Toxicological properties of chlorinated, aliphatic hydrocarbon solvents are reviewed. A case of an 18 year old worker overcome while digging outside a chemical company building is presented as a typical solvent poisoning. The patient presented unconscious, with low blood pressure and slow pulse characteristic of central nervous system (CNS) depression. Identification of the solvents inhaled was performed through breath sampling. Characteristics of the seven chlorinated hydrocarbon solvents commonly encountered in emergency rooms or industrial settings are described. They are: methylene-chloride (75092), 1,1,1-trichloroethane (71556), trichloroethylene (79016), tetrachloroethylene (127184), ethylene-dichloride (75354), carbon-tetrachloride (56235), and chloroform (67663). These solvents are colorless liquids and very volatile. Each possesses a distinctive odor like chloroform and can be absorbed through the lungs, gastrointestinal tract, or the skin. Signs and symptoms of acute overexposure (in order of increasing severity) are lightheadedness, dizziness, lack of fine coordination, lethargy, mental dullness, drunkenness, unconsciousness, hypotension, respiratory arrest, or anesthetic death. Toxicity, uses, and potential dangers of each solvent are discussed. Emergency treatment for overexposure is described. Trichloroethylene, tetrachloroethylene, and ethylene-dichloride have the potential to injure the liver or kidneys. The author concludes that medical surveillance is warranted following exposure to these solvents.