Correction fluid the Montreal Protocol on Substances That Deplete the Ozone Layer, and then the slightly safer trichloroethylene. Thinners currently used with correction fluid include bromopropane. Because it contains organic solvents (volatile organic compounds), unused correction fluid thickens over time as volatile solvents escape into the air. It can become too thick to use, and sometimes completely solidifies. Therefore, some manufacturers also sell bottles of solvent as "thinner", a few drops of which will return the correction fluid to its original liquid state. To avoid the inconveniences of organic solvents (safety and availability), some brands of fluid are water-based. However, those have
Protocol amending the Single Convention on Narcotic Drugs Protocol amending the Single Convention on Narcotic Drugs The 1972 Protocol amending the Single Convention on Narcotic Drugs was a protocol that made several changes to the Single Convention on Narcotic Drugs. It highlighted the need for treatment and rehabilitation of drug addicts, instructing parties to take "all practicable measures for the prevention of abuse of psychotropic substances and for the early identification, treatment, education, after-care, rehabilitation, and social reintegration of the persons involved". It also expanded the International Narcotics Control Board from 11 members to 13 members. In addition, the Protocol added Article 21 bis, "Limitation of Production of