Alpha-Methylstyrene

Flammable agents - 2nd degree

Industrial compound

log Kow= 3.48

3.38

... Characteristic odor.

Sharp aromatic odor

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

0.9106

Critical volume, 3.26 ml/g; critical density, 0.29 g/ml; specific heat of liquid, 2.0460 J/g deg K at 40 °C, & 2.1757 J/g deg K at 100 °C; specific heat of vapor, 1.2357 J/g deg K at 25 °C; heat of formation of liquid, 112.97 kJ/mol at 25 °C; heat of polymerization, 39.75 kJ/mol; cubical coefficient of expansion, 9.774X10-4 at 20 °C

Relative density (water = 1): 0.91

0.91

0.913 @ 17°C

less than 1 mg/mL at 72 °F (NTP, 1992)

SOL IN ALC; SOL IN ALL PROPORTIONS IN ACETONE, CARBON TETRACHLORIDE

Sol in benzene, chloroform

Sol in ether

Sol in n-heptane, ethanol

In water, 116 mg/l @ 25 °C

129 °F (NTP, 1992)

84 °C

83.89 °C (CLOSED CUP)

57.8 °C (Cleveland open-cup)

54 °C

129 °F

329.7 °F at 760 mmHg (NTP, 1992)

165.4 °C

164 °C

330 °F

330 °F

Warning

H226: Flammable liquid and vapor [Warning Flammable liquids]

P210, P233, P240, P241, P242, P243, P261, P264+P265, P271, P273, P280, P303+P361+P353, P304+P340, P305+P351+P338, P319, P337+P317, P370+P378, P391, P403+P233, P403+P235, P405, and P501 (click each P-code to see the statement)

Danger

H226 (> 99.9%): Flammable liquid and vapor [Warning Flammable liquids]

P210, P233, P240, P241, P242, P243, P261, P264, P264+P265, P271, P273, P280, P301+P316, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P305+P354+P338, P317, P319, P321, P331, P332+P317, P337+P317, P362+P364, P370+P378, P391, P403+P233, P403+P235, P405, and P501 (click each P-code to see the statement)

Chemical: Benzene, (1-methylethenyl)-

Hazard Traits - Carcinogenicity

Council Directive (EEC) No 109/1989 (Repealed by Reg. EC No 1935/2004 (amended))

Benzene, (1-methylethenyl)- is listed on the EPA's Chemical Data Reporting (CDR) system. Manufacturers and importers of Benzene, (1-methylethenyl)- 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: 05-05-2023 https://echa.europa.eu/registration-dossier/-/registered-dossier/15309

Benzene, (1-methylethenyl)-: HSNO Approval: HSR001181 Approved with controls

Excerpt from ERG Guide 128 [Flammable Liquids (Water-Immiscible)]:

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

Flammable. Above 54 °C explosive vapour/air mixtures may be formed.

Moderate fire risk.

Readily ignites on slight heating.

Flammable

Inhalation causes irritation of respiratory tract, headache, dizziness, light-headedness, and breathlessness. Ingestion causes irritation of mouth and stomach. Contact with liquid irritates eyes. Prolonged skin contact can cause severe rashes, swelling, and blistering. (USCG, 1999)

CAUTION: Petroleum crude oil (UN1267) may contain TOXIC hydrogen sulphide gas.

Human subjects complained of an unpleasant odor and mild eye irritation. CNS depression possible after absorption of sufficient dose; TLV Basis: Irritation; Kidney & female reproductive damage; [ACGIH] A lachrymator; [CHEMINFO] A skin, eye, and respiratory tract irritant; Causes lachrymation; [ICSC]

The major hazards encountered in the use and handling of alpha-methyl styrene stem from its toxicologic properties and flammability. Toxic by all routes (ie, inhalation, ingestion, and dermal contact), exposure to this sweet-smelling, colorless liquid may occur from its use in the manufacture of acrylonitrile-butadiene-styrene resins, adhesives, waxes, and polyester resins. Effects from exposure may include irritation of the eyes, skin, and upper respiratory tract, dermatitis, and central nervous system depression. OSHA has established a 100 ppm Ceiling limit for workplace exposure until the final rule (establishing a 50 ppm time weighted average (TWA) limit) becomes effective on December 31, 1992. Engineering controls should be used to maintain airborne levels of alpha-methyl styrene to at or below the permissible limit. In activities and situations where over-exposure may occur, wear chemical protective clothing and a self-contained breathing apparatus. If contact should occur, irrigate exposed eyes with copious amounts of tepid water for at least 15 minutes, and wash exposed skin thoroughly with soap and water. Contaminatedclothing should be removed and left at the worksite for cleaning. Alpha-methyl styrene is easily ignited by heat, sparks, or flames. Its heavier-than-air vapor may travel considerable distances to a source of ignition and flash back, or form explosive concentrations in enclosed spaces such as sewers. Also, containers of alpha-methyl styrene may explode in the heat of a fire. For fires involving alpha-methyl styrene, extinguish with dry chemical, CO2, Halon, water spray or standard foam. Consider evacuation of one half mile radius, especially if a tank car or truck is involved. Alpha-methyl styrene should be stored away from heat, oxidizers, peroxides, halogens, catalysts for vinyl or ionic polymers, aluminum, and iron chloride. For small spills of alpha-methyl styrene, take up with sand or other noncombustible absorbent and place into containers for later disposal. Dike far ahead of large spills to prevent runoff. Before implementing land disposal of alpha-methyl styrene waste, consult with environmental regulatory agencies for guidance.

USEPA; Health and Environmental Effects Profile for Methyl Styrenes (1987) ECAO-CIN-G006

O'Donoghue JL; p.127-37 in Neurotoxicity of Industrial and Commercial Chemicals; O'Donoghue JL, ed (1985). The toxic effects of toluene and styrene in humans and in experimental animals were reviewed.

Excerpt from ERG Guide 128 [Flammable Liquids (Water-Immiscible)]:

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

Fresh air, rest.

Remove contaminated clothes. 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.

Rinse mouth.

· 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.

EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.

General First Aid:

(General first aid procedures)

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

50.0 [ppm]

SRP: At the time of review, criteria for land treatment or burial (sanitary landfill) disposal practices are subject to significant revision. Prior to implementing land disposal of waste residue (including waste sludge), consult with environmental regulatory agencies for guidance on acceptable disposal practices.

Personal protection: filter respirator for organic gases and vapours adapted to the airborne concentration of the substance. Do NOT let this chemical enter the environment. Ventilation. Collect leaking and spilled liquid in sealable non-metallic containers as far as possible. Absorb remaining liquid in sand or inert absorbent. Then store and dispose of according to local regulations.

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.

Avoid inhalation & skin contact.

Wear appropriate clothing to prevent repeated or prolonged skin contact. Wear eye protection to prevent any ... eye contact. Employees should wash promptly when skin is wet or contaminated. Remove nonimpervious clothing promptly if wet or contaminated.

SRP: Contaminated protective clothing should be segregated in such a manner so that there is no direct personal contact by personnel who handle, dispose, or clean the clothing. Quality assurance to ascertain the completeness of the cleaning procedures should be implemented before the decontaminated protective clothing is returned for reuse by the workers. Contaminated clothing should not be taken home at end of shift, but should remain at employee's place of work for cleaning.

For more Preventive Measures (Complete) data for ALPHA-METHYL STYRENE (6 total), please visit the HSDB record page.

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 1,900(SRC), determined from a log Kow of 3.48(2) and a regression-derived equation(3), indicates that alpha-methylstyrene is expected to have low mobility in soil(SRC). Volatilization of alpha-methylstyrene from moist soil surfaces is expected to be an important fate process(SRC) given an estimated Henry's Law constant of 2.6X10-3 atm-cu m/mole(SRC), derived from its vapor pressure, 1.9 mm Hg(4), and water solubility, 116 mg/l(5). The potential for volatilization of alpha-methylstyrene from dry soil surfaces may exist(SRC) based upon its vapor pressure(4). alpha-Methylstyrene, present at 100 mg/l, reached 0% of its theoretical BOD in 2 weeks using an activated sludge inoculum at 30 mg/l and the Japanese MITI test(6). Therefore this compound is not expected to biodegrade in soil(SRC).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 1,900(SRC), determined from a log Kow of 3.48(2) and a regression-derived equation(3), indicates that alpha-methylstyrene 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 2.6x10-3 atm-cu m/mole(SRC), derived from its vapor pressure, 1.9 mm Hg(4), and water solubility, 116 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 4 hrs and 4 days, respectively(SRC). According to a classification scheme(6), a BCF of 30 for goldfish(7), suggests the potential for bioconcentration in aquatic organisms is low(SRC). alpha-Methylstyrene, present at 100 mg/l, reached 0% of its theoretical BOD in 2 weeks using an activated sludge inoculum at 30 mg/l and the Japanese MITI test(6). Therefore this compound is not expected to biodegrade in water(SRC).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), alpha-methylstyrene, which has a vapor pressure of 1.9 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere(SRC). Vapor-phase alpha-methylstyrene is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals and ozone(SRC); the half-life for these reactions in air are estimated to be 7 and 2 hrs, respectively(SRC), calculated from rate constants of 5.2X10-11 cu cm/molecule-sec at 25 °C(3) and 1.4X10-16 cu cm/molecule-sec(4), respectively.

The substance can be absorbed into the body by inhalation.

inhalation, ingestion, skin and/or eye contact

Cough. Dizziness. Sore throat.

Redness.

Redness. Watering of the eyes.

irritation eyes, skin, nose, throat; drowsiness; dermatitis

The following link will take the user to the National Toxicology Program (NTP) Test Agent Search Results page, which tabulates all of the "Standard Toxicology & Carcinogenesis Studies", "Developmental Studies", and "Genetic Toxicity Studies" performed with this chemical. Clicking on the "Testing Status" link will take the user to the status (i.e., in review, in progress, in preparation, on test, completed, etc.) and results of all the studies that the NTP has done on this chemical. [http://ntp-apps.niehs.nih.gov/ntp_tox/index.cfm?fuseaction=ntpsearch.searchresults&searchterm=98-83-9]

OCCUPATIONAL EXPOSURE TO ALPHA-METHYL STYRENE WAS MONITORED BY MEASURING THE ATROLACTIC ACID (2-PHENYL-2-HYDROXYPROPIONIC ACID) CONTENT OF THE URINE. DETERMINATION WAS SPECTROPHOTOMETRIC.

Employees should be screened for history of certain medical conditions which might place the employee at increased risk from alpha-methyl styrene exposure. Skin disease: alpha-Methyl styrene can cause dermatitis on prolonged exposure. Persons with pre-existing skin disorders may be more susceptible to the effects of this agent. Chronic respiratory disease: In persons with impaired pulmonary function, especially those with obstructive airway diseases, the breathing of alpha-methyl styrene might cause exacerbation of symptoms due to its irritant properties or psychic reflex bronchospasm. Kidney disease: Although alpha-methyl styrene is not known as a kidney toxin in humans, the importance of this organ in the elimination of toxic substances justifies special consideration in those with possible impairment of renal function. Liver disease: Although alpha-methyl styrene is not known as a liver toxin in humans, the importance of this organ in the biotransformation and detoxification of foreign substances should be considered before exposing persons with impaired liver function.

The Koc of alpha-methylstyrene is estimated as 1,900(SRC), using a log Kow of 3.48(1) and a regression-derived equation(2). According to a classification scheme(3), this estimated Koc value suggests that alpha-methylstyrene is expected to have low mobility in soil(SRC).

alpha-Methyl styrene (CAS # 98-83-9) was evaluated for developmental toxicity in female Sprague-Dawley rats (10-13/treatment group) administered intraperitoneal injections of 0 (corn oil solvent control) or 250 mg/kg bodyweight (the maximum tolerated dose in a previous range-finding study) on Gestational Days (GD) 1 though 15. On GD 21, all animals were sacrificed for examination of treatment-related maternal toxicity, defined as a statistically significant (p < 0.05) change in at least 2 organ weights on necropsy, or fetal developmental toxicity, defined as statistically significant delay in fetal development. Treatment was associated with reproductive anomalies in treated dams relative to negative controls, including significant elevation in resorptions and a significant decrement in the fetal female sex ratio. No significant maternal gross or histologic tissue changes and no fetal visceral or skeletal malformations were attributable to treatment. Summary data only were provided.

alpha-Methyl styrene (CAS # 98-83-9, 99%) was evaluated for mutagenicity in Chinese hamster ovary cells exposed in vitro for 5 hours to concentrations of 0 (DMSO solvent control), 0.05, 0.075, 0.1, 0.125, and 0.15 uL/mL/plate with and without added Aroclor-induced rat liver S-9 mix. Concentrations were chosen from levels in a cytotoxicity study that were associated with cloning efficiencies of 108 to 0% of solvent control. A significant positive result was defined as a dose-dependent increase in mean replicate values with at least 2 consecutive doses of mutant frequencies rates in excess of 40 mutants per 10(6) clonable cells. The concurrent cytotoxicity ranging from 0 to 92% in the initial selective assay, no significant substance-related mutagenicity relative to control was observed, either in the presence or absence of metabolic activation. A confirmation assay employing concentrations of 0, 0.05, 0.075, 0.1, 0.125, and 0.135 uL/mL/plate (associated with cloning efficiencies ranging from 96 to 4%) with or without metabolic activation also failed to demonstrate significantly increased rates of mutation relative to solvent control.

Pursuant to section 8(d) of TSCA, EPA promulgated a model Health and Safety Data Reporting Rule. The section 8(d) model rule requires manufacturers, importers, and processors of listed chemical substances and mixtures to submit to EPA copies and lists of unpublished health and safety studies. Benzene, (1-methylethenyl)- is included on this list.

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. alpha-Methylstyrene is produced, as an intermediate or a final product, by process units covered under this subpart.

ALPHA-METHYLSTYRENE AT 0.1 ML ON A WATCH GLASS WAS PUT IN CONTACT WITH HUMAN SKIN & AFTER 10 MIN THE REMAINING AMOUNT WAS DISSOLVED WITH ETHYL ALC & DETERMINED BY SPECTROPHOTOMETER. THE ABSORPTION RATE OF PURE ALPHA-METHYLSTYRENE WAS 19.5 MG/SQ CM, & AQ SOLN VARIED FROM 0.048-0.256 MG/SQ CM DEPENDING ON THE TEMP & CONCN. THE EXCRETION KINETICS OF ALPHA-METHYLSTYRENE METABOLITES IS A FIRST-ORDER PROCESS.

Used as a polymerization monomer; [ACGIH]

Polymerization monomer, especially for polyesters

USED AS A THIRD MONOMER TO RAISE THE GLASS TRANSITION TEMPERATURE IN ACRYLONITRILE-BUTADIENE-STYRENE RUBBER-THERMOPLASTIC RESIN.

Polyvinyl chloride/high temperature ABS comonomer; reactive diluent (unsaturated polyester resins)

USED AS A UV DEGRADATION INHIBITOR IN ACRYLONITRILE-BUTADIENE-STYRENE RESINS

THE DOMINANT MERCHANT MARKET APPLICATION IS AS A COMONOMER IN ACRYLONITRILE-BUTADIENE-STYRENE RESINS

Contaminated by (max concn) cumene (0.15%), n-propylbenzene (0.20%), sec-butylbenzene (0.40%), tert-butylbenzene (0.40%), trans-2-phenylbutane-2 (0.05%), 2-phenylbutene-1 (0.01%), dimers (0.01%), polymers(0.01%), phenol (0.005%), and p-tert-butylcatechol (as stabilizer; 0.005%).

beta-Methylstyrene is an impurity contained in alpha-methylstyrene at a concn of about 0.5% by weight(1).

2023: 70,000,000 - <85,000,000 lb

(1972) 1.7X10+10 G (1983) 45.537x10+6 lb (USITC, 1984).

(1975) 1.36X10+10 G

(1988) 131 million lb (est as of Jan 1, 1988)

(1993) 2.25X10+10 g

62.5% AS A MONOMER FOR POLY(ALPHA-METHYL STYRENE); 37.5% FOR STYRENATED OILS FOR SURFACE COATINGS (1971)

ACRYLONITRILE-BUTADIENE-STYRENE RESINS, 34%; COATINGS, INCLUDING ADHESIVES, 14%; POLYESTER RESINS, 4%; MISCELLANEOUS, 8%; EXPORTS, 40% (1984)

/END USE PATTERN MERCHANT MARKET ONLY/ ACRYLONITRILE-BUTADIENE-STYRENE RESINS, 70%; HYDROCARBON RESINS, 15%; UNSATURATED POLYESTER & ALKYD RESINS, 10%; MISCELLANEOUS, 5% (1983)

CHEMICAL PROFILE: alpha-Methylstyrene. Demand: 1985: 48 million lb; 1986: 49 million lb; 1990 /projected/: 54.5 million lb.

For more Consumption Patterns (Complete) data for ALPHA-METHYL STYRENE (6 total), please visit the HSDB record page.

... Primarily produced as a by-product of cumene-phenol operations ... . Alkylation of benzene with propylene followed by dehydrogenation of isopropylbenzene to alpha-methylstyrene was practiced commercially by Dow until 1977.

Cumene hydroperoxide (acid-catalyzed hydrolysis; by product of phenol acetone production); cumene (dehydrogenation)

Typical chemical analysis of alpha-methylstyrene: purity, 99.3% by wt; aldehydes as CHO, 10 ppm; peroxides as hydrogen peroxide, 3 ppm; tert-butylcatechol, 15 ppm; alpha-methylstyrene, 0.5% by wt; isopropylbenzene, 0.2% by wt.

97.5% GRADE

Asphalt Paving, Roofing, and Coating Materials Manufacturing

Benzene, (1-methylethenyl)-: ACTIVE

A polymerization inhibitor such as tert-butyl catechol is usually present in commercial quantities.

AMOCO IN TEXAS CITY, TX PRODUCES APPROXIMATELY 40 MILLION POUNDS/YR /FOR CAPTIVE USE/ FOR MANUFACTURE OF THE COMPANY'S PROPRIETARY POLYMER, RESIN 18. THIS CAPTIVE PRODUCTION IS NOT REPORTED TO THE USA INTERNATIONAL TRADE COMMISSION.