クロロ酢酸メチル

Excerpt from ERG Guide 131 [Flammable Liquids - Toxic]:

Use water spray, dry powder, alcohol-resistant foam, carbon dioxide. In case of fire: keep drums, etc., cool by spraying with water.

Fresh air, rest. Refer for medical attention.

Remove contaminated clothes. Rinse and then wash skin with water and soap. Refer for medical attention .

First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention.

Rinse mouth. Do NOT induce vomiting. Refer for medical attention .

· CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper not available or no answer, refer to appropriate telephone number listed on the inside back cover.

· ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area.

Call a physician.

General First Aid:

· Wear positive pressure self-contained breathing apparatus (SCBA).

1.0 [ppm]

Suitable extinguishing media: Use water spray, alcohol-resistant foam, dry chemical or carbon dioxide. Advice for firefighters: Wear self-contained breathing apparatus for firefighting if necessary. Further information: Use water spray to cool unopened containers.

ACCIDENTAL RELEASE MEASURES; Personal precautions, protective equipment and emergency procedures: Wear respiratory protection. Avoid breathing vapors, mist or gas. Ensure adequate ventilation. Remove all sources of ignition. Evacuate personnel to safe areas. Beware of vapors accumulating to form explosive concentrations. Vapors can accumulate in low areas. Environmental precautions: Prevent further leakage or spillage if safe to do so. Do not let product enter drains. Methods and materials for containment and cleaning up: Contain spillage, and then collect with an electrically protected vacuum cleaner or by wet-brushing and place in container for disposal according to local regulations.

SRP: 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 air, soil or water; effects on animal, aquatic and plant life; and conformance with environmental and public health regulations. If it is possible or reasonable use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination.

Product: Burn in a chemical incinerator equipped with an afterburner and scrubber but exert extra care in igniting as this material is highly flammable. Offer surplus and non-recyclable solutions to a licensed disposal company. Contact a licensed professional waste disposal service to dispose of this material. Contaminated packaging: Dispose of as unused product.

Remove all ignition sources. Personal protection: chemical protection suit including self-contained breathing apparatus. Collect leaking and spilled liquid in covered plastic containers as far as possible. Absorb remaining liquid in sand or inert absorbent. Then store and dispose of according to local regulations.

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 6(SRC), determined from a structure estimation method(2), indicates that methyl chloroacetate is expected to have very high mobility in soil(SRC). Volatilization of methyl chloroacetate from moist soil surfaces is expected to be an important fate process(SRC) given an estimated Henry's Law constant of 2.4X10-5 atm-cu m/mole(SRC), based upon its vapor pressure, 7.63 mm Hg at 25 °C(3), and water solubility, 4600 mg/L(4). Methyl chloroacetate is expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure(3). Utilizing the Japanese MITI test, 45-95% of the Theoretical BOD was reached in 4 weeks(5) indicating that biodegradation is an important environmental fate process in soil(SRC).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 6(SRC), determined from a structure estimation method(2), indicates that methyl chloroacetate 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 2.4X10-5 atm-cu m/mole(SRC), derived from its vapor pressure, 7.63 mm Hg(4), and water solubility, 4.6X10+4 mg/L(5). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 2 and 16 days, respectively(SRC). According to a classification scheme(6), an estimated BCF of 3(SRC), from an estimated log Kow of 0.63(2) and a regression-derived equation(2), suggests the potential for bioconcentration in aquatic organisms is low(SRC). Utilizing the Japanese MITI test, 45-95% of the Theoretical BOD was reached in 4 weeks(7) indicating that biodegradation is an important environmental fate process in water(SRC). A measured base-catalyzed hydrolysis rate constant of 140 L/mole-sec at 25 °C was reported with corresponding hydrolysis half-lives of 140 to 0.14 hrs at pH values of 6-9(8).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), methyl chloroacetate, which has a vapor pressure of 7.63 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase methyl chloroacetate 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 65 days(SRC), calculated from its rate constant of 2.5X10-13 cu cm/molecule-sec at 25 °C(3). Methyl chloroacetate does not contain chromophores that absorb at wavelengths >290 nm(4) and, therefore, is not expected to be susceptible to direct photolysis by sunlight(SRC).

IDENTIFICATION AND USE: Methyl chloroacetate (MCA) is a colorless liquid. It is used as a solvent and intermediate. HUMAN STUDIES: In man, delayed occurrence of irritation of the conjunctiva is observed after exposure to the vapor. It was suggested that cross reactivity to MCA may occur in an industrial situation. ANIMAL STUDIES: In guinea-pigs MCA induced sensitization. Cross-sensitization with chloroacetic acid ethyl ester has been observed in this species. MCA is corrosive to rabbit skin and is absorbed through the skin (0.5 mL undiluted substance/rabbit leads to death). The substance is severely irritating to the rabbit eye. In rats MCA produced pronounced eye and respiratory tract irritation at concentrations as low as 250 ppm; some animals exposed to this concentration died within a few days. After repeated inhalation exposure to MCA for 28 days at concentrations of 10, 33 or 100 ppm, adverse effects on the breathing (irregular breathing) and on movement (uncoordinated gait) as well as irritant effects (closing together of the eyelids, sneezing, increased frequency of cleaning) and an increase in relative lung weight occurred in rats at the highest concentration. No increase in the incidence of lung tumors has been established after intraperitoneal administration to strain A mice. MCA was not mutagenic in the Salmonella/microsome test in five strains of Salmonella typhimurium or in Escherichia coli either with or without metabolic activation. No induction of micronuclei has been observed in the micronucleus test in the mouse. ECOTOXICITY STUDIES: Testing the acute toxicity to the Daphnia resulted in a 24 hr EC0 of 3.2 mg/L and a 24 hr EC50 of 5.5 mg/L for inhibition of the swimming capability. The 48 hr and 96 hr LC0 in the zebra fish was 1.13 mg/L. For the rainbow trout, 48 hr LC0 < 2.5 mg/L and 48 hr LC100 of 6 mg/L are reported.

/AQUATIC SPECIES/ Testing the acute toxicity to the Daphnia resulted in a 24 hr EC0 of 3.2 mg/L and a 24 hr EC50 of 5.5 mg/L for inhibition of the swimming capability. The 48 hr and 96 hr LC0 in the zebra fish was 1.13 mg/L. For the rainbow trout, 48 hr LC0 < 2.5 mg/L and 48 hr LC100 of 6 mg/L are reported.

Cough. Shortness of breath. Sore throat.

MAY BE ABSORBED! Redness. Pain. Skin burns.

Redness. Pain. Blurred vision.

Abdominal pain. Nausea. Vomiting. Diarrhoea.

Using a structure estimation method based on molecular connectivity indices(1), the Koc of methyl chloroacetate can be estimated to be 6(SRC). According to a classification scheme(2), this estimated Koc value suggests that methyl chloroacetate is expected to have very high mobility in soil(SRC).

Methyl chloroacetate (CAS# 96-34-4) was evaluated for acute inhalation toxicity in male and female rats at dose levels of 1.75, 4.26, and 4.44 mg/L for one-hour. Mortality ratios were 0/5 M, 0/5 F; 2/5 M, 3/5 F; and 4/5 M, 4/5 F, respectively. The estimated LC50 value was 3.69 mg/L (831 ppm).

/HUMAN EXPOSURE STUDIES/ A 23 year old chemical laboratory technician presented with erythema and small blisters on the dorsum of his right hand and forearm. The reaction resulted from a spill of monochloroacetic-acid (MCA). The solution contained 1.5 molar MCA in 94 percent ethanol. He attempted to wash the spill from his arm using water for 10 minutes. After 10 days, the lesions healed, leaving small scars. These scars, after 14 days, became the sites of itchy vesicles. A patch test was performed on day 28, at which time, the patient gave a positive result to the MCA solution at 1 percent in 70 percent methanol. Since it was not considered likely that MCA was the active agent, possible sensitivity to monochloroacetic-acid-ethyl-ester (EMCA) was examined. Strong positive reactions were observed to patch tests with EMCA, whereas the MCA tests were negative. Because plans were underway to use EMCA in a large production process, a guinea-pig maximization test was initiated. Five of the 20 animals tested reacted to EMCA, indicating that this compound is at least a moderate sensitizer. All animals reacted to monochloroacetic-acid-methyl-ester (MMCA). The authors suggest that cross reactivity to MMCA may occur in an industrial situation.

/SIGNS AND SYMPTOMS/ In man, delayed occurrence of irritation of the conjunctiva is observed after exposure to the vapor.