Pentachlorobenzene

Pesticide -> EPA IRIS

Pesticide (Pentachlorobenzene (PCB)) -> USDA PDB

log Kow = 5.18

5.03/5.63

5.2

1.8342 (NTP, 1992) - Denser than water; will sink

1.8342 at 16.5 °C

Liquid density: 1.609 g/cu cm at 84 °C

Relative density (water = 1): 1.8

1.8342 @ 16°C

Colorless needles

White crystalline solid

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

In water, 0.831 mg/L at 25 °C

In water, 0.18 to 1.34 mg/L at 22-25 °C

Insoluble in ethanol; slightly soluble in ether, benzene, chloroform and carbon disulfide

Solubility in water: none

531 °F at 760 mmHg (NTP, 1992)

277 °C

275-277 °C

277 °C @760 [mm Hg]

When heated to decomp it emits ... fumes of /hydrogen chloride/.

Some organic chlorides decompose to yield phosgene. /Chlorides/

187 °F (NTP, 1992)

86 °C

86 °C

86 °C

Danger

H228: Flammable solid [Danger Flammable solids]

P210, P240, P241, P264, P270, P273, P280, P301+P317, P330, P370+P378, P391, and P501 (click each P-code to see the statement)

Danger

H228 (100%): Flammable solid [Danger Flammable solids]

P210, P240, P241, P264, P270, P273, P280, P301+P317, P330, P370+P378, P391, and P501 (click each P-code to see the statement)

Hazard Traits - Bioaccumulation; Environmental Persistence; Environmental tox

S - indicates a substance that is identified in a final Significant New Use Rule.

Substance: Pentachlorobenzene

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.)

Flash point data for this compound are not available but it is probably non-flammable. (NTP, 1992)

Combustible under specific conditions. Gives off irritating or toxic fumes (or gases) in a fire.

USEPA; Ambient Water Quality Criteria Doc: Dichlorobenzenes (1980) EPA 440/5-80-039

USEPA; Ambient Water Quality Criteria Doc: Chlorinated Benzenes (1980) EPA 440/5-80-028

USEPA; Health Assessment Document: Chlorinated Benzenes (1985) EPA-600/8-84-015

DHHS/NTP; NTP Report on the Toxicity Studies of Pentachlorobenzene in F344/N Rats and B6C3F1 Mice (Feed Studies) NTP TOX 6 (1991) NIH Pub No. 91-3125

U183; As stipulated in 40 CFR 261.33, when pentachlorobenzene, as a commercial chemical product or manufacturing chemical intermediate or an off-specification commercial chemical product or a manufacturing chemical intermediate, becomes a waste, it must be managed according to Federal and/or State hazardous waste regulations. Also defined as a hazardous waste is any residue, contaminated soil, water, or other debris resulting from the cleanup of a spill, into water or on dry land, of this waste. Generators of small quantities of this waste may qualify for partial exclusion from hazardous waste regulations (40 CFR 261.5).

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. Pentachlorobenzene is included on this list. Effective date: 10/4/82; Sunset date: 10/4/92.

A fire in your laboratory involving this chemical should be extinguished with a dry chemical, carbon dioxide or halon extinguisher. (NTP, 1992)

Use water spray, powder, foam, carbon dioxide.

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. Refer for medical attention .

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.

Suitable extinguishing media: Use water spray, alcohol-resistant foam, dry chemical or carbon dioxide. Special protective equipment for fire-fighters: Wear self contained breathing apparatus for fire fighting if necessary.

Use water spray, powder, foam, carbon dioxide.

Use water spray to cool unopened containers.

Keep container tightly closed in a dry and well-ventilated place.

Provision to contain effluent from fire extinguishing.

Personal precautions: Use personal protective equipment. Avoid dust formation. Avoid breathing vapors, mist or gas. Ensure adequate ventilation. Remove all sources of ignition. Evacuate personnel to safe areas. Avoid breathing dust. Environmental precautions: Prevent further leakage or spillage if safe to do so. Do not let product enter drains. Discharge into the environment must be avoided. Methods and materials for containment and cleaning up: Sweep up and shovel. Contain spillage, and then collect with an electrically protected vacuum cleaner or by wetbrushing and place in container for disposal according to local regulations. Keep in suitable, closed containers for disposal. Contain spillage, pick up with an electrically protected vacuum cleaner or by wet-brushing and transfer to a container for disposal according to local regulations.

Personal protection: P2 filter respirator for harmful particles. Do NOT let this chemical enter the environment. Sweep spilled substance into covered sealable containers. If appropriate, moisten first to prevent dusting. Carefully collect remainder. Then store and dispose of according to local regulations.

SMALL SPILLS AND LEAKAGE: If a spill of this chemical occurs, FIRST REMOVE ALL SOURCES OF IGNITION, then you should dampen the solid spill material with acetone and transfer the dampened material to a suitable container. Use absorbent paper dampened with acetone to pick up any remaining material. Seal your contaminated clothing and the absorbent paper in a vapor-tight plastic bag for eventual disposal. Solvent wash all contaminated surfaces with acetone followed by washing with a soap and water solution. Do not reenter the contaminated area until the Safety Officer (or other responsible person) has verified that the area has been properly cleaned.

Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number U183, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.

Potential candidate for rotary kiln incineration, with temperature range of 820 to 1,600 °C, and a residence time of hours.

Personal protection: P2 filter respirator for harmful particles. Do NOT let this chemical enter the environment. Sweep spilled substance into covered sealable containers. If appropriate, moisten first to prevent dusting. Carefully collect remainder. Then store and dispose of according to local regulations.

SRP: Local exhaust ventilation should be applied wherever there is an incidence of point source emissions or dispersion of regulated contaminants in the work area. Ventilation control of the contaminant as close to its point of generation is both the most economical and safest method to minimize personnel exposure to airborne contaminants. Ensure that the local ventilation moves the contaminant away from the worker.

Do not eat, drink, or smoke during work.

Avoid contact with skin and eyes. Avoid formation of dust and aerosols. Provide appropriate exhaust ventilation at places where dust is formed. Keep away from sources of ignition - No smoking. Take measures to prevent the build up of electrostatic charge.

Handle in accordance with good industrial hygiene and safety practice. Wash hands before breaks and at the end of workday.

Pentachlorobenzene concentrations were reported as follows: Slovenia Province, Yugoslavia: human adipose tissue, 1979-80, 15 samples, not detected to 3 ppb, 1.2 ppb average (fat basis), human milk, 1981, 12 samples, 18 ppb (fat basis)(1); human milk, 6 samples, 0-3.4 ppb, 2.0 ppb average, 2 whole milk(2). In an analysis of human adipose autopsy samples from six municipalities in Ontario, Canada, pentachlorobenzene was qualitatively detected (1.9 ppb detection limit) as follows(3): Cornwall, 4% of 21 patients; London, 3% of 37 patients; St. Catherines, 12% of 17 patients; Windsor, 14% of 36 patients; Toronto, 0% of 7 patients; Welland, 0% of 7 patients(3). Pentachlorobenzene was not detected in the tissue of 7 patients from Toronto or 23 patients from Welland(4).

Pentachlorobenzene /was found/ at /a concentration of/ 0.009 ppm in samples of human adipose tissue in Japan.

A survey of human milk from the general and indigenous (Canadian Indian and Inuit mothers) population of Canada found pentachlorobenzene residues in 17% of the 18 indigenous population samples at an avg concn of positive samples of 2 ppb (milkfat basis) and trace levels (whole milk basis) and in 97% of the general population samples (number of samples not reported) at an average concentration of positive samples of 3 ppb (milkfat basis) and 0.1 ppb (whole milk basis)(1).

LC50; Species: /Lepomis macrochirus/ (Bluegill sunfish); Concentration: 2.27 mg/L for 24 hr; 0.55 mg/L for 48 hr; 0.25 mg/L for 96 hr /Conditions of bioassay not specified/

LC50; Species: /Cyprinidon variegatus/ (Sheepshead minnow); Concentration: >32.0 mg/L for 24 hr; 9.55 mg/L for 48 hr; 0.83 mg/L for 96 hr /Conditions of bioassay not specified/

LC50; Species: Poecilia reticulata (guppy); Concentration: 0.178 ppm for 14 days /Conditions of bioassay not specified/

EC50; Species: Pseudokirchneriella subcapitata (Green Algae); Conditions: freshwater, static; Concentration: 32000 ug/L for 24 hr; Effect: population, chlorophyll A concentration /formulation/

For more Ecotoxicity Values (Complete) data for PENTACHLOROBENZENE (9 total), please visit the HSDB record page.

TERRESTRIAL FATE: Based on a classification scheme(1), an experimentally-derived Koc range of 3162 to 5.24X10+6(2-4), indicates that pentachlorobenzene is expected to have slight to no mobility in soil(SRC). Volatilization of pentachlorobenzene from moist soil surfaces may be an important fate process(SRC) given a Henry's Law constant of 7.03X10-4 atm-cu m/mole at 25 °C(5), however, strong adsorption to soil will attenuate the importance of volatilization(SRC). Pentachlorobenzene is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 0.002 mm Hg at 25 °C(6). Pentachlorobenzene was shown to be resistant to degradation in laboratory soil tests with half-lives of 194 and 345 days reported in duplicate experiments(7). Pentachlorobenzene is resistant to biodegradation under aerobic conditions(8). Anaerobic biodegradation in soil and sediments yields lower chlorinated benzenes, but the rate can be highly variable(8). Higher organic matter contents seem to drastically increase the persistency(8); the true field half life of pentachlorobenzene is estimated around 6 years in organic soil and sediment in the temperate zone(8).

AQUATIC FATE: Based on a classification scheme(1), an experimentally-derived Koc range of 3162 to 5.24X10+6(2-4), indicates that pentachlorobenzene is expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(5) based upon a Henry's Law constant of 7.03X10-4 atm-cu m/mole(6), but adsorption may attenuate this process(SRC). Using this Henry's Law constant and an estimation method(5), volatilization half-lives for a model river and model lake are 6.6 hours and 6.9 days, respectively, when adsorption is ignored(SRC). The volatilization half-life from a model pond is about 11 months when adsorption is considered(7,SRC). According to a lassification scheme(8), a BCF range 1085 to 20,000(9), suggests that bioconcentration in aquatic organisms is very high(SRC). Pentachlorobenzene may be susceptible to direct photolysis from surface water. When irradiated with light >290 nm in water, it resulted in 41% photodegradation after 24 hrs(10). Pentachlorobenzene is resistant to biodegradation in sediments under aerobic conditions(9). In anaerobic sediment-water slurries pentachlorobenzene is considered persistent, with a possible exception at temperatures above 10 °C in combination with low organic matter contents(9). Hydrolysis is not expected to be an important environmental fate process since this compound lacks functional groups that hydrolyze under environmental conditions(5).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), pentachlorobenzene, which has a vapor pressure of 0.002 mm Hg at 25 °C(2), is expected to exist almost entirely in the vapor phase in the ambient atmosphere. Vapor-phase pentachlorobenzene is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC); the half-life for this reaction in air is estimated to be about 277 days(SRC) from its estimated rate constant of 5.8X10-14 cu cm/mole-sec(3). Pentachlorobenzene absorbs UV light >290 nm(4), therefore, pentachlorobenzene may be susceptible to direct photolysis by sunlight(SRC). Although pentachlorobenzene is expected to exist primarily in the vapor-phase in the atmosphere, it has been detected in atmospheric dust that settles to the ground via dry deposition(5). Pentachlorobenzene has also been measured in rain and snow precipitation samples(6) which indicates it can be removed from air via wet deposition(SRC). Monitoring data indicate that pentachlorobenzene is subject to long range transport(6).

Pentachlorobenzene was detected in 20 of 1,500 composite foods in the US with a daily intake of 0.3 ug in 1975 and in 12 of 1,500 composite food samples in the US with a daily intake of 0.03 ug in 1976(1). In 1976-1977 pentachlorobenzene was detected in 15 of 300 composite food samples in the US at trace concentrations to 0.003 ppm(2) and in 1977-1978 was detected in 22 of 240 composite food samples at concentrations of trace amounts to 0.005 ppm(3). Pentachlorobenzene was detected in 3 of 117 infant food samples at concentrations of trace amounts to 0.005 ppm and in 10 of 132 toddler food composites at concentrations of trace amounts to 0.010 ppm(4). Pentachlorobenzene was detected in 4 of 98 infant food samples at concentrations of 0.002-0.012 ppm and in 13 of 110 toddler food composites at concentrations of trace amounts to 0.008 ppm(5). Pentachlorobenzene has been found in the following crude seed oils: Yugoslavian corn oil (0.010 ppm), rape seed oil (0.001 ppm), sunflower oil (0.005 ppm), walnut oil (0.005 ppm), and poppy oil (0.005 ppm); US soybean oil (trace concentration); Chinese peanut oil (0.005 ppm) and sesame seed oil (trace concentration); Turkish hazelnut oil (0.001 ppm)(6).

Pentachlorobenzene was detected in 2 percent of all food products sampled in the US between 1982-1984 and 1 percent of food products sampled between 1984-1986(1). Pentachlorobenzene was detected in 15 of 230 ready to eat foods in the US at an average concentration of 0.0012 ug/g(2).

Pentachlorobenzene was detected in 15 of 20 composite samples of fats and oils at a range of trace levels to 0.003 ppm(1), 1 of 20 composite samples of meat, fish and poultry at trace levels, 1 of 20 composite samples of grain and cereal at a concn of 0.002 ppm and in 1 of 20 composite samples of potatoes at 0.008 ppm obtained from 20 US cities(1). Pentachlorobenzene was detected in 9 of 20 composite samples of fats and oils at a concentration range of trace levels to 0.019 ppm and in 2 of 20 composite samples of sugars and sugar adjuncts at trace levels and 0.001 ppm in 20 US cities(2). Pentachlorobenzene was detected in 21 of 27 composite samples of fats and oils at a range of trace levels to 0.004 ppm, in 1 of 27 composite samples of root vegetables at trace levels and in 2 of 27 composite samples of sugars and sugar adjuncts at trace levels collected in 27 US cities(3).

... in peanut butter samples: avg: 16 ppb, range: 1.8-62 ppb ...

ENVIRONMENTAL: A survey of human milk from the general population of Canada found pentachlorobenzene residues in 17 percent of the samples at an average concentration of 2 ppb(1). Chlorobenzenes (including pentachlorobenzene) were detected in human milk at trace concentrations to 25 ug/kg(2). Pentachlorobenzene was detected in whole milk (0.05 ng/g) and milk fat (1.5 ng/g) in Canada(3). Human milk samples collected from 38 breast-feeding mothers between December 2005 and February 2006 from Chelem in Yucatan, Mexico contained a mean pentachlorobenzene level of 178.86 ng/g(4).

The Mean Daily Intake of pentachlorobenzene in the US from 1984-1986 was 0.003 ug/kg (6-11 months old), 0.0014 ug/kg (2 years old), 0.0003 ug/kg (14-16 years old, female), 0.0005 ug/kg (14-16 years old, male), 0.0002 ug/kg (25-30 years old, female), 0.0004 ug/kg (25-30 years old, male), 0.0002 ug/kg (60-65 years old, female) and 0.0002 ug/kg (60-65 years old, male)(1).

/AQUATIC SPECIES/ The growth rate reduction of mosquito fish (Gambusia affinis) fry was investigated with a range of sublethal exposure levels of four halobenzenes for 42 days. These compounds were found to produce growth rate reduction in mosquito fish fry at concentrations as low as 0.30, 0.18, 0.025, and 0.010 umol/L for 1,4-dibromobenzene, 1,2,3-trichlorobenzene, 1,2,4-tribromobenzene, and pentachlorobenzene, respectively. The aqueous exposure concentrations causing growth rate reduction of 50 and 10% (EC50 and EC10, respectively) for the halobenzenes were 0.067-3.4 and 0.0042-0.32 umol/L, respectively. The EC50 and LC10 values are within the ranges of 5 to 8% and 0.1 to 3.9% of the LC50 values, respectively. The percentage of growth rate reduction relative to the LC, could possibly be used to describe chronic toxicity effects of organic compounds with the aquatic organisms. The internal concentrations obtained from the analysis for the halobenzenes were generally consistent with the calculated internal concentrations. The lipid-based internal concentrations that gave 50 and 10% growth rate reductions were 8.3-27 and 0.5-1.6 mmol/kg, respectively. These values have a more limited range than the corresponding external aqueous concentrations. The quantitative structure-activity relationships between the internal concentrations at 50 and 10% growth rate reduction and physicochemical parameters were found to be less satisfactory than those based on external aqueous concentrations.

Pentachlorobenzene was found in most samples taken from eggs of herring gulls (Larus argentatus) and double-crested cormorants (Phalacrocorax auritus). The eggs from the Maritime provinces had less chlorinated benzenes than similar samples from Lake Ontario.

Pentachlorobenzene was detected at mean concentrations of 2 ng/g (males) and 3 ng/g (females) in the blubber of beluga whales (Delphinapterus leucas) in the St Lawrence River estuary(1). Pentachlorobenzene was detected in the eggs of seabirds in Canada at concentrations of 0.011 and 0.007 mg/kg(2) and the eggs of robins (Turdus migratorius) at concentrations of 0-0.9 ug/g(3). Pentachlorobenzene was detected in the eggs of herring gulls (Largus agrentatus) in Ontario, Canada at concentrations of 6-95 ng/g(4) and various bird eggs from Hamilton Harbor, Canada at concentrations of 0.002-0.02 mg/kg(5). Pentachlorobenzene was detected in 37 percent of the pheasants (Phasianus colchicus) sampled from Kansas at concentrations of trace levels to 6 ppb(6). Mean concentrations from animal samples from the White Sea, Russia: seal blubber: 0.9 ng/g to 12 ng/g lipid; spider crab: 0.08 ng/g wet wt; zooplankton: 0.07 ng/g wet wt. Pentachlorobenzene concentrations of 0.05 ng/g were reported from Antarctic krill and 0.68 ng/g for Adelie penguine eggs. Polar bear adipose tissue collected between 1996 and 2002 contained pentachlorobenzene plus tetrachlorobenzene levels of 14.6 to 41 ng/g lipid basis(7).

U183; As stipulated in 40 CFR 261.33, when pentachlorobenzene, as a commercial chemical product or manufacturing chemical intermediate or an off-specification commercial chemical product or a manufacturing chemical intermediate, becomes a waste, it must be managed according to Federal and/or State hazardous waste regulations. Also defined as a hazardous waste is any residue, contaminated soil, water, or other debris resulting from the cleanup of a spill, into water or on dry land, of this waste. Generators of small quantities of this waste may qualify for partial exclusion from hazardous waste regulations (40 CFR 261.5).

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. Pentachlorobenzene is included on this list. Effective date: 10/4/82; Sunset date: 10/4/92.

Persons in charge of vessels or facilities are required to notify the National Response Center (NRC) immediately, when there is a release of this designated hazardous substance, in an amount equal to or greater than its reportable quantity of 10 lb or 4.54 kg. The toll free number of the NRC is (800) 424-8802. The rule for determining when notification is required is stated in 40 CFR 302.4 (section IV. D.3.b).

(AZ) ARIZONA 6 ug/l

(FL) FLORIDA 5.6 ug/l

The biliary excretion of metabolites of hexachlorobenzene was studied in rats dosed intragastrically with (14)c-hexachlorobenzene. By GLC-mass spectrometry, 1.8% of the (14)C excreted in the 24 hour bile was shown to be due to pentachlorobenzene.

Pentachlorobenzene is a metabolite of hexachlorobenzene in chick embryo liver cell primary culture.

Pentachlorobenzene yields chlorobenzene in rabbit. From table/

When pentachlorobenzene was added to culture of mold, degradation produced following metabolites: pentachlorophenol, 2,3,4,5- & 2,3,4,6-tetrachlorophenol; 1,2,3,4-tetrachlorobenzene; 1,2,4,5- &/or 1,2,3,5-tetrachlorobenzene; 2,3,4-, 2,4,6- & 3,4,5-trichlorophenol; & 1,3,5-trichlorobenzene.

For more Metabolism/Metabolites (Complete) data for PENTACHLOROBENZENE (8 total), please visit the HSDB record page.

Pentachlorobenzene has known human metabolites that include Pentachlorophenol.

Chemicals that kill or inhibit the growth of fungi in agricultural applications, on wood, plastics, or other materials, in swimming pools, etc.

Pesticides designed to control insects that are harmful to man. The insects may be directly harmful, as those acting as disease vectors, or indirectly harmful, as destroyers of crops, food products, or textile fabrics.

... Pentachlorobenzene ... accumulated to appreciable extent in both maternal & fetal tissues /after daily oral administration of 50, 100 & 200 mg/kg to rats on days 6-15 of gestation or 22-day-old fetuses/.

The mean levels of chlorobenzenes (including pentachlorobenzene) in human milk and adipose tissue were determined and ranged from traces to 25 ug/kg for human milk and from not detected to 146 ug/kg for adipose tissue. The distribution of different chlorobenzene isomers in adipose tissue and milk was different.

Single oral doses of 0.5 mg/kg of (14)c-pentachlorobenzene were given to male and female rhesus monkeys. The chemical was readily absorbed and evidence indicates that the lymphatic system was involved in the absorption process. The major excretory pathway was via the feces. It is suggested that the metabolic system involved some mechanism other than the hepatic cytochrome p450. It is suggested that two different hydroxylation pathways could be involved. The first calls for oxidation of the pentachlorobenzene to pentachlorophenol, aND the 2ND calls for nucleophilic displacement reactions of pentachlorobenzene to tetrachlorophenols in sites which are metabolically active, other than the liver.

The reported data are part of a continuing monitoring program of chlorinated hydrocarbons in adipose tissue of canadians in order to monitor disappearance of restricted organochlorine pesticides as well as the appearance of new environmental contaminants. Human adipose tissues were obtained during autopsies on accident victims. Pentachlorobenzene was found in all tissues sampled, regardless of geographic region, age, or sex of the subject. Amounts recovered were erratic, however, making quantitative determinations invalid.

For more Absorption, Distribution and Excretion (Complete) data for PENTACHLOROBENZENE (8 total), please visit the HSDB record page.

Used as a chemical intermediate for pentachloronitrobenzene; [HSDB]

Chemical intermediate for pentachloronitrobenzene

Pentachlorobenzene is not known to have any commercial uses at present. In the past, pentachlorobenzene was one component of a chlorobenzenes mixture used to reduce the viscosity of PCB /polychlorinated biphenyl/ products employed for heat transfer. Pentachlorobenzene has also been used in a chlorobenzenes mixture with PCBs in electrical equipment. Pentachlorobenzene was used in the past as an intermediate in manufacture of pentachloronitrobenzene (quintozene), however, quintozene is now made by chlorination of nitrobenzene. Pentachlorobenzene may also have been used in the past as a fungicide and flame retardant.

Formerly used as a dye carrier

Chlorination of benzene gives a mixture of tetra-, penta-, and hexachlorobenzenes, from which pentachlorobenzene can be isolated by combined distillation and crystallization steps.

When BHC /benzene hexachloride/ is chlorinated in carbon tetrachloride, various substitution derivatives are formed. By use of liquid chlorine, higher substituted derivatives can be obtained. BHC vapor in a mixture with oxygen (air) and chlorine at 470 °C in the presence of a catalyst containing alumina, copper chloride, and potassium chloride yields a mixture of hexachlorobenzene and pentachlorobenzene.

Benzene, 1,2,3,4,5-pentachloro-: ACTIVE

Technical grade PCNB /pentachloronitrobenzene/ contains ... less than 0.1% pentachlorobenzene ...