77-47-4

A pale yellow liquid with a pungent odor. Density 14.3 lb /gal. Solidifies at 50°F. Insoluble in water. Noncombustible. Very toxic by skin absorption and inhalation. Corrosive to tissue.

HEXACHLOROCYCLOPENTADIENE(77-47-4) is incompatible with strong oxidizing and reducing agents. Also incompatible with many amines, nitrides, azo/diazo compounds, alkali metals (sodium), and epoxides.

Insoluble in water. Reacts slowly with water to form hydrochloric acid.

Toxic by ingestion, inhalation, and skin absorption. Questionable carcinogen.

This compound is very toxic and may be fatal if inhaled, swallowed, or absorbed through the skin. The probable human lethal dose is 50-500 mg/kg, or between 1 teaspoon and 1 ounce for a 150 lb. (70 kg) person. Severe exposure induces pulmonary hyperemia and edema, degenerative and necrotic changes in brain, heart and adrenal glands and necrosis of liver and kidney tubules.

Hexachlorocyclopentadiene is used to produce the flame retardant chlorendic anhydride, which has applications in polyesters; and to produce chlorendic anhydride and chlorendic acid; which is used as a flame retardant in resins. Hexachlorocyclopentadiene is also used as an intermediate in the production of pesticides, such as aldrin, dieldrin, and endosulfan.

Toxic hydrogen chloride, chlorine, and phosgene gases may form in fires. In presence of moisture, will corrode iron and other materials; flammable and explosive hydrogen gas may collect in enclosed space. Will corrode iron and other metals in the presence of moisture. Reacts slowly with water to form hydrochloric acid; however, the reaction is not hazardous. Hazardous polymerization may not occur.

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. Speed in removing material from the skin is of extreme importance. Seek medical attention immediately. If this chemical has been inhaled, remove from exposure, begin rescue breathing (using universal pre cautions, 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 quanti ties of water and induce vomiting. Do not make an uncon scious person vomit. Keep victim quiet and maintain normal body temperature. Medical observation is recom mended for 24 to 48 hours after breathing overexposure, as pulmonary edema may be delayed. As first aid for pulmo nary edema, a doctor or authorized paramedic may consider administering a drug or other inhalation therapy.

UN2646 Hexachlorocyclopentadiene, Hazard Class: 6.1; Labels: 6.1-Poison Inhalation Hazard, Inhalation Hazard Zone B.

Reacts slowly with water to form hydro chloric acid; will corrode iron and most metals in presence of moisture. Explosive hydrogen gas may collect in enclosed spaces in the presence of moisture. Contact with sodium may be explosive.

Hexachlorocyclopentadiene is a pale-yellow to amber-colored, oily liquid. Pungent, unpleasant odor. The odor threshold is 0.15 0.33 ppm.

Pale-yellow liquid; pungent odor. Nonflammable.

Incineration 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 pro duced. Consult with environmental regulatory agencies for guidance on acceptable disposal practices. Generators of waste containing this contaminant (≥100 kg/mo) must con form to EPA regulations governing storage, transportation, treatment, and waste disposal.

Pale yellow to greenish-yellow liquid with a harsh, unpleasant odor. Odor threshold concentrations ranged from 1.4 to 1.6 μg/L (quoted, Keith and Walters, 1992).

Environmental neurotoxicant. Used in the preparation of some insecticides, flame retardants, and resins.

Hexachlorocyclopentadiene (Hex) (molecular weight 272.77) is an organochlorine compound that is used as a raw material in manufacturing other chemicals, including pesticides, flame retardants, resins, dyes, pharmaceuticals, plastics, etc. Hex is a manufactured chemical that does not occur naturally. Hex has no end uses of its own, and is very toxic following acute (short-term) oral and inhalation exposures. It is a light, lemon-yellow liquid that has a sharp musty odor. It easily evaporates into the air; the vapor looks like a blue haze. Most of the Hex in the environment results from its release during production and disposal. It is also used to make flame retardants, resins that won’t burn, shock-proof plastics, esters, ketones, fluorocarbons, and dyes. Animal tests suggest that very high levels can cause death. Human data are limited, but it can cause headaches and irritate the nose, throat, eye, and skin.

Intermediate in the manufacture of chlorinated pesticides; intermediate in the manufacture of flame retardants

The principal end use for Hex is as a key intermediate in the production of chlorinated cyclodiene pesticides, including aldrin, dieldrin, endrin, chlordane, heptachlor, kepone, endosulfan, pentac, isodrin, and mirex. Technical grade chlordane, for example, has been reported to contain impurities of Hex up to 1%. It is also used as an intermediate in the manufacture of flame retardants such as Dechlorane Plus and chlorendic anhydride and, to a lesser extent, in the manufacture of nonflammable resins, polyester resins, pharmaceuticals, unbreakable plastics, acids, esters, ketones, fluorocarbons, and dyes. It has previously been used as a biocide.

Hexachlorocyclopentadiene(Hex) is an Intermediate in the manufacture of chlorinated pesticides and flame retardants. The principal end use for Hex is as a key intermediate in the production of chlorinated cyclodiene pesticides, including aldrin, dieldrin, endrin, chlordane, heptachlor, kepone, endosulfan, pentac, isodrin, and mirex. It is also used as an intermediate in the manufacture of flame retardants such as Dechlorane Plus and chlorendic anhydride and, to a lesser extent, in the manufacture of nonflammable resins, polyester resins, pharmaceuticals, unbreakable plastics, acids, esters, ketones, fluorocarbons, and dyes.

Hexachlorocyclopentadiene is obtained by chlorination of cyclopentadiene in two steps. In addition, using petroleum pentane as raw material, hexachlorocyclopentadiene is synthesized by photochlorination and high temperature chlorination, and the yield is about 70%.

Hexachlorocyclopentadiene is a manufactured chemical that does not occur naturally. Hex has no end uses of its own, and is very toxic following acute (short-term) oral and inhalation exposures. It easily evaporates into the air; the vapor looks like a blue haze. Most of the Hexachlorocyclopentadiene in the environment results from its release during production and disposal. Animal tests suggest that very high levels can cause death. Human data are limited, but it can cause headaches and irritate the nose, throat, eye, and skin.

Biological. When hexachlorocyclopentadiene (5 and 10 mg/L) was statically incubated in the dark at 25 °C with yeast extract and settled domestic wastewater inoculum for 7 d, 100% biodegradation with rapid adaptation was observed (Tabak et al., 1981). In a model ecosystem containing plankton, Daphnia magna, mosquito larva (Culex pipiens quinquefasciatus), fish (Cambusia affinis), alga (Oedogonium cardiacum), and snail (Physa sp.), hexachlorocyclopentadiene degraded slightly, but no products were identified (Lu et al., 1975).
Photolytic. The major photolysis and hydrolysis products identified in distilled water were pentachlorocyclopentenone and hexachlorocyclopentenone. In mineralized water, the products identified include cis- and trans-pentachlorobutadiene, tetrachlorobutenyne, and pentachloropentadienoic acid (Chou and Griffin, 1983). In a similar experiment, irradiation of hexachlorocyclopentadiene in water by mercury-vapor lamps resulted in the formation of 2,3,4,4,5- pentachloro-2-cyclopentenone. This compound hydrolyzed partially to hexachloroindenone (Butz et al., 1982). Other photodegradation products identified include hexachloro-2-cyclopentenone and hexachloro-3-cyclopentenone as major products. Secondary photodegradation products reported include pentachloro-cis-2,4-pentadienoic acid, Z- and E-pentachlorobutadiene, and tetrachlorobutyne (Chou et al., 1987). In natural surface waters, direct photolysis of hexachlorobutadiene via sunlight results in a half-life of 10.7 min (Wolfe et al., 1982).
Chemical/Physical. Slowly reacts with water forming HCl and 1,1-dihydroxytetrachlorocyclopentadiene (Kollig, 1993; NIOSH, 1997). The diene is unstable forming polymers (Kollig, 1993).

Based on structurally similar compounds, hexachlorocyclopentadiene is expected to be soluble in benzene, ethanol, chloroform, methylene chloride, trichloroethylene, and other liquid halogenated solvents.

Based on structurally similar compounds, hexachlorocyclopentadiene is expected to be soluble in benzene, ethanol, chloroform, methylene chloride, trichloroethylene, and other liquid halogenated solvents.

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. Store in tightly closed containers in a cool, well-venti latedarea away from water. Protect containers fromphysical damage. In the presence of moisture, hexachloro-cyclopentadiene will corrode iron and other metals.

Dry the diene with MgSO4, filter, and distil it under vacuum in a nitrogen atmosphere. Irritates skin and eyes, HIGHLY TOXIC. [McBee et al. J Am Chem Soc 77 4378 1955, UV spectra: Idol et al. J Org Chem 20 1746 1955, Beilstein 5 III 308, 5 IV 381.]

Hex’s mechanism of toxicity is incompletely understood. Because of its characteristics as a chlorinated hydrocarbon, it would be expected to induce drug-metabolizing enzymes in the liver.