite-proof covers might be damaged by this procedure – check with the manufacturer. If you have not yet purchased mite-proof covers, there are some made from Egyptian cotton which can tolerate this level of heat without damage (see p. 255).
Children’s beds and toys
Where children share a room, all the beds and bedding should be dealt with. Even then, an asthmatic child should never sleep in the lower half of a bunk bed, because mite allergens will shower down from the bed above.
Ali soft toys should spend at least six hours in the freezer once a week, to kill the mites. The first time, wash the toys
immediately afterwards to remove any existing allergen and dry thoroughly in a tumble dryer.
A hot wash, or the freezing/washing treatment, should also be used for ‘comfort blankets’, dressing-up clothes, dolls’ clothes and any other fabric items.
Sheepskins, sometimes used for babies’ cots, especial,. New Zealand and Australia, contain huge amounts of dust-mite allergen. It is advisable to discard these.
The next steps
Clothing is often full of mites, especially sweaters, coats and woollen trousers. Dry-clean all such items, or wash using a m –e-killing wash, then store them in a well-heated place so that they are always very dry.
Dandruff consists of skin flakes, and may help to feed mites Using an anti-dandruff shampoo may help. Semen also gives mites nourishment.
From now on, be careful about exposing your airways to dust. Get someone else to empty the vacuum cleaner bag – and they should, of course, do it outdoors. If you are stripping wallpaper, wash it down first to remove dust. Moving house, going into the attic, spring cleaning, turning out cupboards or moving furniture should all be avoided – unless you have a good mask on.
Do not use fan-heaters or convector heaters which churn up mite allergens from the carpet. Seal off any hot-air ducts from centralised heating systems, as these blow mite allergens around the room.
If possible, invest in a vacuum cleaner that keeps in all the allergens, or vents them outside, rather than spraying them out into the air. Make sure that the vacuum cleaner you buy really
What about sprays?
Chemicals that kill mites (known collectively as acaricides) are sometimes useful but have various limitations. They do not penetrate inside upholstered furniture, cushions or mattresses, so make little difference to the total population of dust mites. Even on carpets, sprays won’t reach most of the mites unless you rub the spray in really hard. (And ‘anti-mite’ carpet shampoos are completely ineffective.)
The safest chemical is benzyl benzoate — so safe that it is used directly on the skin for treating scabies infections. It can cause skin irritation at these doses, but rarely does so at the concentrations used in anti-mite sprays.
However, the idea of constant spraying, over a period of months or years, is worrying. Doctors generally advise against spraying bedding, and carpets or furniture where babies or small children play, to avoid close and prolonged contact with the spray residue.
Even more alarming are sprays containing a pyrethroid (pyrethrum) compound. The latter is derived from a plant and is therefore sold as ‘natural’, but pyrethroids are potentially toxic with prolonged exposure, and they quite often provoke allergic reactions too. They should definitely be avoided.
Sprays that inactivate allergen (rather than killing mites) sometimes have their uses. There are two kinds and both should work against a variety of allergens, not just dust mite. Polysaccharide sprays stick the allergen particles together, so that they don’t float about and get inhaled. Tannic acid sprays change the allergen chemically, making it non-allergenic. Because tannic acid is found in tea it is assumed to be harmless, but the sprays available vary a lot and often contain many impurities, so it is hard to be sure about their long-term safety. Don’t use these sprays on bedding.
Carpets and bedding covers with built-in pesticide are also on sale, but are probably best avoided.
does its job well – a lot of machines now claim to be ‘allergy’ vacuum cleaners but they are not all equally good. Very few have been adequately tested (see p. 255). Alternatively, cover the bed with a clean sheet and open the windows whenever you vacuum, leaving them open for half an hour afterwards. After closing the windows, allow the dust to settle for another half hour, then carefully remove the dust-cover from the bed.
For dusting, use a damp cloth and add a few drops of eucalyptus oil which deters mites. Alternatively, use a special anti-mite duster with an electrostatic charge that holds the dust.
Above all, keep the moisture levels in your house down. Ultimately, this is the key to eliminating dust mite. Look at p. 119 and check you are doing everything possible.
The bedroom in particular should be kept dry. Air your bedroom whenever it’s dry and sunny. Remove pot plants and fish tanks. Don’t dry clothes in the room and don’t shampoo the carpet. Avoid using Calor gas heaters, as these produce a lot of moisture. If your bedroom has an en suite shower, fit a powerful extractor fan, or open a window wide during and after showers – or just stop using this shower. En suite basins may also generate moist air.
Do you need to do more?
Give it some time before deciding if you have done enough. In one study, it took eight months for the full benefits of an anti-mite campaign to be seen.
If you are still not as much improved as you hoped, then you could try a more drastic mite-elimination programme.
Thoroughly clean the bedroom, getting rid of any dust along skirting boards or picture rails, on top of wardrobes or behind furniture. Remove anything stored under the bed, so that vacuuming is easier in future. During this cleaning operation, completely cover the bed.
Get rid of the bathroom carpet, if you have one. In the bedroom, either remove the carpet or buy a special anti-mite steam cleaner that kills mites in the carpet and inactivates the allergen. To work properly, the device must produce steam at a temperature above boiling point, by means of high pressure. Make sure you are buying the right kind of device.
If you take out the carpet, you will need to mop the floor, with a wet or oiled mop, several times a week, as the dust will quickly build up, and is easily made airborne from an uncarpeted floor. One of the advantages of carpet is that it ‘holds’ dust at floor level.
Wash the curtains, or dry-clean them, or replace them with blinds of a kind that can be easily wet-dusted. If you have bought an anti-mite steam cleaner for the carpet, use this on the curtains every 2-3 weeks.
Remove dirty clothes from the bedroom, clean out drawers and shelves, and dry them thoroughly. Only store freshly laundered clothes in the room.
Remove all upholstered items from the bedroom, such as padded headboards, cushions, armchairs, or stools with padded seats. Draught excluders, fabric lampshades and anything covered in velvet should also go.
A different approach
If you are even more allergic to housework than you are to dust mites, consider buying a really powerful dehumidifier, designed for killing mites. This makes the air too dry to breathe (its relative humidity or RH goes down to 25%), so you leave it on in the bedroom during the day, with the bedroom door closed. You must eliminate all sources of moisture that will counteract the dehumidifier, and have fairly tight seals around your windows and doors for it to work. In the evening, turn the dehumidifier off and leave the bedroom door open for an hour or so before going to bed.
Of course, all the allergen which was already there in the bed, carpet, curtains, clothes and soft toys will still be present. You need to either eliminate or inactivate this allergen using the methods described above. But once you have got your daily dehumidifier routine going, you do not need to rewash everything regularly because mites will be a thing of the past, so no new stocks of allergen will be produced.
The rest of the house
A completely mite-free house is hard to achieve, but if you are determined, you can come close. Everything so far described for the bedroom, such as reducing moisture in the air, and dealing with carpets and curtains, is applicable to the rest of the house.
The exception – and the toughest nut to crack – is the upholstered furniture in the living room. Fixed upholstery (i.e. everything other than removable cushions) is a safe haven for mites that is especially hard to deal with.
One option is to give all such furniture a specialist heat-treatment, if this is available locally (see p. 115). The mites inside will be killed, and the allergen inactivated. If you drastically reduce moisture levels at the same time – with a powerful dehumidifier used at night, perhaps – you should avoid serious reinfestation.
Alternatively, you could replace all your existing upholstered furniture with leather-covered or vinyl-covered furniture. Both are impenetrable to mites. Furniture made of wood or bamboo with loose cushions and no fixed upholstery can also work. Fit the cushions with tailor-made mite-proof covers (hard to get, but ask around) when new. Then put the ordinary covers on top, and wash these regularly.