immediately polymerized by the moisture in the membranes and become inert. These risks can be minimized by using cyanoacrylate in well-ventilated areas. About 5% of the population can become sensitized to cyanoacrylate fumes after repeated exposure, resulting in flu-like symptoms. Cyanoacrylate may also be a skin irritant, causing an allergic skin reaction. The American Conference of Governmental Industrial Hygienists (ACGIH) assign a threshold limit value exposure limit of 200 parts per billion. On rare occasions, inhalation may trigger asthma. There is no singular measurement of toxicity for all cyanoacrylate adhesives because of the large number of adhesives that contain various cyanoacrylate formulations. The United Kingdom's Health and Safety Executive and the United States National Toxicology Program have concluded that the use of ethyl cyanoacrylate is safe and that additional study is unnecessary. The compound 2-octyl cyanoacrylate degrades much more slowly due to its longer organic backbone (series of covalently bonded carbon molecules) and the adhesive does not reach the threshold of tissue toxicity. Due to the toxicity issues of ethyl cyanoacrylate, the use of 2-octyl cyanoacrylate for sutures is preferred. Reaction with cotton, wool, and other fibrous materials Applying cyanoacrylate to some natural materials such as cotton (jeans, cotton swabs, cotton balls, and certain yarns or fabrics), or leather or wool results in a powerful, rapid, exothermic reaction. This reaction also occurs with fiberglass and carbon fiber. The heat released may cause serious burns or release irritating white smoke. Material safety data sheets for cyanoacrylate instruct users not to wear cotton (jeans) or wool clothing, especially cotton gloves, when applying or handling cyanoacrylates. Solvents and debonders Acetone, commonly found as a fraction of nail polish remover (or at hardware stores in pure form), is a widely available solvent capable of softening cured cyanoacrylate. Other solvents include nitromethane, dimethylformamide, dimethyl sulfoxide, and methylene chloride. Another viable solvent for removing cured cyanoacrylate is gamma-butyrolactone. Commercial debonders are also available, many based on propylene carbonate. Shelf life Cyanoacrylate adhesives have a short shelf life. Date-stamped containers help to ensure that the adhesive is still viable. One manufacturer supplies the following information and advice: When kept unopened in a cool, dry location such as a refrigerator at a temperature of about 55 °F (13 °C), the shelf life of cyanoacrylate will be extended from about one year from manufacture to at least 15 months. If the adhesive is to be used within six months,