106-46-7

A white colored liquid with the odor of moth balls. Denser than water and insoluble in water. Flash point below 200°F. Used as a moth repellent, to make other chemicals, as a fumigant, and for many other uses.

P-DICHLOROBENZENE(106-46-7) is incompatible with oxidizing agents. P-DICHLOROBENZENE(106-46-7) is also incompatible with aluminum and its alloys. P-DICHLOROBENZENE(106-46-7) liquefies when mixed with camphor, phenol and salol. P-DICHLOROBENZENE(106-46-7) will attack some forms of plastics, rubber and coatings. .

Insoluble in water.

INHALATION: irritation of upper respiratory tract; over-exposure may cause depression and injury to liver and kidney. EYE CONTACT: pain and mild irritation.

The major uses of o-DCB are as a process solvent in the manufacturing of toluene diisocyanate and as an intermediate in the synthesis of dyestuffs, herbicides, and degreasers. p-Dichlorbenzene is used primarily as a moth repellant, a mildew control agent; space deodorant; and in insecticides, which accounts for 90% of the total production of this isomer. Information is not available concerning the production and use of m-DCB. However, it may occur as a contaminant of o-or p-DCB formulations. Both o-and p-isomers are produced almost entirely as by-products during the production of monochlorobenzene

Special Hazards of Combustion Products: Vapors are irritating. Toxic chlorine, hydrogen chloride, and phosgene gases may be generated in fires.

If this chemical gets into the eyes, remove any contact lenses at once and irrigate immediately for at least 15 minutes, occasionally lifting upper and lower lids. Seek medical attention immediately. If this chemical contacts the skin, remove contaminated clothing and wash immediately with soap and water. Seek medical attention immediately. If this chemical has been inhaled, remove from exposure, begin rescue breathing (using universal precautions, including resuscitation mask) if breathing has stopped and CPR if heart action has stopped. Transfer promptly to a medical facility. When this chemical has been swallowed, get medical attention. Give large quantities of water and induce vomiting. Do not make an unconscious person vomit

m-DCB: UN2810 Toxic liquids, organic, n.o.s., Hazard Class: 6.1; Labels: 6.1-Poisonous materials, Technical Name Required. United States DOT Regulated Marine Pollutant. UN3077 Environmentally hazardous substances, solis, n.o.s., Hazard class: 9; Labels: 9-Miscellaneous hazardous material, Technical NameRequired. UN3082 Environmentally hazardous substances, liquid, n.o.s., Hazard class: 9; Labels: 9-Miscellaneous hazardous material, Technical Name Required

For o-DCB and m-DCB: acid fumes, chlorides, strong oxidizers; hot aluminum, or aluminum alloys. For p-DCB: Strong oxidizers; although, incompatibilities for this chemical may also include other materials listed for o-DCB.

Paradichlorobenzene, or PDB, also commonly known as mothballs, are white, volatile crystals with a penetrating odor. Boiling point is 345°F (173°C), flash point is 150°F (65.6°C), and the melting point is 127°F (52°C). PDB is insoluble in water and has a specific gravity of 1.5, which is heavier than water. Vapor density is 5.1, which is heavier than air. In addition to being flammable, it is also toxic by ingestion and an irritant to the eyes, with a TLV of 75 ppm in air. The four-digit UN identification number is 1592. The NFPA 704 designation for PDB is health 2, flammability 2, and reactivity 0. The primary uses are as a moth repellent, a general insecticide, a soil fumigant, and in dyes.

colourless or white crystals

There are three isomeric forms of dichlorobenzene (DCB): m-DCB is a flammable liquid and vapor.

Incineration, preferably after mixing with another combustible fuel. Care must be exercised to assure complete combustion to prevent the formation of phosgene. An acid scrubber is necessary to remove the halo acids produced. 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

Colorless to white crystals with a penetrating, sweet, mothball or almond-like odor. At 40 °C, the average odor threshold concentration and the lowest concentration at which an odor was detected were 18 and 4.5 μg/L, respectively. Similarly, at 25 °C, the average taste threshold concentration and the lowest concentration at which a taste was detected were 32 and 11 μg/L, respectively (Young et al., 1996). A detection odor threshold concentration of 73 μg/m³ (121 ppb_v) was reported by Punter (1983).

1,4-Dichlorobenzene is used as a fumigantand as an insecticide. For domestic use against clothes moths; as space deodorant in room deodorizers, toilet bowl blocks and diaper pail deodorizers. Intermediate in production of plastics for electronic components.

1,4-Dichlorobenzene is used as a fumigantand as an insecticide.

Insecticidal fumigant. For domestic use against clothes moths; as space deodorant in room deodorizers, toilet bowl blocks and diaper pail deodorizers. Intermediate in production of plastics for electronic components.

The compound 1,4-dichlorobenzene is most commonly referred to as para-DCB or p-DCB. It is widely used as a moth killer, in space deodorizers, and in the production of polyphenylene sulfide. It is also used in the manufacture of certain resins, in the pharmaceutical industry, and as a general insecticide in farming. At room temperature, 1,4- dichlorobenzene is a white or colorless crystalline solid with a characteristic penetrating odor. When exposed to air, it is slowly transformed from its solid state into a vapor; the released vapor then acts as a deodorizer and insect killer. It is practically insoluble in water and is soluble in alcohol, acetone, ether, chloroform, carbon disulfide, and benzene. Its chemical formula is C₆H₄Cl₂.
There is limited evidence that 1,4-dichlorobenzene can damage a developing fetus. Exposure can damage the lungs, liver, kidneys, and blood cells, causing anemia; it can also cause swelling of the eyes, hands, and feet. It can damage the nervous system, causing weakness, trembling, and numbness in the arms and legs. It may cause a skin allergy, which when developed can cause itching and a skin rash. Higher levels of the chemical in air, such as the levels that are sometimes associated with industrial exposure, can cause headaches, nausea, clumsiness, slurred speech, and dizziness. Levels that would result in death would be associated with an odor so intense that it would be very unpleasant, if not intolerable, and would serve as a danger warning. In industrial situations, workers exposed to 1,4- dichlorobenzene at high levels are usually directed to wear respirators. Workers involved in the production of the chemical may be exposed to concentrations significantly higher than those encountered by the general population. High exposure levels may result from some consumer products of moth repellents and room deodorizers. Approximately 95% of the environmental release of 1,4- dichlorobenzene occurs during its use, rather than during its manufacture or processing.

ChEBI: A dichlorobenzene carrying chloro groups at positions 1 and 4.

dichlorobenzene: Any one of threeisomeric liquid aromatic compounds,C6H4Cl2. 1,2-Dichlorobenzene (b.p.179°C) and 1,4-dichlorobenzene (b.p.174°C) are made by chlorinatingbenzene with an iron catalyst andseparating the mixed isomers byfractional distillation; 1,3-dichlorobenzene(b.p. 172°C) is made fromone of the other two by catalytic isomerization.The 1,2 isomer is used asan insecticide and in making dyes;the 1,4 compound is employed as adeodorant and moth repellent.

1,4-Dichlorobenzene was first produced commercially in the United States in 1915 (IARC 1982). It is produced by reacting liquid benzene with gaseous chlorine in the presence of a catalyst at moderate temperature and atmospheric pressure. 1,4-Dichlorobenzene is used mainly as a fumigant for the control of moths, molds, and mildews, and as a space deodorant for toilets and refuse containers.

Chemistry Letters, 8, p. 939, 1979
The Journal of Organic Chemistry, 48, p. 250, 1983 DOI: 10.1021/jo00150a020
Tetrahedron Letters, 23, p. 371, 1982 DOI: 10.1016/S0040-4039(00)86833-1

Reactivity with Water No reaction; Reactivity with Common Materials: No reaction; Stability During Transport: Stable; Neutralizing Agents for Acids and Caustics: Not pertinent; Polymerization: Not pertinent; Inhibitor of Polymerization: Not pertinent.

Insecticide, Rodenticide, Fungicide: p-Dichlorbenzene is used primarily as an air deodorant, as moth balls, and in insecticides, which accounts for 90% of the total production of this isomer. Information is not available concerning the production and use of m-DCB. However, it may occur as a contaminant of o-or p-DCB formulations. Both o-and p-isomers are produced almost entirely as byproducts during the production of monochlorobenzene. The major uses of o-DCB are as a process solvent in the manufacturing of toluene diisocyanate and as an intermediate in the synthesis of dyestuffs, herbicides, and degreasers. The para-isomer of dichlorobenzene is the isomer most prominently used in agriculture. Not listed for use in EU countries.

DowTHERM®; EVOLA; PARACIDE®; PARA CRYSTALS®; PARADI®; PARADOW®; PARAMOTH®; PARANUGGETS®; PARAZENE®; PERSIA-PERAZOL®; SANTOCHLOR®; Mixed isomers: DILATIN DBI®; MOTTENSCHUTZMITTEL EVAU P®; MOTT-EX®; TOTAMOTT®

1,4-Dichlorobenzene is reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity from studies in experimental animals.

Biological. In activated sludge, <0.1% degraded (mineralized) to carbon dioxide after 5 d (Freitag et al., 1985). When 1,4-dichlorobenzene was statically incubated in the dark at 25 °C with yeast extract and settled domestic wastewater inoculum, significant biodegradation with gradual acclimation was followed by a deadaptive process in subsequent subcultures. At a concentration of 5 mg/L, 55, 61, 34, and 16% losses were observed after 7, 14, 21, and 28-d incubation periods, respectively. At a concentration of 10 mg/L, only 37, 54, 29, and 0% losses were observed after 7, 14, 21, and 28-d incubation periods, respectively (Tabak et al., 1981).
Surface Water. Estimated half-lives of 1,4-dichlorobenzene (1.5 μg/L) from an experimental marine mesocosm during the spring (8–16 °C), summer (20–22 °C), and winter (3–7 °C) were 18, 10, and 13 d, respectively (Wakeham et al., 1983).
Groundwater. Nielsen et al. (1996) studied the degradation of 1,4-dichlorobenzene in a shallow, glaciofluvial, unconfined sandy aquifer in Jutland, Denmark. As part of the in situ microcosm study, a cylinder that was open at the bottom and screened at the top was installed through a cased borehole approximately 5 m below grade. Five liters of water was aerated with atmospheric air to ensure aerobic conditions were maintained. Groundwater was analyzed weekly for approximately 3 months to determine 1,4-dichlorobenzene concentrations with time. The experimentally determined first-order biodegradation rate constant and corresponding half-life following a 22-d lag phase were 0.05/d and 13.86 d, respectively.
Under anaerobic conditions, 1,4-dichlorobenzene in a plume of contaminated groundwater was found to be very persistent (Barber, 1988).
Photolytic. Under artificial sunlight, river water containing 2 to 5 ppm of 1,4-dichlorobenzene photodegraded to chlorophenol and phenol (Mansour et al., 1989). A carbon dioxide yield of 5.1% was achieved when 1,4-dichlorobenzene adsorbed on silica gel was irradiated with light (λ >290 nm) for 17 h (Freitag et al., 1985). Irradiation of 1,4-dichlorophenol in air containing nitrogen oxides gave 2,5-dichlorophenol (major product), 2,5-dichloronitrobenzene, 2,5-dichlorophenol, and 2,5-dichloro-4-nitrophenol (Nojima and Kanno, 1980). The sunlight irradiation of 1,4- dichlorobenzene (20 g) in a 100-mL borosilicate glass-stoppered Erlenmeyer flask for 56 d yielded 1,860 ppm 2′,4,5′-trichlorobiphenyl (Uyeta et al., 1976).
Chemical/Physical. Anticipated products from the reaction of 1,4-dichlorobenzene with ozone or OH radicals in the atmosphere are chlorinated phenols, ring cleavage products, and nitro compounds (Cupitt, 1980).

1,4-Dichlorobenzene undergoes degradation by the Xanthobacter flavus 14p1 isolated from river sludge by selective enrichment with 1,4-dichlorobenzene, resulting in the degradation products 3,6-dichloro-cis- 1,2-dihydroxycyclohexa-3,5-diene and 3,6- dichlorocatechol. 2,5-Dichloromuconic acid and 2- chloromaleylacetic acid, as well as the decarboxylation product 2-chloroacetoacrylic acid, are identified after enzymatic conversion of 3,6-dichlorocatechol.

o-Dichlorobenzene is a common impurity. The p-isomer has been purified by steam distillation, crystallisation from EtOH or boiling MeOH, air-dried and dried in the dark under vacuum. It has also been purified by zone refining. [Beilstein 5 IV 658.]