Chemical Properties
solid
Uses
α-1,2,3,4,5,6-Hexachlorocyclohexane is an organochloride which is one of the isomers of hexachlorocyclohexane and is an byproduct of insecticide Lindane (L465990).
General Description
White crystalline powder.
Air & Water Reactions
Insoluble in water.
Reactivity Profile
Halogenated aliphatic compounds, such as ALPHA-HCH, are moderately or very reactive. Reactivity generally decreases with increased degree of substitution of halogen for hydrogen atoms. Materials in this group may be incompatible with strong oxidizing and reducing agents. Also, they may be incompatible with many amines, nitrides, azo/diazo compounds, alkali metals, and epoxides.
Health Hazard
ACUTE/CHRONIC HAZARDS: Carcinogen. Toxic. Irritant. Hazardous decomposition product.
Fire Hazard
Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. Some are oxidizers and may ignite combustibles (wood, paper, oil, clothing, etc.). Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated.
Potential Exposure
The major commercial usage of BHC
is based upon its insecticidal properties. α-BCH is used as
an Agricultural chemical, pesticide, pharmaceutical, and
veterinary drug. The 7-isomer has the highest acute toxic ity, but the other isomers are not without activity. It is gen erally advantageous to purify the 7-isomer from the less
active isomers. The γ-isomer acts on the nervous system of
insects, principally at the level of the nerve ganglia. As a
result, lindane has been used against insects in a wide range
of applications including treatment of animals, buildings,
humans for ectoparasites, clothes; water for mosquitoes;
living plants; seeds and soils. Some applications have been
abandoned due to excessive residues, e.g., stored food stuffs. By voluntary action, the principal domestic producer
of technical grade BHC requested cancellation of its BHC
registrations on September 1, 1976. As of July 21, 1978, all
registrants of pesticide products containing BHC voluntar ily canceled their registrations or switched their former
BHC products to lindane formulations.
First aid
If this chemical gets into the eyes, remove any
contact lenses at once and irrigate immediately for at least
30 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 skin
is of extreme importance. Shampoo hair promptly if con taminated. 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 medi cal attention. Give large quantities of water and induce
vomiting. Do not make an unconscious person vomit.
Shipping
UN2761 Organochlorine pesticides, solid, toxic,
Hazard Class: 6.1; Labels: 6.1-Poisonous materials.
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, epoxides. Decomposes on contact
with powdered iron, aluminum, zinc, and on contact with
strong bases producing trichlorobenzene.
Description
BHC is a white-to-brownish crystalline solid witha musty, phosgene-like odor. Molecular weight = 290.82;Freezing/Melting point = 65℃. Hazard Identification (basedon NFPA-704 M Rating System): Health 2, Flammability 1,Reactivity 0. BCH consists of eight stereoisomers of which thegamma(~) isomer is most insecticidally active and hence mostimportant. See also“Lindane.”
Waste Disposal
A process has been developed
for the destructive pyrolysis of benzene hexachloride @
400 500℃ with a catalyst mixture which contains 5 10%
of either cupric chloride, ferric chloride; zinc chloride; or
aluminum chloride on activated carbon.
Physical properties
Brownish to white monoclinic prisms, crystalline solid or powder with a phosgene-like odor
(technical grade). An odor threshold concentration of 88 μg/kg was reported by Sigworth (1964).
Definition
ChEBI: Beta-hexachlorocyclohexane is the beta-isomer of hexachlorocyclohexane. It has a role as a persistent organic pollutant. It is an organochlorine pesticide and a hexachlorocyclohexane.
Environmental Fate
Biological. Clostridium sphenoides degraded α-BHC to δ-3,4,5,6-tetrachloro-1-cyclo hexane (Heritage and MacRae, 1977a). In four successive 7-day incubation periods, α-
BHC (5 and 10 mg/L) was recalcitrant to degradation in a settled domestic wastewater
inoculum (Tabak et al., 1981).
Soil. Under aerobic conditions, indigenous microbes in contaminated soil produced
pentachlorocyclohexane. However, under methanogenic conditions, α-BHC was converted
to chlorobenzene, 3,5-dichlorophenol and the tentatively identified compound 2,4
Photolytic. When an aqueous solution containing α-BHC was photooxidized by UV
light at 90–95°C, 25, 50 and 75% degraded to carbon dioxide after 4.2, 24.2 and 40.0
hours, respectively (Knoevenagel and Himmelreich, 1976). In basic, aqueous solution
Chemical/Physical. Emits very toxic chloride fumes when heated to decomposition
(Lewis, 1990). α-BHC will hydrolyze via trans-dehydrochlorination of the axial chlorines
resulting in the formation of hydrochloric acid and the intermediate 1,3,4,5,6-pentachlo rocyclo-hexene. The intermediate will undergo further hydrolysis resulting in the formation
of 1,2,3-trichlorobenzene, 1,2,4-trichlorobenzene and hydrochloric acid (Kollig, 1993).
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. Store in tightly closed containers in a cool, well-ventilated area away from alkalis, powdered iron, alumi-num, and zinc. Where possible, automatically pump liquidfrom drums or other storage containers to process contain-ers. A regulated, marked area should be established wherethis chemical is handled, used, or stored in compliance withOSHA Standard 1910.1045.
Purification Methods
Crystallise it from EtOH. Purify it also by zone melting. Possible CANCER AGENT, TOXIC. [: Beilstein 1 H 23, : Beilstein 5 I 8, many isomers : Beilstein 5 III 41, 5 IV 55.]
