Propyl mercaptan

Other Classes -> Thiols

Flammable agents - 3rd degree

log Kow = 1.81

1.81

1.7 (estimated)

Offensive

Characteristic odor of cabbage

The headspace composition changed rapidly after the onion cutting-related cell disruption. Propanethial S-oxide (the lachrymatory factor) and breakdown products dominated 0-to-10 minutes after cutting an onion. Propanethiol, dipropyl disulfide, and trace amounts of thiosulfinates then appeared, and the concentrations reached a maximum 60 minutes after cutting. Propanethiol, present at the highest concentrations, has an odor activity value is 20 times higher than dipropyl disulfide, and is suggested to be the main source of the characteristic onion odor.

0.841 at 68 °F (USCG, 1999) - Less dense than water; will float

0.843 g/cu cm at 20 °C

Relative density (water = 1): 0.84

0.842-0.847

0.8411 @ 20°C

0.84

COLORLESS, MOBILE LIQUID

Colorless liquid

Slight (NIOSH, 2024)

Miscible in ethanol, ether; very soluble in acetone

SOL IN PROPYLENE GLYCOL

Soluble in ethanol, ether, acetone, benzene

In water, 1.90X10+3 mg/L at 25 °C

1.9 mg/mL at 25 °C

5 °F (USCG, 1999)

-20 °C

-5 °F; -20.5 °C

-20 °C

-5 °F

153 °F at 760 mmHg (USCG, 1999)

67.8 °C

67.00 to 68.00 °C. @ 760.00 mm Hg

68 °C

67-68 °C

153 °F

Danger

H225 (100%): Highly Flammable liquid and vapor [Danger Flammable liquids]

P210, P233, P240, P241, P242, P243, P264, P264+P265, P270, P280, P301+P317, P303+P361+P353, P305+P351+P338, P330, P337+P317, P370+P378, P403+P235, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 1512 reports by companies from 16 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Warning

H317: May cause an allergic skin reaction [Warning Sensitization, Skin]

Chemical: 1-Propanethiol

Regulation (EC) No 1831/2003 (amended)

1-Propanethiol is listed on the EPA's Chemical Data Reporting (CDR) system. Manufacturers and importers of 1-Propanethiol are required to report information about their production and use of this chemical to the EPA under the Toxic Substances Control Act (TSCA). (40 eCFR Part 711)

Status: Active Update: 04-07-2022 https://echa.europa.eu/registration-dossier/-/registered-dossier/25232

1-Propanethiol: HSNO Approval: HSR001213 Approved with controls

The New Jersey Worker and Community Right to Know Act requires public and private employers to provide information about hazardous substances at their workplaces. (N.J.S.A. 34:5A-1 et. seq.)

Flammable Liquid

Flammable Liquid

Excerpt from ERG Guide 130 [Flammable Liquids (Water-Immiscible / Noxious)]:

Special Hazards of Combustion Products: Toxic sulfur dioxide is generated. (USCG, 1999)

· HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames.

Highly flammable. Gives off irritating or toxic fumes (or gases) in a fire. Heating will cause rise in pressure with risk of bursting. Vapour/air mixtures are explosive.

Excerpt from ERG Guide 130 [Flammable Liquids (Water-Immiscible / Noxious)]:

Inhalation causes muscular weakness, convulsions, and respiratory paralysis; high concentrations may cause pulmonary irritation. Contact with liquid causes irritation of eyes and skin. Ingestion causes irritation of mouth and stomach. (USCG, 1999)

· May cause toxic effects if inhaled or absorbed through skin.

2402 130

2402 130

Propyl mercaptan 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.

Sulfides, Organic

Sulfides, Organic

Highly Flammable

Highly Flammable

PROPANETHIOLS are flammable, moderately toxic liquid, stench. Explosive in the form of vapor when exposed to heat, flame or sparks. When heated to decomposition it emits toxic fumes of oxides of sulfur. Violent reaction and flash fire on contact with calcium hypochlorite [Stephenson, F. G., Chem. Eng. News, 1973, 51(26), p. 14].

PROPYL MERCAPTAN emits toxic fumes of oxides of sulfur when heated to decomposition. Reacts violently on contact with calcium hypochlorite [Chem. Eng. News, 1973, 51(26), p. 14].

Excerpt from ERG Guide 130 [Flammable Liquids (Water-Immiscible / Noxious)]:

Excerpt from ERG Guide 130 [Flammable Liquids (Water-Immiscible / Noxious)]:

Use powder, foam, carbon dioxide. In case of fire: keep drums, etc., cool by spraying with water.

Fresh air, rest.

Rinse and then wash skin with water and soap.

First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention.

Do NOT induce vomiting. Give one or two glasses of water to drink. Refer for medical attention .

· CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper not available or no answer, refer to appropriate telephone number listed on the inside back cover.

· ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area.

Excerpt from ERG Guide 130 [Flammable Liquids (Water-Immiscible / Noxious)]:

Excerpt from NIOSH Pocket Guide for 1-Propanethiol:

General First Aid:

(General first aid procedures)

Excerpt from ERG Guide 130 [Flammable Liquids (Water-Immiscible / Noxious)]:

Excerpt from ERG Guide 130 [Flammable Liquids (Water-Immiscible / Noxious)]:

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational exposure or environmental contamination. 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 soil or water; effects on animal, aquatic, and plant life; and conformance with environmental and public health regulations.

Ethyl mercaptan is a waste chemical stream constituent which may be subjected to ultimate disposal by controlled incineration (2,000 °F) followed by scrubbing with a caustic solution. /Ethyl mercaptan/

Incineration ... : Incinerate scrap material under controlled conditions using afterburner and a scrubber to neutralize sulfur dioxide ... . /Ethyl mercaptan/

Remove all ignition sources. Evacuate danger area! Consult an expert! Personal protection: filter respirator for organic gases and vapours adapted to the airborne concentration of the substance. Collect leaking and spilled liquid in sealable containers as far as possible. Absorb remaining liquid in sand or inert absorbent. Then store and dispose of according to local regulations. Do NOT wash away into sewer.

Work clothing that becomes wet should be immediately removed due to its flammability hazard.

Open flames and other ignition sources should be excluded from areas where thiols, especially the more volatile ones, are used. Emergency procedures and routine work practices should emphasize proper handling, containment of spills... The primary purpose of control measures is to reduce the potential for inhalation or skin contact with thiols, with special emphasis on the eyes. Whenever feasible, control at the source of exposure should be implemented. This may involve enclosure of the operation and/or the use of local exhaust ventilation. /Thiols/

Safety showers, eye wash fountains and fire extinguishers should be located in areas where appreciable amounts of thiols are used. Handwashing facilities, soap and water, should be made available to involved employees. /Thiols/

Clothing which is contaminated with ethyl mercaptan should be removed immediately and placed in closed containers for storage until it can be discarded or until provision is made for the removal of ethylmercaptan from the clothing. If the clothing is to be laundered or cleaned, the person performing the operation should be informed of ethyl mercaptan's hazardous properties. /Ethyl mercaptan/

For more Preventive Measures (Complete) data for PROPYL MERCAPTAN (12 total), please visit the HSDB record page.

Cysteine, 2-propanethiol, and 2-mercaptoethylamine were found to potentiate the action of bradykinin on the rat blood pressure. These same thiols were ineffective on the in vitro rat ileum, although on the guinea pig ileum only 2-propanethiol was observed to be ineffective.

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 230(SRC), determined from a log Kow of 1.81(2) and a regression-derived equation(3), indicates that propyl mercaptan is expected to have moderate mobility in soil(SRC). Volatilization of propyl mercaptan from moist soil surfaces is expected to be an important fate process(SRC) given a Henry's Law constant of 4.08X10-3 atm-cu m/mole(4). Propyl mercaptan is expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 154 mm Hg(5). Slow bio-oxidation using a Warburg respirometer with Alcaligenes faecalis(6) suggests that biodegradation is not an important environmental fate process.

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 230(SRC), determined from a log Kow of 1.81(2) and a regression-derived equation(3), indicates that propyl mercaptan is expected to adsorb moderately to suspended solids and sediment(SRC). Volatilization from water surfaces is expected to be an important environmental fate process(3) based upon a Henry's Law constant of 4.08X10-3 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 2.6 hours and 3.5 days, respectively(SRC). According to a classification scheme(5), an estimated BCF of 5(SRC), from its log Kow(2) and a regression-derived equation(6), suggests the potential for bioconcentration in aquatic organisms is low(SRC). The concentration of propyl mercaptan decreased over a distance of 0 to 54 meters using lysimeters to simulate dump leachate movement in groundwater indicating biotic degradation in soil(7); however, slow biooxidation using a Warburg test(8) suggests that biodegradation not an important environmental fate process(SRC).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), propyl mercaptan, which has an extrapolated vapor pressure of 154 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase propyl mercaptan 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 8 hours(SRC), calculated from its rate constant of 4.83X10-11 cu cm/molecule-sec at 25 °C(3). Propyl mercaptan does not absorb light at wavelengths >290 nm and therefore is not expected to be susceptible to direct photolysis by sunlight.

The substance can be absorbed into the body by inhalation and by ingestion.

inhalation, ingestion, skin and/or eye contact

Cough. Drowsiness. Dizziness. Headache. Nausea.

Redness.

Redness. Pain.

See Inhalation.

irritation eyes, skin, nose, throat, respiratory system; headache, nausea, dizziness, cyanosis; In Animals: liver, kidney damage

Propyl mercaptan was qualitatively detected in exhaust gases collected from the sulfate and semi-alkaline pulping processes of a Finish pulp mill(1). The compound was identified as a component of landfill gas collected from domestic waste disposal sites in Augsbach and Munich, Germany but not sewage gas collected from treatment plants in Munich, Germany(2).

Prior to placing a worker in a job with a potential for exposure to ethyl mercaptan, the physician should evaluate and document the worker's baseline health status with thorough medical, environmental, and occupational histories, a physical examination, and physiologic and laboratory tests appropriate for the anticipated occupational risk. These should concentrate on the function and integrity of the nervous and respiratory systems. Medical surveillance for respiratory disease should be conducted by using the principles and methods recommended by NIOSH and the American Thoracic Society (ATS). A preplacement medical evaluation is recommended in order to detect and assess preexisting or concurrent conditions which may be aggravated or result in increased risk when a worker is exposed to n-butyl mercaptan at or below the NIOSH REL. The examining physician should consider the probable frequency, intensity, and duration of exposure, as well as the nature and degree of the condition, in placing such a worker. Such conditions, which should not be regarded as absolute contraindications to job placement, include chronic diseases of the respiratory system. /Ethyl mercaptan/

Propyl mercaptan 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.

The enzyme system responsible for conversion of endogenous toxic mercaptans into nontoxic thioether products via methylation, ie, alkane thiol s-methyltransferase is located in endoplasmic reticulum and can be extracted through detergent solubilization. /Mercaptans/

...May directly be oxidized and readily excreted as propane sulfate. Propylmercaptan binds to microsomal cytochrome P-450 in vitro and inhibits carbonic anhydrase. ... Completely inhibits formation of sclerotium in Sclerotimus rolfsii. Propylmercaptan can be degraded by enzymatic action of liver microsomes.

Simple aliphatic and aromatic thiols undergo S-methylation in mammals to produce the corresponding methyl thioether or sulfide. Methylation is catalysed by thiopurine methyltransferase in the cytoplasm and thiol methyltransferase in microsomes, and both reactions require S-adenosyl-l-methionine as a methyl group donor. Thiopurine methyltransferase is present in human liver, kidney, and erythrocytes; preferential substrates for this enzyme include aromatic and heterocyclic thiols. S-Methylation of aliphatic thiols is catalysed by microsomal thiol methyltransferase, and the resulting methyl thioether (sulfide) metabolite would undergo S-oxidation to give the methyl sulfoxide and methyl sulfone analogues as urinary products. Thiols may react with glutathione and other endogenous thiol substances to form mixed disulfides. Both microsomal and cytoplasmic thioltransferasess have been reported to catalyse the formation of mixed disulfides. The resulting mixed disulfides can undergo reduction back to thiols, oxidative desulfuration, or oxidation to a sulfonic acid via the intermediate thiosulfinate and sulfinic acids. The principal form in the circulation would probably be a mixed disulfide formed with albumin. /Simple thiols/

Used as a synthetic flavoring agent, and as an odorant of odorless, toxic gases; as a fungicide or as fungicidal component. [HSDB]

Synthetic flavoring agent

Chemical intermediate; herbicide

Synthetic chemical reactions; as an odorant of odorless, toxic gases; as a fungicide or as fungicidal component.

2023: 1,000,000 - <8,500,000 lb

1-Propanethiol is listed as a High Production Volume (HPV) chemical (65FR81686). Chemicals listed as HPV were produced in or imported into the U.S. in >1 million pounds in 1990 and/or 1994. The HPV list is based on the 1990 Inventory Update Rule. (IUR) (40 CFR part 710 subpart B; 51FR21438).

(1991) Exceeded 5000 lb

/It is prepared/ by reacting propyl alcohol & hydrogen sulfide ... Sabatier et al, Compt Rend Seanc Acad Sci (paris), 150: 1219, 1910; from propyl alcohol or propyl disulfide & naphthalene ... Mereshkoski, Chem Zentrabl, 86, 982, 1915; Faragher et al, Chem Zentralbl, 99, 119, 1928; from n-propyl chloride & potassium hydrosulfide; also from n-propanol plus bromine plus red phosphorus in presence of sodium sulfate.

Thiols can be prepared by a variety of methods. The most-utilized of these synthetic methods for tertiary and secondary thiols is acid-catalyzed synthesis; for normal and secondary thiols, the most-utilized methods are free-radical-initiated, alcohol substitution, or halide substitution; for mercaptoalcohols, the most-utilized method is oxirane addition; and for mercaptoacids and mercaptonitriles, the most-utilized methods are Michael-type additions. /Thiols/

Flavouring Agent -> FLAVOURING_AGENT -> JECFA Functional Classes

Flavoring Agents -> JECFA Flavorings Index

Flavouring Agent -> FLAVOURING_AGENT -> JECFA Functional Classes

Flavouring Agent -> FLAVOURING_AGENT -> JECFA Functional Classes

Utilities

1-Propanethiol: ACTIVE