in excess of 25 ppm, and conjunctivitis from concentrations below 10 ppm has been reported. In a study of five workers exposed for seven to 12 years to concentrations of 80 to 200 ppm at peaks, the principal findings were blackening and hyperkeratosis of the skin of the hands, conjunctivitis (but no corneal damage), bronchitis and pharyngitis, and erosion of the exposed teeth (incisors and canines). The hazards of solutions of acetic acid depend on the concentration. The following table lists the EU classification of acetic acid solutions: Concentrated acetic acid can be ignited only with difficulty at standard temperature and pressure, but becomes a flammable risk in temperatures greater than , and can form explosive mixtures with air at higher temperatures (explosive limits: 5.4–16%). See also Acetic acid (data page) Acids in wine Notes References External links National Pollutant Inventory – Acetic acid fact sheet NIOSH Pocket Guide to Chemical Hazards Method for sampling and analysis 29 CFR 1910.1000, Table Z-1 (US Permissible exposure limits) ChemSub Online: Acetic acid Calculation of vapor pressure, liquid density, dynamic liquid viscosity, surface tension of acetic acid Acetic acid bound to proteins in the PDB Swedish Chemicals Agency. Information sheet – Acetic Acid Process Flow sheet of Acetic acid Production by the Carbonylation of Methanol Acids in wine Antiseptics Commodity chemicals E-number additives Flavors Household chemicals Otologicals Photographic chemicals Solvents World Health Organization essential medicines Organic compounds with 2 carbon atoms