Description
The term “coal tar products,” as used byNIOSH, includes coal tar and two of the fractionation products of coal tar, creosote and coal tar pitch, derived fromthe carbonization of bituminous coal. Coal tar, coal tarpitch, and creosote derived from bituminous coal often contain identifiable components which by themselves are carcinogenic, such as benzo(a)pyrene, benzanthracene, chrysene,and phenanthrene. Other chemicals from coal tar products,such as anthracene, carbazole, fluoranthene, and pyrene,may also cause cancer, but these causal relationships havenot been adequately documented. Also, the research chemical methylcholanthrene [CAS: 56-49-5], a powerful carcinogen, fits this category. Boiling point =＞260℃; Meltingpoint =250-180℃; Flash point =207℃ (coal tar pitch);74℃ (creosote oil); Autoignition temperature =＞510℃.Insoluble in water.
Chemical Properties
A nearly black, viscous liquid. On exposure to air, the viscosity gradually increases. It burns in air with a luminous, sooty flame. It has a weight per mL of about 1.15 g.
Chemical Properties
The term “coal tar products,” as used by NIOSH, includes coal tar and two of the fractionation products of coal tar, creosote and coal tar pitch, derived from the carbonization of bituminous coal. Coal tar, coal tar pitch, and creosote (coal tar creosote 8001-58-9) derived from bituminous coal often contain identifiable components which by themselves are carcinogenic, such as benzo(a) pyrene, benzanthracene, chrysene, and phenanthrene. Other chemicals from coal tar products, such as anthracene, carbazole, fluoranthene, and pyrene may also cause cancer,but these causal relationships have not been adequately documented. Also, the research chemical methylcholanthrene (CAS: 56-49-5), a powerful carcinogen, fits this category. Coal tar pitch is a black viscous liquid. Aromatic solvent odor. Boiling point =>260°C; specific gravity (H2O:1) = 1.07-108; freezing/melting point = 250-°180C;flash point = 207°C (coal tar pitch); 74C (creosote oil);autoignition temperature =>510°C. Insoluble in water.Coal tar creosote (8001-58-9, crosote) is an black oily,tar-like substance. Pungent odor
Uses
Coal tar pitch is used as a base for paints and coatings, as a
binder for carbon electrodes, for impregnating fiber pipe, in
briquetting coal, in foundry core compounds, as a plasticizer
for elastomers and polymers, as extenders, saturants, impregnants,
and sealants, and in paving and roofing. Occupations
with potential exposures to coal tar, coal tar pitch.
Uses
Used in treatment of psoriasis.
Uses
Occur as emissions from
coke ovens, from coking of coal tar pitch, and
from Soderberg aluminum reduction electrolytic
cells; used for base coatings and paints;
for roofing and paving; and as a binder for
carbon electrodes
Definition
Tar produced by heating coal in
the absence of oxygen. It is a mixture of
many organic compounds (e.g. benzene,
toluene, and naphthalene) and also contains
free carbon.
Definition
coal tar: A tar obtained from the destructivedistillation of coal. Formerly,coal tar was obtained as a byproductin manufacturing coal gas.Now it is produced in making cokefor steel making. The crude tar containsa large number of organiccompounds, such as benzene, naphthalene,methylbenzene, phenols,etc., which can be obtained by distillation.The residue is pitch. At onetime coal tar was the major source oforganic chemicals, most of which arenow derived from petroleum andnatural gas.
Hazard
A human carcinogen. Toxic by inhalation.
Combustible.
Health Hazard
Epidemiological evidence suggests
that workers intimately exposed to the
products of combustion or distillation of bituminous
coal are at increased risk of cancer at
many sites, including lungs, kidney, and skin.
The chemical composition and particle
size distribution of coal tar pitch volatiles
(CTPV) from different sources are significant
variables in determining toxicity.
Safety Profile
Confirmed carcinogen
with experimental carcinogenic and
neoplastigenic data by skin contact. When
heated to decomposition it emits acrid
smoke and fumes.
Potential Exposure
The coke-oven plant is the principal source of coal tar. The hot gases and vapors produced during the conversion of coal to coke are collected by means of a scrubber, which condenses the effluent into ammonia, water, crude tar, and other by-products. Crude tar is separated from the remainder of the condensate for refining and may undergo further processing. Employees may be exposed to pitch and creosote in metal and foundry operations; when installing electrical equipment; in construction, railway, utility; and briquette manufacturing.
Veterinary Drugs and Treatments
Use of coal tar containing shampoos in veterinary medicine is somewhat controversial, particularly since all veterinary-labeled products
have been withdrawn from the market. However, coal tar shampoos have been used in dogs for treating greasy dermatoses (seborrhea
oleosa) for many years.
Coal tar possesses keratoplastic, keratolytic, vasoconstrictive, antipruritic and degreasing actions. Coal tar’s mechanism of keratoplastic
(keratoregulating) action is probably secondary to decreasing mitosis and DNA synthesis of basal epidermal cells.
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
The history of coal tar cancers begins with the observations of scrotal cancer in London chimney sweeps by Percivall Pott in 1777. Since that time, a large body of evidence has accumulated demonstrating that workers involved in carbonizing bituminous coal, those handling certain by-products, or those exposed by inhalation of coal tar pitch volatiles are at excess risk of scrotal and other forms of skin, respiratory, and other types of cancer. Coal tar contains many substances that can cause cancer and is a human carcinogen. The toxicity of coal tar may vary with its origin.
storage
Color Code—Blue: Health Hazard/Poison: Storein a secure poison location. Prior to working with thischemical you should be trained on its proper handling andstorage. Before entering confined space where this chemicalmay be present, check to make sure that an explosive concentration does not exist. Store in tightly closed containersin a cool, well-ventilated area away from strong oxidizers(such as chlorine, bromine, and fluorine). Sources of ignition, such as smoking and open flames, are prohibitedwhere coal tar creosote is used, handled, or stored in a manner that could create a potential fire or explosion hazard.Metal containers involving the transfer of 5 gallons or moreof coal tar creosote should be grounded and bonded. Drumsmust be equipped with self-closing valves, pressure vacuumbungs, and flame arresters. A regulated, marked area shouldbe established where this chemical is handled, used, orstored in compliance with OSHA Standard 1910.1045.Entry into areas containing coal tar creosote is to be controlled by permit only.
Shipping
UN1136 Coal tar distillates, flammable, Hazard Class: 3; Labels: 3-Flammable liquid
Incompatibilities
Incompatible with strong oxidizers (chlorates, nitrates, peroxides, permanganates, perchlorates, chlorine, bromine, fluorine, etc.); contact may cause fires or explosions. Keep away from alkaline materials, strong bases, strong acids, oxoacids, epoxides. Phenols, such as creosote react as weak organic acids. Phenols and cresols are much weaker as acids than common carboxylic acids (phenol has pKa = 9.88). These materials are incompatible with strong reducing agents such as hydrides, nitrides, alkali metals, and sulfides. Flammable hydrogen gas is often generated, and the heat of the reaction may ignite the gas. Heat is also generated by the acid-base reaction between phenols and bases. Such heating may initiate polymerization of the organic compound. Phenols are sulfonated very readily (e.g., by concentrated sulfuric acid at room temperature). The reactions generate heat. Phenols are also nitrated very rapidly, even by dilute nitric acid
Waste Disposal
Dissolve or mix the material with a combustible solvent and burn in a chemical incinerator equipped with an afterburner and scrubber. All federal, state, and local environmental regulations must be observed.
