Itﾒs essential that you use good practice when you store, handle or dispose of waste oils, especially those that are classed as hazardous or special waste. There are many types of oil and their properties, which may have changed during use, dictate how they are classed when they become waste. The most common waste oils, derived from fuels or lubricants, originally come from petroleum oil, sometimes known as mineral oils. Many lubricants may also contain synthetic components. Waste oil is harmful to the environment and some, for example used engine oils, may cause cancer, so it needs to be managed carefully. You may need to account for Environmental Health and Safety guidance as well as the environment.