Description
1, 2:5, 6-DIBENZANTHRACENE is a crystalline aromatic hydrocarbon. It is a component of coal tars, shale oils, and soots (IARC, 1985) and has been detected in gasoline engine exhaust, coke oven emissions, cigarette smoke, charcoal broiled meats, vegetation near heavily traveled roads, and surface water and soils near hazardous waste sites. It is a kind of carcinogenic compound, and thus being mainly used for the research purpose. For example, in biological research, it is a mutagen used to induce tumorigenesis.
Chemical Properties
Dibenz(a,h)anthracene is a colorless, crystal-
line solid. PAHs are compounds containing multiple
benzene rings and are also called polynuclear aromatic
hydrocarbons.
Chemical Properties
white to light yellow crystalline solid
Chemical Properties
Dibenz[a,h]anthracene is a white crystalline solid.
It is insoluble in water, slightly soluble in alcohol, and
soluble in ether. This compound is incompatible with strong
oxidizers.
Physical properties
Colorless to pale yellow, monoclinic or orthorhombic crystals which with a faint, pleasant odor.
Uses
There is no report on the common use of dibenz[a,h]anthracene
and its commercial production.
Uses
Dibenz[a,h]anthracene is a polycyclic aromatic hydrocarbon (PAH) and a known carcinogen. Dibenz[a,h]anthracene has produced positive results in bacterial DNA damage and mutagenicity assays and in mammalian cell DNA damage, mutagenicity and cell transformation assays.
Definition
ChEBI: Dibenz[a,h]anthracene is an ortho-fused polycyclic arene. It has a role as a mutagen.
Production Methods
There is no commercial production or known use of this
compound. It has been isolated from the coal tar pitch and
is found in coke over effluents. It has been detected in
urban atmospheres and occurs in tobacco smoke. Dibenz
[a,h]anthracene is present as a minor component of the
total PAH content in the environment. Human exposure
occurs through smoking, inhaling of polluted air, and by
ingesting food and water containing combustion
products.
General Description
White crystals or pale yellow solid. Sublimes.
Air & Water Reactions
Insoluble in water.
Reactivity Profile
1,2:5,6-DIBENZANTHRACENE is incompatible with strong oxidizing agents. Is oxidized by chromic acid and by osmium tetraoxide .
Health Hazard
The toxicity of dibenz[a,h]anthracene is onthe same order as that of benz[a]anthracene.A lethal dose in mice by intravenous routeis 10 mg/kg. There is no report on its oraltoxicity. It is a mutagen. Its carcinogenicityin animals is well established, causing cancersin the lungs, liver, kidney, and skin.
Fire Hazard
Flash point data for 1,2:5,6-DIBENZANTHRACENE are not available; however, 1,2:5,6-DIBENZANTHRACENE is probably combustible.
Safety Profile
Confirmed carcinogen
with experimental carcinogenic,
tumorigenic, and neoplastigenic data. Poison
by intravenous route. Human mutation data
reported. When heated to decomposition it
emits acrid smoke and irritating fumes.
Potential Exposure
Dibenz(a,h)anthracene is a chemical
substance formed during the incomplete burning of fossil
fuel, garbage, or any organic matter and is found in smoke
in general; it condenses on dust particles and is distributed
into water and soil and on crops. DB(a,h)A is a PAH and
is also a component of coal tar pitch, which is used
in industry as a binder for electrodes, and creosote is used
to preserve wood. PAHs are also found in limited amounts
in bituminous materials and asphalt used in industry and
for paving.
First aid
If this chemical gets into the eyes, remove anycontact lenses at once and irrigate immediately for at least15 min, occasionally lifting upper and lower lids. Seek medical attention immediately. If this chemical contacts theskin, remove contaminated clothing and wash immediatelywith soap and water. Seek medical attention immediately. Ifthis chemical has been inhaled, remove from exposure,begin rescue breathing (using universal precautions, including resuscitation mask) if breathing has stopped and CPR ifheart action has stopped. Transfer promptly to a medicalfacility. When this chemical has been swallowed, get medical attention. Give large quantities of water and inducevomiting. Do not make an unconscious person vomit.
Carcinogenicity
Based on no human data and
sufficient data from animal assays, IRIS classifies dibenz
[a,h]anthracene as a B2 carcinogen, a probable human
carcinogen, and the IARC classifies dibenz[a,h]anthracene
as a 2A carcinogen. Dibenz[a,h]anthracene produced
carcinomas in mice following oral or dermal administration
and injection site tumors in several species following s.c.
or i.m. injection. It is also a tumor initiator.
Source
Constituent in coal tar, cigarette smoke (4 μg/1,000 cigarettes), and exhaust condensate of gasoline engine (96 μg/g) (quoted, Verschueren, 1983). Also detected in asphalt fumes at an
average concentration of 12.25 ng/m
3 (Wang et al., 2001).
Based on laboratory analysis of 7 coal tar samples, dibenz[a,h]anthracene was not detected
(EPRI, 1990). Lehmann et al. (1984) reported dibenz[a,h]anthracene concentrations of 0.03 mg/g
and 1,300 mg/kg in a commercial anthracene oil and high-temperature coal tar, respectively.
Identified in a high-temperature coal tar pitch used in roofing operations at concentrations ranging
from 317 TO 1,680 mg/kg (Malaiyandi et al., 1982).
Nine commercially available creosote samples contained dibenz[a,h]anthracene at
concentrations ranging from 1 to 16 mg/kg (Kohler et al., 2000).
Under atmospheric conditions, a low rank coal (0.5–1 mm particle size) from Spain was burned
in a fluidized bed reactor at seven different temperatures (50 °C increments) beginning at 650 °C.
The combustion experiment was also conducted at different amounts of excess oxygen (5 to 40%)
and different flow rates (700 to 1,100 L/h). At 20% excess oxygen and a flow rate of 860 L/h, the
amount of dibenz[a,h]anthracene emitted ranged from 32.0 ng/kg at 900 °C to 260.9 ng/kg at 750
°C. The greatest amount of PAHs emitted were observed at 750 °C (Mastral et al., 1999).
Environmental Fate
Biological. In activated sludge, <0.1% of the applied dibenz[a,h]anthracene mineralized to
carbon dioxide after 5 d (Freitag et al., 1985). Based on aerobic soil die away test data, the
estimated half-lives ranged from 361 to 940 d (Coover and Sims, 1987).
Ye et al. (1996) investigated the ability of Sphingomonas paucimobilis strain U.S. EPA 505 (a
soil bacterium capable of using fluoranthene as a sole source of carbon and energy) to degrade 4,
5, and 6-ringed aromatic hydrocarbons (10 ppm). After 16 h of incubation using a resting cell
suspension, only 7.8% of dibenz[a,h]anthracene had degraded. It was suggested that degradation
occurred via ring cleavage resulting in the formation of polar metabolites and carbon dioxide.
Soil. The reported half-lives for dibenz[a,h]anthracene in a Kidman sandy loam and McLaurin
sandy loam are 361 and 420 d, respectively (Park et al., 1990).
Photolytic. A carbon dioxide yield of 45.3% was achieved when dibenz[a,h]anthracene
adsorbed on silica gel was irradiated with light (λ >290 nm) for 17 h (Freitag et al., 1985). The
photooxidation half-life in the atmosphere was estimated to range from 0.428 to 4.28 h (Atkinson,
1987).
Chemical/Physical. Dibenz[a,h]anthracene will not hydrolyze because it does not contain a
hydrolyzable functional group (Kollig, 1993).
At influent concentrations of 1.0, 0.1, 0.01, and 0.001 mg/L, the GAC adsorption capacities
were 69, 12, 2.1, and 0.39 mg/g, respectively (Dobbs and Cohen, 1980).
storage
Color Code—Blue: Health Hazard/Poison: Storein a secure poison location. See the entry on “Coal TarPitch Volatiles.” A regulated, marked area should be established where this chemical is handled, used, or stored incompliance with OSHA Standard 1910.1045
Shipping
UN2811 Toxic solids, organic, n.o.s., Hazard
Class: 6.1; Labels: 6.1-Poisonous materials, Technical Name
Required. UN3077 Environmentally hazardous substances,
solid, n.o.s., Hazard class: 9; Labels: 9-Miscellaneous
hazardous material, Technical Name Required.
Purification Methods
The yellow-green colour (due to other pentacyclic impurities) is removed from it by crystallising from *benzene or by selective oxidation with lead tetraacetate in acetic acid [Moriconi et al. J Am Chem Soc 82 3441 1960]. [Beilstein 5 IV 2722.]
Toxicity evaluation
Dibenz[a,h]anthracene is largely associated with particulate
matters, soils, and sediments. Its presence in places distant
from primary sources indicates that it is reasonably stable in the
atmosphere and capable of long-distance transport.
Dibenz[a,h]anthracene can be adsorbed very strongly if
released to the soil. However, no leaching to the groundwater
or hydrolization or evaporation from soils surface is expected.With half-lives of 18 and 21 days, it is generally subjected to
biodegradation in soil systems. Volatilization of dibenz[a,h]
anthracene from wet soil surfaces is not expected to be an
important fate process based on an estimated Henry’s Law
constant of 7.3×10
-8 atm-m3 mol
-1. A biodegradation halflife
of 750 days at 20°C after incubation with unacclimated
soil microcosms indicates that biodegradation is not an
important environmental fate process in soil.
Dibenz[a,h]anthracene released to the atmosphere will likely
be associated with particulate matter and may be subjected to
moderately long-range transport, depending mainly on the
particle size distribution and climatic conditions, which will
determine the rates of wet and dry deposition. The estimated
vapor pressure of 9.5×10
10 mm Hg at 25°C of dibenz[a,h]
anthracene indicates that this compound will exist solely in the
particulate phase in the ambient atmosphere if released into
air. Its presence in areas remote from primary sources
demonstrates the potential for this long-range transport as well
as dibenz[a,h]anthracene’s considerable stability in the air.
Dibenz[a,h]anthracene absorbs solar radiation strongly, suggesting
that it may be susceptible to direct photolysis in the
environment. The estimated vapor phase half-life in the
atmosphere is 1 day as a result of reaction with photochemically
produced hydroxyl radicals.
Incompatibilities
Incompatible with oxidizers (chlorates,
nitrates, peroxides, permanganates, perchlorates, chlorine,
bromine, fluorine, etc.); contact may cause fires or explo-
sions. Keep away from alkaline materials, strong bases,
strong acids, oxoacids, and epoxides.
Waste Disposal
See the entry on Coal Tar
Pitch Volatiles. Consult with environmental regulatory
agencies for guidance on acceptable disposal practices.
Generators of waste containing this contaminant (≥100 kg/
mo) must conform with EPA regulations governing storage,
transportation, treatment, and waste disposal.
References
https://pubchem.ncbi.nlm.nih.gov/compound/Dibenz_a_h_anthracene#section=Top
Heidelberger, Charles, and H. B. Jones. "The Distribution of Radioactivity in the Mouse Following Administration of Dibenzanthracene Labeled in the 9 and 10 Positions with Carbon Fourteen." Cancer1.2(2010):252.
https://rais.ornl.gov/tox/profiles/dibenz_a_h_anthracene_c_V1.html
![Dibenz[a,h]anthracene Structure](https://www.chemicalbook.com/CAS/GIF/53-70-3.gif)
