Benzo[e]pyrene

Preparation

Under nitrogen protection, a vinyl magnesium bromide solution was added dropwise to a tetrahydrofuran solution containing pyrene-4,5-dione at room temperature, and the reaction was stirred for 2 hours. Excess Grignard reagent was quenched with saturated ammonium chloride solution to obtain 4,5-dihydroxy-4,5-divinyl-4,5-dihydropyrene. 4,5-dihydroxy-4,5-divinyl-4,5-dihydropyrene was dissolved in pyridine, phosphorus oxychloride was added, and the mixture was refluxed for 10 minutes to ensure complete cyclization and dehydration.

Chemical Properties

yellow to yellow-green crystalline powder

Physical properties

Crystalline, solid, prisms, or plates. Benzo[e]pyrene is sensitive to ultraviolet light and may degrade into diones.

Uses

Used for studies of immune suppressive activity of bezo[e]Pyrene on antibody response to DNP-Ficoll and sheep erythrocytes and "dispersive liquid -liquid micro extraction” technique by extracting organic compounds from water samples.

Definition

ChEBI: An ortho- and peri-fused polycyclic arene consisting of five fused benzene rings. It is listed as a Group 3 carcinogen by the IARC.

General Description

Colorless crystals or white crystalline solid.

Air & Water Reactions

Insoluble in water.

Reactivity Profile

BENZO[E]PYRENE may be sensitive to prolonged exposure to light.

Health Hazard

There is very little information available onits toxicity. The oral toxicity is expected to below. Its carcinogenic potential is lower thanthat of benz[a]pyrene. Animal studies gaveinconclusive results. Oral administration mayproduce tumors in the stomach. However, theevidence of carcinogenicity of this compoundin animals is inadequate. Benz[e]pyrene isa mutagen, testing positive to the histidinereversion–Ames test and in vitro unscheduled DNA synthesis (UDS)–human fibroblast.

Fire Hazard

Flash point data for BENZO[E]PYRENE are not available. BENZO[E]PYRENE is probably combustible.

Safety Profile

For occupational chemicalanalysis use NIOSH: Polynuclear Aromatic Hydrocarbons(HPLC), 5506; (GC), 5515.

Source

The concentration of benzo[e]pyrene in coal tar and the maximum concentration reported in groundwater at a mid-Atlantic coal tar site were 3,700 and 0.0034 mg/L, respectively (Mackay and Gschwend, 2001). Detected in 8 diesel fuels at concentrations ranging from 0.047 to 2.1 mg/L with a mean value of 0.113 mg/L (Westerholm and Li, 1994). Identified in Kuwait and South Louisiana crude oils at concentrations of 0.5 and 2.5 ppm, respectively (Pancirov and Brown, 1975).
Benzo[e]pyrene is produced from the combustion of tobacco and petroleum fuels. It also occurs in low octane gasoline (0.18–0.87 mg/kg), high octane gasoline (0.45–1.82 mg/kg), used motor oil (92.2–278.4 mg/kg), asphalt (≤0.0052 wt %), coal tar pitch (≤0.70 wt %), cigarette smoke (3 μg/1,000 cigarettes), and gasoline exhaust (quoted, Verschueren, 1983). Lehmann et al. (1984) reported a benzo[e]pyrene concentration of 0.02 mg/g in a commercial anthracene oil.
Schauer et al. (2001) measured organic compound emission rates for volatile organic compounds, gas-phase semi-volatile organic compounds, and particle phase organic compounds from the residential (fireplace) combustion of pine, oak, and eucalyptus. The particle-phase emission rates of benzo[e]pyrene were 0.459 mg/kg of pine burned, 0.231 mg/kg of oak burned, and 0.212 mg/kg of eucalyptus burned.
Particle-phase tailpipe emission rates from gasoline-powered automobiles with and without catalytic converters were 0.015 and 38.2 μg/km, respectively (Schauer et al., 2002).

Environmental Fate

Photolytic. Schwarz and Wasik (1976) reported a fluorescence quantum yield of ≈ 0.3 for benzo[e]pyrene in water.
Chemical/Physical. Benzo[e]pyrene will not hydrolyze because it has no hydrolyzable functional group.

Purification Methods

Purify it by passage through an Al2O3 column (Woelm, basic, activity I) and elute with *C6H6 and recrystallise from 2 volumes of EtOH/*C6H6 (4:1). It forms colourless or light yellow prisms or needles. [Campbell J Chem Soc 3659 1954, Buchta & Kr.ger Justus Liebigs Ann Chem 705 190 1967.] The 1,3,5-trinitrobenzene complex has m 253-254o (orange needles from EtOH), the picrate prepared by mixing 20mg in 1mL of *C6H6 with 20mg of picric acid in 2mL *C6H6, collecting the deep red crystals, and recrystallising from *C6H6 has m 228-229o [NMR: Cobb & Memory J Chem Phys 47 2020 1967]. [Beilstein 5 III 2520, 5 I V 2689.] CARCINOGEN.

Toxics Screening Level

The initial threshold screening level (ITSL) is 0.002 μg/m3 (annual averaging time) for benzo(e)pyrene.