Chlorofluorocarbon propellant

Some physicians recommend epinephrine metered-dose inhalers as an alternative to epinephrine autoinjectors. While a few inhalations might relieve mild or moderate respiratory symptoms, for relief of life-threatening airway obstruction or shock, adults need to inhale 20-30 puffs and children need to inhale 10-20 puffs, which is hard to do [35]. Epinephrine metered-dose inhalers contain chlorofluorocarbon propellants. For environmental reasons, they might not be manufactured in the future. 

CFC, chlorofluorocarbon propellant HFA, hydrofluoroalkane propellant MDI, metered-dose inhaler. 

Salmeterol xinafoate inhalation aerosol contains salmeterol xinafoate as the racemic form of the 1-hydroxyl-naphthoic acid salt of salmeterol. It is a pressurized, metered-dose aerosol unit for oral inhalation. It contains a microcrystalline suspension of salmeterol xinafoate in a mixture of two chlorofluorocarbon propellants (trichlorofluoromethane and dichlorodifluoromethane)... 

Chlorofluorocarbon (CFCs). Prior to 1978 most aerosol products contained chlorofluorocarbon propellants. Since that time, the use of chlorinated fluorocarbons for aerosols has been seriously curtailed. These compounds have been implicated in the depeletion of the ozone (qv) layer and are considered to be greenhouse gases (see Am pollution Atmospheric modeling). 

The multidose pressurized aerosols using chlorofluorocarbon propellants have been widely used. 

Wysowski DK, Swann J. Use of inhalant medications with and without chlorofluorocarbon propellants in the United States, 1996-2000. J Allergy Clin Immunol 2002 110(l) 51-3. 

Deliberate inhalation of excessive quantities of chlorofluorocarbon propellant may result in death, and the following warning statements must appear on the label of all aerosols ... 

Blends of trichloromonofluoromethane and dichlorodifluoromethane (propellant 11/12) or propellant 11/114/12 produce vapor pressures of 103 84 kPa (15-70 psig) at 21°C, which adequately cover the range of pressures required to produce the proper particle-size distribution for satisfactory aerosol products. Trichloromonofluoromethane is unique among the chlorofluorocarbon propellants in that it is a liquid at room temperature and atmospheric pressure and can be used to prepare a slurry with insoluble medicinal agents. 

Chlorofluorocarbon propellants are nonreactive and stable at temperatures up to 550°C. The liquefied gas is stable when used as a propellant and should be stored in a metal cylinder in a cool, dry place. 

Table II Selected typical properties for chlorofluorocarbon propellants.

The stoichiometry of some of the solvates is unusual. Fludrocortisone pentanol solvate, for example, contains 1.1 molecules of pentanol for each steroid molecule, and its ethyl acetate solvate contains 0.5 molecules of ethyl acetate per steroid molecule. A succinylsulfathiazole solvate appears to have 0.9 moles of pentanol per mole of dmg. Beclometasone dipropionate forms solvates with chlorofluorocarbon propellants. 

A different result, however, was reached in United States v. Falcon Safety Products (D.N.J. January 27,1981). In that case, the District Court upheld the Commission s use of Section 27(e) to require a warning for all aerosolized consumer products containing chlorofluorocarbon propellants. The Commission s warning, which was similar to warnings adopted by the Food and Drug Administration and the Environmental Protection Agency for products within their jurisdictions, stated as follows ... 

Flunisolide nasal solution is available in an aqueous solubilized form, which delivers 25 pg per spray. The total daily adult dose for flunisolide from the nasal spray is 200 to 400 pg. Flunisolide inhalation aerosol for pulmonary delivery is a microcrystalline suspension in a chlorofluorocarbon propellant that delivers 250 pg per metered spray. The total daily adult inhalation dose for flunisolide is 1,000 pg. Doses exceeding 2,000 pg/day need to be monitored for FIFA suppression. 

Budesonide nasal aerosol is supplied as a micronized suspension using a chlorofluorocarbon propellant, which delivers 32 pg from the nasal adapter supplied per metered spray. The total daily adult dose for budesonide is 256 pg. Budesonide powder for pulmonary inhalation uses micronized dry powder in a turboinhaler (DPI) that delivers 200 pg per metered sprayed. The total daily adult dose for budesonide from the DPI is 200 to 800 pg. Full benefit is attained in approximately 1 to 2 weeks. 

Hydrocarbon solvents, especially chlorinated hydrocarbons, and chlorofluorocarbon propellants all enhance the sensitivity of the myocardium to catecholamine-induced dysrhythmias. 

TSCA also contains provisions for EPA to control or ban chemicals which it considers to pose an unreasonable risk to human health or to the environment. Such action may range from requiring a warning label to imposing a complete ban on production, import and use. As of mid-1992, action under this Section of TSCA had been limited to polychlorinated biphenyls, chlorofluorocarbon propellants, asbestos in schools and dioxin (TCDD) wastes. 

Bithionol Cattle material Chlorofluorocarbon propellants Prohibited Prohibited Prohibited Photocontact sensitization... 

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