Butan-1-thiol

Other Classes -> Thiols

Flammable agents - 3rd degree

log Kow = 2.28

2.28

2.28

Strong, obnoxious odor

Heavy skunk odor

Strong, garlic-, cabbage-, or skunk like odor.

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

0.83679 at 25 °C/4 °C

Relative density (water = 1): 0.83

0.842-0.847

0.83

0.8416 @ 20°C

Colorless liquid

Mobile liquid

0.06 % (NIOSH, 2024)

Slightly soluble in chloroform

Very soluble in alcohol, ether, liquid hydrogen sulfide

In water, 595 mg/L at 25 °C

0.597 mg/mL at 20 °C

Solubility in water, g/100ml: 0.06

55 °F (USCG, 1999)

2 °C

35 °F (2 °C) (Closed cup)

2 °C c.c.

55 °F

35 °F

Danger

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

P210, P233, P240, P241, P242, P243, P261, P264, P264+P265, P270, P271, P280, P301+P317, P303+P361+P353, P304+P340, P305+P351+P338, P317, P330, P337+P317, P370+P378, P403+P235, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 1734 reports by companies from 15 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-Butanethiol

1-Butanethiol is listed on the EPA's Chemical Data Reporting (CDR) system. Manufacturers and importers of 1-Butanethiol 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: 06-04-2022 https://echa.europa.eu/registration-dossier/-/registered-dossier/20075

1-Butanethiol: 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: Irritating sulfur dioxide may form.

· 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.

Dangerous by exposure to heat, flame, sparks or powerful oxidizers.

Highly flammable. Gives off irritating or toxic fumes (or gases) in a fire.

Vapor/air mixtures are explosive.

Inhalation causes loss of sense of smell; muscular weakness. convulsions, and respiratory paralysis may follow prolonged exposure. Contact of liquid with eyes or skin causes slight irritation. Ingestion causes nausea. (USCG, 1999)

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

In four hour inhalation studies, rats and mice show central nervous system depression. Oral and intraperitoneal doses at near lethal levels injure the liver and kidneys. Workers exposed in an accident to 50-500 ppm for one hour experienced weakness, sweating, headache, and vomiting. One of these workers lost consciousness for 20 minutes. [ACGIH] See THIOLS.

2347 130

2347 130

Toxicology card. 190. Methanethiol (CH3-SH), ethanethiol (C2H5-SH), and 1-butanethiol (C4-H9-SH); Cah Notes Doc 113: 597-600 (1983). Review of safety, health hazard & safety in processing & handling of butanethiol, ethanethiol & methanethiol.

New Active Ingredients ... includes pesticide active ingredients initially registered after November 1, 1984, that currently have active product registrations. By law, these newer pesticides are not subject to the reregistration program. They must, however, meet the new safety standard of the FQPA, and will be reviewed on a 15-year cycle under the registration review program. ... Active Ingredient Number: 125001; Type of Pesticide: insecticide - animal repellant; Use Site: non-food use; Year: 1995.

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

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

Fresh air, rest. Artificial respiration may be needed. Refer for medical attention.

Remove contaminated clothes. Rinse skin with plenty of water or shower. Refer for medical attention .

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

Rinse mouth. 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 n-Butyl mercaptan:

General First Aid:

(General first aid procedures)

· Wear positive pressure self-contained breathing apparatus (SCBA).

0.5 [ppm]

Alcohol foam. Water may be ineffective.

If material /is/ on fire or involved in /a/ fire: Do not extinguish fire unless flow can be stopped. Use water in flooding quantities as fog. Solid streams of water may spread fire. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. Use "alcohol" foam, dry chemical or carbon dioxide.

Fireproof. Separated from strong oxidants, acids.

... Acids should not be stored in close proximity to /butyl mercaptan/.

If n-butyl mercaptan is spilled or leaked, the following steps should be taken: 1. Remove all ignition sources. 2. Ventilate area of spill or leak. 3. For small quantities of liquids contaning n-butyl mercaptan, absorb on paper towels and place in an appropriate container. Place towels in a safe place such as a fume hood for evaporation. Allow sufficient time for evaporation of the vapors so that the the hood ductwork is free from n-butyl mercaptan vapors. Burn the paper in a suitable location away from combustible materials. 4. Large quantities of liquids containing n-butyl mercaptan may be absorbed in vermiculite, dry sand, earth, or a similar material and placed in an appropriate container. n-Butyl mercaptan should not be allowed to enter a confined space such as a sewer because of the possibility of an explosion. 5. Liquids containing n-butyl mercaptan may be collected by vacuuming with an appropriate system. If a vacuum system is used, there should be no sources of ignition in the vicinity of the spill, and flashback prevention devices should be provided.

Evacuate danger area! Remove all ignition sources. Collect leaking and spilled liquid in sealable containers as far as possible. Absorb remaining liquid in sand or inert absorbent and remove to safe place. Do NOT wash away into sewer. Do NOT let this chemical enter the environment. Chemical protection suit including self-contained breathing apparatus.

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/

A potential candidate for fluidized bed incineration at a temperature range of 450 to 980 °C and residence times of seconds for liquids and gases, and longer for solids. A potential candidate for rotary kiln incineration at a temperature range of 820 to 1,600 °C and residence times of seconds for liquids and gases, and hours for solids. /Mmethyl mercaptan/

Evacuate danger area! Personal protection: chemical protection suit including self-contained breathing apparatus. Remove all ignition sources. Do NOT let this chemical enter the environment. 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.

... We tested whether propanol, butanol, propanethiol, and butanethiol enhance the effect of glycine on alpha1 glycine receptors expressed in Xenopus laevis oocytes in a manner that reflects the in vivo differences found for potencies /was tested/. As anticipated, we found an immediate parallel between in vivo (rat minimum alveolar concentration of anesthetic required to eliminate movement in response to a noxious stimulus in 50% of subjects) and in vitro (recombinant receptor) effects. All four compounds enhanced the effect of glycine on wild type receptors, and the extent of enhancement for a given minimum alveolar concentration-multiple was approximately the same for all compounds. We also found that propanethiol, butanethiol, propanol, and butanol did not affect, or minimally affected, the action of glycine in anesthetic resistant mutants in which the amino acid serine at position 267 was replaced by glutamine [alpha1(S267Q)]. The in vivo potencies of propanethiol, butanethiol, propanol, and butanol correlate with their capacities to enhance the effect of glycine on alpha1 glycine receptors expressed in Xenopus laevis oocytes.

EC50 Scenedesmus subspicatus (Green algae; growth inhibition) 1068.3-5478.24 mg/L/96 hr; static

LC50 Ictalurus punctatus (Channel catfish) 1100-3600 mg/L/96 hr; static /formulated product/

LC50 Lepomis macrochirus 7.4 mg/L/24 hr /Conditions of bioassay not specified in source examined/

LC50 Lepomis macrochirus 5.5 mg/L/48 hr /Conditions of bioassay not specified in source examined/

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 410(SRC), determined from a log Kow of 2.28(2) and a regression-derived equation(3), indicates that 1-butyl mercaptan is expected to have moderate mobility in soil(SRC). Volatilization of 1-butyl mercaptan from moist soil surfaces is expected to be an important fate process(SRC) given a Henry's Law constant of 4.54X10-3 atm-cu m/mole(4). 1-Butyl mercaptan is expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 45.5 mm Hg(5). Biodegradation data were not available(SRC, 2005).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 410(SRC), determined from a log Kow of 2.28(2) and a regression-derived equation(3), indicates that 1-butyl mercaptan is expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(3) based upon a Henry's Law constant of 4.54X10-3 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 3 hours and 4 days, respectively(SRC). According to a classification scheme(5), an estimated BCF of 11(SRC), from its log Kow(2) and a regression-derived equation(6), suggests the potential for bioconcentration in aquatic organisms is low(SRC). Biodegradation data were not available(SRC, 2005), however an anaerobic lysimeter study of a contaminated dump aquifer in Germany showed a decrease in 1-butyl mercaptan concentration within 5 m of source input(7).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 1-butyl mercaptan, which has a vapor pressure of 45.5 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase 1-butyl 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 9 hours(SRC), calculated from its rate constant of 5.1X10-11 cu cm/molecule-sec at 25 °C(3). 1-Butyl mercaptan does not absorb light at wavelengths >290 nm(4) and therefore is not expected to be susceptible to direct photolysis by sunlight(SRC).

The substance can be absorbed into the body by inhalation.

inhalation, ingestion, skin and/or eye contact

/AQUATIC SPECIES/ In 21-day studies, concentrations greater than 80 mg/L caused significant and persistent increases in methemoglobin in the catfish starting on day 2. The concentration in water that can cause tainting of fish and other aquatic organisms is 60 mg/L.

/AQUATIC SPECIES/ Indicators of free-radical or oxidant mediated responses were quantified in channel catfish, Ictalurus punctatus exposed to the organophosphorus herbicide DEF and its metabolite, n-butyl mercaptan. The activities of the antioxidant enzymes superoxide dismutase, glutathione peroxidase and catalase did not vary significantly with toxicant or dose. The concentration of reduced glutathione and malondialdehyde did not vary significantly with toxicant or dose. The percentage of methemoglobin increased in the n-butyl mercaptan exposed fish with dose, up to 16.5% of total hemoglobin. The DEF exposed catfish had no significant increases in methemoglobin compared to controls.

Weakness. Confusion. Cough. Dizziness. Drowsiness. Headache. Nausea. Vomiting. Shortness of breath.

Redness. Pain.

Redness. Pain.

See Inhalation.

irritation eyes, skin; muscle weak, malaise (vague feeling of discomfort), sweating, nausea, vomiting, headache, confusion; In Animals: narcosis, incoordination, lassitude (weakness, exhaustion); cyanosis, pulmonary irritation; liver, kidney damage

Prior to placing a worker in a job with a potential for exposure to n-butyl 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.

The Koc of 1-butyl mercaptan is estimated as 410(SRC), using a log Kow of 2.28(1) and a regression-derived equation(2). According to a classification scheme(3), this estimated Koc value suggests that 1-butyl mercaptan is expected to have moderate mobility in soil.

New Active Ingredients ... includes pesticide active ingredients initially registered after November 1, 1984, that currently have active product registrations. By law, these newer pesticides are not subject to the reregistration program. They must, however, meet the new safety standard of the FQPA, and will be reviewed on a 15-year cycle under the registration review program. ... Active Ingredient Number: 125001; Type of Pesticide: insecticide - animal repellant; Use Site: non-food use; Year: 1995.

The metabolic pathways of thiols include oxidation to unstable sulfenic acids (RSOH), which may be oxidized to the corresponding sulfinic (RSO2H) and sulfonic acids (RSO3H); methylation to yield methyl sulfides, which can be oxidized to methyl sulfoxides and sulfones; reaction with endogenous thiols such as glutathione to form mixed disulfides; conjugation with glucuronic acid; and oxidation of the alpha-carbon resulting in desulfuration and formation of an aldehyde intermediate. /Thiols/

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 solvent, an odorant for natural gas, and an intermediate for insecticides and herbicides; [ACGIH]

For n-butyl mercaptan (USEPA/OPP Pesticide Code: 125001) ACTIVE products with label matches. /SRP: Registered for 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./

As solvent

Intermediate for insecticides, acaricides, herbicides, defoliants

...As an odorant.

For more Uses (Complete) data for 1-BUTYL MERCAPTAN (6 total), please visit the HSDB record page.

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

1-Butanethiol 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).

(1972) Probably greater than 4.54X10+5 GR

(1991) Exceeded 5000 lb or US $5000 in value

Reaction of n-butylene with hydrogen sulfide in the presence of a catalyst

Formed by the action of yeast on a product obtained when hydrogen sulfide is made to react with butyraldehyde in alcoholic ammonia; ... by passing vapors of butanol and hydrogen sulfide over thorium oxide catalyst; ... together with dibutyl sulfide in distilling an aqueous solution of sodium butyl sulfate and sodium sulfide; ... by slightly warming dithiocarbamic butyl ester with aqueous potassium hydroxide.

Flavouring Agent -> FLAVOURING_AGENT -> JECFA Functional Classes

Flavoring Agents -> JECFA Flavorings Index

Flavouring Agent -> FLAVOURING_AGENT -> JECFA Functional Classes

Pesticide, Fertilizer, and Other Agricultural Chemical Manufacturing

1-Butanethiol: ACTIVE

Once cited to occur in "skunk" fluid.

Synthetic flavoring substance and adjuvants: n-butyl-mercaptan

1-Butyl mercaptan is a formulation impurity in the defoliants DEF (s,s,s-tributyl phosphorotrithioate) and Folex /former/ (merphos, s,s,s-tributyl phosphorotrithioite), two major defoliants used in the US as cotton harvest aides.

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/