The present invention provides an inhalable pharmaceutical formulation for preventing and/or treating heavy metal poisoning, said formulation comprising； a chelating agent selected from a group consisting of Ethylene diamine tetraacetic acid (EDTA) and Diethylene triamine pentaacetic acid (DTPA), or its salts, derivatives or mixtures thereof, having particle size in the range of 10 nm to 5000nm； at least one or more of an ingredient selected from 0.03-2% w/w of a surfactant on the weight of the chelating agent； and optionally one or more pharmaceutically acceptable excipients. The pharmaceutical formulation of present invention is suitable for inhalation for used in treating, preventing, or in the management of heavy metal poisoning, including that radioactive materials, particularly those entering the body through the inhalation route. Typically, the mode of administration of pharmaceutical formulation of present invention includes either drug aerosols released through nebulization process from fluid formulations or through dry aerosols using Dry Powder Inhalation (DPI) methodology.
