Chlorinated hydrocarbons are a group of chemical compounds that contain carbon, hydrogen, and chlorine atoms. They are often used in industrial applications, such as solvents, pesticides, and refrigerants. Some common examples include dichloromethane and trichloroethylene. While they can be effective in their uses, many chlorinated hydrocarbons are harmful to the environment and human health. These compounds can persist in the environment for a long time, leading to pollution in soil and water. Exposure to chlorinated hydrocarbons can cause various health issues, including respiratory problems and increased cancer risk. Therefore, it's important to handle them with care and seek safer alternatives when possible.