If You Are Sensitive to Bleached Fabric
Try wearing unbleached cotton and linen clothes if you are sensitive to bleached fabric. Sources of these are given below. Unbleached cotton fabric is more flocky than ordinary cotton and can upset you if you are very sensitive to cotton.
If You Are Sensitive to Other Chemicals
If you are generally chemically sensitive, it is better to avoid chemical treatments, such as fire retardants, moth repellents and germicides, as far as possible. Cotton winceyette is often treated and is best avoided.
Dyes rarely cause allergy or sensitivity but a group known to cause problems are mostly chemicals known as the Disperse azo dyes. These are rarely used on cotton, viscose, rayon or wool, but commonly on synthetics. Colour is unfortunately no guide to the chemicals in question. Dyes in nylon stockings and tights are known to cause reactions. You can get dye-free nylons and wearing these may help you to work out if dyes rather than fibres are causing your symptoms. Avoid overprinted fabrics, or T-shirts with placement prints if you are very sensitive. The dyes or fabric inks used in these can be troublesome.
Some mordants are known to sensitise. These are metallic salts used to fasten a dye to a fabric. Chromates (salts of chromium) are known to produce reactions. They are a common cause of occupational dermatitis, having wide industrial uses. If you know you react to chromates, these may be behind unexplained reactions to clothing.
Workwear, such as overalls or uniforms, is often treated with fire retardants, germicides or other protective chemicals. These may be the source of problems.