In an article published in the New York Times in 1980, Ralph Blumenthal highlighted government reports of the multiple health hazards supposedly present in modern American homes. ‘Home sweet home it may be,’ he wrote evocatively, ‘but the coziest nest can mask a household of hazards.’1 According to Blumenthal and other commentators, the indoor environment now contained a range of allergens, poisonous liquids, and toxic fumes that were responsible for making modern populations ill. As many contemporary clinicians were aware, the dangers of the domestic environment were particularly evident in allergy sufferers; hot and humid, carpeted and well-insulated homes provided an ideal breeding ground for house dust mites, which were known to be potent triggers of attacks of asthma, eczema and allergic rhinitis. According to some physicians, greater exposure to domestic allergens was a major factor in the explosion of allergies in most developed countries after the Second World War.2