Potassium nitrite

85.1

84.957

231-832-4

794654G42L

1069

1488

DTXSID5042320

White or slightly yellow granules or rods|White crystals

28341000

52.5

0.25060

White to slightly yellow Solid

1.915 g/cm³

441 °C (decomp)

537 deg C (explodes)

soluble in water, hot alcohol, liquid NH{3}soluble in water, alcohol and ammonia.

Store at +5°C to +30°C.

Oral-Rabbit LD50: 200 mg/kg

Thermal decomposition of toxic nitrogen oxide gas

6,0-9,0 (5 % solution)

The hydrate exists below -8.9 °C|Deliquescent

Water soluble.

Nitrate and Nitrite Compounds, Inorganic

Strong Oxidizing Agent

POTASSIUM NITRITE is an oxidizing agent. Mixtures with phosphorus, tin(II) chloride or other reducing agents may react explosively [Bretherick 1979 p. 108-109]. Contamination by ammonium compounds can initiate spontaneous decomposition. The resulting heat may ignite surrounding combustible material. Reacts with acids to form toxic nitrogen dioxide gas. Mixing with liquid ammonia forms dipotassium nitrite, which is very reactive and easily explosive [Mellor 2, Supp. 3:1566 1963]. Melting together with an ammonium salt leads to a violent explosion [Von Schwartz 1918 p. 299]. A mixture with potassium cyanide may cause an explosion. When a little ammonium sulfate is added to fused potassium nitrite, a vigorous reaction occurs attended by flame [Mellor 2:702. 1946-47].

II

5.1

UN 1488 5.1/PG 2

2

8-25-50

45-61

TT3750000

O,T,N

The warehouse is ventilated, low temperature and dry; lightly loaded and unloaded; stored separately from organic materials, reducing agents, sulfur, phosphorus and flammable materials, food raw materials

Mixed with reducing agent, sulfur, phosphorus, etc., heated, impacted, friction can be explosive

Stability Stable, but strong oxidizer - contact with combustible material may lead to fire. Incompatible with strong reducing agents, strong acids, combustible materials, cyanides, ammonium salts.

P210, P220, P221, P264, P270, P273, P280, P301+P310, P321, P330, P370+P378, P391, P405, P501

H272

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational exposure or environmental contamination. Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in soil or water; effects on animal, aquatic, and plant life; and conformance with environmental and public health regulations.

Addition of ammonium sulfate to the fused /potassium/ nitrite causes effervescence and ignition.|molten potassium nitrite is violently decomposed by boron.|It will explode at 1000 °F or when mixed with cyanide salts & heated.|... Reacts violently with potassium amide and heat.|For more Hazardous Reactivities and Incompatibilities (Complete) data for POTASSIUM NITRITE (9 total), please visit the HSDB record page.

Sodium nitrite and potassium nitrite are subject to prior sanctions issued by the U.S. Department of Agriculture for use as color fixatives and preservative agents, with or without sodium or potassium nitrate, in the curing of red meat and poultry products.

WHO; WHO Food Additives Series 35 (844): Nitrite provides a summary of the background materials used by JECFA to determine an ADI for nitrite.

Excerpt from ERG Guide 140 [Oxidizers]: These substances will accelerate burning when involved in a fire. Some may decompose explosively when heated or involved in a fire. May explode from heat or contamination. Some will react explosively with hydrocarbons (fuels). May ignite combustibles (wood, paper, oil, clothing, etc.). Containers may explode when heated. Runoff may create fire or explosion hazard. (ERG, 2016)|Not combustible but enhances combustion of other substances. Many reactions may cause fire or explosion. Gives off irritating or toxic fumes (or gases) in a fire.

|Danger|H272: May intensify fire; oxidizer [Danger Oxidizing liquids; Oxidizing solids]|P210, P220, P221, P264, P270, P273, P280, P301+P310, P321, P330, P370+P378, P391, P405, and P501|H272 (100%): May intensify fire; oxidizer [Danger Oxidizing liquids; Oxidizing solids]|P210, P220, P221, P264, P270, P273, P280, P301+P310, P302+P352, P312, P321, P322, P330, P361, P363, P370+P378, P391, P405, and P501|Aggregated GHS information provided by 302 companies from 5 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.|P201, P202, P210, P220, P221, P260, P263, P264, P270, P280, P281, P307+P311, P308+P313, P321, P370+P378, P405, and P501|Warning|P201, P202, P210, P220, P221, P260, P261, P264, P270, P271, P280, P281, P302+P352, P304+P312, P304+P340, P305+P351+P338, P308+P313, P309+P311, P312, P321, P332+P313, P337+P313, P362, P370+P378, P403+P233, P405, and P501

Excerpt from ERG Guide 140 [Oxidizers]: As an immediate precautionary measure, isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids. LARGE SPILL: Consider initial downwind evacuation for at least 100 meters (330 feet). 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. (ERG, 2016)

Excerpt from ERG Guide 140 [Oxidizers]: Keep combustibles (wood, paper, oil, etc.) away from spilled material. Do not touch damaged containers or spilled material unless wearing appropriate protective clothing. Stop leak if you can do it without risk. Do not get water inside containers. SMALL DRY SPILL: With clean shovel, place material into clean, dry container and cover loosely; move containers from spill area. SMALL LIQUID SPILL: Use a non-combustible material like vermiculite or sand to soak up the product and place into a container for later disposal. LARGE SPILL: Dike far ahead of liquid spill for later disposal. Following product recovery, flush area with water. (ERG, 2016)

Excerpt from ERG Guide 140 [Oxidizers]: Wear positive pressure self-contained breathing apparatus (SCBA). Wear chemical protective clothing that is specifically recommended by the manufacturer. It may provide little or no thermal protection. Structural firefighters' protective clothing will only provide limited protection. (ERG, 2016)|... Eye protection in combination with breathing protection ... Extra personal protection: P3 filter respirator for toxic particles.|Personnel protectioin: ... Wear appropriate chemical protective gloves, boots and goggles.

Not combustible but enhances combustion of other substances ... /Potassium nitrite/ is a strong oxidant and reacts with combustible and reducing materials causing fire and explosion hazard.|Moderate; Oxidizing material.

May explode on heating above 530 °C ... /Potassium nitrite/ is a strong oxidant and reacts with combustible and reducing materials causing fire and explosion hazard.|Prolonged exposure to fire or heat may result in an explosion.

Evacuation: If fire becomes uncontrollable - consider evacuation of one-half (1/2) mile radius|If material on fire or involved in fire: Flood with water. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible.|... All extinguishing agents allowed.

Evaporation at 20 °C is negligible; a harmful concentration of airborne particles can, however, be reached quickly.

Sweep spilled substance into containers. Carefully collect remainder, then remove to safe place. Do NOT absorb in saw-dust or other combustible absorbents. Do NOT let this chemical enter the environment. (Extra personal protection: P3 filter respirator for toxic particles).

If material not on fire and not involved in fire: Keep sparks, flames, and other sources of ignition away. Keep material out of water sources and sewers.|Personnel protection: Avoid breathing dusts. ... Do not handle broken packages unless wearing appropriate personal protective equipment. Wash away any material which may have contacted the body with copious amounts of water or soap and water. Wear positive pressure self-contained breathing apparatus when fighting fires involving this material.|NO contact with combustibles ... PREVENT DISPERSION OF DUST ... Local exhaust or breathing protection ... Do not eat, drink, or smoke during work. Wash hands before eating ... Depending on the degree of exposure, periodic medical examination is indicated. Specific treatment is necessary in case of poisoning with this substance; the appropriate means with instructions must be available. Rinse contaminated clothes (fire hazard) with plenty of water.|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.|Approximately 14 million households in the United States use private wells to supply their drinking water (Bureau of the Census 1993). In agricultural areas, nitrogen-based fertilizers are a major source of contamination for shallow groundwater aquifers that provide drinking water. A recent United States Geological Survey study showed that >8,200 wells nationwide were contaminated with nitrate levels above the U.S. Environmental Protection Agency (EPA) drinking water standard of 10 parts per million (ppm). ... Because of the risks for potential adverse health effects, persons who use drinking water that contains nitrate levels >10 milligrams per liter (mg/L) should have alternative sources of water or appropriate treatment of existing supplies. Information regarding testing of well water can be obtained from city or county health departments. Other sources of nitrate contamination are organic animal wastes and contamination from septic sewer systems, especially in wells <100 feet deep. During spring melt or drought conditions, both domestic wells and public water systems using surface water can show increased nitrate levels. /Nitrate/

/GUIDE 140: OXIDIZERS/ Fire or Explosion: These substances will accelerate burning when involved in a fire. Some may decompose explosively when heated or involved in a fire. May explode from heat or contamination. Some will react explosively with hydrocarbons (fuels). May ignite combustibles (wood, paper, oil, clothing, etc.). Containers may explode when heated. Runoff may create fire or explosion hazard.|/GUIDE 140: OXIDIZERS/ Health: Inhalation, ingestion or contact (skin, eyes) with vapors or substance may cause severe injury, burns or death. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may cause pollution.|/GUIDE 140: OXIDIZERS/ Public Safety: CALL Emergency Response Telephone Number on Shipping Paper first. If Shipping Paper not available or no answer, refer to appropriate telephone number listed on the inside back cover. As an immediate precautionary measure, isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids. Keep unauthorized personnel away. Stay upwind. Keep out of low areas. Ventilate closed spaces before entering.|/GUIDE 140: OXIDIZERS/ Protective Clothing: Wear positive pressure self-contained breathing apparatus (SCBA). Wear chemical protective clothing that is specifically recommended by the manufacturer. It may provide little or no thermal protection. Structural firefighters' protective clothing will only provide limited protection.|For more DOT Emergency Guidelines (Complete) data for POTASSIUM NITRITE (8 total), please visit the HSDB record page.

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)./|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.|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.

... /Potassium nitrite/ is irritating to the eyes, the skin and the respiratory tract.

Personal protection: particulate filter respirator adapted to the airborne concentration of the substance. Do NOT let this chemical enter the environment. Sweep spilled substance into covered containers. Carefully collect remainder. Then store and dispose of according to local regulations. Do NOT absorb in saw-dust or other combustible absorbents.

Fireproof. Provision to contain effluent from fire extinguishing. Separated from combustible substances, reducing agents and acids. Dry. Well closed.

Evaporation at 20 °C is negligible; a harmful concentration of airborne particles can, however, be reached quickly.

The substance is irritating to the eyes, skin and respiratory tract. The substance may cause effects on the cardiovascular system and blood. This may result in fall of blood pressure and the formation of methaemoglobin. Exposure could cause death. The effects may be delayed. Medical observation is indicated.

NO contact with combustible substances.

PREVENT DISPERSION OF DUST!

Use local exhaust or breathing protection.

Protective gloves.

Wear safety goggles or eye protection in combination with breathing protection.

The major hazards encountered in the use and handling of potassium nitrite stem from its toxicologic properties and reactivity. Toxic by all routes (ie, inhalation, ingestion, or dermal contact), exposure to this white-to-yellowish, crystalline substance may occur from its use as a color fixative and preservative in meats, in analytical chemistry, and in organic synthesis. Effects from exposure may include burns to the skin and eyes, headache, nausea, or methemoglobinemia. In activities and situations where over-exposure may occur, wear personal protective clothing and a self-contained breathing apparatus. If exposure should occur, immediately flush affected skin and eyes with running water for at least 15 minutes. Remove contaminated clothing and shoes at the site. Potassium nitrite is an oxidizer and may ignite combustible materials (wood, paper, oil, etc.). With fuels, the reaction may be violent. Also, prolonged exposure to heat or fire may result in an explosion, with the production of poisonous gases. For fires involving potassium nitrite, extinguish with dry chemical, CO2, Halon, water spray, or fog. If water is used, apply from as far a distance as possible. If fire becomes uncontrollable, consider evacuation of one-half mile radius. Potassium nitrite should be kept in airtight containers and stored away from combustibles and sources of ignition. Potassium nitrite may be shipped via air, rail, road, and water, in containers bearing the label, "Oxidizer." For small spills of potassium nitrite, place material into a clean, dry, covered container. For large spills of potassium nitrite solutions, first dike far ahead of the spill to prevent it from entering water sources and sewers, then take up with sand, earth, or other noncombustible absorbent material.

highly

Methylene blue has a protective effect against nitrite-induced MetHb formation ... Dietary factors may have a protective effect against MetHb formation. Examples are ascorbic acid (vitamin C) and methionine which reduced the level of nitrite-induced MetHb when added to the diet of guinea-pigs. Conversely, guinea-pigs deficient in ascorbic acid had higher nitrite-induced MetHb levels than control animals ... /Nitrite/|The effect of nitrite ingestion on the intestinal deconjugation and absorption of folic acid (PGA) and brewers yeast folate was investigated using a rat bioassay and liver folate uptake as the response parameter. Male weanling Sprague Dawley rats were depleted on a low folate AIN-76A formulated basal diet for 21 days. During a 14 day repletion period, folic acid (PGA) and brewers yeast were added to provide 0.25, 0.5 and 1.0 mg of folate per kg of diet. Potassium nitrite was administered as part of the diet at 0.5%. All diets were made isonitrogenous and isocaloric. Based on a parallel line assay, the relative bioavailability of folate in the brewers yeast diet (109) was significantly higher than in the standard diet (PGA = 100). When combined with nitrite, the relative bioavailability of the PGA diet was not significantly different (101), while that of the brewers yeast diet was significantly lower than the standard diet. Concomitant ingestion of nitrite significantly reduced the bioavailability of brewers yeast folate but not that of PGA in rats. This appeared to be a direct effect of oxidation by nitrite on the more susceptible substituted folates in brewers yeast.|... In vivo formation of nitrosopiperidine /was demonstrated/ in the stomach of rats from nitrate and piperidine. At comparable doses, a lesser degree of nitrosation occurred with nitrite and piperidine. /Nitrate and nitrite/|No increase was found in urinary nitrosamine levels of human subjects after consumption of meals with fish or beef (source of amines), bacon (source of pre-formed nitrosamines), in combination with spinach and vegetable juice (source of nitrate/nitrite). /Nitrate or nitrite/|For more Interactions (Complete) data for POTASSIUM NITRITE (6 total), please visit the HSDB record page.

LC50 Mouse inhalation 85 g/cu m/2 hr|LD50 Rabbit oral 108 mg anion/kg /Nitrite ion/

/AQUATIC SPECIES/ Salmo gairdneri /exposed/ to 0.1 mg NO2-/L for ... /7 wk/ in freshwater caused no lethality, growth reduction, gill histological changes or hematological dyscrasions ... Although 0.05 mg NO2-/L causes significant increase in methemoglobin levels, the change was slight and not of biological significance. /Nitrite/|/AQUATIC SPECIES/ Rainbow trout (Salmo gairdneri) appears to be the most sensitive fish species to nitrite toxicity, with a 96 hr LC50 ranging from 0.56 to 1.78 mg NO2-/L for low chloride water and 11.5 to 17.4 mg NO2-/L for high chloride water, at pH between 7.5 and 8.6 in hard water. /Nitrite/

Neonates are at special risk for high nitrate and nitrite levels as their enzyme system for regeneration of hemoglobin is not fully developed ... Most clinical case data refers to neonates developing methemoglobinemia after drinking water or water-based formulations with high nitrate or nitrite content ... Cases of methemoglobinemia have also been reported due to feeding babies vegetable preparations where nitrate has been converted to nitrite through bacterial action. /Nitrate and nitrite poisoning/|The lowest acute oral lethal dose of nitrite reported for man varied from 27 to 255 mg/kg, in which the lowest figures applied for children and elderly people. Nitrite is also more toxic to young infants (3 mo) than adults giving rise to relatively higher methemoglobin levels in the blood ... Individuals with stomach lesions or disorders ... /and/ persons on cimetidine and other antacid medication present special risk groups in which a correlation between nitrate or nitrite intake and incidence of gastric cancer cannot be excluded. /Nitrate and nitrite/|Aside from infants under 3 months of age, several other categories of individuals with altered physiological status or with hereditary or acquired disease may also be predisposed to the development of nitrite- or nitrate-induced methaemoglobinaemia. These include pregnant women ... individuals with glucose-6-phosphate dehydrogenase deficiency ... adults with reduced gastric acidity (including those being treated for peptic ulcer or individuals with chronic gastritis or pernicious anaemia), a rare group with a hereditary lack of NADH or methaemoglobin reductase activity in their red blood cells ... and probably the elderly ... Individuals with hereditary structural abnormalities in hemoglobin, referred to as hemoglobin Ms, are probably also at increased risk from dietary nitrate or nitrite. /Nitrate and nitrite/|Atrophic gastritis is a relevant factor in determining the gastric nitrite level, because nitrate administered to subjects with this type of gastritis results in a ten times higher nitrite concentration than that found in subjects with a normal mucosa. A given nitrate dose may be harmless to normal subjects, but harmful to a patient with atrophic gastritis, especially in the presence of precursors of N-nitrosamines or nitrosamides in the diet. /Nitrate and nitrite/|... Iron deficient patients with gastric lesions and patients with pernicious anemia (PA) are predisposed to stomach cancer and also have a high reduction rate of nitrate to nitrite. The reduction rates in PA patients were nearly 50-fold higher than of matched controls, as was the number of bacteria. /Nitrate and nitrite/

NIOSH (NOES Survey 1981-1983) has statistically estimated that 27,303 workers (2,845 of these are female) are potentially exposed to potassium nitrite in the US(1).|Potassium nitrite involved in poisonings: well water (contaminated), fertilizers /From table/|Oral intake of nitrate and nitrite in food and drinking water is the major route of entry /Nitrate and nitrite poisoning/|... /Potassium nitrite/ can be absorbed into the body by inhalation of its aerosol and by ingestion.

... Nitrite has vasodilating properties, probably through transformation into nitric oxide (NO) or a NO-containing molecule acting as a signal factor for smooth muscle relaxation ... /Nitrite/

... The lowest toxic dose reported was 1 mg NO2/kg, whereas in another study 0.5 to 5 mg NO2/kg did not cause any toxic effect ... /Nitrite/|The lethal oral dose of nitrite for adults has been variously reported to be between 0.7 and 6 g NO2- (approximately 10 to 100 mg NO2-/kg). /Nitrite/

Nitrate and nitrite given orally are absorbed and transferred to the blood in the upper part of the gastrointestinal tract. Abundant pectin in the food may delay absorption which may then occur lower down in the intestine, with possible increased risk for microbial transformation of nitrate into nitrite. /Nitrate and nitrite/|Regardless of route of exposure, nitrate and nitrite are rapidly transferred into the blood. Nitrite is gradually oxidized to nitrate which is readily distributed into most body fluids (urine, saliva, gastric juice, sweat, ileostomy fluid). Distribution of nitrate into plasma, erythrocytes, saliva and urine following an oral dose of sodium nitrate has been demonstrated ... Nitrate does not accumulate in the body. /Nitrate and nitrite/|Nitrite rapidly disappeared from a buffered solution at pH<5, simulating gastric conditions, and the rate of disappearance was enhanced by the presence of food ... Nitrite may also react with gastric contents (eg, nitrosation) or be reduced by the GI flora. A large part of nitrite entering the GI tract may thus disappear before absorption takes place ... Absorption of nitrite from the GI tract of rats was slower than that of nitrate. Forty five minutes after intragastric instillation of 13N-labelled nitrite, radioactivity was higher in the stomach and lower in the liver, kidneys, bladder and eviscerated carcass, than in similar experiments with 13N-labelled nitrate ... Nitrite was not absorbed from the caecum and large intestine of rats ... Gastric absorption of nitrite was noted in labelling and gastric emptying studies using rats and mice ... In rats, 63% of nitrite loss from the stomach was due to emptying and 37% to other processes ... Gastric absorption of nitrite seemed faster in mice than in rats. In vivo, the rate of absorption was about 4.5 times greater than the rate of chemical degradation. /Nitrite/|Nitrite is normally absent from the body fluids and tissues of laboratory animals ... The extensive pre-systemic metabolism of nitrite results in an absolute bioavailability (ie the percentage of the dose reaching the systemic circulation) considerably lower than 100%. Intravenous injections and intratracheal instillation of (13)N-labelled nitrite in mice and rabbits resulted in homogenous distribution of radioactivity in the heart, kidneys, liver, stomach, intestines, lungs and bladder (ranging from 4.2 to 10.5%) within 5 minutes. The (13)N was equally distributed in plasma and red blood cells with 15 to 20% of the plasma (13)N bound to proteins ... Thirty minutes after iv injection of nitrite, low levels of nitrite were detected in blood and saliva of dogs ... Nitrite can cross the placenta of rats and guinea-pigs: nitrite injected into pregnant animals appeared after a lag of approximately 20 minutes in fetal blood but at a lower concentration than in maternal blood ... /Nitrite/|For more Absorption, Distribution and Excretion (Complete) data for POTASSIUM NITRITE (6 total), please visit the HSDB record page.

... Intestinal bacteria were involved in the reduction of nitrite ... Absorbed nitrite is rapidly oxidized to nitrate in the blood by a mammalian process ... The process of nitrate generation parallels the methemoglobin (MetHb) formation ... Nitrite oxidation to nitrate may also occur in the stomach prior to absorption, as demonstrated in vitro for mice. However, under in vivo conditions, nitrite is probably absorbed from the stomach before large quantities of nitrate are formed. /Nitrite/|... Nitrite may be further reduced to nitrogen by bacteria under some conditions. In blood, nitrite transforms hemoglobin to methemoglobin and is simultaneously oxidized to nitrate. Normally methemoglobin gradually reverts to hemoglobin through enzymatic reactions. Nitrite has vasodilating properties, probably through transformation into nitric oxide (NO) or a NO-containing molecule acting as a signal factor for smooth muscle relaxation. Nitrite easily transforms into a nitrosating agent in an acidic environment and can react with a variety of compounds, eg ascorbic acid, amines, amides. Nitrosation can also be mediated by bacteria, eg in the stomach. Some reaction products are carcinogenic (eg most nitrosoamines and amides). /Nitrate and nitrite/|No or very slight increase in blood nitrosamine level was found in human subjects after consumption of nitrate-, nitrite-, and/or amine-rich meals /Nitrate, nitrite, and amine/|Nitrite may form nitroso compounds by reaction with a nitrosatable compound. Many different amino compounds including secondary and tertiary amines, secondary and tertiary amides, N-substituted ureas, guanidines, indoles (mainly tryptophan-bound in proteins) and urethanes, can act as nitrosatable compounds. In the case of amines, amides and ureas, the formed nitroso compounds are N-nitrosamines, N-nitrosoamides and N-nitrosoureas. The most common nitroso compounds are those derived from secondary amines. The rate of formation is often pH dependent and proportional to the concentration of unprotonated amine (inversely related to the basicity of the amine) and to the concentration of N2O3, and hence to the square of the NO2 concentration. An optimum pH in the range of 2.5 to 3.3 is commonly observed for N-nitrosamine formation ... Nitrosation occurs especially rapidly with weakly basic secondary amines (eg morpholine, piperazine, N-methylaniline), N-alkylureas, N-alkylcarbamates and aminopyrine. Nitrosation occurs relatively slowly with strongly basic amines, such as dimethylamine, and simple N-alkylamides. Nitrosation of tertiary amines, yielding dialkylnitrosamines and nitrosation of guanidines, yielding nitrosocyanamides and nitrosoureas occur relatively slowly. Catalysis of N-nitrosamine formation by nucleophilic anions at pH 2 to 5 has been widely observed. The catalytic order is SCN > I > Br > Cl > phosphate or carboxylate. Acceleration by SCN- and I- have attracted much attention because of their in vivo relevance: salivary SCN- levels are relatively high in smokers and I- is present in gastric secretion. Nitrosation of amides and related compounds is not catalyzed by nucleophilic anions. Effective inhibition of nitrosation requires materials which react readily with and convert the nitrosating agent to innocuous products, e.g.. compounds which either reduce HNO2 or NO or bind the NO+ group irreversibly. Sulfur dioxide and bisulfite ion, ascorbic acid, tocopherols, gallic acid, thiols, several dihydroxy phenols and some synthetic and natural antioxidants are inhibitors of nitrosation ... /It was/ demonstrated the endogenous formation of N-nitrosomorpholine from precursors (high amounts of nitrite and morpholine) by determination in the urine. Chinese tea inhibited this N-nitrosation which was attributed to the inhibitory effect of polyphenolic compounds and ascorbic acid present in tea ... A study with ascorbic acid showing that the inhibition of the formation of N-nitrosoproline was not complete. /Nitrite/

The two basic actions of sodium nitrite in vivo are relaxation of smooth muscle, especially of small blood vessels, and in toxic doses conversion of hemoglobin to methemoglobin. Same dual toxicity is shared by many inorganic ... nitrites S ... /Sodium nitrite/|The principal mechanism of nitrite toxicity is the oxidation of the ferrous iron (Fe2+) in deoxyhemoglobin to the ferric (Fe3+) valence state, producing methemoglobin. Methemoglobin cannot reversibly bind or transport circulating oxygen. Depending on the percentage of total methemoglobin in oxidized form, the clinical picture is one of oxygen deprivation with cyanosis, cardiac dysrhythmias and circulatory failure, and progressive central nervous system (CNS) effects. CNS effects can range from mild dizziness and lethargy to coma and convulsions. ... A chocolate-brown or slate-gray central cyanosis (involving the trunk and proximal portions of the limbs, as well as the distal extremities, mucous membranes, and lips) is one of the hallmarks of methemoglobinemia. This cyanosis is due to the dark chocolate-brown color of methemoglobin itself and can become noticeable at a concentration of 10% to 15% of total hemoglobin. /Nitrates and nitrites/|... The major concern of possible long-term effects of exposure to nitrate and nitrite is associated with formation of nitroso compounds, many of which are carcinogenic. This formation may take place wherever nitrite and nitrosable compounds are present, but it is favored by acidic conditions or the presence of some bacteria. The gastrointestinal tract and especially the stomach is regarded as the main formation site, but nitrosation reactions can also take place in an infected urinary bladder ... /Nitrate and nitrite poisoning/|Acute nitrate toxicity is almost always seen in infants rather than adults when it results from ingestion of well waters and vegetables high in nitrates ... /It was/ deduced that infants were prone to upset stomachs and achlorhydria. As result, stomach pH increased in alkalinity allowing nitrate-reducing organisms to enter and to reduce nitrates to nitrites. A gastric pH above 4 supports nitrate-reducing organisms ... Immature enzyme systems may also be of importance ... Fetal hemoglobin (hemoglobin F) is oxidized by nitrite to methemoglobin at rate twice as rapid as adult hemoglobin (hemoglobin A). Furthermore, enzymatic capacity of erythrocytes of newborn infants to reduce methemoglobin to hemoglobin appears less than that of adults. Difference is probably due to developmental deficiency in activity of DPNH-methemoglobin reductase (diphosphopyridine nucleotide). As opposed to adults, several clinical, physiologic and metabolic factors predispose infants to development of methemoglobinemia and acute nitrate poisoning. /Nitrate and nitrite/|For more Mechanism of Action (Complete) data for POTASSIUM NITRITE (6 total), please visit the HSDB record page.

Excerpt from ERG Guide 140 [Oxidizers]: Inhalation, ingestion or contact (skin, eyes) with vapors or substance may cause severe injury, burns or death. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may cause pollution. (ERG, 2016)

Excerpt from ERG Guide 140 [Oxidizers]: Ensure that medical personnel are aware of the material(s) involved and take precautions to protect themselves. Move victim to fresh air. Call 911 or emergency medical service. Give artificial respiration if victim is not breathing. Administer oxygen if breathing is difficult. Remove and isolate contaminated clothing and shoes. Contaminated clothing may be a fire risk when dry. In case of contact with substance, immediately flush skin or eyes with running water for at least 20 minutes. Keep victim calm and warm. (ERG, 2016)

Fresh air, rest. Artificial respiration may be needed. Refer for medical attention.

First rinse with plenty of water for at least 15 minutes, then remove contaminated clothes and rinse again.

First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention.

Maintain an open airway and assist ventilation if necessary. Administer supplemental oxygen. Treat hypotension with supine positioning, intravenous crystalloid fluids, and a low dose -pressor if needed. Monitor vital signs and ECG for 4 to 6 hours. Symptomatic methemoglobinemia may be treated with methylene blue. ... Administer activated charcoal. Gastric emptying is not necessary for small ingestions if activated charcoal can be given promptly . Hemodialysis and hemoperfusion are not effective. Severe methemoglobinemia in infants not responsive to methylene blue therapy may require exchange transfusion. /Nitrates and Nitrites/|Decontamination: Remove victim from exposure and administer supplemental oxygen if available. Remove contaminated clothing and wash with copious soap and water. Irrigate exposed eyes with water or saline. /Nitrates and NItrites/|Basic treatment: Establish a patent airway (oropharyngeal or nasopharyngeal airway, if needed). Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if necessary. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for shock and treat if necessary ... Anticipate seizures and treat as necessary ... For eye contamination, flush eyes immediately with water. Irrigate each eye continuously with 0.9% saline (NS) during transport ... Do not use emetics. For ingestion, rinse mouth and administer 5 ml/kg up to 200 d of water for dilution if the patient can swallow, has a strong gag reflex, and does not drool. Administer activated charcoal ... /Nitrates, nitrites, and related compounds/|Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious or is in severe respiratory distress. Monitor cardiac rhythm and treat arrhythmias if necessary. Start IV administration of D5W /SRP: "To keep open", minimal flow rate/. Use 0.9% saline (NS) or lactated Ringer's (LR) if signs of hypovolemia are present. For hypotension with signs of hypovolemia, administer fluid cautiously. If unresponsive to these measures, vasopressors may be helpful. Watch for signs of fluid overload ... Treat seizures with diazepam or lorazepam ... Administer 1% solution methylene blue if patient is symptomatic with severe hypoxia, cyanosis, and cardiac compromise not responding to oxygen. ... Use proparacaine hydrochloride to assist eye irrigation ... /Nitrates, nitrites, and related compounds/|For more Antidote and Emergency Treatment (Complete) data for POTASSIUM NITRITE (10 total), please visit the HSDB record page.

/HUMAN EXPOSURE STUDIES/ Symptoms of nitrite poisoning and MetHb formation after ingestion ranged from 0.4 to > 200 mg/kg bw, expressed as nitrite ion ... MetHb formation in different cases varied from 7.7 up to 79% ... /It was deduced that/ cyanosis occurred at MetHb concentration above 10%, and other symptoms at > 20% ... /Nitrite/[WHO; WHO Food Additives Series 35 (844): Nitrite. Available from, as of October 30, 2006: http://www.inchem.org/documents/jecfa/jecmono/v35je13.htm]|/SIGNS AND SYMPTOMS/ Symptomatology: 1. A prompt fall in blood pressure. 2. A roaring sound in the ears, a headache which is persistent and throbbing, with associated vertigo, a generalized tingling sensation, palpitations, and visual disturbances. 3. The skin is flushed and perspiring, later cold and cyanotic. 4. Nausea and vomiting. The ingestion of nitrites may also cause colic and diarrhea. 5. Syncope, esp when attempting to stand upright. 6. Methemoglobinemia, with attendant cyanosis and anoxia. 7. Hyperpnea; later dyspnea and slow breathing. 8. The pulse may be slow, dicrotic, and intermittent. 9. Incr intraocular tension and intracranial pressure. 10. Collapse and coma, followed by clonic convulsions. 11. Death due to circulatory collapse. /Nitrite/[Gosselin, R.E., R.P. Smith, H.C. Hodge. Clinical Toxicology of Commercial Products. 5th ed. Baltimore: Williams and Wilkins, 1984., p. III-317]|/SIGNS AND SYMPTOMS/ ... /Potassium nitrite/ is irritating to the eyes, the skin and the respiratory tract. The substance may cause effects on the cardiovascular system and blood, resulting in fall of blood pressure, formation of methemoglobin. Exposure may result in death. The effects may be delayed ...[IPCS, CEC; International Chemical Safety Card on Potassium nitrite. (April 2000). Available from, as of October 24, 2006: http://www.inchem.org/documents/icsc/icsc/eics1069.htm]|For more Human Toxicity Excerpts (Complete) data for POTASSIUM NITRITE (17 total), please visit the HSDB record page.

potassium nitrite

The substance can be absorbed into the body by inhalation of its aerosol and by ingestion.

Cough. Sore throat. Headache. Blue lips, fingernails and skin. Nausea. Dizziness. Confusion. Laboured breathing. Convulsions. Unconsciousness.

Redness.

Redness. Pain.

As a color fixative and preservative in meats; approximately 40% in lunch meat; approximately 40% in cured, smoked pork; approximately 10% in variety meat; approximately 10% in canned, cooked beef and pork and meat mixtures (1973)

Grade: CP; technical; reagent; FCC.|Nitrite of commerce usually contains about 85% potassium nitrite, remainder consisting chiefly of nitrate

Industrial gas manufacturing|Nitrous acid, potassium salt (1:1): ACTIVE|S - indicates a substance that is identified in a final Significant New Use Rule.|Food for babies less than 6 month of age should not contain added nitrites. /Nitrites/|Potassium nitrite has the pharmacological effects of the other nitrites.|MID /MEAT INSPECTION DIVISION (DEPARTMENT OF AGRICULTURE)/ LIMITATION: SOURCE OF NITRITE IN CURED PRODUCTS; 7 LB/100 GAL PICKLE; 3 1/2 OZ/100 LB MEAT (DRY CURE); 2 3/4 OZ/100 LB CHOPPED MEAT.

Method 418E: Devarda's Alloy Reduction Method. This method is recommended for oxidized nitrogen concn greater than 2 mg/l. In this technique, nitrate ion and nitrite ion are reduced to ammonia under hot alkaline conditions in the presence of a reducing agent, Devarda's alloy (an alloy of 50% copper, 45% aluminum and 5% zinc). The reduction is carried out in a kjeldahl distillation apparatus. Under hot alaline conditions, the ammonia formed distills and is trapped in a receiving flask containing boric acid. The ammonia can be determined either by direct nesslerization or acidimetrically. /A separate determination of nitrogen dioxide should be made and subtracted, otherwise the result is reported as "total oxidized nigrogen."/ The recovery of 200 to 400 ug nitrate ion-nitrogen from partially treated effluents was found to average 96% with a coefficient of variation of 7.7%. /Total oxidized nitrogen/|Method: EPA-NERL 300.0; Procedure: ion chromatography with conductivity detector; Analyte: nitrite; Matrix: drinking water, surface water, mixed domestic and industrial wastewaters, groundwater, reagent waters, solids (after extraction), leachates (when no acetic acid is used); Detection Limit: 0.004 mg/L. /Nitrite/|Method: EPA-OGWDW/TSC 300.1; Procedure: ion chromatography with conductivity detector; Analyte: nitrite; Matrix: reagent water, surface water, ground water, and finished drinking water; Detection Limit: 0.001 mg/L. /Nitrite/|Method: EPA-NERL 353.4; Procedure: automated gas segmented continuous flow colorimetric system; Analyte: nitrite; Matrix: estuarine and coastal waters; Detection Limit: not provided. /Nitrite/|For more Analytic Laboratory Methods (Complete) data for POTASSIUM NITRITE (17 total), please visit the HSDB record page.

Food additives|Food Additives -> COLOUR_RETENTION_AGENT; PRESERVATIVE; -> JECFA Functional Classes

Food Additives -> COLOUR_RETENTION_AGENT; PRESERVATIVE;