more resilient to the cold during World War II. Three fatalities were reported in dye factories, where DNP was used to make sulfur black dye. DNP was used extensively in diet pills from 1933 to 1938 after Cutting and Tainter at Stanford University made their first report on how the compound substantially increased metabolic rate. This effect occurs via DNP acting as a proton ionophore. After only its first year on the market, Tainter estimated that at least 100,000 people had been treated with DNP in the United States, in addition to many others abroad. In light of the adverse effects and fatal hyperthermia caused by DNP when it was used clinically, the dose was slowly titrated according to personal tolerance, which varies greatly. Concerns about dangerous side-effects and rapidly developing cataracts resulted in DNP being discontinued in the United States by the end of 1938. In 1938, the FDA included DNP in a list of drugs potentially so toxic that they should not be used even under a physician's supervision."In studies of intermediate-duration oral exposure to 2,4-DNP, cases of death from agranulocytosis (described in the discussion of Hematological Effects) have been attributed to 2,4-DNP. These cases occurred during the usual dosing regimens for weight loss, employing increasing doses in one case from 2.9 to 4.3 mg/kg/day of 2,4-DNP for 6 weeks (Dameshek and Gargill 1934); a dose of 1.03 mg/kg/day 2,4-DNP for 46 days in another case (Goldman and Haber 1936); and in another, from 0.62 to 3.8 mg/kg/day 2,4-DNP as sodium 2,4-DNP for 41 days (Silver 1934). In all cases, the patients were under medical supervision."Back in 1952 UK enacted new Agriculture (Poisonous Substances) Act to control very dangerous poisons, such as DNP and DNOC. Dinitrophenol was included in the Poisons Act 1972 poisons list order 1972. However DNP was dropped from the list in 1982. In 2021 December Home Office have launched a public consultation on potential amendments to the Poisons Act 1972. This consultation includes a proposal to add 2,4-Dinitrophenol (DNP) to the Poisons Act as a regulated poison. DNP, however, continues to be used by some bodybuilders and athletes to rapidly lose body fat. Fatal overdoses include cases of accidental exposure, suicide, and excessive intentional exposure (overdose). The substance's use as a dieting aid has also led to a number of accidental fatalities, including 33 confirmed DNP-related deaths in the UK since 2007. Annual Reports