2,3-Butanediol

90.12

90.12

208-173-6

249246

DTXSID8041321

Nearly colorless, crystalline solid or liquid

29053980

40.5

-0.9

Colorless to pale yellow Viscous Liquid

1.0033 g/cm³ @ Temp: 20 °C

7.6 °C

182 °C

185 °F

1.435

H2O: soluble

Store below +30°C.

<1 hPa (20 °C)

3.1 (Air = 1)

Oral-Rat LD50: 5462  mg/kg

Combustible in case of open flame, high temperature and strong oxidant; burning emits irritating smoke

3.1-11.4%(V)

Odorless

Sweet taste

Henry's Law constant= 2.88X10-8 atm-cu m/mol at 25 °C (est)

pKa = 14.9 at 25 °C; Kb = 0.33 at 25 °C, aqueous HCl

Hygroscopic|Occurs in 3 isomeric forms: meso- or erythro-, D(-)-threo-, and L(+)-threo-isomers|1 ppm = 3.68 mg/cu m and 1 mg/L = 272 ppm at 25 °C, 760 mmHg /Butandiols/|For more Other Experimental Properties (Complete) data for 2,3-Butanediol (7 total), please visit the HSDB record page.|Hygroscopic crystals from dry diisopropyl ether. MP: 34.4 °C; BP: 181.7 °C at 742 mm Hg, 89 °C at 16 mm Hg; Density: 0.9939 at 25 °C/4 °C; Index of refraction: 1.4324 at 35 °C/D; Moderatelt soluble in diisopropyl ether /meso-2,3-butylene glycol (erythro-2,3-butylene glycol)/|MP: 19.7 °C; BP: 179-180 °C at 745 mm Hg, 77.5-78 °C at 10 mm Hg; Density: 0.9869 at 25 °C/4 °C; Index of refraction: 1.4315 at 25 °C/D; Optical Rotation: -13.0 deg at 25 °C/D (neat) /D(-)-threo-2,3-butylene glycol/|BP: 179-182 °C at 745 mm Hg; Density: 0.9872 at 25 °C; Index of refraction: 1.4306 at 25 °C/D /L(+)-threo-2,3-butylene glycol/|Hydroxyl radical reaction rate constant= 2.36X10-11 cu cm/molecule-sec at 25 °C (est)

756 °F (402 °C)

-2461 kJ/mol at 20 °C

NONH for all modes of transport

1

24/25

EK0532000

Warehouse ventilated, low temperature and dry

Stable. Combustible. Incompatible with strong oxidizing agents, acid anhydrides, acid chlorides, chloroformates, reducing agents.

P264, P280, P305+P351+P338, P33, P313

H319

SRP: 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 air, soil or water; effects on animal, aquatic and plant life; and conformance with environmental and public health regulations. If it is possible or reasonable use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination.|Product: This combustible material may be burned in a chemical incinerator equipped with an afterburner and scrubber. Offer surplus and non-recyclable solutions to a licensed disposal company; Contaminated packaging: Dispose of as unused product.

Incompatible materials: Acid chlorides, acid anhydrides, oxidizing agents, chloroformates, reducing agents, zinc.|Incompatible with oxidizing materials.

Not Classified|Warning|H227: Combustible liquid [Warning Flammable liquids]|P210, P280, P370+P378, P403+P235, and P501

Eye/face protection: Safety glasses with side-shields conforming to EN166. Use equipment for eye protection tested and approved under appropriate government standards such as NIOSH (US) or EN 166(EU).|Skin protection: Handle with gloves.|Body Protection: Impervious clothing. The type of protective equipment must be selected according to the concentration and amount of the dangerous substance at the specific workplace.|Respiratory protection: Where risk assessment shows air-purifying respirators are appropriate use a full-face respirator with multipurpose combination (US) or type ABEK (EN 14387) respirator cartridges as a backup to engineering controls. If the respirator is the sole means of protection, use a full-face supplied air respirator. Use respirators and components tested and approved under appropriate government standards such as NIOSH (US) or CEN (EU).

Flammable when exposed to heat or flame.

Suitable extinguishing media: Use water spray, alcohol-resistant foam, dry chemical or carbon dioxide.|Advice for firefighters: Wear self-contained breathing apparatus for firefighting if necessary.|Use water spray to cool unopened containers.|To fight fire, use alcohol foam, carbon dioxide, dry chemical.

ACCIDENTAL RELEASE MEASURES: Personal precautions, protective equipment and emergency procedures: Avoid breathing vapors, mist or gas. Remove all sources of ignition. Beware of vapors accumulating to form explosive concentrations. Vapors can accumulate in low areas. Environmental precautions: Prevent further leakage or spillage if safe to do so. Do not let product enter drains. Methods and materials for containment and cleaning up: Contain spillage, and then collect with an electrically protected vacuum cleaner or by wet-brushing and place in container for disposal according to local regulations. Keep in suitable, closed containers for disposal.

ACCIDENTAL RELEASE MEASURES: Personal precautions, protective equipment and emergency procedures: Avoid breathing vapors, mist or gas. Remove all sources of ignition. Beware of vapors accumulating to form explosive concentrations. Vapors can accumulate in low areas. Environmental precautions: Prevent further leakage or spillage if safe to do so. Do not let product enter drains.|Precautions for safe handling: Avoid inhalation of vapor or mist. Keep away from sources of ignition - No smoking. Take measures to prevent the build up of electrostatic charge.|Appropriate engineering controls: Handle in accordance with good industrial hygiene and safety practice. Wash hands before breaks and at the end of workday.|Gloves must be inspected prior to use. Use proper glove removal technique (without touching glove's outer surface) to avoid skin contact with this product. Dispose of contaminated gloves after use in accordance with applicable laws and good laboratory practices. Wash and dry hands.

| 1 - Materials that, under emergency conditions, can cause significant irritation.| 1 - Materials that must be preheated before ignition can occur. Materials require considerable preheating, under all ambient temperature conditions, before ignition and combustion can occur.| 0 - Materials that in themselves are normally stable, even under fire conditions.

2,3-Butanediol was qualitatively identified as a component of garden waste volatiles collected from headspace gas in three waste collection trucks in Denmark(1). An unspecified isomer of butanediol was qualitatively identified as a volatile component at 1 of 5 hazardous waste sites(2). 2,3-Butanediol was detected in 3 of 7 samples of scrape tire pyrolysis at 5, 64 and 250 mg/kg scrap tire(3).

practically nontoxic

IDENTIFICATION AND USE: 2,3-Butanediol is nearly colorless, crystalline solid or liquid. 2,3-Butanediol is used as a crosslinking agent for naphthalene-1,5-diisocyanate in the production of specific hard-rubber products. Derivatives of 2,3-butanediol are important as intermediates in the pharmaceutical industry. 2,3-Butanediols have some interest as humectants and in the synthesis of polymers and plasticizers. HUMAN STUDIES: For erythrocytes a solution of 30% 2,3-butanediol showed relatively low toxicity. Hemolysis was only 2% after 5 hr, but increased to 6% after 21 hr and reached 60% after 46 hr. ANIMAL STUDIES: Effects of 2,3-butanediol on the central nervous system (CNS) were investigated by using the analysis of EEG (electroencephalogram) spectral powers recorded at the frontal cortex in rats. It was found that 2,3-butanediol treatment led to increase in EEG spectral powers by oral and intravenous administrations at relatively low doses. From these findings it can be concluded that 2,3-butanediol has a potent CNS depressant effect. 2,3-Butanediol was not embryotoxic when examined in cultured 10-day rat embryo. 2,3-Butanediol has a negative regulatory effect on rats innate immunity response.

Erythrocytes were stored at 4 degrees C in solutions of phosphate-buffered saline containing 2,3-butanediol and 4% (w/w) trehalose, sucrose, sorbitol, or mannitol. The 2,3-butanediol contained 96.7% (w/w) racemic mixture of the levo and dextro isomers and only 3.1% (w/w) of the meso isomer (2,3-butanediol 97% dl). The concentrations of 2,3-butanediol were 30 and 35% (w/w). A solution of 30% 2,3-butanediol showed relatively low toxicity. Hemolysis was only 2% after 5 hr, but increased to 6% after 21 hr and reached 60% after 46 hr. Adding 4% (w/w) of one of the above compounds drastically decreased the toxicity. The two most efficient were the sugars trehalose and sucrose. With 30% 2,3-butanediol and 4% of any of the four compounds, hemolysis was about 0.6% after 2 days of storage. Furthermore, with trehalose or sucrose, hemolysis remained below 3% for 1 month. With sorbitol or mannitol, hemolysis slowly increased to 2% after 7 days and then increased rapidly. Even with 35% 2,3-butanediol, solutions containing trehalose or sucrose showed low toxicity. Hemolysis was also measured after redilution to buffered solution without 2,3-butanediol and without the additive, to mimic perfusion of organs with cryoprotectants and washing. Minima of hemolysis were observed after a few days of storage. The present solutions also have high glass-forming tendencies. They could be of great interest for organ vitrification.|... A 16 hr pretreatment with either 2-butanone (2.1 mL/kg, orally) or 2,3-butanediol (2.12 mL/kg, orally) markedly enhanced the hepatotoxic response to CCl4 (0.1 mL/kg, ip), as measured by serum glutamic pyruvic transaminase activity and hepatic triglyceride content. In vivo, limited formation of 3-hydroxy-2-butanone occurred after this dose of 2,3-butanediol.

LD50 Mouse oral 5462 mg/kg|LD50 Mouse oral 9.0 mL/kg

2,3-Butanediol is a volatile constituent of sweet corn(1), fermented soybean curds(2), whole and ground grains(3), and rotten mussels(4). 2,3-Butanediol is produced in the fermentation of many fruits and grains(5). 2,3-Butanediol is found in the fruit of sweet pepper plants (Capsicum annuum)(6).

2,3-Butanediol's production and use as a solvent for dyes, in resins, as an intermediate, and as a blending agent(1) may result in its release to the environment through various waste streams(SRC).

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 1(SRC), determined from a structure estimation method(2), indicates that 2,3-butanediol is expected to have very high mobility in soil(SRC). Volatilization of 2,3-butanediol from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 2.9X10-8 atm-cu m/mole(SRC), based upon its vapor pressure, 0.24 mm Hg(3), and assigned value for water solubility of 1X10+6 mg/L (miscible)(4). 2,3-Butanediol is not expected to volatilize from dry soil surfaces(SRC) based upon a its vapor pressure(3). Using anaerobic test conditions, 75-100% biodegradation was reported(5), suggesting that biodegradation may be an important enviornmental fate process in soil under anoxic conditions(src).|AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 1(SRC), determined from a structure estimation method(2), indicates that 2,3-butanediol is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is not expected(3) based upon an estimated Henry's Law constant of 2.9X10-8 atm-cu m/mole(SRC), derived from its vapor pressure, 0.18 mm Hg(4), and assigned value for water solubility of 1X10+6 mg/L (miscible)(5). 2,3-Butanediol is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(3). According to a classification scheme(6), an estimated BCF of 3(SRC), from its log Kow of -0.92(7) and a regression-derived equation(2), suggests the potential for bioconcentration in aquatic organisms is low. Using anaerobic test conditions, 75-100% biodegradation was reported(8), suggesting that biodegradation may be an important enviornmental fate process in soil and water under anoxic conditions.|ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 2,3-butanediol, which has a vapor pressure of 0.24 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase 2,3-butanediol is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC); the half-life for this reaction in air is estimated to be 16 hours(SRC), calculated from its reported rate constant of 2.36X10-11 cu cm/molecule-sec at 25 °C(3). 2,3-Butanediol does not contain chromophores that absorb at wavelengths >290 nm(4) and, therefore, is not expected to be susceptible to direct photolysis by sunlight(SRC).

The rate constant for the vapor-phase reaction of 2,3-butanediol with photochemically-produced hydroxyl radicals has been reported as 2.36X10-11 cu cm/molecule-sec at 25 °C(1). This corresponds to an atmospheric half-life of about 16 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(2). 2,3-butanediol is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(3). 2,3-Butanediol does not contain chromophores that absorb at wavelengths >290 nm(3) and, therefore, is not expected to be susceptible to direct photolysis by sunlight(SRC).

An estimated BCF of 3 was calculated in fish for 2,3-butanediol(SRC), using a log Kow of -0.92(1) and a regression-derived equation(2). According to a classification scheme(3), this BCF suggests the potential for bioconcentration in aquatic organisms is low.

Using a structure estimation method based on molecular connectivity indices(1), the Koc of 2,3-butanediol can be estimated to be 1(SRC). According to a classification scheme(2), this estimated Koc value suggests that 2,3-butanediol is expected to have very high mobility in soil(SRC).

The Henry's Law constant for 2,3-butanediol is estimated as 2.9X10-8 atm-cu m/mole(SRC) derived from its vapor pressure, 0.24 mm Hg(1), and assigned value for water solubility of 1X10+6 mg/L (miscible)(2). This Henry's Law constant indicates that 2,3-butanediol is expected to be essentially nonvolatile from water and moist soil surfaces(3). 2,3-Butanediol is not expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure(1).

2,3-Butanediol is a volatile constituent of sweet corn with concentrations >5,000 ppb in canned cream, canned kernel, and frozen kernel and >3,000 ppb in fresh kernel corn(1). 2,3-Butanediol and meso-2,3-butanediol were detected as volatile constituents of microwave oven-produced popcorn with concentrations of 800 ppb and 1200 ppb, respectively(2). It was detected as a volatile constituent in two different brands of rice cakes with concentrations of 62 ppb and 38 ppb(3). 2,3-Butanediol was detected among volatile components in two of three samples of commercial fermented soybean curds with concentrations of 244.3 ppb and 333.5 ppb(4) and was detected among volatile components of whole and ground grains (sorghum)(5). 2,3-Butanediol was detected as a volatile constituent in rotten mussels collected from the Oarai coast in Ibaraki, Japan on July 31, 1985 with a concentration of 14.2 ppm(6).|2,3-Butanediol was detected in muskmelon (Cucumis melo cv Athena) fruit at 0.47 ppm, it was not detected in muskmelon essence, samples were collected in Florida(1). 2,3-Butanediol was detected in pink guava fruit (Psidium guajava L), it was not detected in guava essence, samples were collected in Florida(2). Balsamic vinegars, aged 0-25 years, collected from Modena and Reggio Emilia, Italy, contained 2,3-butanediol at 110-1561 mg/kg(3). The concentration of 2,3-butanediol in white wines from Muscat Lefko (Vitis vinifera) grapes from the Islands of Samos was reported as 130-2986 mg/L(4). 2,3-Butanediol was detected in red wines (Cabernet Sauvignon, Campbell Early, Shiraz, Cabernet Sauvignon/Merlot) from France, Korea, Australia and California(5). In wine samples collected from Basilicata and Campania, Italy, 2,3-butanediol was detected at 385.1-725.4 and 297.9-479.5 mg/L, respectively(6). 2,3-Butanediol was identified, not qualified, in Manchego-type cheese from Madrid, Spain(7).

NIOSH (NOES Survey 1981-1983) has statistically estimated that 44 workers (32 of these are female) were potentially exposed to 2,3-butanediol in the US(1). Occupational exposure to 2,3-butanediol may occur through inhalation and dermal contact with this compound at workplaces where 2,3-butanediol is produced or used(SRC). Monitoring data indicate that the general population may be exposed to 2,3-butanediol mostly through ingestion of food products containing 2,3-butanediol(SRC).

In a controlled experiment 15 (79%) of 19 severely alcoholic men but only 1 of 22 controls had a serum concentration of greater than or equal to 5 umol/l 2,3-butanediol after ingestion of distilled spirits.

2-Butanol, 3-hydroxy-2-butanone, and 2,3-butanediol were identified as metabolies in the serum of guinea pigs injected ip with methyl ethyl ketone.|... Glucuronides of 2,3-butanediol /were found/ in the urine of rabbits equivalent to about 20% of the dose given.|In a controlled experiment 15 (79%) of 19 severely alcoholic men but only 1 of 22 controls had a serum concentration of greater than or equal to 5 umol/L 2,3-butanediol after ingestion of distilled spirits. Another diol, 1,2-propanediol, was found in a concentration of greater than or equal to 5 umol/L in all patients' specimens after drinking; but it was also present in lower concentrations in the reference specimens of most of the patients. These data are consistent with the experimental evidence that ethanol can be metabolized in rats to produce 2,3-butanediol and with the epidemiological hypothesis that severely alcoholic men metabolize ethanol by a different pathway than do control subjects.|Understanding the capacity of Paenibacillus polymyxa DSM 365 to tolerate increasing concentrations of 2,3-butanediol (2,3-BD) is critical to engineering a 2,3-BD-overproducing strain. Hence, we investigated the response of P. polymyxa to high 2,3-BD concentrations. In fed-batch cultures (6-L bioreactor) 2,3-BD was accumulated to a maximum concentration of 47 g/L despite the presence of residual 13 g/L glucose in the medium. Concomitantly, accumulation of acetoin, the precursor of 2,3-BD increased after maximum 2,3-BD concentration was reached, suggesting that 2,3-BD was reconverted to acetoin after the concentration tolerance threshold of 2,3-BD was exceeded. Cultures of P. polymyxa were then challenged with levo-2,3-BD (20, 40 and 60 g/L) at 0h in a glucose medium, and a concentration dependent growth inhibition response to levo-2,3-BD was observed. The growth of P. polymyxa was completely inhibited by 60 g/L levo-2,3-BD. Furthermore, P. polymyxa was challenged with incremental 2,3-BD concentrations (20, 40 and 60 g/L at 12, 24 and 36 hr, respectively) to mimic 2,3-BD accumulation during fermentation. Interestingly, 2,3-BD was reconverted to acetoin when its concentration reached 60 g/L, possibly to alleviate 2,3-BD toxicity. Collectively, our findings indicate that 2,3-BD-mediated toxicity is a major metabolic impediment to 2,3-BD overproduction, thus, making it an important metabolic engineering target towards rational design of a 2,3-BD-overproducing strain.|The metabolism of diacetyl (2,3-butanedione), acetoin (3-hydroxy-2-butanone), and 2,3-butanediol, which are metabolites of acetaldehyde, was quantitatively investigated using rat liver homogenate, liver perfusion, and in vivo experiments. Diacetyl and acetoin were reduced to 2,3-butanediol in these experiments, but acetoin and 2,3-butanediol were scarcely oxidized to diacetyl, indicating that the reduction reaction to 2,3-butanediol from diacetyl occurs actively in rat liver. The formation of acetoin from diacetyl required either NADH or NADPH as a reductant, while the reduction of acetoin to 2,3-butanediol required NADH. Acetoin and 2,3-butanediol were more readily accumulated than diacetyl in brain tissue.

...The clearance rate for ... 2,3-butanediol was independent of dose for the two doses used (0.4 and 0.8 g/kg) and ... the half-life ... /was/ 3.45 hr ... .

/SRP:/ Immediate first aid: Ensure that adequate decontamination has been carried out. If patient is not breathing, start artificial respiration, preferably with a demand-valve resuscitator, bag-valve-mask device, or pocket mask, as trained. Perform CPR as necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on left side (head-down position, if possible) to maintain an open airway and prevent aspiration. Keep patient quiet and maintain normal body temperature. Obtain medical attention. /Higher alcohols (>3 carbons) and related compounds/|/SRP:/ 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 ... . Monitor for pulmonary edema and treat if necessary ... . Anticipate seizures and treat if 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 mL of water for dilution if the patient can swallow, has a strong gag reflex, and does not drool. Administer activated charcoal ... . /Higher alcohols (>3 carbons) and related compounds/|/SRP:/ Advanced Treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in severe respiratory distress. Positive-pressure ventilation techniques, with a bag-valve-mask device, may be beneficial. Consider drug therapy for pulmonary edema ... . Monitor cardiac rhythm and treat arrhythmias as 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. Consider vasopressors if patient is hypotensive with a normal fluid volume. Watch for signs of fluid overload ... . Monitor for signs of hypoglycemia (decreased LOC, tachycardia, pallor, dilated pupils, diaphoresis, and/or dextrose strip or glucometer readings below 50 mg) and administer 50% dextrose if necessary ... . Treat seizures with diazepam or lorazepam ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Higher alcohols (>3 carbons) and related compounds/

/ALTERNATIVE and IN VITRO TESTS/ Erythrocytes were stored at 4 degrees C in solutions of phosphate-buffered saline containing 2,3-butanediol and 4% (w/w) trehalose, sucrose, sorbitol, or mannitol. The 2,3-butanediol contained 96.7% (w/w) racemic mixture of the levo and dextro isomers and only 3.1% (w/w) of the meso isomer (2,3-butanediol 97% dl). The concentrations of 2,3-butanediol were 30 and 35% (w/w). A solution of 30% 2,3-butanediol showed relatively low toxicity. Hemolysis was only 2% after 5 hr, but increased to 6% after 21 hr and reached 60% after 46 hr. Adding 4% (w/w) of one of the above compounds drastically decreased the toxicity. The two most efficient were the sugars trehalose and sucrose. With 30% 2,3-butanediol and 4% of any of the four compounds, hemolysis was about 0.6% after 2 days of storage. Furthermore, with trehalose or sucrose, hemolysis remained below 3% for 1 month. With sorbitol or mannitol, hemolysis slowly increased to 2% after 7 days and then increased rapidly. Even with 35% 2,3-butanediol, solutions containing trehalose or sucrose showed low toxicity. Hemolysis was also measured after redilution to buffered solution without 2,3-butanediol and without the additive, to mimic perfusion of organs with cryoprotectants and washing. Minima of hemolysis were observed after a few days of storage. The present solutions also have high glass-forming tendencies. They could be of great interest for organ vitrification.

2,3-butanediol

Grade: 99%|The commercial product is usually either the meso- or the D(-)-form.

Plastic material and resin manufacturing|2,3-Butanediol: ACTIVE

A liquid chromatography coupled with electrospray tandem mass spectrometry method was developed for the analysis of ethylene glycol, diethylene glycol, triethylene glycol, 1,4-butanediol, 1,2-butanediol, 2,3-butanediol, 1,2-propanediol and 1,3-propanediol, in serum after a Schotten-Baumann derivatization by benzoyl chloride. Usual validation parameters were tested: linearity, repeatability and intermediate precision, limits of detection and quantification, carry over and ion suppression. Limits of detection were between 0.18 and 1.1 mg/L, and limits of quantification were between 0.4 and 2.3 mg/L. Separation of isomers was possible either chromatographically or by selecting specific multiple reaction monitoring transitions. This method could be a useful tool in case of suspected intoxication with antifreeze agents, solvents, dietary supplements or some medical drug compounds.|... Butanediol mixture is analyzed best by GC (polyethylene glycol as stationary phase).

Gas chromatographic determination of 2,3-butanediol isomers in urine.

Food additives -> Flavoring Agents

Flavoring Agents