Dimethylarsinic Acid

H301 (94.2%): Toxic if swallowed [Danger Acute toxicity, oral]

H331 (94.2%): Toxic if inhaled [Danger Acute toxicity, inhalation]

H400 (90.4%): Very toxic to aquatic life [Warning Hazardous to the aquatic environment, acute hazard]

H410 (98.1%): Very toxic to aquatic life with long lasting effects [Warning Hazardous to the aquatic environment, long-term hazard]

P261, P264, P270, P271, P273, P301+P316, P304+P340, P316, P321, P330, P391, P403+P233, P405, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 52 reports by companies from 7 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Information may vary between notifications depending on impurities, additives, and other factors. The percentage value in parenthesis indicates the notified classification ratio from companies that provide hazard codes. Only hazard codes with percentage values above 10% are shown. For more detailed information, please visit ECHA C&L website.

EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.

SKIN: IMMEDIATELY flood affected skin with water while removing and isolating all contaminated clothing. Gently wash all affected skin areas thoroughly with soap and water. If symptoms such as redness or irritation develop, IMMEDIATELY call a physician and be prepared to transport the victim to a hospital for treatment.

INHALATION: IMMEDIATELY leave the contaminated area; take deep breaths of fresh air. If symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop, call a physician and be prepared to transport the victim to a hospital. Provide proper respiratory protection to rescuers entering an unknown atmosphere. Whenever possible, Self-Contained Breathing Apparatus (SCBA) should be used; if not available, use a level of protection greater than or equal to that advised under Protective Clothing.

INGESTION: Some heavy metals are VERY TOXIC POISONS, especially if their salts are very soluble in water (e.g., lead, chromium, mercury, bismuth, osmium, and arsenic). IMMEDIATELY call a hospital or poison control center and locate activated charcoal, egg whites, or milk in case the medical advisor recommends administering one of them. Also locate Ipecac syrup or a glass of salt water in case the medical advisor recommends inducing vomiting. Usually, this is NOT RECOMMENDED outside of a physician's care. If advice from a physician is not readily available and the victim is conscious and not convulsing, give the victim a glass of activated charcoal slurry in water or, if this is not available, a glass of milk, or beaten egg whites and IMMEDIATELY transport victim to a hospital. If the victim is convulsing or unconscious, do not give anything by mouth, assure that the victim's airway is open and lay the victim on his/her side with the head lower than the body. DO NOT INDUCE VOMITING. IMMEDIATELY transport the victim to a hospital. (NTP, 1992)

General First Aid:

· Call 911 or emergency medical service.

· Ensure that medical personnel are aware of the material(s) involved, take precautions to protect themselves and avoid contamination.

· Move victim to fresh air if it can be done safely.

· Administer oxygen if breathing is difficult.

· If victim is not breathing:

-- DO NOT perform mouth-to-mouth resuscitation; the victim may have ingested or inhaled the substance.

-- If equipped and pulse detected, wash face and mouth, then give artificial respiration using a proper respiratory medical device (bag-valve mask, pocket mask equipped with a one-way valve or other device).

-- If no pulse detected or no respiratory medical device available, provide continuous compressions. Conduct a pulse check every two minutes or monitor for any signs of spontaneous respirations.

· Remove and isolate contaminated clothing and shoes.

· For minor skin contact, avoid spreading material on unaffected skin.

· In case of contact with substance, remove immediately by flushing skin or eyes with running water for at least 20 minutes.

· For severe burns, immediate medical attention is required.

· Effects of exposure (inhalation, ingestion, or skin contact) to substance may be delayed.

· Keep victim calm and warm.

· Keep victim under observation.

· For further assistance, contact your local Poison Control Center.

· Note: Basic Life Support (BLS) and Advanced Life Support (ALS) should be done by trained professionals.

In Canada, an Emergency Response Assistance Plan (ERAP) may be required for this product. Please consult the shipping paper and/or the "ERAP" section.

Excerpt from ERG Guide 151 [Substances - Toxic (Non-Combustible)]:

SMALL FIRE: Dry chemical, CO2 or water spray.

LARGE FIRE: Water spray, fog or regular foam. If it can be done safely, move undamaged containers away from the area around the fire. Dike runoff from fire control for later disposal. Avoid aiming straight or solid streams directly onto the product.

FIRE INVOLVING TANKS, RAIL TANK CARS OR HIGHWAY TANKS: Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles. Do not get water inside containers. Cool containers with flooding quantities of water until well after fire is out. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks in direct contact with flames. For massive fire, use unmanned master stream devices or monitor nozzles; if this is impossible, withdraw from area and let fire burn. (ERG, 2024)

If material on fire or involved in fire: Extinguish fire using agent suitable for type of surrounding fire. (Material itself does not burn or burns with difficulty.) Use water in flooding quantities as fog. Use foam, dry chemical or carbon dioxide. Keep run-off water out of water sources and sewers.

· 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.

· Keep unauthorized personnel away.

· Stay upwind, uphill and/or upstream.

· Do not touch damaged containers or spilled material unless wearing appropriate protective clothing.

· Stop leak if you can do it without risk.

· Prevent entry into waterways, sewers, basements or confined areas.

· Cover with plastic sheet to prevent spreading.

· Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers.

· DO NOT GET WATER INSIDE CONTAINERS.

· For solids, prevent dust cloud and avoid inhalation of dust.

Excerpt from ERG Guide 151 [Substances - Toxic (Non-Combustible)]:

IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids.

SPILL: Increase the immediate precautionary measure distance, in the downwind direction, as necessary.

FIRE: If tank, rail tank car or highway tank is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2024)

Immediate precautionary measure

· Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids.

· For highlighted materials: see Table 1 - Initial Isolation and Protective Action Distances.

· For non-highlighted materials: increase the immediate precautionary measure distance, in the downwind direction, as necessary.

· If tank, rail tank car or highway tank is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions.

Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number D004, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.

Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number U136, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.

Storage: To convert the gas-cleaning residues obtained during the metallurgical processing of arsenic-containing ores into a portable and less water-soluble form, the metals are precipitated as hydroxides by using an excess of lime water and the arsenic is precipitated as calcium arsenate and calcium arsenite. This "arsenic sludge" is recycled, on the one hand, in order not to lose the valuable metals, and on the other, in order to reduce the problem of arsenic sludge disposal.

A poor candidate for incineration.

If material not on fire and not involved in fire: Keep sparks, flames, and other sources of ignition away. Keep material out of water sources and sewers.

Personnel protection: Avoid breathing dusts, and fumes from burning material. Keep upwind. ... Avoid bodily contact with the material. ... Do not handle broken packages unless wearing appropriate personal protective equipment.

Excerpt from ERG Guide 151 [Substances - Toxic (Non-Combustible)]:

Do not touch damaged containers or spilled material unless wearing appropriate protective clothing. Stop leak if you can do it without risk. Prevent entry into waterways, sewers, basements or confined areas. Cover with plastic sheet to prevent spreading. Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers. DO NOT GET WATER INSIDE CONTAINERS. For solids, prevent dust cloud and avoid inhalation of dust. (ERG, 2024)

KEEP WELL CLOSED.

DO NOT STORE NEAR FERTILIZERS, SEEDS, INSECTICIDES, /OR/ FUNGICIDES.

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

· Wear chemical protective clothing that is specifically recommended by the manufacturer when there is NO RISK OF FIRE.

· Structural firefighters' protective clothing provides thermal protection but only limited chemical protection.

2.8 [mg/m3]

23 [mg/m3]

140 [mg/m3]

Acute Oral: 0.005 mg/kg/day (L134)

Chronic Oral: 0.0003 mg/kg/day (L134)

Chronic Inhalation: 0.01 mg/m3 (L134)

Small Fire

· Dry chemical, CO2 or water spray.

Large Fire

· Water spray, fog or regular foam.

· If it can be done safely, move undamaged containers away from the area around the fire.

· Dike runoff from fire control for later disposal.

· Avoid aiming straight or solid streams directly onto the product.

Fire Involving Tanks, Rail Tank Cars or Highway Tanks

· Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles.

· Do not get water inside containers.

· Cool containers with flooding quantities of water until well after fire is out.

· Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank.

· ALWAYS stay away from tanks in direct contact with flames.

· For massive fire, use unmanned master stream devices or monitor nozzles; if this is impossible, withdraw from area and let fire burn.

... The following countries had adopted the ... TLV of 0.5 mg/cu m: Austria, Belgium, Finland, Japan, and Holland. Czechoslavakia, East Germany, Hungary and Poland ... USSR ... 0.3 mg/cu m; Romania and Switzerland, 0.2 mg/cu m; Sweden 0.05 mg/cu m; and Italy 0.25 mg/cu m. /Arsenic and sol cmpd/

Tolerances are established for residues of the defoliant cacodylic acid (dimethylarsenic acid), expressed as As2O3, in or on raw agricultural commodities as follows: 2.8 ppm in or on cottonseed; 1.4 ppm in the kidney and liver of cattle; and 0.7 ppm in meat, fat, and meat byproducts (except kidney and liver) of cattle.

Tolerances for total residues of combined arsenic (calculated as As) in food are established as follows: (a) In edible tissues & in eggs of chickens & turkeys: 0.5 ppm in uncooked muscle tissue; 2 ppm in uncooked edible by-products; & 0.5 ppm in eggs. (b) In edible tissues of swine: 2 ppm in uncooked liver & kidney; 0.5 ppm in uncooked muscle tissue & by-products other than liver & kidney. /Arsenic/

Dust respirator; goggles; protective clothing. (USCG, 1999)

RUBBER GLOVES, GOGGLES OR FACE SHIELD, RUBBER APRON.

Cacodylic acid appears as a colorless, odorless crystalline solid. Melting point 195-196 °C. Toxic by ingestion and irritating to skin and eyes.

Hygroscopic solid; [Merck Index] Colorless odorless hygroscopic solid; [CAMEO] White crystalline solid; [MSDSonline]

Crystals from alcohol and ether

Colorless

TRICLINIC CRYSTALS

White; water solutions may be dyed blue

Odorless

greater than 392 °F at 760 mmHg (NTP, 1992)

383 to 385 °F (NTP, 1992)

Very soluble (NTP, 1992)

Soluble in acetic acid

Soluble in ethanol; insoluble in diethyl ether

In water, 2X10+6 mg/l @ 25 °C.

greater than 1.1 at 68 °F (est.) (USCG, 1999)

0.0000001 [mmHg]

COMPLETELY STABLE IN STORAGE.

When heated to decomposition it emits toxic fumes of /arsenics/.

Decomposed by powerful oxidizing or reducing agents.

All formulations are mildly corrosive.

pKa = 1.57

108.6 Ų [M+H]+ [CCS Type: DT; Buffer gas: N2; Ionization: APCI+; Dataset: TOXCAST; Source Identifier: DTXSID7020508]

109.0 Ų [M+H]+ [CCS Type: DT; Buffer gas: N2; Ionization: ESI+; Dataset: TOXCAST; Source Identifier: DTXSID7020508]

119.2 Ų [M-H]- [CCS Type: DT; Buffer gas: N2; Ionization: ESI-; Dataset: TOXCAST; Source Identifier: DTXSID7020508]

112.5 Ų [M+H]+ [CCS Type: TW; Method: calibrated with polyalanine and drug standards]

Hygroscopic

Forms water-soluble sodium and potassium salts

It is decomp by powerful oxidizing or reducing agents.

Compatible with hard waters.

Metals -> Arsenic Compounds, Organic

Carcinogens

Pesticide -> EPA IRIS

Hygroscopic. Water soluble.

Acids, Carboxylic

CACODYLIC ACID is a weak acid. Dissolves in water to yield solutions containing more hydrogen ions than pure water contains and so having a pH less than 7.0. Is neutralized exothermically by all bases to produce water plus a salt. Reacts (but usually slowly) with active metals to form gaseous hydrogen and a metal salt. Such reactions occur in principle for the solid acid but are quite slow if the solid acid remains dry. The solid may absorb enough water from the air and dissolve sufficiently in it to corrode or dissolve iron, steel, and aluminum parts and containers. Reacts with cyanide salts to generate gaseous hydrogen cyanide. Flammable and/or toxic gases and heat may be generated with diazo compounds, dithiocarbamates, isocyanates, mercaptans, nitrides, and sulfides. Also may react with sulfites, nitrites, thiosulfates (to give H2S and SO3), dithionites (SO2), to generate flammable and/or toxic gases and heat. Reaction with carbonates and bicarbonates generates a harmless gas (carbon dioxide) but still some heat. Can be oxidized exothermically by strong oxidizing agents and reduced by strong reducing agents; a wide variety of products is possible. May initiate polymerization reactions; may catalyze (increase the rate of) chemical reactions.

HAZARDOUS WHEN WATER SOLN IS IN CONTACT WITH ACTIVE METALS, E.G., /IRON, ALUMINUM, AND ZINC/.

... WHEN WATER SOLN OF ARSENICALS ARE IN CONTACT WITH ACTIVE METALS SUCH AS /IRON, ALUMINUM, OR ZINC/, HIGHLY TOXIC FUMES OF ARSENIC ARE EMITTED. /ARSENIC CMPD/

At pH 7, dimethylarsinic acid forms a water-soluble sodium salt (sodium dimethylarsinate), which is deliquescent.

Arsenic and its metabolites disrupt ATP production through different mechanisms. At the level of the citric acid cycle, arsenic inhibits the pyruvate dehydrogenase and uncouples the oxidative phosphorylation by competing with phosphate. This leads to inhibition of energy-linked reduction of NAD+, mitochondrial respiration, and ATP synthesis. Hydrogen peroxide production is increased, leading to oxidative stress due to the formation of reactive oxygen species. Arsenic's carginogenicity is influenced by the arsenical binding of tubulin, which results in aneuploidy, polyploidy and mitotic arrests. The binding of other arsenic protein targets may also cause altered DNA repair enzyme activity, altered DNA methylation patterns and cell proliferation. (T1, A17)

Arsenic and its metabolites disrupt ATP production through several mechanisms. At the level of the citric acid cycle, arsenic inhibits pyruvate dehydrogenase and by competing with phosphate it uncouples oxidative phosphorylation, thus inhibiting energy-linked reduction of NAD+, mitochondrial respiration, and ATP synthesis. Hydrogen peroxide production is also increased, which might form reactive oxygen species and oxidative stress. Arsenic's carcinogenicity is influenced by the arsenical binding of tubulin, which results in aneuploidy, polyploidy and mitotic arrests. The binding of other arsenic protein targets may also cause altered DNA repair enzyme activity, altered DNA methylation patterns and cell proliferation. (T1, A17)

Cacodylic acid

Cancer Classification: Group B2 Probable Human Carcinogen

Dimethylarsinic acid

Group 2B: Possibly carcinogenic to humans

Volume 100C: (2012) Arsenic, Metals, Fibres, and Dusts

2B, possibly carcinogenic to humans. (L135)

3, not classifiable as to its carcinogenicity to humans. (L135)

Arsenic poisoning can lead to death from multi-system organ failure, probably from necrotic cell death, not apoptosis. Arsenic is also a known carcinogen, especially in skin, liver, bladder and lung cancers. (T1, L20)

Hypovolemia from capillary leakage (third-spacing of fluids) is a common, serious, early effect. Muscle cramps, facial edema, bronchitis, dyspnea, chest pain, dehydration, intense thirst, and fluid-electrolyte disturbances are also common following significant exposures. A garlic-like odor of the breath and feces may also occur. After absorption, arsenic may cause multi-organ failure by inhibiting sulfhydryl-containing enzymes. Encephalopathy, with headache, lethargy, mental confusion, hallucinations, emotional lability, memory loss and delirium may occur; seizures, stupor, convulsions, coma, and death may follow within 24 hours of a severe acute exposure. Dysrhythmias (particularly QTc prolongation and torsade de pointes), cardiomyopathy, ARDS, hepatitis, rhabdomyolysis, hemolysis, and renal failure may develop over several days. The sequence of chronic poisoning involves hyperpigmentation, and eczematoid and allergic dermatitis. muscle fasciculations; gross tremors; ataxia; incoordination; and mental confusion. Muscular weakness, limb tenderness and difficulty walking may follow. The final phase consists of peripheral sensory neuropathy of the hands and feet. That may be associated with a motor neuropathy as well (T36).

Oral (L2) ; inhalation (L2); dermal (L2)

Oral (L2) ; inhalation (L2); dermal (L2)

Exposure to lower levels of arsenic can cause nausea and vomiting, decreased production of red and white blood cells, abnormal heart rhythm, damage to blood vessels, and a sensation of “pins and needles” in hands and feet. Breathing high levels of inorganic arsenic can provoque sore throat or irritated lungs. Arsenic also affects the brain, causing neurological disturbances such as headaches, confusion, and drowsiness. (A1)

Initial signs and symptoms of arsenic ingestion include burning lips, throat constriction and dysphagia, followed by excruciating abdominal pain, hemorrhagic gastritis, gastroenteritis, severe nausea, projectile voting, profuse "rice water-like" diarrhea, with hypovolemia that may result in hypotension and an irregular pulse. The sequence of chronic poisoning involves weakness, anorexia, hepatomegaly, jaundice, and gastrointestinal complaints, followed by conjunctivitis, irritation of the throat and respiratory tract. ther effects of chronic exposure include conjunctivitis with irritation and lacrimation; hair, skin and nail changes; hyperkeratosis of feet and hands; and melanosis, with pigment spots in corneal and conjunctival epithelium. Peripheral nervous system symptoms may include numbness, burning, and tingling of the hands and feet; pain; paresthesias; tenderness (T36).

IARC Carcinogen - Class 3: Chemicals are not classifiable by the International Agency for Research on Cancer.

PPRTV Archive

LCLo (rat) = 4,900 mg/m3/4h

LD50: 644 mg/kg (Oral, Rat) (T14)

LD50: 720 mg/kg (Intraperitoneal, Rat) (T32)

LD50: 2600 mg/kg (Oral, Rat)

LD50 Rat oral 700 mg/kg

LC50 Rat male inhalation (exposure to dust): > 6.9 mg/l/2 hr

LC50 Rat female inhalation (exposure to dust): > 3.9 mg/l/2 hr

LC50 Mouse inhalation (exposure to dust): > 6.4 mg/l/2 hr

For more Non-Human Toxicity Values (Complete) data for DIMETHYLARSENIC ACID (12 total), please visit the HSDB record page.

Arsenic poisoning can be treated by chelation therapy, using chelating agents such as dimercaprol, EDTA or DMSA. Charcoal tablets may also be used for less severe cases. In addition, maintaining a diet high in sulfur helps eliminate arsenic from the body. (L20)

Aggressive decontamination with gastric lavage is recommended if the patient has consumed a potentially life-threatening dose and if the patient is not vomiting. Administer charcoal as a slurry (T36).

The influence of the methyltransferase inhibitor periodate oxidized adenosine on the metabolism of arsenite was investigated in mice and rabbits. Groups of male NMRI-mice and New Zealand rabbits were given intraperitoneal (ip) injections of 100 um periodate oxidized adenosine per kilogram (kg) 15 min before an intravenous injection of 0.04 mg/kg (74)As labeled arsenite or injections of (74)As labeled arsenite only. These animals were kept for 16 to 72 hr in metabolic cages designed to separate urine and feces. The urinary concn of dimethylarsenic acid (DMA), the major arsenic metabolite, was measured. Other groups of animals were injected with (74)As labeled arsenite and periodate oxidized adenosine or (74)As labeled arsenite only and killed between 1 to 72 hr. Blood, liver, kidney, lung, epididymis, and portions of skin were removed and measured for (74)As content in a gamma scintillation counter. Also, subcellular fractionation of liver tissue was performed and the concentration of (74)As was ascertained. The urinary excretion of (74)As was lower in mice and rabbits treated with periodate oxidized adenosine prior to arsenite administration than in animals treated with arsenite only. Injection of periodate oxidized adenosine prior to arsenite produced a 25 to 70% decrease in the production of dimethylarsenic acid, implying that S-adenosylmethionine was the methyl donor for the methylation of inorganic arsenic in vivo. The fecal excretion of (74)As was less than 4% of the dose, independent of treatment and animal species. Periodate oxidized adenosine treated animals had 2 to 6 times higher concentrations of (74)As in tissues than that in controls, the effect being first observed in liver tissues. The subcellular distribution of (74)As in liver of mice was not affected by periodate oxidized adenosine treatment in that 50% was found in the soluble cytoplasmic fraction and 20 to 30% was found in thenuclear fraction, independent of the treatment.

FIRST AID: Get medical aid. Eyes, skin, flush with flowing water immediately and continuously for 15 minutes. Inhalation, materials nonvolatile but if spray drift is inhaled, treat as ingestion. ... May be treated as for general arsenic poisoning.

/CACODYLIC ACID IS/ HARMFUL IF SWALLOWED. AVOID INHALATION OF SPRAY MIST.

To analyze the mechanisms of arsenic induced gene damage, found previously in lungs of mice and rats orally administered dimethylarsinic acid, a major metabolite of inorganic arsenics, an in vitro system with human alveolar type II (L-132) cells was used. The exposure to 10 mM dimethylarsinic acid for 10 hr caused significant single-strand breaks in DNA of the cells. At an earlier period of the exposure, the replicative DNA synthesis was markedly suppressed, and the chain length of the nascent DNA was shorter than that of the control, suggesting that the template DNA received some modification other than strand breaks. The modification, being repairable, was sensitive to UV irradiation to cause strand breaks.

Ingestion of 77 mg/kg arsenic (as dimethyl arsenic acid and dimethyl arsenate) induced vomiting, abdominal pain, hyperactive bowel, and diarrhea ... .

Support for sensitization to DMA is provided in a case control study of a 26-yr-old woman who was occupationally exposed to DMA and experienced eczema on her face ... . Patch testing confirmed an allergic reaction to DMA, and avoidance of DMA resulted in disappearance of the symptoms.

... FORESTRY WORKER ... INJECTING TREES WITH SILVICIDE, CHIEFLY CONTAINING CACODYLIC ACID, COMPLAINED OF ANOREXIA, NAUSEA, ABDOMINAL PAIN & ... /HAD/ ELEVATED ARSENIC URINE LEVEL. FREE OF EXPOSURE ... SYMPTOMS GRADUALLY SUBSIDED. /ARSENIC SILVICIDE/

100 & 1000 PPM BY WT ... CACODYLIC ACID /IN 60% SUCROSE SYRUP IS/ ... EXTREMELY TOXIC TO NEWLY EMERGED WORKER BEES ... MODERATELY TOXIC @ 10 PPM BY WT. ... NO DIFFERENCES IN TOXICITY ... OBSERVED BETWEEN PURIFIED & COMMERCIALLY FORMULATED HERBICIDES.

PRIMARY DERMAL IRRITATION INDEX--RABBITS--0.3. ESSENTIALLY NONIRRITATING TO THE SKIN WHEN ACCIDENTALLY APPLIED TOPICALLY. ... OCULAR IRRITATION SCORE--RABBITS--2.0. ESSENTIALLY NON-IRRITATING TO THE EYE WHEN ACCIDENTALLY EXPOSED.

... EFFECT ON CELL DIVISION /IN PLANTS WAS STUDIED/. CACODYLIC ACID ... ACTED ON SPINDLES (COLCHINIC EFFECT). CACODYLIC ACID & CYCLOHEXYLARSINIC ACID WERE THE MOST POWERFUL ARSENICALS EXAMINED IN ACTING ON CHROMOSOMES. AS A RESULT, THEY ARE CONSIDERED MITOTIC POISONS.

FETUSES FROM PREGNANT HAMSTERS TREATED IP WITH 1000 MG CACODYLIC ACID ON DAYS 8, 11, OR 12 OF GESTATION WERE RESORBED. TREATMENT WITH 900 MG/KG CAUSED A HIGH DEGREE OF FETAL WASTAGES, WITH THE GREATEST EFFECTS BEING DUE TO TREATMENT ON DAYS 8 OR 9. GROWTH WAS REDUCED FOLLOWING ALL TREATMENTS EXCEPT DAY 8 & GROSS MALFORMATIONS WERE OBSERVED FOLLOWING ALL TREATMENTS EXCEPT DAY 12.

For more Non-Human Toxicity Excerpts (Complete) data for DIMETHYLARSENIC ACID (18 total), please visit the HSDB record page.

1.30e+03

1.30e+03

1.60e+04

4.00e+02

8.0E+01(G)

1.10e-01

2.00e-02

Volatile

3.80e+03

4.90e+04

1.20e+03

8.0E+01 (G)

Dimethylarsenic acid's production and use as an herbicide, soil sterilant and in timber thinning will result in its direct release to the environment. Inorganic arsenic compounds in water or soil can undergo biochemical transformations that may result in the formation of dimethylarsenic acid. Dimethylarsenic acid is also formed in the ambient atmosphere by the oxidation of gaseous methylated arsines that are emitted to air as biological conversion products from bacteria and fungi. If released to air, an estimated vapor pressure of 4.6X10-3 mm Hg at 25 °C indicates dimethylarsenic acid will exist solely as a vapor in the ambient atmosphere. Vapor-phase dimethylarsenic acid will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for this reaction in air is estimated to be 31 days. If released to soil, dimethylarsenic acid is expected to be tightly bound to soil and have low mobility. The pKa of dimethylarsenic acid is 1.57, indicating that this compound will exist as the anion in the environment. Volatilization from moist soil surfaces is not expected to be an important fate process because the anion is not expected to volatilize. Dimethylarsenic is expected to biodegrade in soil; incubation of dimethylarsenic acid in two soils for six weeks resulted in 4-43% degradation. If released into water, dimethylarsenic acid is expected to adsorb to suspended solids and sediment. Dimethylarsenic acid is expected to biodegrade in water. In a die-away test using river sediments, the degradation half-life of dimethylarsenic acid was about 30 days. Volatilization from water surfaces is not expected to be an important fate process because the anion is not expected to volatilize. A BCF of 21 for mosquito fish suggests bioconcentration in aquatic organisms is low. The organic functional groups of dimethylarsenic acid are generally resistant to aqueous environmental chemical hydrolysis. Occupational exposure to dimethylarsenic acid may occur through inhalation and dermal contact with this compound at workplaces where dimethylarsenic acid is produced or used. Urinary excretion of arsenic has been directly correlated with worker exposure to dimethylarsenic acid. Monitoring data indicate that the general population may be exposed to dimethylarsenic acid via inhalation of ambient air containing methylated arsines. (SRC)

Inorganic arsenic compounds in water or soil can undergo biochemical transformations that may result in the formation of dimethylarsenic acid(1); these transformations are most likely to occur under aerobic or slightly anaerobic conditions(1). Dimethylarsenic acid is formed in the ambient atmosphere by the oxidation of gaseous methylated arsines that are emitted to air as biological conversion products from bacteria and fungi(2-4); since biological activity is greatest in the summer and least in the winter, the highest atmospheric levels of dimethylarsenic acid are found during the summer and the lowest levels are found in winter(2).

Dimethylarsenic acid's production and use as an herbicide, soil sterilant, and in timber thinning(1) will result in its direct release to the environment(SRC).

TERRESTRIAL FATE: ... /CACODYLIC ACID/ REACTS /IN SOIL/ WITH TRIVALENT CHROMIUM, SILVER NITRATE & OTHER METAL IONS ... MAY FORM CYCLIC TYPES OF CMPD UNDER CERTAIN CONDITIONS.

TERRESTRIAL FATE: CHEM & BIOLOGICAL TRANSFORMATION OF ARSENICAL IN SOIL: IN SOIL CACODYLIC ACID MAY UNDERGO SALT FORMATION, ADSORPTION, ION EXCHANGE, DEMETHYLATION (OXIDATIVE), REDN, & METHYLATION (REDUCTIVE). /FROM TABLE/

TERRESTRIAL FATE: CACODYLIC ACID FORMED INSOL CMPD WITH SOIL.

TERRESTRIAL FATE: Dimethylarsenic acid is expected to have low mobility in soils(1-4). Organoarsenicals, such as dimethylarsinic acid, are adsorbed by clays soils(1). After rapid initial adsorption, changes occur which result in the redistribution of dimethylarsinic acid into a less soluble form associated with aluminum in the soil(1). The dimethylarsinic acid is fixed by iron and aluminum in the soil, although not as strongly as inorganic arsenate(1). Arsenic residues in browse and herbaceous vegetation in Douglas fir, ponderosa pine, and western larch forests in which trees were treated with cacodylic acid, sodium salt for thinning were relatively low(1). Large quantities of arsenic did not move from the forest floor into the soil, indicating that arsenic residues were tightly bound in the foliage(1). Only small amounts of arsenic were detected in streams in forests treated with cacodylic acid or its sodium salt(1). A pKa of 1.57(5) indicates that dimethylarsenic acid will ionize in water(SRC); therefore, dimethylarsenic acid is expected to be essentially nonvolatile from moist soil surfaces(SRC). Dimethylarsenic acid is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 4.6X10-3 mm Hg(SRC), determined from a fragment constant method(6). Generation of C-14 labeled CO2 from C-14 labeled dimethylarsenic acid in a clay loam soil reached about 13% (over 98 days of incubation) in soil that had been adapted to dimethylarsenic acid, but was less than 2% in unadapted soil(7); the degradation was presumably microbial in nature(7). Incubation of dimethylarsenic acid in two Japanese soils for a period of six weeks resulted in 4-43% degradation(8); 0% degradation occurred in sterile controls(8). In another study in soil, 36% of dimethylarsenic acid was converted to a volatile organoarsenical compound and 47% to carbon dioxide and arsenate within a 24-week period(9).

For more Environmental Fate (Complete) data for DIMETHYLARSENIC ACID (6 total), please visit the HSDB record page.

DEGRADATION OF CACODYLIC ACID TO CARBON DIOXIDE & ARSENATE /IN SOIL/ APPEARS TO BE MICROBIAL IN NATURE & IS PROBABLY DEPENDENT ON SOIL ORGANIC MATTER CONTENT ... .

... CACODYLIC ACID APPARENTLY DEGRADED AEROBICALLY BY 2 MECHANISMS: CLEAVAGE OF C-AS BOND(S) & REDN TO VOLATILE ORGANOARSENICAL, PROBABLY DIMETHYLARSINE OR AN OXIDE. UNDER ANAEROBIC CONDITIONS, ONLY VOLATILE CMPD FORMED. DEGRADATION WAS SLOW ... 15-80% (14)C ACTIVITY LOST IN 32 WK, DEPENDING ON SOIL TYPE.

When applied to soil, cacodylic acid decreased by two routes. The observation of a pungent garlic odor suggested production of alkylarsine and a source of arsenic loss. Degradation to CO2 and arsenate by microbial action was another route for cacodylic loss.

In a die-away test using river sediments, the degradation half-life of dimethylarsenic acid was about 30 days(1); degradation of dimethylarsenic acid corresponded with formation of arsenate(1); no degradation occurred in sterile controls(1). Generation of C- 14 labeled CO2 from C-14 labeled dimethylarsenic acid in a clay loam soil reached about 13% (over 98 days of incubation) in soil that had been adapted to dimethylarsenic acid, but was less than 2% in unadapted soil(2); the degradation was presumably microbial in nature(2). Incubation of dimethylarsenic acid in two Japanese soils for a period of six weeks resulted in 4-43% degradation(3); 0% degradation occurred in sterile controls(3). In another study in soil, 36% of dimethylarsenic acid was converted to a volatile organoarsenical compound and 47% to carbon dioxide and arsenate within a 24-week period(4).

ANAEROBIC: Under anaerobic conditions, 61% of dimethylarsenic acid was converted to a volatile organoarsenical compound within a 24-week period and was lost from the soil system(1).

The rate constant for the vapor-phase reaction of dimethylarsenic acid with photochemically-produced hydroxyl radicals has been estimated as 5.2X10-13 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 31 days at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). The organic functional groups of dimethylarsenic acid are generally resistant to aqueous environmental chemical hydrolysis(2). Dimethylarsenic acid reacts with iron and aluminum hydroxides in soil to form insoluble compounds(3). Dimethylarsenic acid does not chemically oxidize under mild oxidizing conditions(4).

A BCF of 21 was measured for mosquito fish in a model ecosystem study(1). According to a classification scheme(2), this BCF suggests the potential for bioconcentration in aquatic organisms is low(SRC).

Organoarsenicals, such as dimethylarsinic acid, are adsorbed by clays soils(1). After rapid initial adsorption, changes occur which result in the redistribution of dimethylarsinic acid into a less soluble form associated with aluminum in the soil(1). The dimethylarsinic acid are fixed by iron and aluminum in the soil, although not as strongly as inorganic arsenate(1). Leaching tests conducted in specially constructed boxes with clay, silt loam, and sandy soils noted strong adsorption to all soils, although a small degree of leaching did occur(2). The adsorption of dimethylarsenic acid to sediments and soil was found to depend on clay content, iron oxide content, and pH(3,4); adsorption increases with increasing clay and iron oxide content and with higher pH(3,4). Herbicidal applications of dimethylarsenic acid that were applied to forest floors in the northwestern US were found to be tightly bound, and did not leach in soil(5).

A pKa of 1.57(1) indicates that dimethylarsenic acid will ionize in water(SRC); therefore, dimethylarsenic acid is expected to be essentially nonvolatile from water surfaces(SRC). Dimethylarsenic acid is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 4.6X10-3 mm Hg(SRC), determined from a fragment constant method(2).

IN INTERSTITIAL WATER A FEW PERCENT /OF ARSENIC WAS/ DIMETHYLARSENIC ACID.

SURFACE WATER: The concentrations of dimethylarsenic acid in a wide range of fresh natural waters including lakes, rivers and ponds in and around Tampa, FL were in the range of <0.02-0.62 ug/l(1). Lake, river and pond waters from the Moira River area in Ontario, Canada, which flows through an abandoned smelter (still emitting high levels of arsenic from its watershed) contained 2.3-3.3 ug/l of dimethylarsenic acid(2). SEAWATER: Saline waters at several locations along the shores of Tampa Bay contained 0.2-1.0 ug/l of dimethylarsenic acid(1).

DRINKING WATER: No dimethylarsenic acid was detected (detection limit of 0.02 ug/l) in Tampa, FL tap waters(1).

GROUNDWATER: The concentration of dimethylarsenic acid in well water at a remote camping site near the Withlacocochee River in FL was 0.2 ug/l(1).

RURAL/REMOTE: The levels of dimethylarsenic acid in air over an unpolluted island and over a rural inland area in Japan were in the range from 0.007 to 0.071 ng arsenic/cu m during 1984-1986 monitoring(1); a seasonal variation was observed with highest levels in summer and lowest levels in winter(1). Upper levels of dimethylarsenic acid of 0.030 to 0.270 ng arsenic/cu m were detected in Japanese air(2); the dimethylarsenic acid was in the form of inhalable particles(2).

THE DEFOLIANT FORMULATION BOLLS-EYE, WHICH CONTAINS CACODYLIC ACID & ITS SODIUM SALT, & INORGANIC ARSENIC WAS SPRAYED ON COTTON & RESIDUES WERE DETERMINED 2, 4, 8, & 25 DAYS AFTER APPLICATION. TOTAL ARSENIC, METHANEARSINIC ACID & TOTAL CACODYLICS & ARSENATE PEAKED IMMEDIATELY AFTER SPRAYING & DECLINED. BY DAY 8 THE LEVELS WERE NOT SIGNIFICANTLY ABOVE PRE-APPLICATION BACKGROUND LEVELS. COTTON SEED (TOTAL ARSENIC) LEVELS WERE LOW, SUGGESTING NO DETECTABLE TRANSPORT.

... WORKERS THINNING FORESTS ... ARE AT RISK OF EXPOSURE.

NIOSH (NOES Survey 1981-1983) has statistically estimated that 354 workers (304 of these are female) are potentially exposed to dimethylarsenic acid in the US(1). The NOES Survey does not include farm workers. Occupational exposure to dimethylarsenic acid may occur through inhalation and dermal contact with this compound at workplaces where dimethylarsenic acid is produced or used(SRC). Urinary excretion of arsenic has been directly correlated with worker exposure to dimethylarsenic acid(2,3). Monitoring data indicate that the general population may be exposed to dimethylarsenic acid via inhalation of ambient air containing gaseous methylated arsines(SRC).

Urinary excretion of arsenic has been directly correlated with worker exposure to dimethylarsenic acid(1,2). Blood levels of arsenic does not seem to be correlated with worker exposure to dimethylarsenic acid(1). Herbicide workers using poor handling and application techniques had urine arsenic levels as high as 1.8 ppm which corresponded to an exposure of at least 0.036 mg As/kg body wt/day(2); proper handling techniques and protective gear reduced exposure by an order of magnitude(2). In forestry workers, the urinary dimethylarsenic acid level during an 11 week observation period ranged from 24-172 ug/24 hr compared to a range of 26-73 ug/24 hr for non-exposed workers(1). Urine samples of humans were found to contain an average of 15 ug/l of dimethylarsenic acid which constituted an average of 66% of the total urinary excretion of arsenic(3).

Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number D004, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.

Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number U136, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.

Storage: To convert the gas-cleaning residues obtained during the metallurgical processing of arsenic-containing ores into a portable and less water-soluble form, the metals are precipitated as hydroxides by using an excess of lime water and the arsenic is precipitated as calcium arsenate and calcium arsenite. This "arsenic sludge" is recycled, on the one hand, in order not to lose the valuable metals, and on the other, in order to reduce the problem of arsenic sludge disposal.

A poor candidate for incineration.

/GUIDE 151: SUBSTANCES - TOXIC (Non-combustible)/ Fire or Explosion: Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. Containers may explode when heated. Runoff may pollute waterways.

/GUIDE 151: SUBSTANCES - TOXIC (Non-combustible)/ Health: Highly toxic, may be fatal if inhaled, swallowed or absorbed through skin. Avoid any skin contact. Effects of contact or inhalation may be delayed. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may be corrosive and/or toxic and cause pollution.

/GUIDE 151: SUBSTANCES - TOXIC (Non-combustible)/ Public Safety: CALL Emergency Response Telephone Number on Shipping Paper first. If Shipping Paper not available or no answer, refer to appropriate telephone number listed on the inside back cover. As an immediate precautionary measure, isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids. Keep unauthorized personnel away. Stay upwind. Keep out of low areas.

/GUIDE 151: SUBSTANCES - TOXIC (Non-combustible)/ Protective Clothing: Wear positive pressure self-contained breathing apparatus (SCBA). Wear chemical protective clothing that is specifically recommended by the manufacturer. It may provide little or no thermal protection. Structural firefighters' protective clothing provides limited protection in fire situations ONLY; it is not effective in spill situations where direct contact with the substance is possible.

For more DOT Emergency Guidelines (Complete) data for DIMETHYLARSENIC ACID (8 total), please visit the HSDB record page.

UN 1572; Cacodylic acid

IMO 6.1; Cacodylic acid

49 215 57; Cacodylic acid

No person may /transport,/ offer or accept a hazardous material for transportation in commerce unless that person is registered in conformance ... and the hazardous material is properly classed, described, packaged, marked, labeled, and in condition for shipment as required or authorized by ... /the hazardous materials regulations (49 CFR 171-177)./

The International Air Transport Association (IATA) Dangerous Goods Regulations are published by the IATA Dangerous Goods Board pursuant to IATA Resolutions 618 and 619 and constitute a manual of industry carrier regulations to be followed by all IATA Member airlines when transporting hazardous materials.

The International Maritime Dangerous Goods Code lays down basic principles for transporting hazardous chemicals. Detailed recommendations for individual substances and a number of recommendations for good practice are included in the classes dealing with such substances. A general index of technical names has also been compiled. This index should always be consulted when attempting to locate the appropriate procedures to be used when shipping any substance or article.