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Inhalent sensitivities
This group includes pollens, moulds, animal dander and housedust mites.
Housedust Mites are probably the most important inhaled allergen; reducing exposure to them is the most fundamental aspect of allergen avoidance. They are found in large numbers in most houses in the UK; they require a food source (shed skin scales), warmth, and humidity to survive.
Skin scales are found in abundance in bedding, soft furnishings and carpets. Each night we warm up our beds as we sleep, shed skin and provide moisture through perspiration and breathing (roughly a pint per person per night); therefore high levels of mites are found in bedclothes, mattresses and pillows. Each mite passes very small faecal pellets (about 30 microns); these are extremely dry as the housedust mite needs to conserve as much moisture as possible. These pellets fragment easily into particles, which become airborne very easily, and remain airborne for many hours. They are of a size that our defences find most difficult to keep out of our airways, and they are therefore easily inhaled. As they land on the surface of the airways they set up an immune response; because they will act as a repeated stimulus to the immune system, in the susceptible patient allergy may well develop.
Housedust mite exposure should be reduced even if you do not think it is a particular problem – almost every allergic patient is allergic to them, and this puts a constant ‘load’ on the immune system.
There are several ways of approaching the control of housedust mite exposure:-
- The most important area to tackle is the bed. Wash bedding regularly. Mites in bedclothes will be killed if you can hot wash them (60oC and above). Although normal cool washing does not kill mites, it does wash out the allergic component of the pellets that causes the problem, and it will be some time before the levels rise again. Pillows are supposed to be washable but in practice it can be difficult getting them dry, and mattresses can’t be washed at all. Therefore pillows and mattresses hold high levels of mites and every night their pellets are breathed in as we sleep. They should be covered with a special ‘allergy’ breathable barrier cover if possible. The duvet should also be covered in the same way unless it is washable and is regularly washed. Mattresses on slatted bases, which allow good air circulation, are an advantage if possible.
- Kill them with high temperature steam cleaning of carpets, mattresses etc (high-temp steam leaves things dry rather than wet); or by freezing (e.g. pillows, soft toys).
- Increase ventilation to lower humidity (i.e. have windows open as much as possible). One of the reasons for the increase in housedust mite problems in recent decades is poor ventilation leading to higher humidity, which encourages mite growth. Reducing humidity levels kill mites, and as it also controls mould growth and reduces indoor air pollution (often worse than outdoor pollution).
- The best option is a good air filter (and a dehumidifier if the house is particularly damp). There are many air filters on the market that will trap larger particles such as whole pollen grains and mite pellets, but fragmented pellets and pollens, and some mould spores, are of a size (up to one micron) which most easily get through our defences. Up to 95% of the airborne particles in a room will be of this size, and they are also the most difficult particles for an air filter to remove. Filters, which are specifically designed to remove these most difficult particles, are called HEPA filters, and these are the best ones to buy.
- Filter vacuum cleaners – the small size of the most troublesome particles means that they pass straight through the coarse filter and dust bag of a normal cleaner and are blown around the room (thus many dust allergic people are worse after vacuuming). Simple measures include getting someone else to vacuum, opening windows wide during vacuuming, and not doing it so often – damp dust instead (but not with a cloth that is too wet, or humidity will rise). Ideally an old vacuum cleaner should be replaced with one that is designed to effectively trap even the sub-micron particles which cause the problems. There are a range of options, from expensive but very effective purpose built machines, through to standard models fitted with special microfilters, to filter material which can be added to your existing vacuum cleaner if you can’t afford a new one. Whichever type you choose, you should be sure that the filter vacuum effectively removes particles down to half-a-micron or so. A more powerful machine will suck up more dust and therefore steadily reduce the ‘reservoir’ of housedust mite left in furnishings.
Grass pollen is commonly considered; tree and weed pollens are often ignored but as each has it’s own season ranging from January (Hazel) to October (Dandelion). Air filters are effective indoors (pollens are relatively large particles, although fragments are obviously much smaller). Filter vacuum cleaners will trap pollens.
Mould spores are usually ignored but are potent allergens – very few allergic patients are not mould sensitive. Different moulds spore at different seasons, so mould sensitivity (as with pollens) can lead to year long symptoms, usually worse in spring and particularly autumn, in damp weather, when raining or snowing, and in gardens, around compost heaps, and when cutting grass. Measures to reduce humidity, increase ventilation, and good air filters will help tackle mould sensitivity, as may avoiding ‘mouldy’ foods such as blue cheeses, mushrooms and yeasts.
If you have a damp house, particularly where mould is visible on walls and windowsills, it is important to determine the cause and tackle it (either structural faults, or condensation due to inadequate heating or poor ventilation)
Animals
The allergic effect of dogs is due to their dander (material from the fur and skin); in cats the saliva is the problem. Birds’ feathers can cause problems directly, or due to mites living in the feathers. No allergic person should allow their pets access to the whole house, and especially not the bedroom. Restrict them to one area and keep it clean. Filter vacuum cleaners and good air filters will help keep the load down, as will regular washing of dogs (and some cats will also tolerate being washed). High temperature steam cleaning is effective in removing the ‘reservoir’ of allergen in the carpets.
Chemicals
Some chemicals are known to cause allergy-type problems directly – in other words, you start to react to them just like foods and inhaled allergens. The reactions are often quite rapid and fairly severe because chemicals are absorbed into the body much more quickly than foods etc. However any chemical that we inhale or ingest has to be eliminated from the body through our detoxification pathways; these often fail to function adequately in people with immune system problems. The same detox pathways that get rid of chemicals also have to deal with breakdown products from reactions to foods etc. These pathways use vitamins, minerals and proteins to work; the more you react, the harder the pathways work, and the more vitamins and minerals they use. At the same time, people who are allergic to foods tend not to absorb vitamins and minerals from their diet very well. If you become deficient in vitamins and minerals then the detox pathways can’t work effectively, allowing chemicals to build up in the system. Therefore even low levels of chemicals, which would not affect a ‘normal’ person, affect many allergic people.
Reducing the load of chemicals to which we are exposed each day is therefore an important aspect to consider. Not only should you try and avoid chemicals to which you react, but you also need to reduce as far as possible the use of all chemicals in the home, in order to relieve the load on the immune system and detox pathways. So, ideally, everyone in the house needs to do the following:
- DON’T SMOKE or allow smoking in the house; if someone in your house just won’t give up, ask them to only smoke in one room and get a good air filter in there.
- Don’t use perfume or hairspray.
- Switch to un-perfumed deodorants; use sticks/roll-on’s, not sprays (or ideally, nothing)
- Use fragrance free shampoo and conditioner.
- Use a ‘cleaner’ toothpaste, ie homeopathic, herbal, baking soda (patient only).
- Don’t use air fresheners, carpet powder cleaners, scented vacuum bags.
- Use oxygen bleaches, not chlorine bleach. Borax can be put down toilet bowls, and for soaking clothes.
- Cut down on the use of strong smelling disinfectants. Most people use disinfectants when they only need to clean with soap and water. When a disinfectant is needed use a non-taint, safer type such as Dettox.
- Switch to an un-perfumed soap powder of the ‘sensitive skin’ type and don’t use fabric conditioners at all.
- Cut down on the use of furniture polishes and spray cleaners; use pump sprays or tins rather than aerosols (or ideally just damp-dust).
- Half-used tins of paint, brush cleaner etc. should not be kept under the sink. Eventually the paint dries out in the tin – where does the solvent go? into the air in your house!
In summary, everyone in the house needs to stop using any chemical that is not necessary. Where products do still need to be used, they should be fragrance-free, non-aerosol versions.