Citric Acid

1Identification

Name

Citric Acid

IUPAC name

2-hydroxypropane-1,2,3-tricarboxylic acid

CAS number

77-92-9

EC number

201-069-1

Molecular formula

C6H8O7

Molecular weight

192.12 g/mol

InChIKey

KRKNYBCHXYNGOX-UHFFFAOYSA-N

SMILES

C(C(=O)O)C(CC(=O)O)(C(=O)O)O

PubChem CID

311

Synonyms

citric acid, 2-hydroxypropane-1,2,3-tricarboxylic acid, Citric acid, anhydrous, Aciletten, Anhydrous citric acid, Citro, Citretten, Citric acid anhydrous, Chemfill, Hydrocerol A, 1,2,3-Propanetricarboxylic acid, 2-hydroxy-, 2-hydroxy-1,2,3-propanetricarboxylic acid, Kyselina citronova, 2-Hydroxytricarballylic acid

Recommended uses

• CIR ingredient: Citric Acid
  Cosmetic Ingredient Review (CIR)
• A Compound from citrus fruits that is an intermediate in the tricarboxylic acid (Krebs) cycle. It is used as an acidifying agent in foods, beverages, and pharmaceuticals. Citrate chelates calcium ions and prevents blood clotting. It is also used as an anticoagulant for stored whole blood and red cells and also for blood specimens. (Dorland, 28th ed) [ChemIDplus]
  Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
• For citric acid (USEPA/OPP Pesticide Code: 21801) ACTIVE products with label matches. /SRP: Registered for use in the U.S. but approved pesticide uses may change periodically and so federal, state and local authorities must be consulted for currently approved uses./
  Hazardous Substances Data Bank (HSDB)
• Flavoring and nutrient Other Binder Monomers Processing aids not otherwise specified Antioxidant pH regulating agent Cleaning agent Soil amendments (fertilizers) Catalyst Filler Not Known or Reasonably Ascertainable Preservative Intermediate Surface modifier
  EPA Chemical Data Reporting (CDR)
• Cleaning agent Preservative Corrosion inhibitor Not Known or Reasonably Ascertainable Catalyst Soil amendments (fertilizers) Anti-stain agent Chelating agent Anti-scaling agent Flavoring and nutrient Other Processing aids not otherwise specified pH regulating agent
  EPA Chemical Data Reporting (CDR)

Use categories: EPA Safer Chemical Functional Use Classes -> Antimicrobial Actives;Chelating Agents;Processing Aids and Additives · Safer Chemical Classes -> Green circle - The chemical has been verified to be of low concern · Food additives · Animal Drugs -> FDA Approved Animal Drug Products (Green Book) -> Active Ingredients

Description

• Citric acid appears as colorless, odorless crystals with an acid taste. Denser than water. (USCG, 1999)
  CAMEO Chemicals
• Citric acid is a tricarboxylic acid that is propane-1,2,3-tricarboxylic acid bearing a hydroxy substituent at position 2. It is an important metabolite in the pathway of all aerobic organisms. It has a role as a calcium chelator, an antimicrobial agent, a chelator, a food acidity regulator and a fundamental metabolite. It is a conjugate acid of a citrate anion and a citrate(1-).
  ChEBI
• A key intermediate in metabolism. It is an acid compound found in citrus fruits. The salts of citric acid (citrates) can be used as anticoagulants due to their calcium-chelating ability. Citric acid is one of the active ingredients in Phexxi, a non-hormonal contraceptive agent that was approved by the FDA on May 2020. It is also used in combination with magnesium oxide to form magnesium citrate, an osmotic laxative.
  DrugBank

2Hazard identification

Signal word

Warning

Pictograms

GHS07

Classification source

Regulation (EC) No 1272/2008 of the European Parliament and of the Council

Precautionary statements

Other reported classifications

4 classification records exist across sources. Differences usually reflect purity, physical form or impurities.

Health hazards

• Inhalation of dust irritates nose and throat. Contact with eyes causes irritation. (USCG, 1999)
  CAMEO Chemicals

Fire hazards

• Behavior in Fire: Melts and decomposes. The reaction is not hazardous. (USCG, 1999)
  CAMEO Chemicals
• Combustible. Finely dispersed particles form explosive mixtures in air.
  ILO-WHO International Chemical Safety Cards (ICSCs)

Hazards summary

• An irritant to the throat and eyes; [CAMEO] Concentrated solutions can cause severe eye damage and blindness; Animals fed 1.2% citric acid for 90 weeks showed no adverse effects except erosion of tooth enamel. [CHEMINFO]
  Haz-Map, Information on Hazardous Chemicals and Occupational Diseases

3Composition / information on ingredients

This page describes the pure substance. Commercial products may be solutions or mixtures. Check Section 3 of your supplier's SDS for concentrations and other ingredients.

4First-aid measures

• EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. If symptoms (such as redness or irritation) develop, immediately transport the victim to a hospital. SKIN: IMMEDIATELY flood affected skin with water while removing and isolating all contaminated clothing. Gently wash all affected skin areas thoroughly with soap and water.
  CAMEO Chemicals

Symptoms of exposure

• Cough. Shortness of breath. Sore throat.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• Redness.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• Redness. Pain.
  ILO-WHO International Chemical Safety Cards (ICSCs)

5Fire-fighting measures

• Extinguish with/ water, foam, dry chem, carbon dioxide.
  Hazardous Substances Data Bank (HSDB)

6Accidental release measures

Spill cleanup

• Personal protection: particulate filter respirator adapted to the airborne concentration of the substance. Sweep spilled substance into covered containers. If appropriate, moisten first to prevent dusting. Wash away remainder with plenty of water.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• Personal protection: particulate filter respirator adapted to the airborne concentration of the substance. Sweep spilled substance into covered containers. If appropriate, moisten first to prevent dusting. Wash away remainder with plenty of water.
  Hazardous Substances Data Bank (HSDB)

7Handling and storage

• Separated from strong oxidants, strong bases, metal nitrates and metals. Dry.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• Crystalline citric acid, anhydrous, can be stored in dry form without difficulty, although conditions of high humidity and elevated temperatures should be avoided to prevent caking. Storage should be in tight containers to prevent exposure to moist air. Several granulations are commercially available with the larger particle sizes having less tendency toward caking.
  Hazardous Substances Data Bank (HSDB)
• Temperature: ambient; Venting: open.
  Hazardous Substances Data Bank (HSDB)
• Containers: 230 lb Barrels, bags, kegs, boxes, cartons, fiber drums, bottles.
  Hazardous Substances Data Bank (HSDB)

8Exposure controls / personal protection

No occupational exposure limits found in our sources.

Personal protective equipment

• Dust mask; goggles or face shield; protective gloves (USCG, 1999)
  CAMEO Chemicals
• Use ventilation (not if powder).
  Hazardous Substances Data Bank (HSDB)
• Dust mask; goggles or face shield; protective gloves
  Hazardous Substances Data Bank (HSDB)

9Physical and chemical properties

10Stability and reactivity

Reactivity

• CITRIC ACID reacts with oxidizing agents, bases, reducing agents and metal nitrates (NTP, 1992). Reactions with metal nitrates are potentially explosive. Heating to the point of decomposition causes emission of acrid smoke and fumes [Lewis].
  CAMEO Chemicals
• The pure material is moisture sensitive (undergoes slow hydrolysis) Water soluble.
  CAMEO Chemicals

Incompatible materials and hazardous reactions

• Potentially explosive reaction with metal nitrates.
  Hazardous Substances Data Bank (HSDB)
• Reacts with oxidants and bases. Attacks metals.
  Hazardous Substances Data Bank (HSDB)

11Toxicological information

Short-term exposure effects

• The substance is irritating to the eyes, skin and respiratory tract.
  ILO-WHO International Chemical Safety Cards (ICSCs)

Long-term exposure effects

• The substance may have effects on the teeth. This may result in erosion.
  ILO-WHO International Chemical Safety Cards (ICSCs)

12Ecological information

Not available in the public sources we compile. Check Section 12 of the supplier's SDS.

13Disposal considerations

• SRP: Wastewater from contaminant suppression, cleaning of protective clothing/equipment, or contaminated sites should be contained and evaluated for subject chemical or decomposition product concentrations. Concentrations shall be lower than applicable environmental discharge or disposal criteria. Alternatively, pretreatment and/or discharge to a permitted wastewater treatment facility is acceptable only after review by the governing authority and assurance that "pass through" violations will not occur. Due consideration shall be given to remediation worker exposure (inhalation, dermal and ingestion) as well as fate during treatment, transfer and disposal.
  Hazardous Substances Data Bank (HSDB)
• Inject at base of incinerator equipped with afterburner. Flammable solvent may be added.
  Hazardous Substances Data Bank (HSDB)

14Transport information

Not available in the public sources we compile. Check Section 14 of the supplier's SDS.

How DOT hazard classes work →

15Regulatory information

• Unless specifically excluded, residues resulting from the use of the following substance as either an inert or an active ingredient in a pesticide chemical formulation, including antimicrobial pesticide chemicals, is exempted from the requirement of a tolerance under FFDCA section 408, if such use is in accordance with good agricultural or manufacturing practices. Citric acid is included on this list.
  Hazardous Substances Data Bank (HSDB)
• Section 4(g)(2)(A) of FIFRA requires the Agency to determine, after consideration of relevant data concerning an active ingredient whether products containing the active ingredient are eligible for reregistration. For products containing citric acid as an active ingredient the Agency has waived all generic data requirements except for those basic product identity and chemistry. These data were submitted and reviewed. In addition to these data, the Agency has considered the factors ... regarding citric acid's natural occurrence, common use as a food item, and the lack of reported adverse effects information.
  Hazardous Substances Data Bank (HSDB)
• Substance added directly to human food affirmed as generally recognized as safe (GRAS).
  Hazardous Substances Data Bank (HSDB)

Overview of SDS regulations (OSHA HazCom, WHMIS, REACH/CLP) →

16Other information

Compiled from PubChem CID 311 and the sources it aggregates (attributed inline). Data retrieved 2026-10-12. This summary describes the pure substance and is not a supplier SDS.