Inden

Other Classes -> Aromatic Hydrocarbons

Flammable agents - 2nd degree

0.997 (NIOSH, 2024) - Less dense than water; will float

0.9968 @ 20 °C/4 °C

0.997

0.996 @25 °C

0.997

LIQUID

Colorless liquid

Colorless liquid [Note: A solid below 29 degrees F].

Insoluble (NIOSH, 2024)

INSOL IN WATER, MISCIBLE WITH MOST ORGANIC SOLVENTS

SOL IN ALL PROPORTIONS IN ALC, ETHER, N BENZENE, PYRIMIDENE, CARBON DISULFIDE

Soluble in ethanol; it is miscible with diethyl ether, naphtha, pyridine, carbon tetrachloride, chloroform, and carbon disulfide

Insoluble

173 °F (NIOSH, 2024)

173 °F

173 °F

173 °F

173 °F

359 °F at 760 mmHg (NIOSH, 2024)

181.6 °C 760 MM HG

359 °F

182 °C @760 [mm Hg]

359 °F

29 °F (NIOSH, 2024)

-1.8 °C

29 °F

-1.5 °C

29 °F

1.1 [mmHg]

1.1 mm Hg at 25 °C

0.75 [mm Hg] @12 °C

This chemical does not meet GHS hazard criteria for 0.5% (2 of 400) of reports.

Danger

H226 (99.2%): Flammable liquid and vapor [Warning Flammable liquids]

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

Aggregated GHS information provided per 400 reports by companies from 16 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Danger

Chemical: 1H-Indene

1H-Indene is listed on the EPA's Chemical Data Reporting (CDR) system. Manufacturers and importers of 1H-Indene 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: 26-02-2019 https://echa.europa.eu/registration-dossier/-/registered-dossier/27751

Indene: 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.)

INDENE is combustible (flash point between 140 °F and 200 °F). Polymerizes and oxidizes on standing in the air. This reaction is accelerated by heating, acids, and catalysts, including peroxides. Has exploded during nitration with a mixture of H2SO4 and HNO3.

Excerpt from NIOSH Pocket Guide for Indene:

(General first aid procedures)

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.

The worker should wash daily at the end of each work shift.

Work clothing that becomes wet or significantly contaminated should be removed and replaced.

5.0 [ppm]

8 hr Time Weighted Avg (TWA): 5 ppm.

Excursion Limit Recommendation: Excursions in worker exposure levels may exceed 3 times the TLV-TWA for no more than a total of 30 minutes during a work day, and under no circumstances should they exceed 5 times the TLV-TWA, provided that the TLV-TWA is not exceeded.

5 ppm [2007]

10 ppm (45 mg/m³) OSHA Construction and Maritime industries only.

none See Appendix G

70 [mg/m3]

100 [mg/m3]

620 [mg/m3]

10 ppm (45 mg/m³)

TWA 10 ppm (45 mg/m3)

Excerpt from NIOSH Pocket Guide for Indene:

Wear appropriate personal protective clothing to prevent skin contact.

Wear appropriate eye protection to prevent eye contact.

Indene was detected in respiratory gas from 7 of 8 male volunteers (3 smokers) at a concn range of 0.14-83 ug/hr-expired air; according to this study, indene may result from or be related to normal human metabolism(1). Indene was found at an average concn of 0.138 ng/L in 59 of 387 expired air samples obtained from 54 nonsmoking-volunteers(2).

TERRESTRIAL FATE: The estimated Koc value of 540(1-2,SRC) suggests that indene will have low mobility in soil(3). If spilled on soil surfaces, some indene may photolyze(4,SRC) or volatilize into the air (estimated Henry's Law constant of 1.59X10-3 atm-cu m/mol at 25 °C(5)). However, adsorption may limit these processes(SRC). Limited data suggest indene is biodegradable in soil(6-7).

AQUATIC FATE: Based on the estimated Koc value of 540(1-2,SRC), indene may adsorb to sediment; indene was found in a river sediment(3). Oxidation via reaction with sunlight produced alkyl peroxy radicals is very slow (estimated half-life of 1,100 days(4)). Limited data suggest indene is biodegradable. Indene may be susceptible to some direct photolysis in sunlight(5); however, this is not expected to be an important removal process(SRC). Indene is not expected to hydrolyze in the aquatic environments(SRC). Volatilization from water is fast with estimated half-lives of 3.7 hrs and 4.4 days from a model river and model lake, respectively(1,SRC).

ATMOSPHERIC FATE: Based upon a measured vapor pressure of 1.1 mm Hg at 25 °C(1), indene is expected to exist almost entirely in the vapor phase in the ambient atmosphere(2,SRC). Vapor-phase indene will degrade rapidly in the ambient atmosphere by reaction with photochemically produced hydroxyl radicals with an estimated half-life of about 6.2 hours(3,SRC).

Indene was qualitatively identified in effluents from a POTW facility in Sauget, Illinois(1). On October 24, 1974, indene was qualitatively found in advanced waste treatment concentrates from Lake Tahoe, CA(2). During August and September of 1979, indene was found at a concn range of 0.08-0.4 ug/cu-m in the Allegheny Mountain Tunnel in Pennsylvania(3). Indene was identified at a concn range of 10.3-137.6 ng/L in paper-mill effluents being discharged into the Rainy River(4). Indene was identified in a plume of contaminated water moving through sand away from creosote waste disposal lagoons(5). Indene was found at a concn of 1.28 in an air sample taken near an oil fire(6).

Indene was found in a groundwater sample prior to coal gasification (0.03 ppm), process water during gasification (272 and 72 ppm), and aqueous condensate from low-BTU coal gasification (363 ppm)(1). Indene was found at a concn of 15 ng/L in a canal to a harbor of a freshwater lake before any boat traffic was observed; after 1,293 boats passed through the canal, the concn of indene was 74 ng/L(2). Indene has been detected in wastewater effluents from the timber products industry at a concn of 8,252 ng/ul extract(3).

In 1977, indene was qualitatively identified in the air of six industrial cities of the former USSR(1). Indene was qualitatively found in the air of three South African cities during the summer of 1975-winter of 1976(2). Indene was qualitatively identified in air taken at Homebush Bay, Australia on June 3, 1975(3). Indene was qualitatively identified in Paris air on October 24, 1972(4).

BY ANALOGY BETWEEN CHEMICAL STRUCTURE & TOXICOLOGICAL EFFECTS OF RELATED MONOAROMATIC HYDROCARBONS, INHALATION OF INDENE VAPORS CAN BE EXPECTED TO CAUSE IRRITATION OF MUCOUS MEMBRANES.

THERE ARE ... SENSITIZING ACTIONS OF COUMARONE & INDENE, USED IN COPOLYMERIZATION WHEN MAKING COUMARONE-INDENE RESINS. USE OF THESE RESINS CONTAMINATED WITH TRACES OF MONOMERS CAN CAUSE ALLERGIC DERMATITIS.

YIELDS CIS-1,2-DIHYDROXYINDANE & TRANS-1,2-DIHYDROXYINDANE IN RABBITS. /FROM TABLE/

RAT-LIVER MICROSOMES SUPPLEMENTED WITH NADPH CONVERTED INDENE INTO TRANS-INDANE-1,2-DIOL ...

THE OXIDATION OF INDENE TO TRANS-1,2-DIHYDROXYINDANE IN LIVER PREPN IN VITRO WAS DEMONSTRATED. THE REACTION WAS MEDIATED BY LIVER MICROSOMES OF RATS & RABBITS IN THE PRESENCE OF NADPH-GENERATING SYSTEMS.

Used to prepare coumarone-indene resins; [ACGIH]

Plastic Composites Manufacturing [Category: Industry]

Used as a comonomer in coumarone and petroleum-derived aromatic hydrocarbon resins. Technical pure indene is used for the production of indan and its derivatives. Esters of indene-1-carboxylic acid, which are effective as acaricides, can be synthesized from indene for use in, eg, collars

It is composed of a benzene ring fused with a cyclopentene ring.

... FROM ACETYLENE OVER ACTIVATED CHARCOAL @ 625 °C ... MFR FROM TETRAHYDRONAPHTHALENE BY PASSING OVER SIO2-AL2O3 CATALYST @ 670 °C

Pyrolysis residual oils from olefin production contain varying amounts of indene, which can be separated by extractive distillation with N-methyl-2- pyrrolidone or by crystallization. Indene is recovered industrially from dephenolated and debased tar light oil by rectifying distillation followed by crystallization. When the phenol extraction is omitted a highly concentrated indene fraction can also be obtained by azeotropic distillation of an indene- phenol fraction with water, whereby the phenol is separated as a bottom product.

Petrochemical Manufacturing

1H-Indene: ACTIVE