title: The role of international environmental agreements in metered-dose inhaler technology changes.
abstract: Introduced in the 1950s, metered dose inhalers (MDIs) became a revolutionary way to deliver medication directly to the lungs of patients with asthma and chronic obstructive pulmonary disease. Since their initial introduction, MDIs have used chlorofluorocarbons to propel the medication out of the canister into a patient's lungs. This article presents an overview of the global transition away from the use of chlorofluorocarbon propellants in MDIs to non-ozone-depleting substitutes including hydrofluoroalkane (outside of the pharmaceutical industry and in the context of Montreal Protocol and Kyoto Protocol discussions, these gases are referred to as hydrofluorocarbons; hydrofluoroalkane-134a, for example, is referred to as hydrofluorocarbon-134a) propellants, in accordance with the terms of the international environmental agreement the Montreal Protocol on substances that deplete the ozone layer (the Montreal Protocol). This article will also describe the environmental characteristics of chlorofluorocarbons and hydrofluoroalkanes when they are used as MDI propellants. Finally, the article will review key provisions of the pending Kyoto Protocol to the United Nations Framework Convention on Climate Change (the Kyoto Protocol) that may affect the future of hydrofluoroalkanes.
authors.affiliation: United States Environmental Protection Agency, Washington, DC.
authors.forename: R
authors.initials: R
authors.lastname: Forte
authors.forename: C
authors.initials: C
authors.lastname: Dibble
mesh_terms: D000280:Administration, Inhalation; D017402:Chlorofluorocarbons / Q000008:administration & dosage; D005740:Gases; D017752:Greenhouse Effect; D006801:Humans; D007391:International Cooperation; D009330:Nebulizers and Vaporizers; D014481:United States; D014484:United States Environmental Protection Agency; D014486:United States Food and Drug Administration
chemical_list: D017402:Chlorofluorocarbons; D005740:Gases