House Dust Stirs Up Problems With Asthma Drugshttp://articles.mercola.com/sites/articles/archive/2005/12/29/house-dust-stirs-up-problems-with-asthma-drugs.aspxThe first nationwide sampling of house dust has revealed that exposure to household endotoxin levels poses a definite risk for asthma. Dust, Pets, Humidifiers Indoor sources of endotoxins include dust, pets, humidifiers, pests, and outdoor air. Past studiesenCommunityServer 2008.5 SP1 (Build: 31106.3070)