Welcome to our website!
Deutsche Español français italiano português 日本語 한국어 العربية русский bahasa Indonesia Tiếng Việt

Product Catalog

Rapid Product Index

Recommended Products

Friend Links

Your Location：Home>Product Center >> Pesticide API and intermediates >> Pyridine
  • Pyridine
Name:Pyridine
CAS No:110-86-1

PRODUCT DESCRIPTION

【Name】
Pyridine
【CAS Registry number】
110-86-1
【Synonyms】
Pyridine anhydrous
Azabenzene
Pyridin
Pyr
【EINECS(EC#)】
203-809-9
【Molecular Formula】
C5H5N (Products with the same molecular formula)
【Molecular Weight】
79.1
【Inchi】
InChI=1/C5H5N/c1-2-4-6-5-3-1/h1-5H
【InChIKey】
JUJWROOIHBZHMG-UHFFFAOYSA-N
【Canonical SMILES】
C1=CC=NC=C1
【MOL File】
110-86-1.mol

Chemical and Physical Properties

【Appearance】
Clear clean liquid with characteristic odour
【Density】
0.978
【Melting Point】
-42℃
【Boiling Point】
115-116℃
【Vapour】
23.8 mm Hg ( 25 °C)
【Refractive Index】
1.5085-1.5105
【Flash Point】
17℃
【Water】
Miscible
【Solubilities】
Miscible with water
【Color/Form】
Colorless to yellow liquid.
【Stability】
Stable. Flammable. Incompatible with strong oxidizing agents, strong acids.
【Storage temp】
Store at RT.
【Spectral properties】
Index of refraction: 1.50920 @ 20 deg C/D
MAX ABSORPTION (CYCLOHEXANE): 251 NM (LOG E= 3.1); 256 NM (LOG E= 3.1); 279 NM (LOG E= 2.0) SHOULDER; 284 NM (LOG E= 1.8) SHOULDER; 288 NM (LOG E= 1.4) SHOULDER
IR: 4840 (Coblentz Society Spectral Collection)
UV: 9 (Sadtler Research Laboratories Spectral Collection)
NMR: 96 (Varian Associates NMR Spectra Catalogue)
MASS: 62073 (NIST/EPA/MSDC Mass Spectral Database, 1990 version)
Intense mass spectral peaks: 52 m/z, 79 m/z
【Computed Properties】
Molecular Weight:79.0999 [g/mol]
Molecular Formula:C5H5N
XLogP3:0.7
H-Bond Donor:0
H-Bond Acceptor:1
Rotatable Bond Count:0
Exact Mass:79.042199
MonoIsotopic Mass:79.042199
Topological Polar Surface Area:12.9
Heavy Atom Count:6
Formal Charge:0
Complexity:30.9
Isotope Atom Count:0
Defined Atom Stereocenter Count:0
Undefined Atom Stereocenter Count:0
Defined Bond Stereocenter Count:0
Undefined Bond Stereocenter Count:0
Covalently-Bonded Unit Count:1
Feature 3D Acceptor Count:1
Feature 3D Ring Count:1
Effective Rotor Count:0
Conformer Sampling RMSD:0.4
CID Conformer Count:1

Safety and Handling

【Hazard Codes】
F:Flammable;Xn:Harmful;
【Risk Statements】
R11;R20/21/22
【Safety Statements 】
S26;S28
【HazardClass】
3
【Hazard Note】
Highly Flammable/Harmful
【Safety】

Hazard Codes of Pyridine (CAS NO.110-86-1): ToxicT,DangerousN,FlammableF,HarmfulXn 
Risk Statements: 11-20/21/22-39-23/24/25 
R11:Highly flammable. 
R20/21/22: Harmful by inhalation, in contact with skin and if swallowed. 
R39: Danger of very serious irreversible effects. 
R23/24/25: Toxic by inhalation, in contact with skin and if swallowed. 
Safety Statements: 36/37/39-38-45-61-26-28-24/25-22-16-7 
S36/37/39: Wear suitable protective clothing, gloves and eye/face protection. 
S38: In case of insufficient ventilation, wear suitable respiratory equipment. 
S45: In case of accident or if you feel unwell, seek medical advice immediately (show the label whenever possible.) 
S61: Avoid release to the environment. Refer to special instructions / safety data sheets. 
S26: In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. 
S28: After contact with skin, wash immediately with plenty of soap-suds. 
S24/25: Avoid contact with skin and eyes. 
S22: Do not breathe dust. 
S16: Keep away from sources of ignition. 
S7: Keep container tightly closed. 
RIDADR :UN 1282 3/PG 2
WGK Germany: 2
RTECS: UR8400000
F: 3-10 
Hazard Note: Highly Flammable/Harmful 
HazardClass: 3 
PackingGroup: II 
Irritates skin and eye. Can cause dizziness, headache, central nervous system depression, gastrointestinal upset, and liver and kidney damage. 
Severe explosion hazard in the form of vapor when exposed to flame or spark. 
When heated to decomposition it emits highly toxic fumes of NOx.
Currently, there is inadequate evidence that it's a possible carcinogenic agent  in humans, though there is limited evidence of carcinogenic effects on animals.

【PackingGroup 】
II
【Skin, Eye, and Respiratory Irritations】
Irritating to eyes, nose, and throat. May cause smarting of the skin ...
... Pyridine & its derivatives cause local irritation on contact with the skin, mucous membranes & cornea.
It is a mild skin and severe eye irritant.
【Cleanup Methods】
1. REMOVE ALL IGNITION SOURCES. 2. VENTILATE AREA OF SPILL OR LEAK. 3. FOR SMALL QUANTITIES, ABSORB ON PAPER TOWELS, EVAPORATE IN SAFE PLACE (SUCH AS FUME HOOD). ALLOW SUFFICIENT TIME FOR EVAPORATING VAPORS TO COMPLETELY CLEAR HOOD DUCTWORK. BURN PAPER IN SUITABLE LOCATION AWAY FROM COMBUSTIBLE MATERIAL. 3. LARGE QUANTITIES CAN BE COLLECTED & ATOMIZED IN SUITABLE COMBUSTION CHAMBER EQUIPPED WITH APPROPRIATE EFFLUENT GAS CLEANING DEVICE. PYRIDINE SHOULD NOT BE ALLOWED TO ENTER CONFINED SPACE, SUCH AS SEWER, BECAUSE OF POSSIBILITY OF EXPLOSION.
Biological treatment of wastewater for the removal of pyridine.
Removal of pyridine from waste gases by adsorption.
Eliminate all ignition sources. Stop or control the leak, if this can be done without undue risk. Use water spray to cool and disperse vapors, protect personnel, and dilute spills to form nonflammable mixtures. Control run-off and isolate discharged materials for proper disposal.
【Transport】
UN 1282
【Fire Fighting Procedures】
Use water spray, dry chemical, "alcohol resistant" foam, or carbon dioxide. Solid streams of water may be ineffective. Use water spray to keep fire-exposed containers cool.
If material is on fire or involved in fire: Do not extinguish fire unless flow can be stopped or safely confined. Use water in flooding quantities as fog. Solid streams may be ineffective. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. Use "alcohol" foam, carbon dioxide, or dry chemical.
【Fire Potential】
Pyridine is a flammable ... liquid.
Dangerous fire hazard when exposed to heat, flame, or oxidizers.
【Formulations/Preparations】
Grades: Technical at 20 deg C, 2 deg (meaning distillation range); Medicinal; CP; Spectrophotometric
【DOT Emergency Guidelines】
/GUIDE 129: FLAMMABLE LIQUIDS (POLAR/WATER-MISCIBLE/NOXIOUS)/ Fire or Explosion: HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames. Vapors may form explosive mixtures with air. Vapors may travel to source of ignition and flash back. Most vapors are heavier than air. They will spread along ground and collect in low confined areas (sewers, basements, tanks). Vapor explosion hazard indoors, outdoors or in sewers. Runoff to sewer may create fire or explosion hazard. Containers may explode when heated. Many liquids are lighter than water.
/GUIDE 129: FLAMMABLE LIQUIDS (POLAR/WATER-MISCIBLE/NOXIOUS)/ Health: May cause toxic effects if inhaled or absorbed through skin. Inhalation or contact with material may irritate or burn skin and eyes. Fire will produce irritating, corrosive and/or toxic gases. Vapors may cause dizziness or suffocation. Runoff from fire control or dilution water may cause pollution.
/GUIDE 129: FLAMMABLE LIQUIDS (POLAR/WATER-MISCIBLE/NOXIOUS)/ Public Safety: CALL Emergency Response Telephone Number ... . As an immediate precautionary measure, isolate spill or leak area for at least 50 meters (150 feet) in all directions. Keep unauthorized personnel away. Stay upwind. Keep out of low areas. Ventilate closed spaces before entering.
/GUIDE 129: FLAMMABLE LIQUIDS (POLAR/WATER-MISCIBLE/NOXIOUS)/ Protective Clothing: Wear positive pressure self-contained breathing apparatus (SCBA). Structural firefighters' protective clothing will only provide limited protection.
/GUIDE 129: FLAMMABLE LIQUIDS (POLAR/WATER-MISCIBLE/NOXIOUS)/ Evacuation: Large spill: Consider initial downwind evacuation for at least 300 meters (1000 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.
/GUIDE 129: FLAMMABLE LIQUIDS (POLAR/WATER-MISCIBLE/NOXIOUS)/ Fire: Caution: All these products have a very low flash point: Use of water spray when fighting fire may be inefficient. Small fires: Dry chemical, CO2, water spray or alcohol-resistant foam. Do not use dry chemical extinguishers to control fires involving nitromethane or nitroethane. Large fires: Water spray, fog or alcohol-resistant foam. Do not use straight streams. Move containers from fire area if you can do it without risk. Fire involving tanks or car/trailer loads: Fight fire from maximum distance or use unmanned hose holders or monitor nozzles. Cool containers with flooding quantities of water until well after fire is out. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks engulfed in fire. For massive fire, use unmanned hose holders or monitor nozzles; if this is impossible, withdraw from area and let fire burn.
/GUIDE 129: FLAMMABLE LIQUIDS (POLAR/WATER-MISCIBLE/NOXIOUS)/ Spill or Leak: ELIMINATE all ignition sources (no smoking, flares, sparks or flames in immediate area). All equipment used when handling the product must be grounded. Do not touch or walk through spilled material. Stop leak if you can do it without risk. Prevent entry into waterways, sewers, basements or confined areas. A vapor suppressing foam may be used to reduce vapors. Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers. Use clean non-sparking tools to collect absorbed material. Large spills: Dike far ahead of liquid spill for later disposal. Water spray may reduce vapor; but may not prevent ignition in closed spaces.
/GUIDE 129: FLAMMABLE LIQUIDS (POLAR/WATER-MISCIBLE/NOXIOUS)/ First Aid: 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. In case of contact with substance, immediately flush skin or eyes with running water for at least 20 minutes. Wash skin with soap and water. Keep victim warm and quiet. In case of burns, immediately cool affected skin for as long as possible with cold water. Do not remove clothing if adhering to skin. Effects of exposure (inhalation, ingestion or skin contact) to substance may be delayed. Ensure that medical personnel are aware of the material(s) involved and take precautions to protect themselves.
【Exposure Standards and Regulations】
Pyridine is a food additive permitted for direct addition to food for human consumption as a synthetic flavoring substance and adjuvant in accordance with the following conditions: a) they are used in the minimum quantity required to produce their intended effect, and otherwise in accordance with all the principles of good manufacturing practice, and 2) they consist of one or more of the following, used alone or in combination with flavoring substances and adjuvants generally recognized as safe in food, prior-sanctioned for such use, or regulated by an appropriate section in this part.
【Reactivities and Incompatibilities】
PYRIDINE REACTS VIOLENTLY WITH CHLOROSULFONIC ACID, CHROMIC ACID, MALEIC ANHYDRIDE, NITRIC ACID, FUMING SULFURIC ACID, PERCHROMATES, BETA-PROPIOLACTONE, SILVER PERCHLORATE, & SULFURIC ACID.
Incompatible with strong oxidizers.
... Contact with strong acids will cause violent spattering.
DANGEROUS ... WHEN EXPOSED TO HEAT, FLAME OR OXIDIZERS.
Reaction with bromine trifluoride gives solid which ignites when dry. Forms unstable complex with chromium trioxide. Reacts violently with liquid dinitrogen tetroxide. Incandesces on contact with fluorine.
Strong oxidizers, strong acids.
Reacts to form pyrophoric or explosive products with ... trifluoromethyl hypofluorite. Mixtures with formamide + iodine + sulfur trioxide are storage hazards, releasing carbon dioxide & sulfuric acid.
【Other Preventative Measures】
... HANDLING OF PYRIDINE SHOULD BE CONDUCTED IN WELL-VENTILATED CONDITIONS ... .
Open lights and other /ignition sources/ capable of igniting pyridine and its vapor should be excluded from areas where pyridine is exposed in the course of manipulation.
Employees should wash immediately when skin is wet or contaminated. Remove clothing immediately if wet or contaminated to avoid flammability hazard. Provide emergency showers and eyewash.
Employees who handle liquid pyridine or solutions containing pyridine should wash their hands thoroughly before eating, smoking, or using toilet facilities.
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. Build dikes to contain flow as necessary. Attempt to stop leak if without hazard. Use water spray to disperse vapors and dilute standing pools of liquid.
Personnel protection: Avoid breathing vapors. Keep upwind. Avoid bodily contact with the material. Do not handle broken packages unless wearing appropriate personal protective equipment.
If the use of respirators is necessary, the only respirators permitted are those that have been approved by the Mine Safety and Health Administration (formerly Mining Enforcement and Safety Administration) or by the National Institute for Occupational Safety and Health. In addition to respirator selection, a complete respiratory protection program should be instituted which includes regular training, maintenance, inspection, cleaning, and evaluation.
Clothing contaminated with liquid pyridine should be placed in closed containers for storage until it can be discarded or until provision is made for the removal of pyridine from the clothing. If the clothing is to be laundered or otherwise cleaned to remove the pyridine, the person performing the operation should be informed of pyridine's hazardous properties. Non-impervious clothing which becomes contaminated with liquid pyridine should be removed immediately and not reworn until the pyridine is removed from the clothing.
... PROCESS PLANT SHOULD, BY PREFERENCE, BE ENCLOSED AND FITTED WITH LOCAL EXHAUST VENTILATION. DEPENDING ON THE EXTENT OF POSSIBLE CONTACT, WORKERS SHOULD BE PROVIDED WITH PERSONAL PROTECTIVE EQUIPMENT.
Skin that becomes wet with liquid pyridine should be promptly washed or showered. Eating and smoking should not be permitted in areas where liquid pyridine is handled, processed, or stored.
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.
The worker should immediately wash the skin when it becomes contaminated.
Work clothing that becomes wet should be immediately removed due to its flammability hazard.
Eyewash fountains should be provided in areas where there is any possbility that workers could be exposed to the substance; this is irrespective of the recommendation involving the wearing of eye protection.
【Protective Equipment and Clothing】
WEAR SPECIAL PROTECTIVE CLOTHING AND POSITIVE PRESSURE SELF-CONTAINED BREATHING APPARATUS.
Employees should be provided with and required to use impervious clothing, gloves, face-shields (eight-inch minimum), and other appropriate protective clothing necessary to prevent skin contact with liquid pyridine or solutions containing pyridine, where skin contact may occur.
Depending on the extent of possible contact, workers should be provided with personal protective equipment. A charcoal gas mask canister respirator has been found to be effective against a 2% pyridine concentration at 30 l/min for 1 hr. Rubber and plastic gloves should not be relied upon to prevent skin contact because pyridine and many of its derivatives penetrate these materials ... . /Pyridine, homologues, and derivatives/
Wear appropriate personal protective clothing to prevent skin contact.
Wear appropriate eye protection to prevent eye contact.
Facilities for quickly drenching the body should be provided within the immediate work area for emergency use where there is a possibility of exposure. [Note: It is intended that these facilities provide a sufficient quantity or flow of water to quickly remove the substance from any body areas likely to be exposed. The actual determination of what constitutes an adequate quick drench facility depends on the specific circumstances. In certain instances, a deluge shower should be readily available, whereas in others, the availability of water from a sink or hose could be considered adequate.]
Recommendations for respirator selection. Max concn for use: 125 ppm. Respirator Class(es): Any supplied-air respirator operated in a continuous flow mode. Eye protection needed. Any powered, air-purifying respirator with organic vapor cartridge(s). Eye protection needed.
Recommendations for respirator selection. Max concn for use: 250 ppm. Respirator Class(es): Any chemical cartridge respirator with a full facepiece and organic vapor cartridge(s). Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted organic vapor canister. Any powered, air-purifying respirator with a tight-fitting facepiece and organic vapor cartridge(s). Eye protection needed. Any self-contained breathing apparatus with a full facepiece. Any supplied-air respirator with a full facepiece.
Recommendations for respirator selection. Max concn for use: 1000 ppm. Respirator Class(es): Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode.
Recommendations for respirator selection. Condition: Emergency or planned entry into unknown concn or IDLH conditions: Respirator Class(es): Any self-contained breathing apparatus that has a full facepiece and is operated in a pressure-demand or other positive pressure mode. Any supplied-air respirator that has a full face piece and is operated in pressure-demand or other positive pressure mode in combination with an auxiliary self-contained breathing apparatus operated in pressure-demand or other positive pressure mode.
Recommendations for respirator selection. Condition: Escape from suddenly occurring respiratory hazards: Respirator Class(es): Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted organic vapor canister. Any appropriate escape-type, self-contained breathing apparatus.
【Specification】

Degraded by bacteria to ammonia and carbon dioxide.

【Octanol/Water Partition Coefficient】
log Kow = 0.65
【Report】

Community Right-To-Know List. Reported in EPA TSCA Inventory. EPA Genetic Toxicology Program.
 

【Disposal Methods】
Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number U196, F005, and D038 must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.
A potential candidate for rotary kiln incineration at a temperature range of 820 to 1,600 deg C and residence times of seconds for liquids and gases, and hours for solids. A potential candidate for liquid injection incineration at a temperature range of 650 to 1,600 deg C and a residence time of 0.1 to 2 seconds. A potential candidate for fluidized bed incineration at a temperature range of 450 to 980 deg C and residence times of seconds for liquids and gases, and longer for solids.
The following wastewater treatment technologies have been investigated for Pyridine: Concentration process: Activated carbon.
Controlled incineration whereby nitrogen oxides are removed from the effluent gas by scrubber, catalytic or thermal devices. Recommendable method: Incineration. Not recommendable methods: Evaporation & landfill.
Photolysis: Treatment pyridine-containing effluents by uv-light irradiation is suggested. The photodegradation of pyridine by uv-light decreases in magnitude with increasing pH and is heavily inhibited in an alkaline medium (pH 10 to 12). Irradiation of pyridine water solutions with different pH values leads to production of intermediate photolytic products with mutually different light- absorption spectra. Photo-oxidation of pyridine and its primary degradation products occurs at the expense of the oxidant radicals that form during water photolysis. The presence of dissolved free oxygen adds intensity to the oxidative processes, thus increasing the yield of hydrogen peroxide. The latter's presence makes the photochemical breakdown of pyridine maximum effective and complete. In the process, the rate of pyridine photolysis increases, 3-3.5 times and its destruction, as well as of the products resulting from the photochemical reactions, is complete within 20-25 minutes of irradiation exposure, in the absence of FE(II) or FE(III) or their oxalate complexes. With the FE(II) or FE(III) oxalate complexes, the pyridine photolysis rate is much faster.
The limitations and feasibility of the land disposal of solid wastes containing organic solvents and refrigerants were investigated by evaluating the attenuation capacity of a hypothetical waste disposal site by numerical modeling. The basic theorem of this approach was that the land disposal of wastes would be environmentally acceptable if subsurface attenuation reduced groundwater concentrations of organic compounds to concentrations that were less than health based, water quality criteria. Computer simulations indicated that the predicted concentrations of 13 of 33 organic compounds in groundwater would be less than their health based criteria. Hence solid wastes containing these compounds could be safely disposed at the site. The attenuation capacity of the site was insufficient to reduce concentrations of 4 compounds to safe levels without limiting the amount of mass available to leach into groundwater. Threshold masses based on time dependent migration simulations were estimated for these compounds. Pyridine was one of 16 compounds that could not be safely landfilled without severe restrictions on the amounts disposed.
Pyridine is a waste chemical stream constituent which may be subjected to ultimate disposal by controlled incineration.
Spillage disposal: Wear butyl rubber gloves, laboratory coat and eye protection. Cover the spill with a 1:1:1 mixture by weight of sodium carbonate or calcium carbonate, clay cat litter (bentonite) and sand. Scoop into an appropriate labeled container for disposal by burning in a furnace equipped with an afterburner and scrubber.
Waste disposal: Compound should be burned. Dissolve in combustible solvent such as alcohol or benzene. Spray the solution into a furnace equipped with afterburner and scrubber.

Use and Manufacturing

【Use and Manufacturing】
Methods of Manufacturing

REACTION OF ACETALDEHYDE, AMMONIA, AND FORMALDEHYDE IN THE PRESENCE OF A CATALYST SUCH AS AN OXIDE OR A PHOSPHATE OF A TRI OR TETRAVALENT METAL AT 250-500 DEG C AND ATMOSPHERIC PRESSURE; NATURAL PYRIDINE IS DERIVED IN ISOLATED FORM FROM COKING OPERATIONS.
BY EXTRACTION FROM LOWER-BOILING FRACTIONS OF TAR DISTILLATES AFTER REMOVAL OF TAR ACIDS BY SULFURIC ACID & PURIFICATION BY DISTILLATION WITH LIME ... .
MOST COMMERCIAL PYRIDINE IS OBTAINED BY DISTILLATION FROM CRUDE COAL TAR ... . INCREASED DEMAND FOR HIGH-PURITY PYRIDINE HAS LED TO ... SYNTHESIZING IT FROM ACETYLENE, FORMALDEHYDE, HEMIMETHYLAL & AMMONIA.
Pyridine and pyridine derivatives are made from paraldehyde and aqueous ammonia, in the presence of a catalyst, at elevated temperatures.
Vapor phase reaction of acrolein with ammonia, in the presence of a dehydration catalyst, produces high yields of beta-picoline and pyridine in a ratio of approximately 2:1.
U.S. Exports

(1975) 3.41X10+9 GRAMS
(1970) 1.36X10+9 GRAMS
U.S. Imports

(1973) 4.5X10+6 GRAMS
(1970) 4.6X10+7 GRAMS
U.S. Production

(1970) 4.09X10+9 GRAMS (2 DEG C GRADE)
Consumption Patterns

APPROX 33% IS USED AS A SOLVENT IN DRUG MFR AND AS A REAGENT (INCL AS A SCAVENGER FOR ACIDS); 17-33% AS AN INT FOR ANTIHISTAMINES (INCL CHLOROPHENIRAMINE MALEATE) AND ANTI-INFECTIVES (INCL CETYLPYRIDINIUM CHLORIDE); 8-17% AS AN INT FOR PIPERIDINE; 8-17% AS AN INT FOR WATERPROOFING AGENTS IN THE TEXTILE INDUST; AND 8-17% IN MISC APPLICATIONS (1970)
(1975) 6.81X10+9 G (SECONDARY CONSUMPTION EST)

Biomedical Effects and Toxicity

【Pharmacological Action】
Vapor irritates eyes and nose. Liquid irritates skin and is absorbed through the skin. Overexposure causes nausea, headache, nervous symptoms, increased urinary frequency.
【Biomedical Effects and Toxicity】
Pyridine is absorbed from the gastrointestinal tract, through the skin, and by inhalation. Part of the absorbed pyridine is excreted in the urine unchanged and a smaller portion is methylated at the N position.
Elimination of pyridine is biphasic in nature, the 1st phase being more prolonged for pyridine and beta-picoline than for alpha- or gamma-picoline.
Uptake by tissues /in rats/ following ip admin of pyridine increased with dosage. Elimination occurred in 2 phases and the duration of these phases was also dose dependent.
IP ADMIN TO MICE, HAMSTERS, RATS, GUINEA PIGS, RABBITS, & FERRETS RESULTED IN URINARY EXCRETION OF PYRIDINE N-OXIDE WHICH RANGED FROM 10% IN RATS TO APPROX 40% IN MICE & GUINEA PIGS. [GORROD JW ET AL; EUR J DRUG METAB PHARMACOKINET 5 (1): 53 (1980)] PubMed Abstract
It may enter the body through the skin.
PYRIDINE & ITS ALKYL DERIV ARE ABSORBED FROM GASTROINTESTINAL TRACT, INTRAPERITONEAL CAVITY, & LUNGS AND TO SOME EXTENT THROUGH THE SKIN. /PYRIDINE & ITS ALKYL DERIV/
Absorbed from the respiratory and gastrointestinal tracts, ... .
... Pyridine is absorbed through the gastrointestinal tract, through the skin and by inhalation.
Pyridine is absorbed through the gastrointestinal tract, skin and lungs and is eliminated via the urine, feces, skin and lungs, both as metabolites and as the parent compound. Uptake by tissues increases with dose and the elimination is biphasic in nature. Elimination is rapid and there appears to be no tissue accumulation.
Urinary excretion of pyridine & its metabolites appears to be a major route for elimination ... .
By 24 hr after ingestion of a single dose of (14)C-pyridine at 0.05 mg/kg (admin in orange juice) by humans, approx 67% of the administered 14D-label was recovered in the urine, indicating that at least 67% had been absorbed within that time period. In that same study, rats & guinea pigs that received (14)C-pyridine at 7 mg/kg excreted 58% & 76%, respectively of the (14)C-label in urine by 24 hr after admin, indicating absorption of at least those % of the admin dose. Rats admin (14)C-pyridine at 7, 68, & 357 mg/kg excreted 58%, 13%, & 20%, respectively, of the (14)C-label in their urine within 24 hr. The lower rate of excretion at higher doses suggests that the uptake of pyridine may involve nonlinear saturation kinetics.

Environmental Fate and Exposure Potential

【Environmental Fate/Exposure Summary】
TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 50(SRC), determined from a log Kow of 0.65(2) and a regression-derived equation(3), indicates that pyridine is expected to have high mobility in soil(SRC). Pyridine has a pKa of 5.23(4), which indicates that this compound will partially exist in the protonated form in moist acidic soils, and cations adsorb more strongly to soils than neutral molecules. Therefore, the mobility of pyridine is expected to be much lower in acidic soils than in neutral or alkaline soil(SRC). Volatilization of the neutral species of pyridine from moist soil surfaces is expected to be an important fate process(SRC) given a Henry's Law constant of 1.1X10-5 atm-cu m/mole(5); however, the protonated form will not volatilize(SRC). The potential for volatilization of pyridine from dry soil surfaces may exist(SRC) based upon a vapor pressure of 20.8 mm Hg(6). In a series of biodegradation tests using a soil suspension, pyridine was completely biodegraded under aerobic conditions within 66-170 days(7). Under anaerobic conditions, biodegradation was complete in 32-66 days(7).
AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 50(SRC), determined from a log Kow of 0.65(2) and a regression-derived equation(3), indicates that pyridine is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(3) based upon a Henry's Law constant of 1.1X10-5 atm-cu m/mole(4). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 3 and 25 days, respectively(SRC). The pKa of pyridine is 5.23(5), indicating this compound will partially exist in the protonated form in acidic waters and cations do not volatilize(SRC). According to a classification scheme(6), a BCF of 88 measured in guppies(7), suggests bioconcentration in aquatic organisms is moderate(SRC). The biodegradation rate constant for pyridine in water was 0.0033 - 0.018 per hour which corresponds to half-lives of 39-210 hours(8). Pyridine was completely degraded in about 8 days in a river die-away test(9). Other studies have shown that pyridine is recalcitrant in sediment and water under anaerobic conditions(10-12).
ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), pyridine, which has a vapor pressure of 20.8 mm Hg at 25 deg C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase pyridine 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 43 days(SRC), calculated from its rate constant of 3.7X10-13 cu cm/molecule-sec at 25 deg C(3).

RELATED PRODUCTS

Customer Service Hotline
Tel:+86 519 82111935
Email:info@feifanchem.com
Mobile:+86 15195055733(whats)
Address:No.4 HouYang chemical industrial park.Changzhou,Jiangsu,province,P.R.China.
CopyRight 2022 Extraordinary Pharmatech www.feifanchem.com     

  Send Email

Skype  Skype

3391543003  3391543003

 +86 15195055733

LiveChatclose