Skin shortly after exposure to 35% Regulations vary, but low concentrations, such as 5%, are widely available and legal to buy for medical use. Most over-the-counter<unk>  solutions are not suitable for ingestion. Higher concentrations may be considered hazardous and typically are accompanied by a safety data sheet (SDS). In high concentrations,<unk>  is an aggressive oxidizer and will corrode many materials, including human skin. In the presence of a reducing agent, high concentrations of will react violently. High-concentration<unk>  streams, typically above 40%, should be considered hazardous due to concentrated<unk> 's meeting the definition of a DOT oxidizer according to U.S. regulations, if released into the environment. The EPA Reportable Quantity (RQ) for D001 hazardous wastes is , or approximately , of concentrated<unk> .<unk>  should be stored in a cool, dry, well-ventilated area and away from any flammable or combustible substances. It should be stored in a container composed of non-reactive materials such as stainless steel or glass (other materials including some plastics and aluminium alloys may also be suitable). Because it breaks down quickly when exposed to light, it should be stored in an opaque container, and pharmaceutical formulations typically come in brown bottles that block light.<unk> , either in pure or diluted form, may pose several risks, the main one being that it forms explosive mixtures upon contact with organic compounds. Distillation of<unk>  at normal pressures is highly dangerous. It is also corrosive, especially when concentrated, but even domestic-strength solutions may cause irritation to the eyes, mucous membranes, and skin. Swallowing<unk>  solutions is particularly dangerous, as decomposition in the stomach releases large quantities of gas (ten times the volume of a 3% solution), leading to internal bloating. Inhaling over 10% can cause severe pulmonary irritation. With a significant vapour pressure (1.2 kPa at 50 °C),<unk>  vapour is potentially hazardous. According to U.S. NIOSH, the immediately dangerous to life and health (IDLH) limit is only 75 ppm. The U.S. Occupational Safety and Health Administration (OSHA) has established a permissible exposure limit of 1.0 ppm calculated as an 8-hour time-weighted average (29 CFR 1910.1000, Table Z-1).<unk>  also has been classified by the American Conference of Governmental Industrial Hygienists (ACGIH) as a "known animal carcinogen, with unknown relevance on humans". For workplaces where there is a risk of exposure to the hazardous concentrations of the vapours, continuous monitors for<unk>  should be used. Information on the hazards of<unk>  is available from OSHA and from the ATSDR. Adverse effects on wounds Historically<unk>  was used for disinfecting wounds, partly because of its low cost and prompt availability compared to other antiseptics. Now it is thought to inhibit healing and to induce scarring, because it destroys newly formed skin cells. One study found that only very low concentrations (0.03% solution, this is a dilution of typical 3%<unk>  by 100 times) may induce healing, and only if not applied repeatedly. A 0.5% solution was found to impede healing. Surgical use can lead to gas embolism formation. Despite this, it is still used for wound treatment in many developing countries, and, in the United States, is prevalent as a major first aid antiseptic. Dermal exposure to dilute solutions of<unk>  causes whitening or bleaching of the skin due to microembolism caused by oxygen bubbles in the capillaries. Use in alternative medicine Practitioners of alternative medicine have advocated the use of<unk>  for various conditions, including emphysema, influenza, AIDS, and in particular cancer. There is no evidence of effectiveness and in some cases it has proved fatal. Both the effectiveness and safety of<unk>  therapy is scientifically questionable.<unk>  is produced by the immune system, but in a carefully controlled manner. Cells called phagocytes engulf pathogens and then use<unk>  to destroy them. The<unk>  is toxic to both the cell and the pathogen and so is kept within a special compartment, called a phagosome. Free<unk>  will damage any tissue it encounters via oxidative stress, a process that also has been proposed as a cause of cancer. Claims that<unk>  therapy increases cellular levels of oxygen have not been supported. The quantities administered would be expected to provide very little additional oxygen compared to that available from normal respiration. It is also difficult to raise the level of oxygen around cancer cells within a tumour, as the blood supply tends to be poor, a situation known as tumor hypoxia. Large oral doses of<unk>  at a 3% concentration may cause irritation and blistering to the mouth, throat, and abdomen as well as abdominal pain, vomiting, and diarrhea. Ingestion of<unk>  at concentrations of 35% or higher has been implicated as the cause of numerous gas embolism events resulting in hospitalisation. In these cases, hyperbaric oxygen therapy was used to treat the embolisms. Intravenous injection of<unk>  has been linked to several deaths. The American Cancer Society states that "there is no scientific evidence that<unk>  is a safe, effective, or useful cancer treatment." Furthermore, the therapy is not approved by the U.S. FDA. Historical incidents * On 16 July 1934, in Kummersdorf, Germany, a propellant tank containing an experimental monopropellant mixture consisting of<unk>  and ethanol exploded during a test, killing three people. * During the Second World War, doctors in German concentration camps experimented with the use of<unk>  injections in the killing of human subjects. * In April 1992, an explosion occurred at the<unk>  plant at Jarrie in France, due to technical failure of the computerised control system and resulting in one fatality and wide destruction of the plant. * Several people received minor injuries after a<unk>  spill on board a flight between the U.S. cities of Orlando and Memphis on 28 October 1998. * The Russian submarine K-141 Kursk sailed to perform an exercise of firing dummy torpedoes at the Pyotr Velikiy, a Kirov-class battlecruiser. On 12 August 2000, at 11:28 local time (07:28 UTC), there was an explosion while preparing to fire the torpedoes. The only credible report to date is that this was due to the failure and explosion of one of the Kursk's<unk> -fueled torpedoes. It is believed that HTP, a form of highly concentrated<unk>  used as propellant for the torpedo, seeped through its container, damaged either by rust or in the loading procedure back on land where an incident involving one of the torpedoes accidentally touching ground went unreported. The vessel was lost with all hands. A similar incident was responsible for the loss of HMS Sidon in 1955. * On 15 August 2010, a spill of about of cleaning fluid occurred on the 54th floor of 1515 Broadway, in Times Square, New York City. The spill, which a spokesperson for the New York City fire department said was of<unk> , shut down Broadway between West 42nd and West 48th streets as fire engines responded to the hazmat situation. There were no reported injuries.
Hydrogen peroxide
Carbon monoxide
Hydroxyl radical
Cyanide
Nitrosamine
Isothiocyanate
Nicosan
Hydrogen fluoride