Chemical Safety Data Sheet MSDS / SDS
Pyridinium dichromate
Revision Date:2026-04-26Revision Number:1
Product identifier
- Product name: Pyridinium dichromate
- CBnumber: CB4390259
- CAS: 20039-37-6
- EINECS Number: 243-478-8
- Synonyms: PDC,PYRIDINIUM DICHROMATE
Relevant identified uses of the substance or mixture and uses advised against
- Relevant identified uses: For R&D use only. Not for medicinal, household or other use.
- Uses advised against: none
Company Identification
- Company: Chemicalbook
- Address: Building 1, Huihuang International, Shangdi 10th Street, Haidian District, Beijing
- Telephone: 010-86108875
GHS Label elements, including precautionary statements
-
Symbol(GHS)
- Signal wordDanger
P305+P351+P338 IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.
P303+P361+P353 IF ON SKIN (or hair): Remove/Take off Immediately all contaminated clothing. Rinse SKIN with water/shower.
P280 Wear protective gloves/protective clothing/eye protection/face protection.
P260 Do not breathe dust/fume/gas/mist/vapours/spray.
P210 Keep away from heat/sparks/open flames/hot surfaces. — No smoking.
Hazard statements
H410 Very toxic to aquatic life with long lasting effects
H317 May cause an allergic skin reaction
H314 Causes severe skin burns and eye damage
H272 May intensify fire; oxidizer
H228 Flammable solid
Substance
- Product name: Pyridinium dichromate
- Synonyms: PDC,PYRIDINIUM DICHROMATE
- CAS: 20039-37-6
- EC number: 243-478-8
- MF: C5H7Cr2NO7
- MW: 297.1
4.1 Description of first-aid measures
General adviceFirst aiders need to protect themselves. Show this material safety data sheet to the doctor in attendance.
If inhaled
After inhalation: fresh air. Call in physician.
In case of skin contact
In case of skin contact: Take off immediately all contaminated clothing. Rinse skin with water/ shower. Call a physician immediately.
In case of eye contact
After eye contact: rinse out with plenty of water. Immediately call in ophthalmologist.
Remove contact lenses.
If swallowed
Remove contact lenses.
After swallowing: make victim drink water (two glasses at most), avoid vomiting (risk of perforation). Call a physician immediately. Do not attempt to neutralise.
4.2 Most important symptoms and effects, both acute and delayed
The most important known symptoms and effects are described in the labelling (see section 2) and/or in section 11
4.3 Indication of any immediate medical attention and special treatment needed
No data available
4.4 Notes to physician
No data available
5.1 Extinguishing media
Suitable extinguishing mediaWater Foam Carbon dioxide (CO2) Dry powder
Unsuitable extinguishing media
For this substance/mixture no limitations of extinguishing agents are given.
5.2 Special hazards arising from the substance or mixture
Carbon oxides
Nitrogen oxides (NOx)
Chromium oxides
Combustible.
Development of hazardous combustion gases or vapours possible in the event of fire.
Nitrogen oxides (NOx)
Chromium oxides
Combustible.
Development of hazardous combustion gases or vapours possible in the event of fire.
5.3 Advice for firefighters
Stay in danger area only with self-contained breathing apparatus. Prevent skin contact by keeping a safe distance or by wearing suitable protective clothing.
Suppress (knock down) gases/vapors/mists with a water spray jet. Prevent fire extinguishing water from contaminating surface water or the ground water system.
Suppress (knock down) gases/vapors/mists with a water spray jet. Prevent fire extinguishing water from contaminating surface water or the ground water system.
NFPA 704
2
0
1
OX
| HEALTH | 2 | Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury (e.g. diethyl ether, ammonium phosphate, iodine) | |
| FIRE | 0 | Materials that will not burn under typical fire conditions, including intrinsically noncombustible materials such as concrete, stone, and sand. Materials that will not burn in air when exposed to a temperature of 820 °C (1,500 °F) for a period of 5 minutes.(e.g. Carbon tetrachloride) | |
| REACT | 1 | Normally stable, but can become unstable at elevated temperatures and pressures (e.g. propene) | |
| SPEC. HAZ. | OX |
6.1 Personal precautions, protective equipment and emergency procedures
Advice for non-emergency personnel: Avoid generation and inhalation of dusts in all circumstances. Avoid substance contact. Ensure adequate ventilation. Keep away from heat and sources of ignition. Evacuate the danger area, observe emergency procedures, consult an expert.
For personal protection see section 8.
For personal protection see section 8.
6.2 Environmental precautions
Do not let product enter drains. Risk of explosion.
6.3 Methods and materials for containment and cleaning up
Cover drains. Collect, bind, and pump off spills. Observe possible material restrictions (see sections 7 and 10). Take up carefully. Dispose of properly. Clean up affected area.
Avoid generation of dusts.
Avoid generation of dusts.
6.4 Reference to other sections
For disposal see section 13.
7.1 Precautions for safe handling
Advice on safe handlingWork under hood. Do not inhale substance/mixture.
Advice on protection against fire and explosion
Keep away from open flames, hot surfaces and sources of ignition.Take precautionary measures against static discharge.
Hygiene measures
Immediately change contaminated clothing. Apply preventive skin protection. Wash hands and face after working with substance.
For precautions see section 2.2.
For precautions see section 2.2.
7.2 Conditions for safe storage, including any incompatibilities
Storage conditionsKeep locked up or in an area accessible only to qualified or authorized persons. Tightly closed and away from sources of ignition and heat. Observe national regulations.
Handle and store under inert gas. Hygroscopic.
Storage class
Handle and store under inert gas. Hygroscopic.
Storage class (TRGS 510): 4.1A: Other explosive hazardous materials
8.1 Control parameters
Ingredients with workplace control parameters| ['Component', 'CAS-No.', 'Value', 'Control\nparameters', 'Basis'] | ['pyridinium\ndichromate', '20039-37-\n6', 'PC-TWA', '0.05 mg/m3', 'Occupational exposure limits for\nhazardous agents in the\nworkplace - Chemical\nhazardous agents.'] | ['', 'Remarks', 'G1 - Carcinogenic to humans\nSensitizing', None, None] |
|---|
8.2 Exposure controls
Appropriate engineering controlsImmediately change contaminated clothing. Apply preventive skin protection. Wash hands and face after working with substance.
Personal protective equipment
Eye/face protection
Use equipment for eye protection tested and approved under appropriate government standards such as NIOSH (US) or EN 166(EU). Tightly fitting safety goggles
Skin protection
This recommendation applies only to the product stated in the safety data sheet, supplied by us and for the designated use. When dissolving in or mixing with other substances and under conditions deviating from those stated in EN 16523-1 please contact the supplier of CE-approved gloves (e.g. KCL GmbH, D-36124 Eichenzell,
Internet: www.kcl.de).
Full contact
Material: Nitrile rubber
Minimum layer thickness: 0.11 mm
Break through time: 480 min
Material tested:KCL 741 L
Splash contact
Material: Nitrile rubber
Minimum layer thickness: 0.11 mm
Break through time: 480 min
Material tested:KCL 741 L
Internet: www.kcl.de).
Full contact
Material: Nitrile rubber
Minimum layer thickness: 0.11 mm
Break through time: 480 min
Material tested:KCL 741 L
Splash contact
Material: Nitrile rubber
Minimum layer thickness: 0.11 mm
Break through time: 480 min
Material tested:KCL 741 L
Body Protection
Flame retardant antistatic protective clothing.
Respiratory protection
required when dusts are generated.
Our recommendations on filtering respiratory protection are based on the following standards: DIN EN 143, DIN 14387 and other accompanying standards relating to the used respiratory protection system.
Our recommendations on filtering respiratory protection are based on the following standards: DIN EN 143, DIN 14387 and other accompanying standards relating to the used respiratory protection system.
Control of environmental exposure
Do not let product enter drains. Risk of explosion.
Information on basic physicochemical properties
- a) Physical statecrystalline
- b) Colororange, yellow
- c) OdorNo data available
- d) Melting point/freezing pointMelting point/range: 152 - 153 °C - lit.
- e) Initial boiling point and boiling rangeNo data available
- f) Flammability (solid, gas)1. - Flammability (solids)
The substance or mixture is a flammable solid with the category - g) Upper/lower flammability or explosive limitsNo data available
- h) Flash pointNot applicable
- i) Autoignition temperatureNo data available
- j) Decomposition temperatureca. 177 - 298 °C
Decomposes on heating. - k) pHNo data available
- l) ViscosityViscosity, kinematic: No data available
Viscosity, dynamic: No data available - m) Water solubility943 g/l at 20 °C - OECD Test Guideline 105- completely soluble
- n) Partition coefficient n-octanol/waterlog Pow: < -3.7 at 20 °C - Bioaccumulation is not expected.
- o) Vapor pressure0Pa at 25℃
- p) Density1.71[at 20℃]
- Relative density1.71 at 20 °C - OECD Test Guideline 109
- r) Particle characteristicsNo data available
- s) Explosive propertiesNo data available
- t) Oxidizing propertiesNo data available
- Solubilitysoluble in DMSO
9.2 Other safety information
Burning rate7.1 mm/s
10.1 Chemical stability
The product is chemically stable under standard ambient conditions (room temperature) .
10.2 Possibility of hazardous reactions
No data available
10.3 Conditions to avoid
no information available
10.4 Incompatible materials
Organic materials, Powdered metals
10.5 Hazardous decomposition products
In the event of fire: see section 5
11.1 Information on toxicological effects
Acute toxicityOral: No data available
Inhalation: No data available
Dermal: No data available
Skin corrosion/irritation
Inhalation: No data available
Dermal: No data available
Skin - In vitro study
Result: Corrosive after 1 to 4 hours of exposure (OECD Test Guideline 431)
Remarks: (Regulation (EC) No 1272/2008, Annex VI)
Serious eye damage/eye irritation
Result: Corrosive after 1 to 4 hours of exposure (OECD Test Guideline 431)
Remarks: (Regulation (EC) No 1272/2008, Annex VI)
Classified based on available data. For more details, see section 2
Respiratory or skin sensitization
Classified based on available data. For more details, see section 2
Germ cell mutagenicity
Classified based on available data. For more details, see section 2
Test Type: Ames test
Test system: S. typhimurium
Metabolic activation: with and without metabolic activation
Method: OECD Test Guideline 471
Result: Positive results were obtained in some in vitro tests.
Carcinogenicity
Test Type: Ames test
Test system: S. typhimurium
Metabolic activation: with and without metabolic activation
Method: OECD Test Guideline 471
Result: Positive results were obtained in some in vitro tests.
May cause cancer by inhalation.
Reproductive toxicity
Classified based on available data. For more details, see section 2
Classified based on available data. For more details, see section 2
Specific target organ toxicity - single exposure
Classified based on available data. For more details, see section 2
Classified based on available data. For more details, see section 2
Specific target organ toxicity - repeated exposure
Classified based on available data. For more details, see section 2
Aspiration hazard
Classified based on available data. For more details, see section 2
11.2 Additional Information
To the best of our knowledge, the chemical, physical, and toxicological properties have not been thoroughly investigated.
Chromium(VI) is highly toxic. It is absorbed via both the lungs and the gastrointestinal tract. Being strong oxidisers, chromates/ bichromates can cause burns and ulcerations on the skin and mucous membranes and also irritations in the upper respiratory tract. Poorly healing ulcers occur after wound contact. In predisposed persons the substance rapidly leads to sensitisation and allergic reactions of the respiratory tract (risk of pneumonia!) and damage to nasal mucous membranes (under given circumstances perforation of the septum). After swallowing severe symptoms in the gastrointestinal tract such as bloody diarrhoea, vomiting (aspiration pneumonia!), spasms, circulatory collapse, unconsciousness, formation of methaemoglobin. Absorption may result in hepatic and renal damage. Inhalable chromium(VI) compounds gave clear evidence to be carcinogenic in animal experiments. Lethal dose (man): 0.5g. Antidotes: chelating agents such as EDTA,
DMPS (Demaval®)
This substance should be handled with particular care.
Chromium(VI) is highly toxic. It is absorbed via both the lungs and the gastrointestinal tract. Being strong oxidisers, chromates/ bichromates can cause burns and ulcerations on the skin and mucous membranes and also irritations in the upper respiratory tract. Poorly healing ulcers occur after wound contact. In predisposed persons the substance rapidly leads to sensitisation and allergic reactions of the respiratory tract (risk of pneumonia!) and damage to nasal mucous membranes (under given circumstances perforation of the septum). After swallowing severe symptoms in the gastrointestinal tract such as bloody diarrhoea, vomiting (aspiration pneumonia!), spasms, circulatory collapse, unconsciousness, formation of methaemoglobin. Absorption may result in hepatic and renal damage. Inhalable chromium(VI) compounds gave clear evidence to be carcinogenic in animal experiments. Lethal dose (man): 0.5g. Antidotes: chelating agents such as EDTA,
DMPS (Demaval®)
This substance should be handled with particular care.
12.1 Toxicity
Toxicity to daphnia static test EC50 - Daphnia magna (Water flea) - 0.91 mg/l - 48 h and other aquatic (OECD Test Guideline 202) invertebrates
Toxicity to algae static test ErC50 - Pseudokirchneriella subcapitata (algae) - 1.05 mg/l - 72 h (OECD Test Guideline 201)
Toxicity to algae static test ErC50 - Pseudokirchneriella subcapitata (algae) - 1.05 mg/l - 72 h (OECD Test Guideline 201)
12.2 Persistence and degradability
Biodegradability aerobic - Exposure time 28 d
Result: 4.7 % - Not biodegradable (OECD Test Guideline 301E)
Result: 4.7 % - Not biodegradable (OECD Test Guideline 301E)
12.3 Bioaccumulative potential
No data available
12.4 Mobility in soil
No data available
12.5 Results of PBT and vPvB assessment
PBT/vPvB assessment not available as chemical safety assessment not required/not conducted
12.6 Endocrine disrupting properties
No data available
12.7 Other adverse effects
Discharge into the environment must be avoided.
13.1 Waste treatment methods
Product
Offer surplus and non-recyclable solutions to a licensed disposal company.
Offer surplus and non-recyclable solutions to a licensed disposal company.
14.1 UN number
ADR/RID: 3180
IMDG: 3180
IATA-DGR: 3180
IMDG: 3180
IATA-DGR: 3180
14.2 UN proper shipping name
ADR/RID: FLAMMABLE SOLID, CORROSIVE, INORGANIC, N.O.S. (pyridinium dichromate)
IMDG: FLAMMABLE SOLID, CORROSIVE, INORGANIC, N.O.S. (pyridinium dichromate)
IATA-DGR: Flammable solid, corrosive, inorganic, n.o.s. (pyridinium dichromate)
IMDG: FLAMMABLE SOLID, CORROSIVE, INORGANIC, N.O.S. (pyridinium dichromate)
IATA-DGR: Flammable solid, corrosive, inorganic, n.o.s. (pyridinium dichromate)
14.3 Transport hazard class(es)
ADR/RID: 4.1 (8)
IMDG: 4.1 (8)
IATA-DGR: 4.1 (8)
IMDG: 4.1 (8)
IATA-DGR: 4.1 (8)
14.4 Packaging group
ADR/RID: II
IMDG: II
IATA-DGR: II
IMDG: II
IATA-DGR: II
14.5 Environmental hazards
ADR/RID: yes
IMDG Marine pollutant: yes
IATA-DGR: no
IMDG Marine pollutant: yes
IATA-DGR: no
14.6 Special precautions for user
Based on chemical properties, choose appropriate tools and conditions of transport.
Transporting tools shall be equipped with appropriate and sufficient firefighting equipment and emergency leaking installations. If transporting by road, please go along the specified route.
Transporting tools shall be equipped with appropriate and sufficient firefighting equipment and emergency leaking installations. If transporting by road, please go along the specified route.
14.7 Incompatible materials
Organic materials, Powdered metals
15.1 Safety, health and environmental regulations/legislation specific for the substance or mixture
National regulatory information
Law on the Prevention and Control of Occupational Diseases
Regulations on Occupational Labor Protection in the at workplaces where Toxic
Substances Are Used
Catalogue of Highly Toxic Chemicals : Listed
Other regulations
Please pay attention on the waste treatment should also comply with local regulations requirement.
Law on the Prevention and Control of Occupational Diseases
Regulations on Occupational Labor Protection in the at workplaces where Toxic
Substances Are Used
Catalogue of Highly Toxic Chemicals : Listed
Other regulations
Please pay attention on the waste treatment should also comply with local regulations requirement.
Abbreviations and acronyms
CAS: Chemical Abstracts Service
TWA: Time-Weighted Average
STEL: Short-Term Exposure Limit
LD50: Lethal Dose 50%
LC50: Lethal Concentration 50%
EC50: Effective Concentration 50%
PEL: Permissible Exposure Limit
TLV: Threshold Limit Value
IMDG: International Maritime Dangerous Goods Code
IATA: International Air Transport Association
ADR: European Agreement concerning the International Carriage of Dangerous Goods by Road
DOT: US Department of Transportation
NFPA: National Fire Protection Association
NIOSH: National Institute for Occupational Safety and Health
OSHA: Occupational Safety and Health Administration
TWA: Time-Weighted Average
STEL: Short-Term Exposure Limit
LD50: Lethal Dose 50%
LC50: Lethal Concentration 50%
EC50: Effective Concentration 50%
PEL: Permissible Exposure Limit
TLV: Threshold Limit Value
IMDG: International Maritime Dangerous Goods Code
IATA: International Air Transport Association
ADR: European Agreement concerning the International Carriage of Dangerous Goods by Road
DOT: US Department of Transportation
NFPA: National Fire Protection Association
NIOSH: National Institute for Occupational Safety and Health
OSHA: Occupational Safety and Health Administration
Disclaimer:
The information in this MSDS is only applicable to the specified product, unless otherwise specified, it is not applicable to the mixture of this product and other substances. This MSDS only provides information on the safety of the product for those who have received the appropriate professional training for the user of the product. Users of this MSDS must make independent judgments on the applicability of this SDS. The authors of this MSDS will not be held responsible for any harm caused by the use of this MSDS.