Disinfectants are chemical agents used to disinfect inanimate objects and surfaces. Examples of disinfectants include iodine solution, copper sulfate, ozone, and chlorine gas. Antiseptics are chemical agents applied to living tissues to prevent infection. Antiseptics are generally less toxic than disinfectants because they must not cause too much damage to the host living tissue. Examples of antiseptics include iodine, 70% ethanol and 3% hydrogen peroxide. The concentration of a chemical agent can determine if it can be used as a disinfectant or an antiseptic. In the case of iodine, weaker solutions of iodine can be used for antiseptic purposes, while stronger concentrations should be used as a disinfectant.