POSPHORIC ACID

POSPHORIC ACID
CASRN: 7664-38-2
http://toxnet.nlm.nih.gov/cgi-bin/sis/search/f?./temp/~AAAKiaGco:1

Human Health Effects:

Human Toxicity Excerpts:

A railroad accident in Somerville, Massachusetts led to a phosphorus trichloride liquid spillage. Attempted clean up with water led to the liberation of phosphorus trichloride, phosphorus acid, hydrogen chloride, and phosphorous oxides. Seventeen people exposed to this mixture were studied. Patients experienced eye irritation, lacrimation, nausea, vomiting, and dyspnea. Six patients had transient lactic dehydrogenase elevation. Although all patients had normal chest roentgenographic findings, pulmonary function tests showed statistically significant decreases in vital capacity (p= 0.02), maximal breathing capacity (p= 0.02), and forced expiratory volume vital capacity (p= 0.05) in those closest to the accident site. Patients exposed < 1.5 hr had significantly greater maximal expiratory flow rates at 25% of vital capacity when compared with patients who had been exposed longer (p= 0.02). In seven patients, repeated pulmonary function tests one month later showed improvement, suggesting that the acute effects may have been due to phosphorus acid toxicity. /Phosphorus trichloride/
[Wason S et al; Am J Med 77 (6): 1039-1042 (1984)]**PEER REVIEWED**

SYMPTOMATOLOGY (AFTER INGESTION OR SKIN CONTACT): 1) CORROSION OF MUCOUS MEMBRANES OF MOUTH, THROAT, AND ESOPHAGUS, WITH IMMEDIATE PAIN AND DYSPHAGIA. THE NECROTIC AREAS ARE AT FIRST GRAYISH WHITE BUT SOON ACQUIRE A BLACKISH DISCOLORATION AND SOMETIMES A SHRUNKEN OR WRINKLED TEXTURE; THE PROCESS IS DESCRIBED AS A "COAGULATION NECROSIS." 2) EPIGASTRIC PAIN, WHICH MAY BE ASSOCIATED WITH NAUSEA AND THE VOMITING OF MUCOID AND "COFFEE-GROUND" MATERIAL. AT TIMES, GASTRIC HEMORRHAGE MAY BE INTENSE, AND THE VOMITUS THEN CONTAINS FRESH BLOOD. PROFOUND THRIST. 3) ULCERATION OF ALL MEMBRANES AND TISSUES WITH WHICH THE ACID COMES IN CONTACT. ... 4) CIRCULATORY COLLAPSE WITH CLAMMY SKIN, WEAK AND RAPID PULSE, SHALLOW RESPIRATIONS, AND SCANTY URINE. CIRCULATORY SHOCK IS OFTEN THE IMMEDIATE CAUSE OF DEATH. 5) ASPHYXIAL DEATH DUE TO GLOTTIC EDEMA. 6) LATE ESOPHAGEAL, GASTRIC AND PYLORIC STRICTURES AND STENOSES, WHICH MAY REQUIRE MAJOR SURGICAL REPAIR, SHOULD BE ANTICIPATED. SIGNS OF OBSTRUCTION COMMONLY APPEAR WITHIN A FEW WEEKS BUT MAY BE DELAYED FOR MONTHS AND EVEN YEARS. PERMANENT SCARS MAY ALSO APPEAR IN THE CORNEA, SKIN AND OROPHARYNX. 7) UNCORRECTED CIRCULATORY COLLAPSE OF SEVERAL HOURS' DURATION MAY LEAD TO RENAL FAILURE AND ISCHEMIC LESIONS IN THE LIVER AND HEART. /ACIDS/
[Gosselin, R.E., R.P. Smith, H.C. Hodge. Clinical Toxicology of Commercial Products. 5th ed. Baltimore: Williams and Wilkins, 1984.,p. II-102]**PEER REVIEWED**

Phosphoric acid is not irritating to the eyes or respiratory tract, unless it is introduced into the atmosphere as a spray or mist, because phosphoric acid has a low vapor pressure at room temperature.
[Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) PublicationNo. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981. 2]**PEER REVIEWED**

Symptoms: Conjunctivitis, burns, irritant to trachea, nausea and vomiting by swallowing, stomachache, diarrhea, acid intoxication, shock.
[ITII. Toxic and Hazardous Industrial Chemicals Safety Manual. Tokyo, Japan: The International Technical Information Institute, 1988. 414]**PEER REVIEWED**

Phosphoric acid (orthophosphoric acid, metaphosphoric acid) topically may irritate and injure the eyes, owing to its acidity, but systemically phosphate has no poisonous action on the eye. Tested on human eyes, 0.16 M orthophosphoric acid buffered to pH 2.5 caused moderate brief stinging sensation but no injury when applied as a single drop. A drop of the same solution adjusted to pH 3.4 caused no discomfort.
[Grant, W.M. Toxicology of the Eye. 3rd ed. Springfield, IL: Charles C. Thomas Publisher, 1986. 733]**PEER REVIEWED**

Human Toxicity Values:

TCLo inhalation human 100 mg/cu m
[Sax, N.I. Dangerous Properties of Industrial Materials. 6th ed. New York, NY: Van Nostrand Reinhold, 1984. 2213]**PEER REVIEWED**

Skin, Eye and Respiratory Irritations:

Causes severe eye and skin irritation.
[Fire Protection Guide to Hazardous Materials. 12 ed. Quincy, MA: National Fire Protection Association, 1997.,p. 49-104]**PEER REVIEWED**

Phosphoric acid mist is an irritant to the eyes, upper respiratory tract, and skin. The solid is especially irritating to the skin in the presence of moisture ... A dilute solution buffered to pH 2.5 caused a moderate, brief stinging sensation but no injury when dropped in the human eye. A 75% solution will cause severe skin burns.
[Zenz, C., O.B. Dickerson, E.P. Horvath. Occupational Medicine. 3rd ed. St. Louis, MO., 1994 690]**PEER REVIEWED**

Drug Warnings:

ACID CLEANING: ACIDS SUCH AS SULFURIC ... PHOSPHORIC, SOMETIMES WITH CHROMIC OR HYDROFLUORIC, ARE USED IN WATER SOLUTIONS & THEIR SPLASH HAZARD & CORROSIVE ACTION ON SKIN, CLOTHING, & MACHINERY ARE WELL RECOGNIZED. BUBBLES OF HYDROGEN RISING FROM BATH CARRY INVISIBLE ACID MIST. ...
[Patty, F. (ed.). Industrial Hygiene and Toxicology: Volume II: Toxicology. 2nd ed. New York: Interscience Publishers, 1963. 2280]**PEER REVIEWED**

Splash contact of concentrated strong acids, such as ... phosphoric/acid/, ... can prove as, severely and devastatingly injurious to the eye as splashes of strong alkalies.
[Grant, W.M. Toxicology of the Eye. 3rd ed. Springfield, IL: Charles C. Thomas Publisher, 1986. 46]**PEER REVIEWED**

Medical Surveillance:

Initial medical examination: Employees should be screened for history of certain medical conditions (chronic respiratory disease, skin disease) which might place the employee at increased risk from phosphoric acid exposure. Periodic medical examination: Any employee developing impaired pulmonary function or dermatitis should be referred for further medical examination.
[Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) PublicationNo. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981. 1]**PEER REVIEWED**

Populations at Special Risk:

Chronic pulmonary disease: In persons with impaired pulmonary function, especially those with obstructive airway diseases, the breathing of phosphoric acid dust or mist might cause exacerbation of symptoms due to its irritant properties. Skin disease: Phosphoric acid dust, mist, or solutions may cause dermatitis. Persons with pre-existing skin disorders may be more susceptible to the effects of this agent.
[Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) PublicationNo. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981. 1]**PEER REVIEWED**

Probable Routes of Human Exposure:

Inhalation of mist, ingestion, eye, and skin contact. /Occupational exposure/
[Sittig, M. Handbook of Toxic And Hazardous Chemicals. Park Ridge, NJ: Noyes Data Corporation, 1981. 543]**PEER REVIEWED**

Antidote and Emergency Treatment:

Irrigate eyes with water; wash contaminated part of body with soap and water; gastric lavage (stomach wash) taking care not to perforate the gastrointestinal tract, if swallowed.
[ITII. Toxic and Hazardous Industrial Chemicals Safety Manual. Tokyo, Japan: The International Technical Information Institute, 1988. 414]**PEER REVIEWED**

Basic treatment: Establish a patent airway. Suction if necessary. Watch for signs of respiratory insufficiency and assist respirations if needed. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... . Monitor for shock and treat if necessary ... . For eye contamination, flush the eyes immediately with water. Irrigate each eye continuously with normal saline during transport ... . Do not use emetics. Activated charcoal is not effective. For ingestion, rinse mouth and administer 5 mL/kg up to 200 mL of water for dilution if the patent can swallow, has a strong gag reflex, and does not drool ... . Do not attempt to neutralize because of exothermic reaction. Cover skin burns with dry, sterile dressings after decontamination ... . /Inorganic Acids and Related compounds/
[Bronstein, A.C., P.L. Currance; Emergency Care for Hazardous Materials Exposure. 2nd ed. St. Louis, MO. Mosby Lifeline. 1994. 149]**PEER REVIEWED**

Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in respiratory arrest. Early intubation, at the first sign of upper airway obstruction, may be necessary. Positive-pressure ventilation techniques with a bag-valve-mask device may be beneficial. Monitor cardiac rhythm and treat arrhythmias as necessary ... . Start an IV of D5W TKO /SRP: "To keep open", minimal flow rate/. Use lactated Ringer's if signs of hypovolemia are present. Watch for signs of fluid overload. Consider drug therapy for pulmonary edema ... . For hypotension with signs of hypovolemia, administer fluid cautiously. Consider vasopressors if patient is hypotensive with a normal fluid volume. Watch for signs of fluid overload ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Inorganic Acids and Related compounds/
[Bronstein, A.C., P.L. Currance; Emergency Care for Hazardous Materials Exposure. 2nd ed. St. Louis, MO. Mosby Lifeline. 1994. 149]**PEER REVIEWED**

Animal Toxicity Studies:

Non-Human Toxicity Excerpts:

IRRIGATION OF RABBIT'S EYE FOR FIVE MIN WITH ORTHOPHOSPHORIC ACID DILUTED TO PH 3.8 CAUSED SLIGHT TRANSIENT EPITHELIAL EDEMA & CONJUNCTIVAL HYPEREMIA BUT EYE WAS COMPLETELY NORMAL BY NEXT DAY.
[Grant, W.M. Toxicology of the Eye. 3rd ed. Springfield, IL: Charles C. Thomas Publisher, 1986. 733]**PEER REVIEWED**

Plant foliage (peas, beans, beets, rape, and weeds) were destroyed by spraying with 15-20% phosphoric acid.
[Environment Canada; Tech Info for Problem Spills: Phosphoric Acid (Draft) p.61 (1982)]**PEER REVIEWED**

The concentration of hydrogen ions which caused 50% mortality of bluegill in 96 hr was between pH 3.5 and 3.0 for sulfuric acid, nitric acid, phosphoric acid and hydrochloric acid. Therefore, it appears that any contribution by the anions of these acids to fish toxicity is similar. Thus, the quantity rather than the quality of acids is the primary factor in fish toxicity brought about by acid precipitaiton. At sublethal concentration of acids, bluegill became hypoactive with respect to their swimming behavior.
[Ellgaard EG, Gilmore JY Jr; J Fish Biol 25 (2): 133-7 (1984)]**PEER REVIEWED**

Non-Human Toxicity Values:

LD50 Rat oral 1530 mg/kg
[ITII. Toxic and Hazardous Industrial Chemicals Safety Manual. Tokyo, Japan: The International Technical Information Institute, 1988. 414]**PEER REVIEWED**

LD50 Rabbit skin 2740 mg/kg
[ITII. Toxic and Hazardous Industrial Chemicals Safety Manual. Tokyo, Japan: The International Technical Information Institute, 1988. 414]**PEER REVIEWED**

Ecotoxicity Values:

TLm mosquito fish 138 mg/l/24-96 hr in turbid water at 22-24 deg C. /Conditions of bioassay not specified/
[Environment Canada; Tech Info for Problem Spills: Phosphoric Acid (Draft) p.61 (1981)]**PEER REVIEWED**

Metabolism/Pharmacokinetics:

Absorption, Distribution & Excretion:

The hygroscopic growth of phosphoric acid aerosol (diameter change > 0.5 micrometers) within the human tracheobronchial tree is modeled to investigate changes in deposition characteristics when compared to nonhygroscopic aerosols of identical preinspired size. Phosphoric acid particles are assumed to grow in a stepwise fashion to 99% relative humidity within conducting airways of the lung, having initially reached equilibrium at 90% relative humidity (T= 37 degrees) in the trachea. Deposition efficiencies for growth and no growth are calculated from theoretical equations for inertial impaction, sedimentation, and diffusion. The results show that neglecting the growth of an inhaled phosphoric acid aerosol may result in underestimation of the total deliverable dose by a factor of as much as 600-700%. Significant differences in regional deposition sites for hygroscopic or nonhygroscopic aerosols are predicted. Increased deposition efficiencies imply that measured physical properties (respirable fraction, aerodynamic diameter) of aerosols alone are not sufficient to assess deposition characteristics within the lung; hygroscopic growth must also be considered.
[Martonen TB, Clark ML; Fundam Appl Toxicol 3 (1): 10-5 (1983)]**PEER REVIEWED**

/Ortho/ phosphate is absorbed from, and to a limited extent secreted into, the gastrointestinal tract. Transport of phosphate from the gut lumen is an active, energy-dependent process that is modified by several factors. ... Vitamin D stimulates phosphate absorption, an effect reported to precede its action on calcium ion transport. In adults, about two thirds of the ingested phosphate is absorbed, and that which is absorbed is almost entirely excreted into the urine. In growing children, phosphate balance is positive. Concentrations of phosphate in plasma are higher in children than in adults. This "hyperphosphatemia" decreases the affinity of hemoglobin for oxygen and is hypothesized to explain the physiological "anemia" of childhood. /Phosphates/
[Hardman, J.G., L.E. Limbird, P.B. Molinoff, R.W. Ruddon, A.G. Goodman (eds.). Goodman and Gilman's The Pharmacological Basis of Therapeutics. 9th ed. New York, NY: McGraw-Hill, 1996. 1524]**PEER REVIEWED**

Pharmacology:

Therapeutic Uses:

DILUTED PHOSPHORIC ACID NATIONAL FORMULARY: IT HAS ... BEEN EMPLOYED IN LEAD POISONING AND IN OTHER CONDITIONS IN WHICH IT IS DESIRED TO ADMINISTER LARGE AMT OF PHOSPHATE AND @ SAME TIME PRODUCE MILD ACIDOSIS. IT HAS BEEN GIVEN IN DOSE OF 60 ML DAILY (5 ML/HR) UNDER CAREFULLY CONTROLLED CONDITIONS.
[Osol, A. (ed.). Remington's Pharmaceutical Sciences. 16th ed. Easton, Pennsylvania: Mack Publishing Co., 1980. 1263]**PEER REVIEWED**

Phosphoric acid is used ... to control the pH of the urinary tract in many animals, particularly in mink and cats, to prevent stone formation.
[Kirk-Othmer Encyclopedia of Chemical Technology. 3rd ed., Volumes 1-26. New York, NY: John Wiley and Sons, 1978-1984.,p. 17:108]**PEER REVIEWED**

Pharmaceutic aid (solvent).
[Budavari, S. (ed.). The Merck Index - Encyclopedia of Chemicals, Drugs and Biologicals. Rahway, NJ: Merck and Co., Inc., 1989. 1167]**PEER REVIEWED**

MEDICATION (VET): HAS BEEN USED TO TREAT LEAD POISONING.
[Budavari, S. (ed.). The Merck Index - Encyclopedia of Chemicals, Drugs and Biologicals. Rahway, NJ: Merck and Co., Inc., 1989. 1167]**PEER REVIEWED**

Drug Warnings:

ACID CLEANING: ACIDS SUCH AS SULFURIC ... PHOSPHORIC, SOMETIMES WITH CHROMIC OR HYDROFLUORIC, ARE USED IN WATER SOLUTIONS & THEIR SPLASH HAZARD & CORROSIVE ACTION ON SKIN, CLOTHING, & MACHINERY ARE WELL RECOGNIZED. BUBBLES OF HYDROGEN RISING FROM BATH CARRY INVISIBLE ACID MIST. ...
[Patty, F. (ed.). Industrial Hygiene and Toxicology: Volume II: Toxicology. 2nd ed. New York: Interscience Publishers, 1963. 2280]**PEER REVIEWED**

Splash contact of concentrated strong acids, such as ... phosphoric/acid/, ... can prove as, severely and devastatingly injurious to the eye as splashes of strong alkalies.
[Grant, W.M. Toxicology of the Eye. 3rd ed. Springfield, IL: Charles C. Thomas Publisher, 1986. 46]**PEER REVIEWED**

Bionecessity:

Inorganic nutrient requirements for Candida utilis grown on ethanol: 2-4 g of phosphorus is the nutrient input per 100 g of cells produced. Orthophosphoric acid is the typical source.
[Kirk-Othmer Encyclopedia of Chemical Technology. 3rd ed., Volumes 1-26. New York, NY: John Wiley and Sons, 1978-1984.,p. 24:796]**PEER REVIEWED**

Environmental Fate & Exposure:

Probable Routes of Human Exposure:

Inhalation of mist, ingestion, eye, and skin contact. /Occupational exposure/
[Sittig, M. Handbook of Toxic And Hazardous Chemicals. Park Ridge, NJ: Noyes Data Corporation, 1981. 543]**PEER REVIEWED**

Natural Pollution Sources:

... PHOSPHORIC ACID, IS A NATURAL CONSTITUENT OF MANY FRUITS AND THEIR JUICES.
[Furia, T.E. (ed.). CRC Handbook of Food Additives. 2nd ed. Cleveland: The Chemical Rubber Co., 1972. 619]**PEER REVIEWED**

Environmental Fate:

Aquatic Fate: While acidity may be reduced readily by natural water hardness minerals, the phosphate may persist indefinitely.
[Environment Canada; Tech Info for Problem Spills: Phosphoric Acid (Draft) p.61 (1981)]**PEER REVIEWED**

Soil Adsorption/Mobility:

When spilled onto soil, phosphoric acid will infiltrate downward, the rate being greater with lower concentration because of reduced viscosity. ... During transport through the soil, phosphoric acid will dissolve some of the soil material, in particular, carbonate-based materials. The acid will be neutralized to some degree with adsorption of the proton and phosphate ions also possible. However, significant amounts of acid will remain for transport down toward the groundwater table. Upon reaching the groundwater table, the acid will continue to move in the direction of groundwater flow. A contaminated plume will be produced with dilution and dispersion serving to reduce the acid concentration.
[Environment Canada; Tech Info for Problem Spills: Phosphoric Acid (Draft) p.51 (1981)]**PEER REVIEWED**

Environmental Standards & Regulations:

FIFRA Requirements:

Residues of phosphoric acid are exempted from the requirement of a tolerance when used as a buffer in accordance with good agricultural practices as inert (or occasionally active) ingredients in pesticide formulations applied to growing crops or to raw agricultural commodities after harvest.
[40 CFR 180.1001(c) (7/1/97)]**PEER REVIEWED**

As the federal pesticide law FIFRA directs, EPA is conducting a comprehensive review of older pesticides to consider their health and environmental effects and make decisions about their future use. Under this pesticide reregistration program, EPA examines health and safety data for pesticide active ingredients initially registered before November 1, 1984, and determines whether they are eligible for reregistration. In addition, all pesticides must meet the new safety standard of the Food Quality Protection Act of 1996. Pesticides for which EPA had not issued Registration Standards prior to the effective date of FIFRA, as amended in 1988, were divided into three lists based upon their potential for human exposure and other factors, with List B containing pesticides of greater concern and List D pesticides of less concern. Phosphoric acid is found on List D. Case No: 4064; Pesticide type: fungicide, herbicide, and antimicrobial; Case Status: RED Approved 02/94; OPP has made a decision that some/all uses of the pesticide are eligible for reregistration, as reflected in a Reregistration Eligibility Decision (RED) document .; Active ingredient (AI): Phosphoric acid; AI Status: OPP has completed a Reregistration Eligibility Decision (RED) document for the case/AI.
[USEPA/OPP; Status of Pesticides in Registration, Reregistration and Special Review p.325 (Spring, 1998) EPA 738-R-98-002]**QC REVIEWED**

Acceptable Daily Intakes:

FAO/WHO EXPERT COMMITTEE ON FOOD ADDITIVES...RECOMMENDED.../LEVELS/ FOR TOTAL DIETARY PHOSPHORUS...UNCONDITIONAL ACCEPTANCE LEVEL /OF LESS THAN 30 MG/KG BODY WT/ IS CONSIDERED SAFE IN ANY TYPE OF DIET...CONDITIONAL ACCEPTANCE LEVEL /OF 30-70 MG/KG BODY WT/ IS ACCEPTABLE ONLY WHEN DIETARY CALCIUM LEVEL IS HIGH /PHOSPHATES/
[Furia, T.E. (ed.). CRC Handbook of Food Additives. 2nd ed. Cleveland: The Chemical Rubber Co., 1972. 641]**PEER REVIEWED**

CERCLA Reportable Quantities:

Persons in charge of vessels or facilities are required to notify the National Response Center (NRC) immediately, when there is a release of this designated hazardous substance, in an amount equal to or greater than its reportable quantity of 5000 lb or 2270 kg. The toll free number of the NRC is (800) 424-8802; In the Washington D.C. metropolitan area (202) 426-2675. The rule for determining when notification is required is stated in 40 CFR 302.4 (section IV. D.3.b).
[40 CFR 302.4 (7/1/97)]**PEER REVIEWED**

FDA Requirements:

Phosphoric acid used as a multiple purpose GRAS food substance in food for human consumption is generally recognized as safe when used in accordance with good manufacturing practice.
[21 CFR 182.1073 (4/1/97]**PEER REVIEWED**

Phosphoric acid used as a general purpose food additive in animal drugs, feeds, and related products is generally recognized as safe when used in accordance with good manufacturing or feeding practice.
[21 CFR 582.1073 (4/1/97]**PEER REVIEWED**

Allowable Tolerances:

Residues of phosphoric acid are exempted from the requirement of a tolerance when used as a buffer in accordance with good agricultural practices as inert (or occasionally active) ingredients in pesticide formulations applied to growing crops or to raw agricultural commodities after harvest.
[40 CFR 180.1001(c) (7/1/97)]**PEER REVIEWED**

Chemical/Physical Properties:

Molecular Formula:

H3-O4-P
**PEER REVIEWED**

Molecular Weight:

98.00
[Budavari, S. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Whitehouse Station, NJ: Merck and Co., Inc., 1996. 1264]**PEER REVIEWED**

Color/Form:

Unstable orthorhombic crystals or clear syrupy liquid
[Budavari, S. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Whitehouse Station, NJ: Merck and Co., Inc., 1996. 1264]**PEER REVIEWED**

Colorless, sparkling liquid or transparent, crystalline solid, depending on concentration and temperature. At 20 deg C the 50% and 75% strengths are mobile liquids, the 85% is of syrupy consistency; the 100% acid is in the form of crystals.
[Lewis, R.J., Sr (Ed.). Hawley's Condensed Chemical Dictionary. 12th ed. New York, NY: Van Nostrand Rheinhold Co., 1993 906]**PEER REVIEWED**

Odor:

Odorless
[Lewis, R.J., Sr (Ed.). Hawley's Condensed Chemical Dictionary. 12th ed. New York, NY: Van Nostrand Rheinhold Co., 1993 908]**PEER REVIEWED**

Taste:

Pleasing acid taste when suitably diluted
[Budavari, S. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Whitehouse Station, NJ: Merck and Co., Inc., 1996. 1264]**PEER REVIEWED**

Boiling Point:

At 213 deg C losing 1/2 water
[Lide, D.R. (ed). CRC Handbook of Chemistry and Physics. 72nd ed. Boca Raton, FL: CRC Press, 1991-1992.,p. 4-81]**PEER REVIEWED**

Melting Point:

42.35 deg C
[Budavari, S. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Whitehouse Station, NJ: Merck and Co., Inc., 1996. 1264]**PEER REVIEWED**

Corrosivity:

Corrosive to ferrous metals & alloys
[Lewis, R.J., Sr (Ed.). Hawley's Condensed Chemical Dictionary. 12th ed. New York, NY: Van Nostrand Rheinhold Co., 1993 908]**PEER REVIEWED**

Density/Specific Gravity:

1.834 at 18 deg C
[Budavari, S. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Whitehouse Station, NJ: Merck and Co., Inc., 1996. 1264]**PEER REVIEWED**

Dissociation Constants:

Tribasic acid: pK1: 2.15; pK2: 7.09; pK3: 12.32
[Budavari, S. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Whitehouse Station, NJ: Merck and Co., Inc., 1996. 1264]**PEER REVIEWED**

pH:

1.5 (0.1 N aq soln)
[Budavari, S. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Whitehouse Station, NJ: Merck and Co., Inc., 1996. 1264]**PEER REVIEWED**

Solubilities:

Sol in alcohol; sol in 8 vol of 3:1 ether:alcohol mixt
[Budavari, S. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Whitehouse Station, NJ: Merck and Co., Inc., 1996. 1264]**PEER REVIEWED**

VERY SOL IN HOT WATER; 548 G SOL IN 100 CC COLD WATER
[Lide, D.R. (ed). CRC Handbook of Chemistry and Physics. 72nd ed. Boca Raton, FL: CRC Press, 1991-1992.,p. 4-81]**PEER REVIEWED**

Spectral Properties:

Index of refraction: 1.34203 @ 17.5 deg C/D, 10% soln; 1.35032 @ 17.5 deg C/D, 20% soln; 1.35846 @ 17.5 deg C/D, 30% soln
[Budavari, S. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Whitehouse Station, NJ: Merck and Co., Inc., 1996. 1264]**PEER REVIEWED**

Vapor Density:

3.4 (air= 1 at the boiling point of phosphoric acid)
[Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) PublicationNo. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981. 2]**PEER REVIEWED**

Vapor Pressure:

0.0285 torr @ 20 DEG C
[American Conference of Governmental Industrial Hygienists, Inc. Documentation of the Threshold Limit Values and Biological Exposure Indices. 6th ed. Volumes I,II, III. Cincinnati, OH: ACGIH, 1991. 1250]**PEER REVIEWED**

Viscosity:

3.86 mPa.s (40% solution at 20 deg C).
[Environment Canada; Tech Info for Problem Spills: Phosphoric Acid (Draft) p.4 (1982)]**PEER REVIEWED**

Other Chemical/Physical Properties:

PH: 2.0-2.2 /DETERMINED IN 1% SOLN AND IN 10-50% SLURRIES OF INSOL COMPOUNDS/
[Furia, T.E. (ed.). CRC Handbook of Food Additives. 2nd ed. Cleveland: The Chemical Rubber Co., 1972. 620]**PEER REVIEWED**

IT FORMS 3 SERIES OF SALTS: PRIMARY PHOSPHATES; DIBASIC PHOSPHATES; AND TRIBASIC PHOSPHATES.
[Osol, A. (ed.). Remington's Pharmaceutical Sciences. 16th ed. Easton, Pennsylvania: Mack Publishing Co., 1980. 1263]**PEER REVIEWED**

Easily supercooled into a glass; Heat of formation (crystalline): -306.2 Kcal/mol; Heat of soln: +2.79 Kcal/mol.
[Budavari, S. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Whitehouse Station, NJ: Merck and Co., Inc., 1996. 1264]**PEER REVIEWED**

Acid containing about 88% orthophosphoric acid will frequently crystallize on prolonged cooling, forms hemihydrate; becomes anhyd @ 150 deg C, gradually changes to pyrophosphoric acid @ about 200 deg C; above 300 deg C, metaphosphoric acid; hot concn acid attacks porcelain & granite ware.
[Budavari, S. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Whitehouse Station, NJ: Merck and Co., Inc., 1996. 1264]**PEER REVIEWED**

DELIQUESCENT
[Weast, R.C. (ed.). Handbook of Chemistry and Physics. 64th ed. Boca Raton, Florida: CRC Press Inc., 1983-84.,p. B-119]**PEER REVIEWED**

Melting point: 75% -17.5 deg C; 80% 4.6 deg C; 85% 21 deg C.
[Environment Canada; Tech Info for Problem Spills: Phosphoric Acid (Draft) p.1 (1982)]**PEER REVIEWED**

Density at 25 deg C: 75% 1.574; 80% 1.628; 85% 1.685.
[Environment Canada; Tech Info for Problem Spills: Phosphoric Acid (Draft) p.1 (1982)]**PEER REVIEWED**

Hygroscopic; Latent heat of fusion = 10.5 kJ/mol at the melting point; Heat capacity at constant pressure = 106.2 J/mole (25 deg C).
[Environment Canada; Tech Info for Problem Spills: Phosphoric Acid (Draft) p.4 (1982)]**PEER REVIEWED**

/Bulk density =/ 15.6 lb/gal. /Phosphoric acid, liquid or solution/
[Association of American Railroads. Emergency Handling of Hazardous Materials in Surface Transportation. Washington, D.C.: Assoc. of American Railroads,Hazardous Materials Systems (BOE), 1987. 548]**PEER REVIEWED**

Phosphoric acid is a chelating agent.
[Kirk-Othmer Encyclopedia of Chemical Technology. 3rd ed., Volumes 1-26. New York, NY: John Wiley and Sons, 1978-1984.,p. V3 104 (1978)]**PEER REVIEWED**

Density @ 25 deg C: 1.8741 (100% soln); 1.6850 (85% soln); 1.3334 (50% soln); 1.0523 (10% soln) /Phosphoric acid solutions/
[Budavari, S. (ed.). The Merck Index - Encyclopedia of Chemicals, Drugs and Biologicals. Rahway, NJ: Merck and Co., Inc., 1989. 1166]**PEER REVIEWED**

Chemical Safety & Handling:

DOT Emergency Guidelines:

Health: TOXIC, inhalation, ingestion, or skin contact with material may cause severe injury or death. Contact with molten substance may cause severe burns to skin and eyes. Avoid any skin contact. Effects of contact or inhalation may be delayed. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may be corrosive and/or toxic and cause pollution. /Phosphoric acid/
[U.S. Department of Transportation. 1996 North American Emergency Response Guidebook. A Guidebook for First Responders During the Initial Phase of aHazardous Materials/Dangerous Goods Incident. U.S. Department of Transportation (U.S. DOT) Research and Special Programs Administration, Office of HazardousMaterials Initiatives and Training (DHM-50), Washington, D.C. (1996).,p. G-154]**PEER REVIEWED**

Fire or explosion: Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. Some are oxidizers and may ignite combustibles (wood, paper, oil, clothing, etc.). Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated. /Phosphoric acid/
[U.S. Department of Transportation. 1996 North American Emergency Response Guidebook. A Guidebook for First Responders During the Initial Phase of aHazardous Materials/Dangerous Goods Incident. U.S. Department of Transportation (U.S. DOT) Research and Special Programs Administration, Office of HazardousMaterials Initiatives and Training (DHM-50), Washington, D.C. (1996).,p. G-154]**PEER REVIEWED**

Public safety: ... Isolate spill or leak area immediately for at least 25 to 50 meters (80 to 160 feet) in all directions. Keep unauthorized personnel away. Stay upwind. Keep out of low areas. Ventilate enclosed areas. /Phosphoric acid/
[U.S. Department of Transportation. 1996 North American Emergency Response Guidebook. A Guidebook for First Responders During the Initial Phase of aHazardous Materials/Dangerous Goods Incident. U.S. Department of Transportation (U.S. DOT) Research and Special Programs Administration, Office of HazardousMaterials Initiatives and Training (DHM-50), Washington, D.C. (1996).,p. G-154]**PEER REVIEWED**

Protective clothing: Wear positive pressure self-contained breathing apparatus (SCBA). Wear chemical protective clothing which is specifically recommended by the manufacturer. Structural firefighters' protective clothing is recommended for fire situations ONLY, it is not effective in spill situations. /Phosphoric acid/
[U.S. Department of Transportation. 1996 North American Emergency Response Guidebook. A Guidebook for First Responders During the Initial Phase of aHazardous Materials/Dangerous Goods Incident. U.S. Department of Transportation (U.S. DOT) Research and Special Programs Administration, Office of HazardousMaterials Initiatives and Training (DHM-50), Washington, D.C. (1996).,p. G-154]**PEER REVIEWED**

Evacuation: Spill: Fire: If tank, rail car or tank truck is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. /Phosphoric acid/
[U.S. Department of Transportation. 1996 North American Emergency Response Guidebook. A Guidebook for First Responders During the Initial Phase of aHazardous Materials/Dangerous Goods Incident. U.S. Department of Transportation (U.S. DOT) Research and Special Programs Administration, Office of HazardousMaterials Initiatives and Training (DHM-50), Washington, D.C. (1996).,p. G-154]**PEER REVIEWED**

Fire: Small fires: Dry chemical, CO2 or water spray. Large fires: Dry chemical, CO2, alcohol-resistant foam or water spray. Move containers from fire area if you can do it without risk. Dike fire control water for later disposal; do not scatter the material. Fire involving tanks or car/trailer loads: Fight fire from maximum distance or use unmanned hose holders or monitor nozzles. Do not get water inside containers. Cool containers with flooding quantities of water until well after fire is out. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from the ends of tanks. /Phosphoric acid/
[U.S. Department of Transportation. 1996 North American Emergency Response Guidebook. A Guidebook for First Responders During the Initial Phase of aHazardous Materials/Dangerous Goods Incident. U.S. Department of Transportation (U.S. DOT) Research and Special Programs Administration, Office of HazardousMaterials Initiatives and Training (DHM-50), Washington, D.C. (1996).,p. G-154]**PEER REVIEWED**

Spill or leak: ELIMINATE all ignition sources (no smoking, flares, sparks or flames in immediate area). Do not touch damaged containers or spilled material unless wearing appropriate protective clothing. Stop leak if you can do it without risk. Prevent entry into waterways, sewers, basements or confined areas. Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers. DO NOT GET WATER INSIDE CONTAINERS. /Phosphoric acid/
[U.S. Department of Transportation. 1996 North American Emergency Response Guidebook. A Guidebook for First Responders During the Initial Phase of aHazardous Materials/Dangerous Goods Incident. U.S. Department of Transportation (U.S. DOT) Research and Special Programs Administration, Office of HazardousMaterials Initiatives and Training (DHM-50), Washington, D.C. (1996).,p. G-154]**PEER REVIEWED**

First aid: Move victim to fresh air. Call emergency medical care. Apply artificial respiration if victim is not breathing. Do not use mouth-to-mouth method if victim ingested or inhaled the substance; induce artificial respiration with the aid of a pocket mask equipped with a one-way valve or other proper respiratory medical device. Administer oxygen if breathing is difficult. Remove and isolate contaminated clothing and shoes. In case of contact with substance, immediately flush skin or eyes with running water for at least 20 minutes. For minor skin contact, avoid spreading material on unaffected skin. Keep victim warm and quiet. Effects of exposure (inhalation, ingestion or skin contact) to substance may be delayed. Ensure that medical personnel are aware of the material(s) involved, and take precautions to protect themselves. /Phosphoric acid/
[U.S. Department of Transportation. 1996 North American Emergency Response Guidebook. A Guidebook for First Responders During the Initial Phase of aHazardous Materials/Dangerous Goods Incident. U.S. Department of Transportation (U.S. DOT) Research and Special Programs Administration, Office of HazardousMaterials Initiatives and Training (DHM-50), Washington, D.C. (1996).,p. G-154]**PEER REVIEWED**

Skin, Eye and Respiratory Irritations:

Causes severe eye and skin irritation.
[Fire Protection Guide to Hazardous Materials. 12 ed. Quincy, MA: National Fire Protection Association, 1997.,p. 49-104]**PEER REVIEWED**

Phosphoric acid mist is an irritant to the eyes, upper respiratory tract, and skin. The solid is especially irritating to the skin in the presence of moisture ... A dilute solution buffered to pH 2.5 caused a moderate, brief stinging sensation but no injury when dropped in the human eye. A 75% solution will cause severe skin burns.
[Zenz, C., O.B. Dickerson, E.P. Horvath. Occupational Medicine. 3rd ed. St. Louis, MO., 1994 690]**PEER REVIEWED**

Fire Potential:

NOT COMBUSTIBLE.
[Fire Protection Guide to Hazardous Materials. 12 ed. Quincy, MA: National Fire Protection Association, 1997.,p. 49-104]**PEER REVIEWED**

NFPA Hazard Classification:

Health: 3. 3= Materials that, on short exposure, could cause serious temporary or residual injury, including those requiring protection from all bodily contact. Fire fighters may enter the area only if they are protected from all contact with the material. Full protective clothing, including self-contained breathing apparatus, coat, pants, gloves, boots and bands around legs, arms, and waist, should be provided. No skin surface should be exposed.
[Fire Protection Guide to Hazardous Materials. 12 ed. Quincy, MA: National Fire Protection Association, 1997.,p. 49-104]**PEER REVIEWED**

Flammability: 0. 0= This degree includes any material that will not burn.
[Fire Protection Guide to Hazardous Materials. 12 ed. Quincy, MA: National Fire Protection Association, 1997.,p. 49-104]**PEER REVIEWED**

Reactivity: 0. 0= This degree includes materials that are normally stable, even under fire exposure conditions, and that do not react with water. Normal fire fighting procedures may be used.
[Fire Protection Guide to Hazardous Materials. 12 ed. Quincy, MA: National Fire Protection Association, 1997.,p. 49-104]**PEER REVIEWED**

Fire Fighting Procedures:

Use water spray to keep fire-exposed containers cool. Extinguish fire using agent suitable for surrounding fire.
[Fire Protection Guide to Hazardous Materials. 12 ed. Quincy, MA: National Fire Protection Association, 1997.,p. 49-104]**PEER REVIEWED**

If material /is/ on fire or involved in /a/ fire, extinguish fire using agent suitable for type of surrounding fire. (Material itself does not burn or burns with difficulty.) Use water in flooding quantities as fog. Cool all containers with flooding quantities of water. Apply water from as far a distance as possible.
[Association of American Railroads. Emergency Handling of Hazardous Materials in Surface Transportation. Washington, D.C.: Assoc. of American Railroads,Hazardous Materials Systems (BOE), 1987. 548]**PEER REVIEWED**

Toxic Combustion Products:

... Combustion by-products include oxides of phosphorus.
[Fire Protection Guide to Hazardous Materials. 12 ed. Quincy, MA: National Fire Protection Association, 1997.,p. 49-104]**PEER REVIEWED**

Firefighting Hazards:

Flammable /hydrogen/ gas is formed on contact with metals.
[U.S. Coast Guard, Department of Transportation. CHRIS - Hazardous Chemical Data. Volume II. Washington, D.C.: U.S. Government Printing Office, 1984-5.]**PEER REVIEWED**

Hazardous Reactivities & Incompatibilities:

Reacts with metals to liberate flammable hydrogen gas.
[U.S. Coast Guard, Department of Transportation. CHRIS - Hazardous Chemical Data. Volume II. Washington, D.C.: U.S. Government Printing Office, 1984-5.]**PEER REVIEWED**

With sodium tetrahydroborate: Interaction of sodium and other tetrahydroborates with anhydrous acids (phosphoric acid) to generate diborane is very exothermic, and may be dangerously violent with rapid mixing.
[Bretherick, L. Handbook of Reactive Chemical Hazards. 4th ed. Boston, MA: Butterworth-Heinemann Ltd., 1990 64]**PEER REVIEWED**

Heat generated with: Alcohols and glycols; Aldehydes; Amides; Amines; Azo-compounds; Carbamates; Caustics; Esters; Ketones; Phenols and cresols; Organophosphates; Epoxides; Combustible materials; Explosives; Unsaturated halides; And organic peroxides.
[Environment Canada; Tech Info for Problem Spills: Phosphoric Acid (Draft) p.70 (1981)]**PEER REVIEWED**

Formation of flammable gases with: Aldehydes; Cyanides; Mercaptans; and sulfides. Formation of toxic fumes with: Cyanides; Fluorides; Halogenated organics; Sulfides; And organic peroxides.
[Environment Canada; Tech Info for Problem Spills: Phosphoric Acid (Draft) p.70 (1981)]**PEER REVIEWED**

With chlorides and stainless steel: Presence of traces of chloride ion in technical 75% phosphoric acid in a closed stainless storage tank caused corrosive liberation of hydrogen which later exploded at a sparking contact.
[Bretherick, L. Handbook of Reactive Chemical Hazards. 4th ed. Boston, MA: Butterworth-Heinemann Ltd., 1990 1236]**PEER REVIEWED**

Hot, dilute phosphoric acid reacts with nickel carbonate to form trinickel orthophosphate.
[Kirk-Othmer Encyclopedia of Chemical Technology. 3rd ed., Volumes 1-26. New York, NY: John Wiley and Sons, 1978-1984.,p. V15:P806]**PEER REVIEWED**

Reacts with strong alkalies and most metals.
[Fire Protection Guide to Hazardous Materials. 12 ed. Quincy, MA: National Fire Protection Association, 1997.,p. 49-104]**PEER REVIEWED**

Strong caustics, most metals [Note: Readily reacts with metals to form flammable hydrogen gas. DO NOT MIX WITH SOLUTIONS CONTAINING BLEACH OR AMMONIA].
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 254]**PEER REVIEWED**

Mixtures with nitromethane are explosive. Reacts with chlorides + stainless steel to form explosive hydrogen gas.
[Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 9th ed. Volumes 1-3. New York, NY: Van Nostrand Reinhold, 1996. 2687]**PEER REVIEWED**

Hazardous Decomposition:

Oxides of phosphorus are formed during thermal decomposition.
[National Fire Protection Guide. Fire Protection Guide on Hazardous Materials. 10 th ed. Quincy, MA: National Fire Protection Association, 1991.,p. 49-137]**PEER REVIEWED**

Decomposition products: converted to pyrophosphoric acid (H4P2O7) when heated to 213 deg C.
[American Conference of Governmental Industrial Hygienists, Inc. Documentation of the Threshold Limit Values and Biological Exposure Indices. 6th ed. Volumes I,II, III. Cincinnati, OH: ACGIH, 1991. 1250]**PEER REVIEWED**

Hazardous Polymerization:

Violent polymerization with: Azo compounds; Epoxides; And polymerizable compounds.
[Environment Canada; Tech Info for Problem Spills: Phosphoric Acid (Draft) p.70 (1981)]**PEER REVIEWED**

Other Hazardous Reaction:

Evolves hydrogen on contact with most metals.
[Fire Protection Guide to Hazardous Materials. 12 ed. Quincy, MA: National Fire Protection Association, 1997.,p. 49-104]**PEER REVIEWED**

Prior History of Accidents:

In a train derailment near an urban area, one of the five derailed tank cars was ruptured and spilled approximately 114,000 liters of phosphoric acid. Response personnel arrived at the spill site and contained the spilled product. The collected acid was then removed to a local landfill site, where it was dumped in a pit lined with lime. More lime was added until the mixture solidified. The mixture was subsequently spread over a nearby field as fertilizer.
[Environment Canada; Tech Info for Problem Spills: Phosphoric Acid (Draft) p.80 (1981)]**PEER REVIEWED**

Immediately Dangerous to Life or Health:

1000 mg/cu m
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 254]**PEER REVIEWED**

Protective Equipment & Clothing:

Goggles or face shield
[U.S. Coast Guard, Department of Transportation. CHRIS - Hazardous Chemical Data. Volume II. Washington, D.C.: U.S. Government Printing Office, 1984-5.]**PEER REVIEWED**

Wear rubber gloves, and overalls prepared with a total seal.
[ITII. Toxic and Hazardous Industrial Chemicals Safety Manual. Tokyo, Japan: The International Technical Information Institute, 1988. 414]**PEER REVIEWED**

Wear special protective clothing and positive pressure self-contained breathing apparatus.
[Fire Protection Guide to Hazardous Materials. 12 ed. Quincy, MA: National Fire Protection Association, 1997.,p. 49-104]**PEER REVIEWED**

Respiratory protection (supplied-air respirator with full facepiece or self-contained breathing apparatus) should be available where these compounds are manufactured or used and should be worn in case of emergency and overexposure. /Phosphorus compounds/
[International Labour Office. Encyclopedia of Occupational Health and Safety. Vols. I&II. Geneva, Switzerland: International Labour Office, 1983. 1684]**PEER REVIEWED**

Wear appropriate personal protective clothing to prevent skin contact.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 255]**PEER REVIEWED**

Wear appropriate eye protection to prevent eye contact.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 255]**PEER REVIEWED**

Eyewash fountains should be provided in areas where there is any possibility that workers could be exposed to liquids containing > 1.6% of contaminant; this is irrespective of the recommendation involving the wearing of eye protection.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 255]**QC REVIEWED**

Facilities for quickly drenching the body should be provided within the immediate work area for emergency use where there is a possibility of exposure with liquids containing > 1.6% of contaminant. [Note: It is intended that these facilities provide a sufficient quantity or flow of water to quickly remove the substance from any body areas likely to be exposed. The actual determination of what constitutes an adequate quick drench facility depends on the specific circumstances. In certain instances, a deluge shower should be readily available, whereas in others, the availability of water from a sink or hose could be considered adequate.]
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 255]**QC REVIEWED**

Recommendations for respirator selection. Max concn for use: 25 mg/cu m. Respirator Class(es): Any supplied-air respirator operated in a continuous flow mode. May require eye protection.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 255]**PEER REVIEWED**

Recommendations for respirator selection. Max concn for use: 50 mg/cu m. Respirator Class(es): Any air-purifying, full-facepiece respirator with a high-efficiency particulate filter. Any self-contained breathing apparatus with a full facepiece. Any supplied-air respirator with a full facepiece.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 255]**PEER REVIEWED**

Recommendations for respirator selection. Max concn for use: 1000 mg/cu m. Respirator Class(es): Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 255]**PEER REVIEWED**

Recommendations for respirator selection. Condition: Emergency or planned entry into unknown concn or IDLH conditions: Respirator Class(es): Any self-contained breathing apparatus that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode. Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode in combination with an auxiliary self-contained breathing apparatus operated in pressure-demand or other positive-pressure mode.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 255]**PEER REVIEWED**

Recommendations for respirator selection. Condition: Escape from suddenly occurring respiratory hazards: Respirator Class(es): Any air-purifying, full-facepiece respirator with a high-efficiency particulate filter. Any appropriate escape-type, self-contained breathing apparatus.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 255]**PEER REVIEWED**

Preventive Measures:

Contact lenses should not be worn when working with this chemical.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 255]**QC REVIEWED**

VENTILATION CONTROL: ACID CLEANING: NATURE & EXTENT OF VENTILATION CONTROL REQUIRED DEPENDS ON RATE OF ACID MIST ESCAPE; WHERE EXPOSURE ... MILD ... ADDN OF INHIBITOR MAY MAKE PROCESS OR SLOT VENTILATION UNNECESSARY. INHIBITORS SHOULD NEVER BE ADDED TO AUTOMATICALLY TIMED CONVEYORIZED JOB WITHOUT ADJUSTMENT ... .
[Patty, F. (ed.). Industrial Hygiene and Toxicology: Volume II: Toxicology. 2nd ed. New York: Interscience Publishers, 1963. 2280]**PEER REVIEWED**

PHOSPHORIC ACID SOLN IN WATER IS USED ALONE OR WITH A MIXTURE OF ALCOHOLS AND ETHERS, INCLUDING BUTYL CELLOSOLVE, TO REMOVE LIGHT RUST ON STEEL ... IF MISTS, FOGS, OR ELEVATED TEMPERATURES ARE INVOLVED, VENTILATION CONTROL IS NECESSARY.
[Patty, F. (ed.). Industrial Hygiene and Toxicology: Volume II: Toxicology. 2nd ed. New York: Interscience Publishers, 1963. 2281]**PEER REVIEWED**

IN PRESENCE OF IMPURITIES IN METALS, NASCENT HYDROGEN MAY BE GENERATED WHICH COULD LEAD TO FORMATION OF PHOSPHINE GAS. IT IS NECESSARY TO AVOID INHALATION OF VAPORS COMING FROM PHOSPHORIC ACID METAL CLEANING TANKS. SLOTTED LOCAL EXHAUST VENTILATION @ UPPER EDGES OF ... TANKS ... RECOMMENDED.
[International Labour Office. Encyclopedia of Occupational Health and Safety. Vols. I&II. Geneva, Switzerland: International Labour Office, 1983. 1683]**PEER REVIEWED**

Clothing contaminated with phosphoric acid should be placed in closed containers for storage until it can be discarded or until provision is made for the removal of phosphoric acid from the clothing. If the clothing is to be laundered or otherwise cleaned to remove the phosphoric acid, the person performing the operation should be informed of phosphoric acid's hazardous properties.
[Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) PublicationNo. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981. 2]**PEER REVIEWED**

Non-impervious clothing which becomes contaminated with phosphoric acid should be removed immediately and not reworn until the phosphoric acid is removed from the clothing.
[Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) PublicationNo. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981. 2]**PEER REVIEWED**

Avoid breathing vapors. Keep upwind. Avoid bodily contact with the material. Do not handle broken packages without protective equipment. Wash away any material which may have contacted the body with copious amounts of water or soap and water.
[Association of American Railroads. Emergency Handling of Hazardous Materials in Surface Transportation. Washington, D.C.: Assoc. of American Railroads,Hazardous Materials Systems (BOE), 1987. 548]**PEER REVIEWED**

The worker should immediately wash the skin when it becomes contaminated.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 255]**PEER REVIEWED**

Work clothing that becomes wet or significantly contaminated should be removed and replaced.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 255]**PEER REVIEWED**

Workers whose clothing may have become contaminated should change into uncontaminated clothing before leaving the work premises.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 255]**PEER REVIEWED**

SRP: The scientific literature for the use of contact lenses in industry is conflicting. The benefit or detrimental effects of wearing contact lenses depend not only upon the substance, but also on factors including the form of the substance, characteristics and duration of the exposure, the uses of other eye protection equipment, and the hygiene of the lenses. However, there may be individual substances whose irritating or corrosive properties are such that the wearing of contact lenses would be harmful to the eye. In those specific cases, contact lenses should not be worn. In any event, the usual eye protection equipment should be worn even when contact lenses are in place.
**PEER REVIEWED**

SRP: Contaminated protective clothing should be segregated in such a manner so that there is no direct personal contact by personnel who handle, dispose, or clean the clothing. Quality assurance to ascertain the completeness of the cleaning procedures should be implemented before the decontaminated protective clothing is returned for reuse by the workers. Contaminated clothing should not be taken home at end of shift, but should remain at employee's place of work for cleaning.
**PEER REVIEWED**

Shipment Methods and Regulations:

No person may /transport,/ offer or accept a hazardous material for transportation in commerce unless that person is registered in conformance ... and the hazardous material is properly classed, described, packaged, marked, labeled, and in condition for shipment as required or authorized by ... /the hazardous materials regulations (49 CFR 171-177)./
[49 CFR 171.2 (7/1/96)]**PEER REVIEWED**

The International Air Transport Association (IATA) Dangerous Goods Regulations are published by the IATA Dangerous Goods Board pursuant to IATA Resolutions 618 and 619 and constitute a manual of industry carrier regulations to be followed by all IATA Member airlines when transporting hazardous materials.
[IATA. Dangerous Goods Regulations. 38th ed. Montreal, Canada and Geneva, Switzerland: International Air Transport Association, Dangerous Goods Board, January, 1997. 198]**PEER REVIEWED**

The International Maritime Dangerous Goods Code lays down basic principles for transporting hazardous chemicals. Detailed recommendations for individual substances and a number of recommendations for good practice are included in the classes dealing with such substances. A general index of technical names has also been compiled. This index should always be consulted when attempting to locate the appropriate procedures to be used when shipping any substance or article.
[IMDG; International Maritime Dangerous Goods Code; International Maritime Organization p.8194 (1988)]**PEER REVIEWED**

Storage Conditions:

STORE IN COOL, DRY, WELL-VENTILATED LOCATION. SEPARATE FROM ALKALIES AND MOST METALS.
[Fire Protection Guide to Hazardous Materials. 12 ed. Quincy, MA: National Fire Protection Association, 1997.,p. 49-104]**PEER REVIEWED**

The hot concentrated acid attacks porcelain and granite ware. Phosphoric acid may be stored in suitable stainless steel containers.
[Budavari, S. (ed.). The Merck Index - Encyclopedia of Chemicals, Drugs and Biologicals. Rahway, NJ: Merck and Co., Inc., 1989. 1166]**PEER REVIEWED**

Cleanup Methods:

1. Ventilate area of spill or leak. 2. If in the solid form, collect spilled material in the most convenient and safe manner for reclamation or for disposal in a secured sanitary landfill. 3. If in the liquid form, collect for reclamation or absorb in vermiculite, dry sand, earth, or a similar material.
[Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) PublicationNo. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981.]**PEER REVIEWED**

Cellosized absorbent material may be used for vapor suppression and containment of spills.
[Environment Canada; Tech Info for Problem Spills: Phosphoric Acid (Draft) p.75 (1981)]**PEER REVIEWED**

Air spill: Apply water spray or mist to knock down vapors. Vapor knockdown water is corrosive or toxic and should be diked for containment.
[Association of American Railroads. Emergency Handling of Hazardous Materials in Surface Transportation. Washington, D.C.: Assoc. of American Railroads,Hazardous Materials Systems (BOE), 1987. 548]**PEER REVIEWED**

Water spill: Neutralize with agricultural lime (slaked lime), crushed limestone, or sodium bicarbonate. Adjust pH to neutral (pH-7). Use mechanical dredges or lifts to remove immobilized masses of pollutants and precipitates.
[Association of American Railroads. Emergency Handling of Hazardous Materials in Surface Transportation. Washington, D.C.: Assoc. of American Railroads,Hazardous Materials Systems (BOE), 1987. 548]**PEER REVIEWED**

Land spill: Dig a pit, pond, lagoon, holding area to contain liquid or solid material. /SRP: If time permits, pits, ponds, lagoons, soak holes, or holding areas should be sealed with an impermeable flexible membrane liner./ Dike surface flow using soil, sand bags, foamed polyurethane, or foamed concrete. Absorb bulk liquid with fly ash or cement powder. Neutralize with agricultural lime, crushed limestone, or sodium bicarbonate.
[Association of American Railroads. Emergency Handling of Hazardous Materials in Surface Transportation. Washington, D.C.: Assoc. of American Railroads,Hazardous Materials Systems (BOE), 1987. 548]**PEER REVIEWED**

Disposal Methods:

SRP: At the time of review, criteria for land treatment or burial (sanitary landfill) disposal practices are subject to significant revision. Prior to implementing land disposal of waste residue (including waste sludge), consult with environmental regulatory agencies for guidance on acceptable disposal practices.
**PEER REVIEWED**

Following cleanup, separate solids then precipitate with lime pH 11.0. ... An anionic polymer may be added to assist in settling of the solids. ... If necessary, the water, after treatment with lime, can pass through dual media filtration to remove the solids and then neutralize with hydrochloric acid. ... Following neutralization either at the spill site or at a waste management facility, the resultant sludge can be disposed of in a secure landfill.
[Environment Canada; Tech Info for Problem Spills: Phosphoric Acid (Draft) p.75 (1981)]**PEER REVIEWED**

Technology appropriate for incineration: Rotary kiln.
[USEPA; Engineering Handbook for Hazardous Waste Incineration p.2-57 (1981) EPA 68-03-3025]**PEER REVIEWED**

Technology appropriate for incineration: Venturi scrubber.
[USEPA; Engineering Handbook for Hazardous Waste Incineration p.2-58 (1981) EPA 68-03-3025]**PEER REVIEWED**

Neutralization & landfill: Neutralize with soda ash or soda ash-slaked lime mixture (1:1) and bury in an approved landfill.
[United Nations. Treatment and Disposal Methods for Waste Chemicals (IRPTC File). Data Profile Series No. 5. Geneva, Switzerland: United Nations Environmental Programme, Dec. 1985. 234]**PEER REVIEWED**

Occupational Exposure Standards:

OSHA Standards:

Permissible Exposure Limit: Table Z-1 8-hr Time Weighted Avg: 1 mg/cu m.
[29 CFR 1910.1000 (7/1/98)]**PEER REVIEWED**

Vacated 1989 OSHA PEL TWA 1 mg/cu m; STEL 3 mg/cu m is still enforced in some states.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 370]**PEER REVIEWED**

Threshold Limit Values:

8 hr Time Weighted Avg (TWA) 1 mg/cu m; 15 min Short Term Exposure Limit (STEL) 3 mg/cu m
[American Conference of Governmental Industrial Hygienists. Threshold Limit Values (TLVs) for Chemical Substances and Physical Agents Biological Exposure Indices for 1998. Cincinnati, OH: ACGIH, 1998. 57]**QC REVIEWED**

NIOSH Recommendations:

Recommended Exposure Limit: 10 Hr Time-Weighted avg: 1 mg/cu m.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 254]**QC REVIEWED**

Recommended Exposure Limit: 15 Min Short-Term Exposure Limit: 3 mg/cu m.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 254]**QC REVIEWED**

Immediately Dangerous to Life or Health:

1000 mg/cu m
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 254]**PEER REVIEWED**

Other Occupational Permissible Levels:

Australia: 1 mg/cu m, STEL 3 mg/cu m (1990); Sweden: 1 mg/cu m (mist), short-term value 3 mg/cu m, 15 min (1990); United Kingdom: 1 mg/cu m, 10 min STEL 3 mg/cu m (1991)
[American Conference of Governmental Industrial Hygienists, Inc. Documentation of the Threshold Limit Values and Biological Exposure Indices. 6th ed. Volumes I,II, III. Cincinnati, OH: ACGIH, 1991. 1250]**PEER REVIEWED**

Manufacturing/Use Information:

Major Uses:

Polymer gasoline catalyst; etchant (semiconductor manufacture); acidulant (soft drinks; prepared foods); aluminum brightening/anodizing agent; aluminum/steel/magnesium/zinc anticorrosion treatment reagent; microbial fermentation nutrient; refractories raw material.
[Ashford, R.D. Ashford's Dictionary of Industrial Chemicals. London, England: Wavelength Publications Ltd., 1994. 694]**PEER REVIEWED**

In the manufacture of superphosphates for fertilizers, other phosphate salts, polyphosphates, detergents. Acid catalyst in making ethylene, purifying hydrogen peroxide. As acidulant and flavor, synergistic antioxidant and sequestrant in food. Pharmaceutic aid (solvent). In dental cements; process engraving; rustproofing of metals before painting; coagulating rubber latex; as analytical reagent.
[Budavari, S. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Whitehouse Station, NJ: Merck and Co., Inc., 1996. 1264]**PEER REVIEWED**

In gelatin mfr; in lakes in cotton dyeing; soil stabilizer; waxes & polishes; binder for ceramics; activated carbon.
[Lewis, R.J., Sr (Ed.). Hawley's Condensed Chemical Dictionary. 12th ed. New York, NY: Van Nostrand Rheinhold Co., 1993 908]**PEER REVIEWED**

MEDICATION (VET)
[Budavari, S. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Whitehouse Station, NJ: Merck and Co., Inc., 1996. 1264]**PEER REVIEWED**

Manufacture of concentrated superphosphates, various ammonium phosphates, and solid and liquid mixed fertilizers. In direct application as a fertilizer in the West to calcareous soils. /50% to 80% solutions/
[Farm Chemicals Handbook 1998. Willoughby, OH: Meister Publishing Co., 1998.,p. B34]**PEER REVIEWED**

The greatest consumption of phosphoric acid is in the manufacture of phosphate salts, as opposed to the direct use of the acid.
[Kirk-Othmer Encyclopedia of Chemical Technology. 4th ed. Volumes 1: New York, NY. John Wiley and Sons, 1991-Present.,p. V18 673]**PEER REVIEWED**

AS A WEAK ACID IN VARIOUS PHARMACEUTICAL PREPARATIONS.
[Osol, A. (ed.). Remington's Pharmaceutical Sciences. 16th ed. Easton, Pennsylvania: Mack Publishing Co., 1980. 1263]**PEER REVIEWED**

Over 90% of the phosphoric acid produced in the United States and worldwide is wet-process phosphoric acid used almost exclusively for agricultural applications as both fertilizers and animal feed supplements.
[Kirk-Othmer Encyclopedia of Chemical Technology. 4th ed. Volumes 1: New York, NY. John Wiley and Sons, 1991-Present.,p. V18 678]**PEER REVIEWED**

Although constituting a small proportion of the total wet-acid production, a significant amount of phosphoric acid for food and technical applications is made by purifying wet-process acid.
[Kirk-Othmer Encyclopedia of Chemical Technology. 4th ed. Volumes 1: New York, NY. John Wiley and Sons, 1991-Present.,p. V18 678]**PEER REVIEWED**

Manufacturers:

Agrium US Inc., Hq, 4582 South Ulster Street, Suite 1400, Denver CO 80237, (303) 804-4400. Production site: Soda Springs, ID 83276
[SRI. 1997 Directory of Chemical Producers - United States of America. Menlo Park, CA: SRI International 1997. 807]**PEER REVIEWED**

Farmland Hydro, L.P., State Road 640, Bartow, FL 33831, (813) 533-1141
[SRI. 1997 Directory of Chemical Producers - United States of America. Menlo Park, CA: SRI International 1997. 807]**PEER REVIEWED**

IMC-Agrico Company, Hq, Old Highway 37, P.O. Box 2000-1100, Mulbery, FL 33860, (941) 428-2500. Production sites: Donaldson, LA 70346; Mulberry, FL 33860; Nichols, FL 33863; South Pierce, FL 33830; Uncle Sam, LA 70792
[SRI. 1997 Directory of Chemical Producers - United States of America. Menlo Park, CA: SRI International 1997. 808]**PEER REVIEWED**

SF Phosphates Limited Company, 515 So. Highway 430, P.O. Box 1789, Rock Springs, WY 82901, (307) 382-1400
[SRI. 1997 Directory of Chemical Producers - United States of America. Menlo Park, CA: SRI International 1997. 808]**PEER REVIEWED**

U.S. Agri-Chemicals Corporation, Hq, 3225 State Road 630 West, Fort Meade, FL 33841, (941) 285-8121. Production site: Fort Meade, FL 33841
[SRI. 1997 Directory of Chemical Producers - United States of America. Menlo Park, CA: SRI International 1997. 808]**PEER REVIEWED**

Mobil Corp, Hq, Mobil Oil Corporation, 3225 Gallows Rd, Fairfax, VA 22037-0001; (703) 846-3000; Mobil Mining & Minerals Company, PO Box 26683, Richmond, VA 23261; Production site: Pasadena, TX 77501
[SRI. 1997 Directory of Chemical Producers - United States of America. Menlo Park, CA: SRI International 1997. 808]**PEER REVIEWED**

PCS Nitrogen Fertilizer, L.P., 6750 Poplar Avenue. Suite 600, Memphis, TN 38138-7419, (901) 758-5200. Production site: Geismar, LA70734
[SRI. 1997 Directory of Chemical Producers - United States of America. Menlo Park, CA: SRI International 1997. 808]**PEER REVIEWED**

PCS Phosphates Co., Inc., Hq, P.O. Box 30321, Raleigh, NC 27622, (919) 881-2700. Production sites: Auroro, NC 27806; White Springs, FL 32096
[SRI. 1997 Directory of Chemical Producers - United States of America. Menlo Park, CA: SRI International 1997. 808]**PEER REVIEWED**

Albright & Wilson Americas, 4851 Lake Brook Drive, Glen Allen, VA 23060 (804)968-6300. Production site: Charleston, SC 29405
[SRI. 1997 Directory of Chemical Producers - United States of America. Menlo Park, CA: SRI International 1997. 808]**PEER REVIEWED**

Cargill Fertilizer, Inc., 8813 Hwy. 41 South, Riverview, FL 33569 (813) 671-6146. Production sites: Bartow, FL 33830; Riverview FL 33569
[SRI. 1997 Directory of Chemical Producers - United States of America. Menlo Park, CA: SRI International 1997. 808]**PEER REVIEWED**

CF Industries Inc., Hq, 1 Salem Lake Drive, Long Grove, IL 60047, (708) 438-9500. Production site: Bartow FL 33830; Plant City, FL 33566
[SRI. 1997 Directory of Chemical Producers - United States of America. Menlo Park, CA: SRI International 1997. 808]**PEER REVIEWED**

Mulberry Phosphates, Inc., P.O. Drawer 797, Mulberry, FL 33860, (941) 425-1176
[SRI. 1997 Directory of Chemical Producers - United States of America. Menlo Park, CA: SRI International 1997. 808]**PEER REVIEWED**

Piney Point Phosphates, Inc., Hq, 13300 U.S. Highway 41 North, Palmetto, FL 34221, (941) 722-4555. Production site: Piney Point, FL 34221
[SRI. 1997 Directory of Chemical Producers - United States of America. Menlo Park, CA: SRI International 1997. 808]**PEER REVIEWED**

J R Simplot Co, Hq, PO Box 912, Pocatello, ID 83204, (208) 238-2700; Minerals and Chemical Division, (same address); Production site: Pocatello, ID 83204
[SRI. 1997 Directory of Chemical Producers - United States of America. Menlo Park, CA: SRI International 1997. 808]**PEER REVIEWED**

U.S. Agri-Chemicals Corporation, Hq, 3225 State Road 630 West, Fort Meade, FL 33841, (941) 285-8121. Production site: Bartow, FL
[SRI. 1997 Directory of Chemical Producers - United States of America. Menlo Park, CA: SRI International 1997. 808]**PEER REVIEWED**

Mississippi Phosphates Corp., P.O. Box 848, Pascagoula, MS 39568, (601) 762-3210
[SRI. 1997 Directory of Chemical Producers - United States of America. Menlo Park, CA: SRI International 1997. 808]**PEER REVIEWED**

Rhone-Poulenc Inc., Chemical Sector, Hq, CN 5266, Princeton, NJ 08543- 5266, (908) 297-1597. Production sites: Geismar, LA 70734; Morrisville, PA 19067; Nashville, TN 37202
[SRI. 1997 Directory of Chemical Producers - United States of America. Menlo Park, CA: SRI International 1997. 808]**PEER REVIEWED**

FMC Corporation, Chemical Products Group, Alkali Chemicals Division, Phosporus Chemicals Division, Hq, 200 East Randolph Drive, Chicago, IL 60601 (312) 861-6000. Production sites: Carteret, NJ 07008; Green River, WY 82935 Lawrence, KS 66044
[SRI. 1997 Directory of Chemical Producers - United States of America. Menlo Park, CA: SRI International 1997. 808]**PEER REVIEWED**

Monsanto Company, Chemical Group, Hq, 800 North Lindbergh Boulevard, St. Louis, MO 63167, (314) 694-1000. Production sites: Carondelet, MO 63111; Augusta, GA 30903; Trenton, MI 48183
[SRI. 1997 Directory of Chemical Producers - United States of America. Menlo Park, CA: SRI International 1997. 808]**PEER REVIEWED**

Purified Acid Partners, 4851 Lake Brook Dr., Glen Allen, VA 23060, (804) 968-6385. Production site: Aurora, NC 27806
[SRI. 1997 Directory of Chemical Producers - United States of America. Menlo Park, CA: SRI International 1997. 808]**PEER REVIEWED**

Methods of Manufacturing:

TWO NEW PROCESSES FOR THE PRODUCTION OF PHOSPHORIC ACID HAVE BEEN DEVELOPED; THE BESA-2 PROCESS, DEVELOPED BY BOHNA ENGINEERING & RESEARCH, SAN FRANCISCO, AND OCCIDENTAL RESEARCH CORP'S KPA PROCESS. IN THE BESA-2 PROCESS, PHOSPHATE ROCK AND SULFURIC ACID REACT IN TWO STEPS. THE FIRST IS THE CONVENTIONAL MEANS OF PRODUCING SINGLE SUPER-PHOSPHATE, GYPSUM, AND MONOCALCIUM PHOSPHATE. IN THE SECOND STEP, THERE IS DIGESTION OF THE SINGLE SUPERPHOSPHATE IN METHANOL WITH SULFURIC ACID. THE SECOND NEW METHOD, THE KPA PROCESS, REDUCES PHOSPHATE ORE TO PHOSPHORUS IN A HIGH-TEMPERATURE ROTARY KILN. IT UTILIZES THE HEATS OF COMBUSTION OF PHOSPHORUS AND CARBON MONOXIDE IN THE KILN TO PROVIDE MOST OF THE ENERGY REQUIRED FOR REDUCTION AND REPLACES THE ELECTRIC POWER USED IN THE FURNACE PROCESS WITH FOSSIL FUEL AS THE ENERGY SOURCE.
[HAGGIN J; CHEM ENG NEWS 63 (42): 23-7 (1985)]**PEER REVIEWED**

Wet-process acid is manufactured by the digestion of phosphate rock (calcium phosphate) with sulfuric acid. Other acids such as hydrochloric acid may be used, but the sulfuric acid-based processes are by far the most prevalent. Phosphoric acid is separated from the resultant calcium sulfate slurry by filtration.
[Kirk-Othmer Encyclopedia of Chemical Technology. 4th ed. Volumes 1: New York, NY. John Wiley and Sons, 1991-Present.,p. V18 678]**PEER REVIEWED**

Thermal (furnace) process: White (yellow) phosphorus is burned in excess air and the resulting phosphorus pentoxide is hydrated, heats of combustion and hydration are removed, and the phosphoric acid mist collected.
[Kirk-Othmer Encyclopedia of Chemical Technology. 4th ed. Volumes 1: New York, NY. John Wiley and Sons, 1991-Present.,p. V18 678]**PEER REVIEWED**

General Manufacturing Information:

... CAN INACTIVATE METALLIC IONS, WHICH ARE CAPABLE OF INTERFERING WITH NECESSARY FOOD-PROCESSING REACTIONS ... /INACTIVATION IS/ EITHER BY PPTN & REMOVING THEM FROM INTERFERENCE WITH DESIRED FOOD-PROCESSING REACTIONS OR BY COMPLEXING & MAINTAINING THEM IN SOL, BOUND STATE. /PHOSPHATES/
[Furia, T.E. (ed.). CRC Handbook of Food Additives. 2nd ed. Cleveland: The Chemical Rubber Co., 1972. 644]**PEER REVIEWED**

IT HAS BEEN FOUND TO BE EXCELLENT ACIDIFYING AGENT IN FOOD APPLICATIONS. IT IS AVAILABLE COMMERCIALLY AS VISCOUS, COLORLESS, SYRUPY LIQ, AND IT IS USUALLY SOLD ACCORDING TO ITS PHOSPHORIC ANHYDRIDE CONTENT.
[Furia, T.E. (ed.). CRC Handbook of Food Additives. 2nd ed. Cleveland: The Chemical Rubber Co., 1972. 619]**PEER REVIEWED**

A COMMERCIAL GRADE OF ACID IS MADE BY ACTION OF SULFURIC ACID ON BONE ASH OR CALCIUM PHOSPHATE MINERALS. THE CRUDE ACID SO OBTAINED IS UNFIT FOR MEDICINAL USE UNLESS IT IS PURIFIED. ... AS A WEAK ACID IN VARIOUS PHARMACEUTICAL PREPARATIONS.
[Osol, A. (ed.). Remington's Pharmaceutical Sciences. 16th ed. Easton, Pennsylvania: Mack Publishing Co., 1980. 1263]**PEER REVIEWED**

Phosphoric acid is the most economical acidulant for carbonated beverages available.
[Kirk-Othmer Encyclopedia of Chemical Technology. 4th ed. Volumes 1: New York, NY. John Wiley and Sons, 1991-Present.,p. V5 24]**PEER REVIEWED**

Reagent grade concentrated phosphoric acid is 85-87% (wt/wt) phosphoric acid (equivalent to about 17 M). It appears to be as corrosive as sulfuric and hydrochloric acids.
[Gosselin, R.E., R.P. Smith, H.C. Hodge. Clinical Toxicology of Commercial Products. 5th ed. Baltimore: Williams and Wilkins, 1984.,p. II-101]**PEER REVIEWED**

Wet-process phosphoric acid (53-54% P2O5), commonly referred to as merchant grade, is the type most widely used as an intermediate in the production of phosphate fertilizers.
[Farm Chemicals Handbook 1998. Willoughby, OH: Meister Publishing Co., 1998.,p. B34]**PEER REVIEWED**

Pure solid H3PO4 contains 72.44% P2O5. The maximum concentration of the liquid phosphoric acid is 88% H3PO4 or 63.75% P2O5.
[Farm Chemicals Handbook 1998. Willoughby, OH: Meister Publishing Co., 1998.,p. B34]**PEER REVIEWED**

Second largest volume mineral acid produced, after sulfuric acid.
[Kirk-Othmer Encyclopedia of Chemical Technology. 4th ed. Volumes 1: New York, NY. John Wiley and Sons, 1991-Present.,p. V18 673]**PEER REVIEWED**

Thermal acid, manufactured from elemental phosphorus, is more expensive and considerably purer than wet-process acid, which is produced directly from phosphatic ores.
[Kirk-Othmer Encyclopedia of Chemical Technology. 4th ed. Volumes 1: New York, NY. John Wiley and Sons, 1991-Present.,p. V18 673]**PEER REVIEWED**

Industrial-grades (technical, food, pharmaceutical, etc.) of phosphoric acid are made by the thermal route or by purification of wet-process acid.
[Kirk-Othmer Encyclopedia of Chemical Technology. 4th ed. Volumes 1: New York, NY. John Wiley and Sons, 1991-Present.,p. V18 715]**PEER REVIEWED**

Because of environmental concerns and related legislation, there has been a shift in production of industrial-grade acid since the 1970's towards wet-acid purification and only the most economically viable elemental phosphorus and thermal acid producers remain in business.
[Kirk-Othmer Encyclopedia of Chemical Technology. 4th ed. Volumes 1: New York, NY. John Wiley and Sons, 1991-Present.,p. V18 715]**PEER REVIEWED**

About 84% of phosphate rock production comes from North Carolina and Florida. The remaining U.S. production is chiefly from Idaho, Montana, Utah and Wyoming. Phosphate rock mined in Florida has higher proportions of Fe, Al, Mg, and other impurities than in the past. Western phosphates contain high proportions of these impurities. This has resulted in substantial problems in beneficiation and wet-process phosphoric acid production.
[Farm Chemicals Handbook 1998. Willoughby, OH: Meister Publishing Co., 1998.,p. B33]**PEER REVIEWED**

Formulations/Preparations:

COMMERCIAL PHOSPHORIC ACID, CONTAINING 68.8% OR LESS OF PHOSPHORIC ANHYDRIDE, IS COMPOSED ONLY OF MONOMERIC PHOSPHORIC ACID, H3PO4. ... COMMERCIAL COMPOSITIONS CONTAINING MORE THAN 68.8% PHOSPHORIC ANHYDRIDE CONTAIN INCREASING QUANTITIES OF POLYMERS OF PHOSPHORIC ACID.
[Furia, T.E. (ed.). CRC Handbook of Food Additives. 2nd ed. Cleveland: The Chemical Rubber Co., 1972. 619]**PEER REVIEWED**

PURE SOLID PHOSPHORIC ACID CONTAINS 72.44% PHOSPHORIC ANHYDRIDE. MAX CONCN OF LIQ PHOSPHORIC ACID IS 88% PHOSPHORIC ACID, OR 63.75% PHOSPHORIC ANHYDRIDE.
[Farm Chemicals Handbook 1991. Willoughby, OH: Meister, 1991.,p. B-47]**PEER REVIEWED**

Polyphosphoric acid (mixture of orthophosphoric acid with pyrophosphoric, triphosphoric, and higher acids and is sold on the basis of its calculated HsPO4 content, e.g.; 115% phosphoric acid. Super phosphoric acid is a similar mixtur solid at 105% HsPO4.
[Lewis, R.J., Sr (Ed.). Hawley's Condensed Chemical Dictionary. 12th ed. New York, NY: Van Nostrand Rheinhold Co., 1993 940]**PEER REVIEWED**

WET-PROCESS ACID, MERCHANT GRADE, HAS MIN ASSAY OF 53.1%; PURIFIED WET-PROCESS ACID, TECH GRADE, HAS MIN ASSAY OF 54%; THERMAL ACID, TECH GRADE, HAS MIN ASSAY OF 54.32%
[Kirk-Othmer Encyclopedia of Chemical Technology. 3rd ed., Volumes 1-26. New York, NY: John Wiley and Sons, 1978-1984.,p. V17 435 (1982)]**PEER REVIEWED**

WET ACID (MERCHANT GRADE) IS 53-54% PHOSPHORIC ANHYDRIDE AND SUPERACID GRADE IS 68-70% PHOSPHORIC ANHYDRIDE.
[Farm Chemicals Handbook 1991. Willoughby, OH: Meister, 1991.,p. B-46]**PEER REVIEWED**

Reagent grade concentrated phosphoric acid is 85-87% (wt/wt) phosphoric acid (equivalent to about 17 M).
[Gosselin, R.E., R.P. Smith, H.C. Hodge. Clinical Toxicology of Commercial Products. 5th ed. Baltimore: Williams and Wilkins, 1984.,p. II-101]**PEER REVIEWED**

Impurities:

THE FOLLOWING CHEMICALS APPEAR AS IMPURITIES IN WET-PROCESS ACID-MERCHANT GRADE, PURIFIED WET-PROCESS ACID TECHNICAL GRADE, AND THERMAL ACID-TECHNICAL GRADE, RESPECTIVELY: CALCIUM MONOXIDE-0.06%, 0.005%, 0.01%; FLUORIDE-0.8%, 0.08%, <0.0001%; ALUMINUM OXIDE-1.7%, 0.01%, 0.0003%; IRON OXIDE-1.23%, 0.007%, 0.004%; MAGNESIUM OXIDE-0.58%, 0.003%, 0.0002%; POTASSIUM OXIDE-0.01%, 0%, 0.0007%; SODIUM OXIDE-0.12%, 0.0025%; SILICON DIOXIDE-0.07%, 0.1%, 0.0015%; AND SULFATE-2.2%, 0.2%, >0.002%
[Kirk-Othmer Encyclopedia of Chemical Technology. 3rd ed., Volumes 1-26. New York, NY: John Wiley and Sons, 1978-1984.,p. 17 435 (1982)]**PEER REVIEWED**

Consumption Patterns:

75% IN MANUFACTURE OF FERTILIZERS; 8% FOR MANUFACTURE OF AGRICULTURAL FEEDS; 11% FOR BUILDERS AND WATER TREATMENT (USED IN DETERGENTS, PRE-SOAKS AND CLEANSERS); 2.5% IN PRODUCTION OF FOODS, BEVERAGES, PET FOODS, AND DENTIFRICES; 1% IN DIRECT ACID TREATMENT OF METAL SURFACES; 2.5% FOR MANUFACTURE OF FIRE CONTROL AGENTS, ANTIFREEZE, CATALYSTS, DRILLING MUDS, AND PHOSPHORS, AND FOR REFRACTORIES, TEXTILES AND OTHER MISC USES (1973)
[SRI]**PEER REVIEWED**

END USE PATTERN-DERIVATIVE: FERTILIZERS, 89%; ANIMAL FEEDS, 4%; DETERGENTS & WATER TREATMENT, 3%; FOOD & BEVERAGES, 2%; METAL TREATMENTS, 1%; MISC, 1% (1983)
[CHEMICAL PRODUCTS SYNOPSIS: PHOSPHORIC ACID, 1983]**PEER REVIEWED**

Phosphoric acid. Diammonium phosphate, 20%; merchant shipments (for feed, industrial and blending applications), 10%; superphosphoric acid (SPA), 7%; monoammonium phosphate (MAP), 5.5%; triple-superphosphate (TSP), 4%; dry fertilizer exports, 41% (including 75% diammonium phosphate, 20% TSP, 5% MAP); SPA exports, 7.5%; phosphoric acid exports, 4%; miscellaneous, 1%.
[Kavaler AR; Chemical Marketing Reporter 230 (10): 54 (1986)]**PEER REVIEWED**

Phosphoric acid. Diammonium phosphate 49%; superphosphoric acid, 15%; monoammonium phosphate, 10%; triple superphosphate, 8%; merchant shipments (including industrial and blending applications), 6%; phosphoric acid export, 5%; animal feed, 4%; miscellaneous, 3%.
[Kavaler AR; Chemical Marketing Reporter 236 (9): 50 (1989)]**PEER REVIEWED**

Builders and water treatment, 15%; foods, 13%; metals, 17%; others, 55%. /Industrial-grade phosphoric acid/
[SRI. 1997 Directory of Chemical Producers - United States of America. Menlo Park, CA: SRI International 1997. 808]**PEER REVIEWED**

U. S. Production:

(1972) 5.99X10+12 GRAMS
[SRI]**PEER REVIEWED**

(1975) 6.97X10+12 GRAMS
[SRI]**PEER REVIEWED**

(1984) 1.03X10+13 g
[BUREAU OF THE CENSUS. CURRENT INDUSTRIAL REPORTS: INORGANIC CHEMICALS 1984 p.13]**PEER REVIEWED**

Production by wet process was 10.947 tons and by the furnace process 0.611 million short tons in 1989.
[Farm Chemicals Handbook 1991. Willoughby, OH: Meister, 1991.,p. B-46]**PEER REVIEWED**

(1990) 24.07 billion lb
[Chem & Engineering News 70 (15): 17 (4/13/92)]**PEER REVIEWED**

(1991) 24.11 billion lb
[Chem & Engineering News 71 (15): 11 (4/12/93)]**PEER REVIEWED**

(1991) 1.3058X10+7 metric tons
[SRI. 1992 Directory of Chemical Producers-United States of America. Menlo Park, CA: SRI International, 1992. 850]**PEER REVIEWED**

(1992) 25.58 billion lb
[Chem & Engineering News 72 (15): 13 (4/11/94)]**PEER REVIEWED**

(1993) 23.04 billion lb
[Chem & Engineering News 72 (15): 13 (4/11/94)]**PEER REVIEWED**

Annual production capacity estimate as of 4/1/97 (P2O5 content basis): 11,080 thousand metric tons.
[SRI. 1997 Directory of Chemical Producers - United States of America. Menlo Park, CA: SRI International 1997. 808]**PEER REVIEWED**

Industrial-grade (thousands of tons/yr): 1991: 636; 1992: 555; 1993: 570.
[Kirk-Othmer Encyclopedia of Chemical Technology. 4th ed. Volumes 1: New York, NY. John Wiley and Sons, 1991-Present.,p. V18 715]**PEER REVIEWED**

Wet-process agricultural (thousands of tons/yr): 1991: 9,300; 1992: 10,179; 1993: 8,532.
[Kirk-Othmer Encyclopedia of Chemical Technology. 4th ed. Volumes 1: New York, NY. John Wiley and Sons, 1991-Present.,p. V18 715]**PEER REVIEWED**

Phosphoric acid. Demand: 1988-1989 (fertilizer year): 11.0 million tons; 1989-1990: 11.2 million tons; 1993-1994 /projected/: 12.0 million tons. (Includes exports, but not imports, which are negligible.)
[Kavaler AR; Chemical Marketing Reporter 236 (9): 50 (1989)]**PEER REVIEWED**

Phosphoric acid. Demand: 1985: 10.1 million short tons; 1986: 9.4 million short tons; 1990 /projected/: 10.9 million short tons.
[Kavaler AR; Chemical Marketing Reporter 230 (10): 54 (1986)]**PEER REVIEWED**

U. S. Imports:

(1972) 5.44X10+10 GRAMS
[SRI]**PEER REVIEWED**

(1974) 3.63X10+10 GRAMS
[SRI]**PEER REVIEWED**

U. S. Exports:

(1972) 2.0X10+10 GRAMS
[SRI]**PEER REVIEWED**

(1974) 8.63X10+10 GRAMS
[SRI]**PEER REVIEWED**

(1984) 1.35X10+10 G/OTHER THAN FERTILIZER GRADE/
[BUREAU OF THE CENSUS. U.S. EXPORTS, SCHEDULE E, 1984 p.2-89]**PEER REVIEWED**

Laboratory Methods:

Clinical Laboratory Methods:

NIOSH Method 215. Analyte: Inorganic phosphate. Specimen: Urine. Procedure: Spectrophotometry. For inorganic phosphate this method has an estimated detection limit of 0.06 mg/ml/sample. the presision/RSD is 0.07 and the recovery is not given. The working range is 0.6 to 6 mg/ml for a 25 ul sample. Interferences: Arsenate and silicate will interfere at higher concentrations. Barium, lead, mercury, and silver can interfere by forming a precipitate. /Inorganic phosphate/
[U.S. Department of Health and Human Services, Public Health Service. Centers for Disease Control, National Institute for Occupational Safety and Health. NIOSHManual of Analytical Methods, 3rd ed. Volumes 1 and 2 with 1985 supplement, and revisions. Washington, DC: U.S. Government Printing Office, February 1984.,p. 215-1]**PEER REVIEWED**

Analytic Laboratory Methods:

Colorimetric methods may be used to detect 1-20 mg/l in water.
[Environment Canada; Tech Info for Problem Spills: Phosphoric Acid (Draft) p.83 (1981)]**PEER REVIEWED**

Colorimetric methods may be used to detect 0-20 ppm in soil.
[Environment Canada; Tech Info for Problem Spills: Phosphoric Acid (Draft) p.84 (1981)]**PEER REVIEWED**

NIOSH Method: 216. Analyte: Phosphoric acid. Matrix: Air. Procedure: Spectrophotometric determination of phosphate. Method Evaluation: Method was validated over the range of 0.2 to 4.0 mg/cu m using a 50-liter sample. Method detection limit: 2 ug. Precision (CVt): 0.043. Interferences: Phosphate salts will cause the results for phosphoric acid to be high. Arsenates, if present in sufficiently high amounts, will give high results.
[U.S. Department of Health, Education Welfare, Public Health Service. Center for Disease Control, National Institute for Occupational Safety Health. NIOSH Manual ofAnalytical Methods. 2nd ed. Volumes 1-7. Washington, DC: U.S. Government Printing Office, 1977-present.,p. 216-1]**PEER REVIEWED**

NIOSH Method: S333. Analyte: Phosphoric acid. Matrix: Air. Procedure: Colorimetric. Method Evaluation: Method was validated over the range of 0.47 to 1.93 mg/cu m using a 90/liter sample. Precision (CVt): 0.055. Applicability: Under the conditions of sample size (90/liter) the useful range is 0.10 to 2.0 mg/cu m. Interference: Airborne particulate salts of phosphoric acid will interfere with this determination.
[U.S. Department of Health, Education Welfare, Public Health Service. Center for Disease Control, National Institute for Occupational Safety Health. NIOSH Manual ofAnalytical Methods. 2nd ed. Volumes 1-7. Washington, DC: U.S. Government Printing Office, 1977-present.,p. S333-1]**PEER REVIEWED**

NIOSH Method 7903. Acids, Inorganic. Analyte: Orthophosphoric acid. Matrix: Air. Procedure: Ion chromatography. For orthophosphoric acid this method has an estimated detection limit of 2 ug/sample. The precision/RSD is 0.029 and the recovery is not given. Applicability: The working range is ca. 0.01 to 5 mg/cu m for a 50 liter air sample. Interferences: Particulate salts of all the acids will give a positive interference.
[U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health. NIOSH Manual of Analytical Methods. 4th ed.Methods A-Z & Supplements. Washington, DC: U.S. Government Printing Office, Aug 1994.,p. 7903-1]**PEER REVIEWED**

Sampling Procedures:

Determination in air: Collection on a cellulose membrane filter for colorimetric determination.
[Sittig, M. Handbook of Toxic And Hazardous Chemicals. Park Ridge, NJ: Noyes Data Corporation, 1981. 543]**PEER REVIEWED**

NIOSH Method 7903. Analyte: Orthophosphoric acid. Matrix: Air. Sampler: Solid sorbent tube (washed silica gel, 400 mg/200 mg with glass fiber filter plug). Flow Rate: 0.2 to 0.5 l/min: Sample Size: 50 liters. Shipment: Routine. Sample Stability: Stable.
[U.S. Department of Health and Human Services, Public Health Service. Centers for Disease Control, National Institute for Occupational Safety and Health. NIOSHManual of Analytical Methods, 3rd ed. Volumes 1 and 2 with 1985 supplement, and revisions. Washington, DC: U.S. Government Printing Office, February 1984.,p. 7903-1]**PEER REVIEWED**

NIOSH Method S333. Analyte: Phosphoric acid. Matrix: Air. Procedure: Filter collection, water leach, complex formation. Flow Rate: 1.5 l/min. Sample Size: 90 liters.
[U.S. Department of Health, Education Welfare, Public Health Service. Center for Disease Control, National Institute for Occupational Safety Health. NIOSH Manual ofAnalytical Methods. 2nd ed. Volumes 1-7. Washington, DC: U.S. Government Printing Office, 1977-present.,p. S333-1]**PEER REVIEWED**

NIOSH Method 216. Analyte: Phosphoric acid. Matrix: Air. Procedure: Collection on a membrane filter. Flow Rate: 1.5 l/min. Sample Size: 50 liter.
[U.S. Department of Health, Education Welfare, Public Health Service. Center for Disease Control, National Institute for Occupational Safety Health. NIOSH Manual ofAnalytical Methods. 2nd ed. Volumes 1-7. Washington, DC: U.S. Government Printing Office, 1977-present.,p. 216-1]**PEER REVIEWED**

NIOSH Method 7300. Analyte: Phosphorus. Matrix: Air. Sampler: Filter (0.8 um, cellulose ester membrane). Flow Rate: 1 to 4 l/min. Sample Size: 500 liters. Shipment: Routine. Sample Stability: Stable. /Phosphorus/
[U.S. Department of Health and Human Services, Public Health Service. Centers for Disease Control, National Institute for Occupational Safety and Health. NIOSHManual of Analytical Methods, 3rd ed. Volumes 1 and 2 with 1985 supplement, and revisions. Washington, DC: U.S. Government Printing Office, February 1984.,p. 7300-1]**PEER REVIEWED**

Special References:

Special Reports:

Environment Canada; Tech Info for Problem Spills: Phosphoric Acid (Draft) (1982)

WHO; Diseases Caused by Phosphorus and Its Toxic Compounds; Early Detection of Occupational Diseases pg 53-62 (1986). Review of diseases and health related effects resulting from exposure to phosphorus or phosphorus cmpd.

MARTIN EE; DEVELOPMENT DOCUMENT FOR EFFLUENT LIMITATIONS GUIDELINES AND NEW SOURCE PERFORMANCE STANDARDS FOR PHOSPHORUS DERIVED CHEMICALS SEGMENT OF THE PHOSPHATE MANUFACTURING POINT SOURCE CATEGORY; US NTIS, PB REP: 158 PAGES (1974) ISS 241018. A STUDY WAS MADE OF THE PHOSPHATE MANUFACTURING POINT SOURCE CATEGORY FOR THE PURPOSE OF DEVELOPING EFFLUENT LIMITATIONS GUIDELINES, FEDERAL STANDARDS OF PERFORMANCE, AND PRETREATMENT STANDARDS FOR THE INDUSTRY. EFFLUENT LIMITATIONS GUIDELINES WERE DEVELOPED, DEFINING THE DEGREE OF EFFLUENT REDUCTION ATTAINABLE THROUGH THE APPLICATION OF THE BEST PRACTICABLE CONTROL TECHNOLOGY CURRENTLY AVAILABLE AND THE BEST AVAILABLE TECHNOLOGY ECONOMICALLY ACHIEVABLE. THE STANDARDS OF PERFORMANCE FOR NEW SOURCES WERE ALSO DEFINED. PROCESSES, WASTES, AND COSTS ARE ALSO DISCUSSED.

Synonyms and Identifiers:

Synonyms:

ACIDE PHOSPHORIQUE (FRENCH)
**PEER REVIEWED**

ACIDO FOSFORICO (ITALIAN)
**PEER REVIEWED**

EVITS
**PEER REVIEWED**

FOSFORZUUROPLOSSINGEN (DUTCH)
**PEER REVIEWED**

ORTHOPHOSPHORIC ACID
**PEER REVIEWED**

Ortho-Phosphoramide
**PEER REVIEWED**

o-Phosphoric acid
**PEER REVIEWED**

PHOSPHORSAEURELOESUNGEN (GERMAN)
**PEER REVIEWED**

SONAC
**PEER REVIEWED**

WC-REINIGER
**PEER REVIEWED**

White phosphoric acid
**PEER REVIEWED**

Associated Chemicals:

Pyrophosphoric acid;2466-09-3

Formulations/Preparations:

COMMERCIAL PHOSPHORIC ACID, CONTAINING 68.8% OR LESS OF PHOSPHORIC ANHYDRIDE, IS COMPOSED ONLY OF MONOMERIC PHOSPHORIC ACID, H3PO4. ... COMMERCIAL COMPOSITIONS CONTAINING MORE THAN 68.8% PHOSPHORIC ANHYDRIDE CONTAIN INCREASING QUANTITIES OF POLYMERS OF PHOSPHORIC ACID.
[Furia, T.E. (ed.). CRC Handbook of Food Additives. 2nd ed. Cleveland: The Chemical Rubber Co., 1972. 619]**PEER REVIEWED**

PURE SOLID PHOSPHORIC ACID CONTAINS 72.44% PHOSPHORIC ANHYDRIDE. MAX CONCN OF LIQ PHOSPHORIC ACID IS 88% PHOSPHORIC ACID, OR 63.75% PHOSPHORIC ANHYDRIDE.
[Farm Chemicals Handbook 1991. Willoughby, OH: Meister, 1991.,p. B-47]**PEER REVIEWED**

Polyphosphoric acid (mixture of orthophosphoric acid with pyrophosphoric, triphosphoric, and higher acids and is sold on the basis of its calculated HsPO4 content, e.g.; 115% phosphoric acid. Super phosphoric acid is a similar mixtur solid at 105% HsPO4.
[Lewis, R.J., Sr (Ed.). Hawley's Condensed Chemical Dictionary. 12th ed. New York, NY: Van Nostrand Rheinhold Co., 1993 940]**PEER REVIEWED**

WET-PROCESS ACID, MERCHANT GRADE, HAS MIN ASSAY OF 53.1%; PURIFIED WET-PROCESS ACID, TECH GRADE, HAS MIN ASSAY OF 54%; THERMAL ACID, TECH GRADE, HAS MIN ASSAY OF 54.32%
[Kirk-Othmer Encyclopedia of Chemical Technology. 3rd ed., Volumes 1-26. New York, NY: John Wiley and Sons, 1978-1984.,p. V17 435 (1982)]**PEER REVIEWED**

WET ACID (MERCHANT GRADE) IS 53-54% PHOSPHORIC ANHYDRIDE AND SUPERACID GRADE IS 68-70% PHOSPHORIC ANHYDRIDE.
[Farm Chemicals Handbook 1991. Willoughby, OH: Meister, 1991.,p. B-46]**PEER REVIEWED**

Reagent grade concentrated phosphoric acid is 85-87% (wt/wt) phosphoric acid (equivalent to about 17 M).
[Gosselin, R.E., R.P. Smith, H.C. Hodge. Clinical Toxicology of Commercial Products. 5th ed. Baltimore: Williams and Wilkins, 1984.,p. II-101]**PEER REVIEWED**

Shipping Name/ Number DOT/UN/NA/IMO:

IMO 8.0; Phosphoric acid

UN 1805; Phosphoric acid

Standard Transportation Number:

49 302 48; Phosphoric acid

RTECS Number:

NIOSH/TB6300000

Administrative Information:

Hazardous Substances Databank Number: 1187
Last Revision Date: 20020806
Last Review Date: Reviewed by SRP on 1/31/1999

Great Lakes Chemical Corporation and the Pathfinders Camp