1-Pentanethiol

Other Classes -> Thiols

Flammable agents - 3rd degree

Penetrating, unpleasant odor

Meaty odor

Strong, offensive odor

... Strong garlic-like odor.

0.8392 at 77 °F (USCG, 1999) - Less dense than water; will float

0.850 g/cu cm at 20 °C

Bulk density = 6.99 lb/gal; density: 0.83-0.84 at 20 °C; mercaptan content greater than 90%; initial BP above 104.0 °C, final below 120 °C ... These properties vary with proportions of isomers

Relative density (water = 1): 0.84

0.831-0.844

0.84

Liquid

Water-white to yellowish liquid ...

Water-white to light-yellow liquid

Colorless liquid

Insoluble (NIOSH, 2024)

In water, 156 mg/L at 20 °C

In water, 156 mg/L at 25 °C

Insoluble in water

Miscible with ethanol, ether

0.156 mg/mL at 20 °C

65 °F (USCG, 1999)

18 °C

18 °C (64 °F) - closed cup

65 °F (18 °C) (Open cup)

18 °C

(oc) 65 °F

248 °F at 760 mmHg (USCG, 1999)

126.6 °C

BP: 123-124 °C

at 61.3kPa: 126.6 °C

124-126 °C

260 °F

-105 °F (USCG, 1999)

-75.69 °C

Liquid molar volume = 0.124405 cu m/kmol. Heat of formation = -1.0979X10+8 J/kmol. Heat of fusion = 1.7531X10+7 J/kmol at melting point.

-75.7 °C

-75.7 °C

-104 °F

Danger

H225 (12.6%): Highly Flammable liquid and vapor [Danger Flammable liquids]

P210, P233, P240, P241, P242, P243, P261, P264, P270, P271, P280, P301+P317, P303+P361+P353, P304+P340, P317, P330, P370+P378, P403+P235, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 1472 reports by companies from 8 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Danger

H225: Highly Flammable liquid and vapor [Danger Flammable liquids]

Chemical: 1-Pentanethiol

Commission Regulation (EC) No 1565/2000 (Repealed by Com. Implementing Reg. (EU) No 872/2012)

1-Pentanethiol: Does not have an individual approval but may be used under an appropriate group standard

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.)

Special Hazards of Combustion Products: Sulfur dioxide gas is formed

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

Highly flammable. Gives off irritating or toxic fumes (or gases) in a fire. Vapour/air mixtures are explosive.

A flammable liquid and dangerous fire hazard when exposed to heat or flame ... .

Technical butanethiol (containing 28% of propane- and 7% of pentanethiols) is hypergolic with 96% acid.

Oxidation of several thiols to the sulfonic acids by addition to stirred concentrated acid had been effected normally, but when 2 new batches of pentanethiol were used, flame was observed in the vapor phase a few seconds after addition. No unusual impurities were detected.

Flammable liquid.

Inhalation may cause nausea because of offensive odor. Contact with eyes or skin causes slight irritation. Ingestion may cause vomiting. (USCG, 1999)

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

1111 130

1111 130

This action promulgates standards of performance for equipment leaks of Volatile Organic Compounds (VOC) in the Synthetic Organic Chemical Manufacturing Industry (SOCMI). The intended effect of these standards is to require all newly constructed, modified, and reconstructed SOCMI process units to use the best demonstrated system of continuous emission reduction for equipment leaks of VOC, considering costs, non air quality health and environmental impact and energy requirements. Amyl mercaptan is produced, as an intermediate or final product, by process units covered under this subpart.

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

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

Fresh air, rest. Refer for medical attention.

Remove contaminated clothes. Rinse skin with plenty of water or shower.

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

Rinse mouth. Give one or two glasses of water to drink. Do NOT induce vomiting. 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 NIOSH Pocket Guide for 1-Pentanethiol:

General First Aid:

(General first aid procedures)

Suitable extinguishing media: For small (incipient) fires, use media such as "alcohol" foam, dry chemical, or carbon dioxide. For large fires, apply water from as far as possible. Use very large quantities (flooding) of water applied as a mist or spray; solid streams of water may be ineffective. Cool all affected containers with flooding quantities of water.

Advice for firefighters: Wear self-contained breathing apparatus for firefighting if necessary.

Use water spray to cool unopened containers.

To fight fire, use foam, /carbon dioxide/, dry chemical.

For more Fire Fighting Procedures (Complete) data for n-Amyl mercaptan (6 total), please visit the HSDB record page.

Store in cool place. Keep container tightly closed in a dry and well-ventilated place. Containers which are opened must be carefully resealed and kept upright to prevent leakage. Light sensitive. Store under inert gas. Moisture sensitive. Stench.

Store in a cool, dry, well-ventilated location. Separate from oxidizing materials. Outside or detached storage is preferred. Inside storage should be in a standard flammable liquids storage warehouse, room, or cabinet.

ACCIDENTAL RELEASE MEASURES: Personal precautions, protective equipment and emergency procedures: Use personal protective equipment. Avoid breathing vapors, mist or gas. Ensure adequate ventilation. Remove all sources of ignition. Evacuate personnel to safe areas. Beware of vapors accumulating to form explosive concentrations. Vapors can accumulate in low areas. Environmental precautions: Prevent further leakage or spillage if safe to do so. Do not let product enter drains. Methods and materials for containment and cleaning up: Contain spillage, and then collect with an electrically protected vacuum cleaner or by wet-brushing and place in container for disposal according to local regulations.

Emergency response personal protective equipment: Wear full protective clothing and positive pressure self-contained breathing apparatus. Spill or leak procedures: Eliminate all ignition sources. Stop or control the leak, if this can be done without undue risk. Control runoff and isolate discharged material for proper disposal.

Personal protection: filter respirator for organic gases and vapors adapted to the airborne concentration of the substance. Remove all ignition sources. Cover the spilled material with absorbent material. Sweep spilled substance into sealable containers. Do NOT wash away into sewer.

SRP: 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 air, soil or water; effects on animal, aquatic and plant life; and conformance with environmental and public health regulations. If it is possible or reasonable use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination.

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. If it is not practicable to manage the chemical in this fashion, it must be evaluated in accordance with EPA 40 CFR Part 261, specifically Subpart B, in order to determine the appropriate local, state and federal requirements for disposal.

Product: Burn in a chemical incinerator equipped with an afterburner and scrubber but exert extra care in igniting as this material is highly flammable. Offer surplus and non-recyclable solutions to a licensed disposal company. Contact a licensed professional waste disposal service to dispose of this material; Contaminated packaging: Dispose of as unused product.

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 130(SRC), determined from a structure estimation method(2), indicates that n-amyl mercaptan is expected to have moderate mobility in soil(SRC). Volatilization of n-amyl mercaptan from moist soil surfaces is expected to be an important fate process(SRC) given an estimated Henry's Law constant of 1.2X10-2 atm-cu m/mole(SRC), based upon its vapor pressure, 13.8 mm Hg(3), and water solubility, 156 mg/L(4). n-Amyl mercaptan is expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure(3). Biodegradation data in soil were not available(SRC, 2018).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 130(SRC), determined from a structure estimation method(2), indicates that n-amyl mercaptan is expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(3) based upon an estimated Henry's Law constant of 1.2X10-2 atm-cu m/mole(SRC), derived from its vapor pressure, 13.8 mm Hg(4), and water solubility, 156 mg/L(5). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 3 hours and 4 days, respectively(SRC). According to a classification scheme(6), an estimated BCF of 30(SRC), from an estimated log Kow of 2.74(2) and a regression-derived equation(2), suggests the potential for bioconcentration in aquatic organisms is low to moderate(SRC). Biodegradation data in water were not available(SRC, 2018).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), n-amyl mercaptan, which has a vapor pressure of 13.8 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase n-amyl 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 hrs(SRC), calculated from its rate constant of 4.6X10-11 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). n-Amyl mercaptan absorbs UV light at wavelength 210 nm(4) and, therefore, is not expected to be susceptible to direct photolysis since sunlight consists of wavelengths above 290 nm(SRC).

The substance can be absorbed into the body by inhalation of its aerosol.

inhalation, ingestion, skin and/or eye contact

IDENTIFICATION AND USE: Amyl mercaptan is a liquid. It is used as an intermediate in the synthesis of organic sulfur compounds and as a synthetic flavoring agent. It is the chief constituent of the odorant used in gas lines to locate leaks. HUMAN STUDIES: Potential symptoms of overexposure include headache, nausea, dizziness, vomiting, diarrhea, dermatitis, skin sensitization, and irritation of eyes, skin, nose, throat, and respiratory system. ANIMAL STUDIES: No skin irritation was reported in rabbits after a 24 hr exposure, but marked eye irritation in rabbits lasted for 3 days. A range-finding study found inhalation of 2000 ppm for 4 hr killed two to four rats out of six exposed. In rats, amyl mercaptan produced stomach ulcers and adrenal gland damage at dosages that cause 70-100% mortality in 5 days.

Headache. Nausea. Cough.

Redness. Pain.

Redness. Pain.

Burning sensation in the throat and chest. Headache. Nausea.

irritation eyes, skin, nose, throat, respiratory system; headache, nausea, dizziness; vomiting, diarrhea; dermatitis, skin sensitization

Using a structure estimation method based on molecular connectivity indices(1), the Koc of n-amyl mercaptan can be estimated to be 130(SRC). According to a classification scheme(2), this estimated Koc value suggests that n-amyl mercaptan is expected to have high mobility in soil(SRC).

n-Amyl mercaptan is reported to be found in nature(1).

Small quantities /of n-amyl mercaptan/ occur in natural gas deposits with crude oil or in decaying animal or plant tissue.

n-Amyl mercaptan's production and use as an intermediate in the synthesis of organic sulfur compounds and synthetic flavoring agent(1,2) may result in its release to the environment through various waste streams(SRC). Its use as an odorant used in gas lines to locate leaks(1,2) will result in its direct release to the environment(SRC).

PURE CULTURE: n-Amyl mercaptan, present at 500 mg/L, exhibited 375 mg/L O2 uptake in 168 hours using an activated sludge microbe (Alcaligenes faecalis) inoculum at 2,500 bacterial cells/L and the Warburg respirometer test at 20 °C(1). In general, thiol chemicals, such as n-amyl mercapatan, were not as readily oxidized as were the corresponding alcohols(1). However, pure culture studies such as this are not appropriate for evaluating environmental biodegradation(2).

This action promulgates standards of performance for equipment leaks of Volatile Organic Compounds (VOC) in the Synthetic Organic Chemical Manufacturing Industry (SOCMI). The intended effect of these standards is to require all newly constructed, modified, and reconstructed SOCMI process units to use the best demonstrated system of continuous emission reduction for equipment leaks of VOC, considering costs, non air quality health and environmental impact and energy requirements. Amyl mercaptan is produced, as an intermediate or final product, by process units covered under this subpart.

Synthesis of organic sulfur compounds; chief constituent of odorant used in gas lines to locate leaks. Also used as a synthetic flavoring ingredient. [HSDB]

In organic synthesis,

For 1-pentanethiol (USEPA/OPP Pesticide Code: 100701) there are 0 labels match. /SRP: Not registered for current 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./

Reported uses (ppm):

Synthesis of organic sulfur compounds; chief constituent of odorant used in gas lines to locate leaks.

n-Pentyl mercaptan is used as an intermediate in the synthesis of organic sulfur compounds and as a synthetic flavoring agent. It is the chief constituent of the odorant used in gas lines to locate leaks.

It is manufactured either from 2-methyl-1-butylisothiourea picrate by conversion to (S)-2-methylbutyl disulfide, followed by reduction to the corresponding thiol using sodium metal in liquid ammonia or by mixing amyl bromide and potassium hydrosulfide in alcohol.

Mixing amyl bromide and potassium hydrosulfide in alcohol.

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/

Grades or Purity: 96.0+%

98% grade

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

Flavouring Agent -> FLAVOURING_AGENT -> JECFA Functional Classes

Flavouring Agent -> FLAVOURING_AGENT -> JECFA Functional Classes