Functional Category
Aerosol propellant.
Applications in Pharmaceutical Formulation
Chlorodifluoroethane is a hydrochlorofluorocarbon (HCFC) aerosol propellant previously used in topical pharmaceutical formulations. However, it is no longer permitted for use in pharmaceutical formulations because of its harmful effects on the environment. It was also generally used in conjunction with difluoroethane to form a propellant blend with a specific gravity of 1. Chlorodifluoroethane was also used in combination with chlorodifluoromethane and hydrocarbon propellants. Chlorodifluoroethane may be used as a vehicle for dispersions and emulsions.
Description
Chlorodifluoroethane is a liquefied gas and exists as a liquid at room temperature when contained under its own vapor pressure, or as a gas when exposed to room temperature and atmospheric pressure. The liquid is practically odorless and colorless. Chlorodifluoroethane is noncorrosive and nonirrit
Stability and Storage Conditions
Chlorodifluoroethane is a nonreactive and stable material. The liquefied gas is stable when used as a propellant and should be stored in a metal cylinder in a cool, dry place.
Incompatibilities
Compatible with the usual ingredients used in the formulation of pharmaceutical aerosols. Chlorodifluoroethane can react vigorously with oxidizing materials
Safety
Chlorodifluoroethane is no longer permitted for use as an aerosol propellant in topical pharmaceutical formulations. It is generally regarded as an essentially nontoxic and nonirritant material. 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: WARNING: Avoid inhalation. Keep away from eyes or other mucous membranes. (Aerosols designed specifically for oral and nasal inhalation need not contain this statement.) WARNING: Do not inhale directly; deliberate inhalation of contents can cause death. or WARNING: Use only as directed; intentional misuse by deliberately concentrating and inhaling the contents can be harmful or fatal. Additionally, the label should contain the following information: WARNING: Contents under pressure. Do not puncture or incinerate container. Do not expose to heat or store at room temperature above 1208F (498C). Keep out of the reach of children. In the USA, the Environmental Protection Agency (EPA) additionally requires the following information on all aerosols containing chlorofluorocarbons as the propellant: WARNING: Contains a chlorofluorocarbon that may harm the public health and environment by reducing ozone in the upper atmosphere