Dichloroacetylene

Fresh air, rest. Refer for medical attention.

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.

Refer for medical attention . Rinse mouth.

Excerpt from NIOSH Pocket Guide for Dichloroacetylene:

(General first aid procedures)

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational exposure or environmental contamination. Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in soil or water; effects on animal, aquatic, and plant life; and conformance with environmental and public health regulations.

SRP: The scientific literature for the use of contact lenses in industry is conflicting. The benefit or detrimental effects of wearing contact lenses depend not only upon the substance, but also on factors including the form of the substance, characteristics and duration of the exposure, the uses of other eye protection equipment, and the hygiene of the lenses. However, there may be individual substances whose irritating or corrosive properties are such that the wearing of contact lenses would be harmful to the eye. In those specific cases, contact lenses should not be worn. In any event, the usual eye protection equipment should be worn even when contact lenses are in place.

SRP: Contaminated protective clothing should be segregated in such a manner so that there is no direct personal contact by personnel who handle, dispose, or clean the clothing. Quality assurance to ascertain the completeness of the cleaning procedures should be implemented before the decontaminated protective clothing is returned for reuse by the workers. Contaminated clothing should not be taken home at end of shift, but should remain at employee's place of work for cleaning.

The worker should immediately wash the skin when it becomes contaminated.

Work clothing that becomes wet should be immediately removed due to its flammability hazard.

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 44(SRC), determined from a structure estimation method(2), indicates that dichloroacetylene is expected to have very high mobility in soil(SRC). Volatilization of dichloroacetylene from moist soil surfaces is expected to be an important fate process(SRC) given an estimated Henry's Law constant of 2.0X10-2 atm-cu m/mole(SRC), using a fragment constant estimation method(3). The potential for volatilization of dichloroacetylene from dry soil surfaces may exist(SRC) based upon an estimated vapor pressure of 570 mm Hg(SRC), determined from a fragment constant method(4).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 44(SRC), determined from a structure estimation method(2), indicates that dichloroacetylene is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(3) based upon an estimated Henry's Law constant of 2.0X10-2 atm-cu m/mole(SRC), developed using a fragment constant estimation method(4). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 1.0 hours and 93 hours, respectively(SRC). According to a classification scheme(5), an estimated BCF of 1.4(SRC), from an estimated log Kow of 1.1(6) and a regression-derived equation(7), suggests the potential for bioconcentration in aquatic organisms is low(SRC).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), dichloroacetylene, which has an estimated vapor pressure of 570 mm Hg at 25 °C(SRC), determined from a fragment constant method(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase dichloroacetylene 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 110 hours(SRC), calculated from its rate constant of 1.2X10-12 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). The rate constant for the vapor-phase reaction of dichloroacetylene with ozone has been estimated as 6.1X10-22 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). This corresponds to an atmospheric half-life of about 19,000 days at an atmospheric concentration of 7X10+11 ozone molecules per cu cm(4).

The substance can be absorbed into the body by inhalation of its vapour.

inhalation, skin absorption, ingestion, skin and/or eye contact

Headache. Nausea. Vomiting. Sore throat. Dizziness. Facial paralysis, numbness and tremor.

Redness.

Abdominal pain. Further see Inhalation.

headache, loss of appetite, nausea, vomiting, intense jaw pain, cranial nerve palsy; In Animals: kidney, liver, brain injury; weight loss; [potential occupational carcinogen]

Using a structure estimation method based on molecular connectivity indices(1), the Koc for dichloroacetylene can be estimated to be 44(SRC). According to a classification scheme(2), this estimated Koc value suggests that dichloroacetylene is expected to have very high mobility in soil.

/SIGNS AND SYMPTOMS/ The /chronic and subchronic/ toxic effects were mainly neurological and could last from several days to years.

/SIGNS AND SYMPTOMS/ In the mid-1960s, DCA was detected in the closed system atmospheres of U.S. nuclear submarines and space craft. The crews experienced loss of appetite, extreme nausea, itchy eyes, sore gums, intense jaw pain, and welts on the face and mouth. Disabling nausea was experienced by 85% of the individuals exposed for prolonged periods at concentrations 0.5 to 1.0 ppm.

/SIGNS AND SYMPTOMS/ Dichloroacetylene can cause headaches, dizziness, nausea, vomiting, eye irritation, mucous membrane irritation, and neurological disorders such as paresis and neuralgia in several cranial nerves. Nausea has occurred at concentrations as low as 0.5 to 1.0 ppm.

/SIGNS AND SYMPTOMS/ Extreme nausea was reported by persons exposed to concentrations as low as 2-4 mg/cu m (0.5-1 ppm) dichloroacetylene.

/SIGNS AND SYMPTOMS/ Toxic effects have been reported after accidental exposure to dichloroacetylene in various settings: its generation during use of trichloroethylene as an anesthetic, after use of a solvent mixture containing trichloroethylene as a cleaning agent either domestically or in enclosed work spaces, and during the cleaning of tank cars containing vinylidene chloride copolymers where dichloroacetylene was present. The signs and symptoms observed in each of these reports included headache, dizziness, nausea, vomiting, irritation of the mucous membranes of the mouth and throat as well as eye irritation, facial and oral herpes and neurological disorders. The latter were manifested in paresis and neuralgia in several cranial and cervical nerves. In some cases, the signs and symptoms of cranial-nerve involvement persisted for periods ranging from several days to years. These effects were closely related to findings in dichloroacetylene-exposed animals.

Dichloroacetylene's release as a byproduct in the production of vinylidine chloride or in the dehydrochlorination of trichloroethylene, from exposure of trichloroethylene vapor to Hopcalite in a closed environmental system (submarine) or soda lime in close circuit (rebreathing) anesthesia machines, and from exposure of trichloroethylene liquid in degreaser tanks(1) may result in its release to the environment through various waste streams(SRC).

Dichloroacetylene

Group 3: Not classifiable as to its carcinogenicity to humans

Volume 39: (1986) Some Chemicals Used in Plastics and Elastomers

1999

1998

A by-product of vinylidene chloride production and trichloroethylene thermal decomposition; Not produced commercially; [ACGIH]

Transport forbidden; [HMT]

Dichloroacetylene is not commercially available in large quantities. It is reportedly a byproduct of the synthesis of vinylidene chloride and is not known to be used commercially.

Dichloroacetylene is an... undesired, and non-commercial product of the dehydrochlorination of trichloroethylene. It has resulted form exposure of trichloroethylene vapor to Hopcalite in a closed environmental system (submarine) and soda lime in a closed circuit (rebreathing) anesthesia machines and from exposure of trichloroethylene liquid to caustic in degreaser tanks.