Dust - Domestic Dust and Humans

Domestic Dust and Humans

Dust may worsen hay fever. Circulating outdoor air through a house by keeping doors and windows open, or at least slightly ajar, may reduce the risk of hay fever-causing dust. In colder climates, occupants seal even the smallest air gaps, and eliminate outside fresh air circulating inside the house. So it is essential to manage dust and airflow.

House dust mites are ubiquitous everywhere humans live indoors. Positive tests for dust mite allergies are extremely common among people with asthma. Dust mites are microscopic arachnids whose primary food is dead human skin cells. They do not actually live on people, though. It is probably not possible to entirely eradicate them. They and their feces and other allergens they produce are major constituents of house dust, but because they are so heavy they are not long suspended in the air. They generally are on the floor and other surfaces, until disturbed (by walking, for example). Sources suggest it could take somewhere between 20 minutes and 2 hours for them to settle back down out of the air. Dust mites are a nesting species that prefer a dark, warm and humid climate, and they therefore flourish in mattresses, bedding, upholstered furniture, and carpets. Their feces include enzymes that are released upon contact with a moist surface, as happens when a person breathes it in, and these enzymes actually kill cells within the human body. Sources suggest that house dust mites did not become a problem until humans began to use textiles, such as western style blankets and clothing.

Alternatively, the hygiene hypothesis posits that the modern obsession with cleanliness is as much a problem as house dust mites. The hygiene hypothesis argues that our lack of prior pathogenic exposure may in fact encourage the development of ailments including hay fever and asthma.