88-99-3 structure, C8H6O4

phthalic acid





Basic Info

Phthalic acid is an aromatic dicarboxylic acid, with formula C6H4(CO2H)2. It is an isomer of isophthalic acid and terephthalic acid. Although phthalic acid is of modest commercial importance, the closely related derivative phthalic anhydride is a commodity chemical produced on a large scale.

Molecular Weight
Exact Mass

1,2-Benzenedicarboxylic acid

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Appearance & Physical State
white crystals
1.451 g/cm3
Boiling Point
378.274ºC at 760 mmHg
Melting Point
Flash Point
Water Solubility
7 g/L (25 ºC)
Stable. Combustible. Incompatible with strong oxidizing agents.
Storage Condition
Store in a tightly closed container. Store in a cool, dry, well-ventilated area away from incompatible substances.

Safety Info

Safety Statements
WGK Germany
Risk Statements
HS Code
Caution Statement
P261; P305 + P351 + P338
Hazard Codes
Hazard Declaration
Caution Statement


SDS 1.0
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According to Globally Harmonized System of Classification and Labelling of Chemicals (GHS) - Sixth revised edition

Version: 1.0

Creation Date: Aug 12, 2017

Revision Date: Aug 12, 2017


1.1 GHS Product identifier

Product name phthalic acid

1.2 Other means of identification

Product number -
Other names 1,2-Benzenedicarboxylic acid

1.3 Recommended use of the chemical and restrictions on use

Identified uses For industry use only. Metabolite
Uses advised against no data available

1.4 Supplier's details

Company MOLBASE (Shanghai) Biotechnology Co., Ltd.
Address Floor 4 & 5, Building 12, No. 1001 North Qinzhou Road,
Xuhui District, Shanghai, China
Telephone +86(21)64956998
Fax +86(21)54365166

1.5 Emergency phone number

Emergency phone number +86-400-6021-666
Service hours Monday to Friday, 9am-5pm (Standard time zone: UTC/GMT +8 hours).

2.Hazard identification

2.1 Classification of the substance or mixture

Serious eye damage, Category 1

2.2 GHS label elements, including precautionary statements

Signal word


Hazard statement(s)

H318 Causes serious eye damage

Precautionary statement(s)

P280 Wear protective gloves/protective clothing/eye protection/face protection.


P305+P351+P338 IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing.

P310 Immediately call a POISON CENTER/doctor/…





2.3 Other hazards which do not result in classification


3.Composition/information on ingredients

3.1 Substances

Chemical name Common names and synonyms CAS number EC number Concentration
phthalic acid phthalic acid 88-99-3 none 100%

4.First-aid measures

4.1 Description of necessary first-aid measures

General advice

Consult a physician. Show this safety data sheet to the doctor in attendance.

If inhaled

Fresh air, rest.

In case of skin contact

Rinse and then wash skin with water and soap.

In case of eye contact

Rinse with plenty of water for several minutes (remove contact lenses if easily possible).

If swallowed

Rinse mouth.

4.2 Most important symptoms/effects, acute and delayed

SYMPTOMS: Symptoms of exposure to this compound may include irritation of the skin, eyes, mucous membranes, and respiratory passages. In high concentrations, it can cause narcosis. ACUTE/CHRONIC HAZARDS: This compound is an irritant of the skin, eyes, mucous membranes, and respiratory tract. It is narcotic in high concentrations. When heated, it decomposes to a compound which in the form of dust is an explosion hazard. Hazardous decomposition products include carbon oxides.

4.3 Indication of immediate medical attention and special treatment needed, if necessary

Inhalation Exposure: Fresh air, rest. Skin Exposure: Remove contaminated clothes. Rinse and then wash skin with water and soap. Eye exposure: First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then take to a doctor. Ingestion: Rinse mouth.

5.Fire-fighting measures

5.1 Extinguishing media

Suitable extinguishing media

Powder, water spray, foam, carbon dioxide.

5.2 Specific hazards arising from the chemical

This chemical is combustible.

5.3 Special protective actions for fire-fighters

Wear self-contained breathing apparatus for firefighting if necessary.

6.Accidental release measures

6.1 Personal precautions, protective equipment and emergency procedures

Use personal protective equipment. Avoid dust formation. Avoid breathing vapours, mist or gas. Ensure adequate ventilation. Evacuate personnel to safe areas. Avoid breathing dust. For personal protection see section 8.

6.2 Environmental precautions

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.

6.3 Methods and materials for containment and cleaning up

Sweep spilled substance into containers; if appropriate, moisten first to prevent dusting (extra personal protection: P1 filter respirator for inert particles).

7.Handling and storage

7.1 Precautions for safe handling

Avoid contact with skin and eyes. Avoid formation of dust and aerosols. Avoid exposure - obtain special instructions before use.Provide appropriate exhaust ventilation at places where dust is formed. For precautions see section 2.2.

7.2 Conditions for safe storage, including any incompatibilities

Store in cool place. Keep container tightly closed in a dry and well-ventilated place.

8.Exposure controls/personal protection

8.1 Control parameters

Occupational Exposure limit values

no data available

Biological limit values

no data available

8.2 Appropriate engineering controls

Handle in accordance with good industrial hygiene and safety practice. Wash hands before breaks and at the end of workday.

8.3 Individual protection measures, such as personal protective equipment (PPE)

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

Wear impervious clothing. The type of protective equipment must be selected according to the concentration and amount of the dangerous substance at the specific workplace. Handle with gloves. 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. The selected protective gloves have to satisfy the specifications of EU Directive 89/686/EEC and the standard EN 374 derived from it.

Respiratory protection

Wear dust mask when handling large quantities.

Thermal hazards

no data available

9.Physical and chemical properties

Physical state white crystals
Colour Colorless crystals
Odour no data available
Melting point/ freezing point 210°C(lit.)
Boiling point or initial boiling point and boiling range 155°C/0.5mmHg(lit.)
Flammability Combustible.
Lower and upper explosion limit / flammability limit no data available
Flash point 88°C(lit.)
Auto-ignition temperature no data available
Decomposition temperature 191°C
pH no data available
Kinematic viscosity no data available
Solubility In water:7 g/L (25 ºC)
Partition coefficient n-octanol/water (log value) no data available
Vapour pressure 6.36X10-7 mm Hg at 25°C
Density and/or relative density 1.451 g/cm3
Relative vapour density 5.73 (AIR= 1)
Particle characteristics no data available

10.Stability and reactivity

10.1 Reactivity

no data available

10.2 Chemical stability

Stable under recommended storage conditions.

10.3 Possibility of hazardous reactions

Combustible when heated.Dust explosion possible if in powder or granular form, mixed with air.PHTHALIC ACID is a carboxylic acid. This chemical is sensitive to exposure to extreme heat. This compound reacts violently with nitric acid. It is incompatible with sodium nitrite. It is also incompatible with oxidizers. .

10.4 Conditions to avoid

no data available

10.5 Incompatible materials

Mixtures of sodium nitrite and phthalic acid or phthalic anhydride explode violently on heating. A nitrite ester may have been produced.

10.6 Hazardous decomposition products

When heated to decomposition it emits acrid smoke and irritating fumes.

11.Toxicological information

Acute toxicity

  • Oral: LD50 Mouse oral 2,530 mg/kg
  • Inhalation: no data available
  • Dermal: no data available

Skin corrosion/irritation

no data available

Serious eye damage/irritation

no data available

Respiratory or skin sensitization

no data available

Germ cell mutagenicity

no data available


no data available

Reproductive toxicity

no data available

STOT-single exposure

no data available

STOT-repeated exposure

no data available

Aspiration hazard

no data available

12.Ecological information

12.1 Toxicity

  • Toxicity to fish: no data available
  • Toxicity to daphnia and other aquatic invertebrates: no data available
  • Toxicity to algae: no data available
  • Toxicity to microorganisms: no data available

12.2 Persistence and degradability

AEROBIC: After an acclimation of an activated sludge inoculum for 24 days, 95% of phthalate was consumed in a respiratory test(1). Phthalic acid completely degraded in 2 days in a screening test using a soil inoculum(2). Over 99% primary degradation was obtained in the semicontinuous activated sludge test of the Soap and Detergent Association(3). Degradation by some microorganisms is impeded when phthalic acid is adsorbed on particles such as aluminum oxide(4). Five day BOD studies have shown 78% degradation of phthalic acid(5). A biodegradation rate constant for phthalic acid of 1.56/day was measured in river water corresponding to a half life of 10.7 hrs(6). A half life of 2 days was measured in sludge amended soil(7). Phthalic acid rapidly degraded in Chalmers soil (1.96% organic carbon, pH 6.0); 100% decomposition, as determined by C02 evolution, was obtained after 53 days(8). In a river die-away test using water from the Mississippi River at St Louis, phthalic acid completely disappeared in 2.5 and 5 wks at concns of 12.5 and 50 mg/L, respectively(9). In another river die-away test using Missouri River water and carboxyl-labeled 14C-phthalic acid, 66-92% mineralization was obtained in 32 days(10). Bacteria that grew aerobically on phthalic acid were found in sediment and water from the estuary of the Mississippi River indicating the potential for phthalic acid biodegradation in the marine environment(11).

12.3 Bioaccumulative potential

An estimated BCF of 3 was calculated for phthalic acid(SRC), using a log Kow of 0.73(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(SRC).

12.4 Mobility in soil

The Koc values were determined for an acidic forest soil (Podzol, 4.85% organic carbon, pH 2.8), an agricultural soil (Alfisol, 1.25% organic carbon, pH 6.7) and a sublimnic soil (sediment from Lake Constance, Germany, 1.58% organic carbon, pH 7.1) as 31, 2 and 2, respectively(1). According to a classification scheme(2), these Koc values suggest that phthalic acid is expected to have very high mobility in soil. Phthalic acid adsorbs strongly to aluminum and iron oxides via a surface ligand exchange reaction(3). Adsorptivity is sensitive to pH; for aluminum oxide the fraction absorbed is >0.8 below pH 6 and falls below 0.1 above pH 7.5(3).

12.5 Other adverse effects

no data available

13.Disposal considerations

13.1 Disposal methods


The material can be disposed of by removal to a licensed chemical destruction plant or by controlled incineration with flue gas scrubbing. Do not contaminate water, foodstuffs, feed or seed by storage or disposal. Do not discharge to sewer systems.

Contaminated packaging

Containers can be triply rinsed (or equivalent) and offered for recycling or reconditioning. Alternatively, the packaging can be punctured to make it unusable for other purposes and then be disposed of in a sanitary landfill. Controlled incineration with flue gas scrubbing is possible for combustible packaging materials.

14.Transport information

14.1 UN Number

ADR/RID: Not dangerous goods. IMDG: Not dangerous goods. IATA: Not dangerous goods.

14.2 UN Proper Shipping Name

ADR/RID: unknown
IMDG: unknown
IATA: unknown

14.3 Transport hazard class(es)

ADR/RID: Not dangerous goods. IMDG: Not dangerous goods. IATA: Not dangerous goods.

14.4 Packing group, if applicable

ADR/RID: Not dangerous goods. IMDG: Not dangerous goods. IATA: Not dangerous goods.

14.5 Environmental hazards

ADR/RID: no IMDG: no IATA: no

14.6 Special precautions for user

no data available

14.7 Transport in bulk according to Annex II of MARPOL 73/78 and the IBC Code

no data available

15.Regulatory information

15.1 Safety, health and environmental regulations specific for the product in question

Chemical name Common names and synonyms CAS number EC number
phthalic acid phthalic acid 88-99-3 none
European Inventory of Existing Commercial Chemical Substances (EINECS) Listed.
EC Inventory Listed.
United States Toxic Substances Control Act (TSCA) Inventory Listed.
China Catalog of Hazardous chemicals 2015 Not Listed.
New Zealand Inventory of Chemicals (NZIoC) Listed.
Philippines Inventory of Chemicals and Chemical Substances (PICCS) Listed.
Vietnam National Chemical Inventory Listed.
Chinese Chemical Inventory of Existing Chemical Substances (China IECSC) Listed.

16.Other information

Information on revision

Creation Date Aug 12, 2017
Revision Date Aug 12, 2017

Abbreviations and acronyms

  • CAS: Chemical Abstracts Service
  • ADR: European Agreement concerning the International Carriage of Dangerous Goods by Road
  • RID: Regulation concerning the International Carriage of Dangerous Goods by Rail
  • IMDG: International Maritime Dangerous Goods
  • IATA: International Air Transportation Association
  • TWA: Time Weighted Average
  • STEL: Short term exposure limit
  • LC50: Lethal Concentration 50%
  • LD50: Lethal Dose 50%
  • EC50: Effective Concentration 50%


  • IPCS - The International Chemical Safety Cards (ICSC), website: http://www.ilo.org/dyn/icsc/showcard.home
  • HSDB - Hazardous Substances Data Bank, website: https://toxnet.nlm.nih.gov/newtoxnet/hsdb.htm
  • IARC - International Agency for Research on Cancer, website: http://www.iarc.fr/
  • eChemPortal - The Global Portal to Information on Chemical Substances by OECD, website: http://www.echemportal.org/echemportal/index?pageID=0&request_locale=en
  • CAMEO Chemicals, website: http://cameochemicals.noaa.gov/search/simple
  • ChemIDplus, website: http://chem.sis.nlm.nih.gov/chemidplus/chemidlite.jsp
  • ERG - Emergency Response Guidebook by U.S. Department of Transportation, website: http://www.phmsa.dot.gov/hazmat/library/erg
  • Germany GESTIS-database on hazard substance, website: http://www.dguv.de/ifa/gestis/gestis-stoffdatenbank/index-2.jsp
  • ECHA - European Chemicals Agency, website: https://echa.europa.eu/

Disclaimer: The above information is believed to be correct but does not purport to be all inclusive and shall be used only as a guide. The information in this document is based on the present state of our knowledge and is applicable to the product with regard to appropriate safety precautions. It does not represent any guarantee of the properties of the product. We as supplier shall not be held liable for any damage resulting from handling or from contact with the above product.
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Name: Phthalic acid p.a. Material Safety Data Sheet
Synonym: o-Benzenedicarboxylic acid; 1,2-benzenedicarboxylic acid; o-dicarboxybenzen
CAS: 88-99-3
Section 1 - Chemical Product   MSDS Name:Phthalic acid p.a. Material Safety Data Sheet
Synonym:o-Benzenedicarboxylic acid; 1,2-benzenedicarboxylic acid; o-dicarboxybenzen

CAS# Chemical Name content EINECS#
88-99-3 Phthalic acid ca. 100 201-873-2
Hazard Symbols: XI
Risk Phrases: 36/37/38

Irritating to eyes, respiratory system and skin.
Potential Health Effects
Causes eye irritation.
May cause skin irritation. May cause dermatitis.
Causes gastrointestinal irritation with nausea, vomiting and diarrhea.
Causes respiratory tract irritation.
Prolonged or repeated skin contact may cause dermatitis.

  Eyes: Immediately flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid.
Get medical aid. Immediately flush skin with plenty of water for at least 15 minutes while removing contaminated clothing and shoes.
Wash clothing before reuse.
Never give anything by mouth to an unconscious person. Get medical aid immediately. Do NOT induce vomiting. If conscious and alert, rinse mouth and drink 2-4 cupfuls of milk or water.
Get medical aid immediately. Remove from exposure and move to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen.
Notes to Physician:

  General Information:
As in any fire, wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion.
Extinguishing Media:
For small fires, use dry chemical, carbon dioxide, water spray or alcohol-resistant foam. Use water spray, dry chemical, carbon dioxide, or appropriate foam.

  General Information: Use proper personal protective equipment as indicated in Section 8.
Vacuum or sweep up material and place into a suitable disposal container. Avoid generating dusty conditions. Provide ventilation.

Section 7 - HANDLING and STORAGE
Wash thoroughly after handling. Remove contaminated clothing and wash before reuse. Use with adequate ventilation. Minimize dust generation and accumulation. Avoid contact with eyes, skin, and clothing. Avoid ingestion and inhalation.
Store in a tightly closed container. Store in a cool, dry, well-ventilated area away from incompatible substances.

  Engineering Controls:
Facilities storing or utilizing this material should be equipped with an eyewash facility and a safety shower. Use adequate general or local exhaust ventilation to keep airborne concentrations below the permissible exposure limits.
Exposure Limits CAS# 88-99-3: Personal Protective Equipment Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166.
Wear appropriate protective gloves to prevent skin exposure.
Wear appropriate protective clothing to prevent skin exposure.
A respiratory protection program that meets OSHA's 29 CFR 1910.134 and ANSI Z88.2 requirements or European Standard EN 149 must be followed whenever workplace conditions warrant respirator use.

Physical State: Solid
Color: white
Odor: None reported.
pH: Not available.
Vapor Pressure: Not available.
Viscosity: Not available.
Boiling Point: Not available.
Freezing/Melting Point: 210 deg C
Autoignition Temperature: Not available.
Flash Point: Not applicable.
Explosion Limits, lower: Not available.
Explosion Limits, upper: Not available.
Decomposition Temperature: > 210 deg C
Solubility in water: Slightly soluble in water.
Specific Gravity/Density: Not available.
Molecular Formula: C6H4(COOH)2
Molecular Weight: 166.0396

  Chemical Stability:
Stable at room temperature in closed containers under normal storage and handling conditions.
Conditions to Avoid:
Incompatible materials, dust generation.
Incompatibilities with Other Materials:
Strong oxidizing materials.
Hazardous Decomposition Products:
Carbon monoxide, irritating and toxic fumes and gases, carbon dioxide.
Hazardous Polymerization: Has not been reported.

CAS# 88-99-3: TH9625000 LD50/LC50:
CAS# 88-99-3: Oral, mouse: LD50 = 2530 mg/kg.
Phthalic acid - Not listed by ACGIH, IARC, or NTP.
See actual entry in RTECS for complete information.

Not available low potential to affect aquatic organisms, secondary waste treatment microorganisms and the germination of some plants.
It has a moderate potential to affect the germination and growth of some plants.

  Dispose of in a manner consistent with federal, state, and local regulations.

Not regulated as a hazardous material.
Not regulated as a hazardous material.
Not regulated as a hazardous material.

European/International Regulations
European Labeling in Accordance with EC Directives
Hazard Symbols: XI
Risk Phrases:
R 36/37/38 Irritating to eyes, respiratory system
and skin.
Safety Phrases:
S 26 In case of contact with eyes, rinse immediately
with plenty of water and seek medical advice.
S 37/39 Wear suitable gloves and eye/face
WGK (Water Danger/Protection)
CAS# 88-99-3: 0
CAS# 88-99-3 is listed on Canada's DSL List.
CAS# 88-99-3 is not listed on Canada's Ingredient Disclosure List.
CAS# 88-99-3 is listed on the TSCA inventory.



NMR Spectrum 1H NMR : 400 MHz in DMSO-d6
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IR Spectrum IR : nujol mull
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Mass Spectrum Mass spectrum (electron ionization)
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Raman Spectrum Raman : 4880 A,200 M,powder
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UV Spectrum UV/Visible spectrum
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Analysis Methods

Normal alkane RI, non-polar column, temperature ramp
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Column Shape
Active Phase(℃)
Retention index
Temperature Control
temperature ramp
30. m/0.32 mm/0.25 μm, Helium, 30. C @ 3. min, 4. K/min, 250. C @ 10. min
Escalona-Arranz, J.C.Perez-Roses, R.Jimenez, I.L.Rodriguez-Amado, J.Argota-Coello, H.Canizares-Lay, J.Morris-Quevedo, H.J.Sierra-Gonzales, G.Chemical constituents of Tamarindus indica L. leavesRev. Cubana Quim.2010, 22, 3, 65-71.
Lee's RI, non-polar column, temperature ramp
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Column Shape
Active Phase(℃)
Retention index
Temperature Control
temperature ramp
30. m/0.25 mm/0.25 μm, Helium, 50. C @ 1.5 min, 6. K/min, 310. C @ 10. min
Pedersen, D.U.Durant, J.L.Taghizadeh, K.Hemond, H.F.Lafleur, A.L.Cass, G.R.Human cell mutagenes in respirable airborne particles from the Northeastern United States. 2. Quantification of mutagenes and other organic compounds.Environ. Sci. Technol.2005, 39, 24, 9547-9560.

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