Cacodylic acid

  • Dimethylarsinic acid
  • Hydroxydimethylarsine oxide
  • Phytar
Formula
(CH3)2As(O)OH
Structure
Description
A colorless, odorless crystalline solid.
Uses
Arsenical herbicide.

Registry Numbers and Inventories.
CAS
75-60-5
EC (EINECS/ELINCS)
200-883-4
RTECS
CH7525000
RTECS class
Agricultural Chemical and Pesticide; Tumorigen; Drug; Organometallic; Mutagen; Reproductive Effector; Primary Irritant
UN (DOT)
1572
Merck
12,1640
Beilstein/Gmelin
1736965
Beilstein Reference
4-04-00-03681
RCRA
U136
EPA OPP
12501
Swiss Giftliste 1
G-2494
Canada DSL/NDSL
NDSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed

Properties.
Formula
C2H7AsO2
Formula mass
138
Boiling point, °C
253
Vapor pressure, mmHg
0.003 (25 C)
Odor Threshold Odor threshold Odorless
Density
> 1.1 (est)g/cm3 (20 C)
Solubility in water
830 g/L
pKa/pKb
6.30 (pKa)
Partition coefficient, pKow
-1.62
Heat of vaporization
57.0 kJ/mol
Heat of combustion
-1904 kJ/mol

Hazards and Protection.
Storage
Store in a tightly closed container. Store in a cool, dry, well-ventilated area away from incompatible substances.
Handling
Wash thoroughly after handling. Use only in a well ventilated area. Minimize dust generation and accumulation. Avoid contact with eyes, skin, and clothing. Keep container tightly closed. Avoid ingestion and inhalation.
Protection
Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear appropriate protective gloves to prevent skin exposure. Clothing: Wear appropriate protective clothing to prevent skin exposure.
Respirators
Follow the OSHA respirator regulations found in 29CFR 1910.134 or European Standard EN 149. Always use a NIOSH or European Standard EN 149 approved respirator when necessary.
Small spills/leaks
Vacuum or sweep up material and place into a suitable disposal container. Avoid runoff into storm sewers and ditches which lead to waterways. Clean up spills immediately, using the appropriate protective equipment. Avoid generating dusty conditions. Provide ventilation.
Stability
Stable at room temperature in closed containers under normal storage and handling conditions.
Incompatibilities
Strong oxidizing agents and strong bases.
Decomposition
Carbon monoxide, irritating and toxic fumes and gases, carbon dioxide, oxides of arsenic.

Fire.
Flash Point,°C
109
Fire fighting
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion. Use water spray to keep fire-exposed containers cool. Use extinguishing media appropriate to the surrounding fire. Substance is noncombustible. Containers may explode when heated. Runoff from fire control or dilution water may cause pollution. Extinguishing media: Do NOT get water inside containers. Do NOT use straight streams of water. For small fires, use dry chemical, carbon dioxide, or water spray. Cool containers with flooding quantities of water until well after fire is out. For large fires, use water spray, fog or regular foam. For large fires, flood fire area with water from a distance.
Fire potential
Nonflammable
Hazards
May form toxic oxides of arsenic when heated.
Combustion products
May form toxic oxides of arsenic when heated.
Health
2
 
Flammability
0
 
 
Reactivity
0
 

Health.
Exposure limit(s)
OSHA PEL: 1910.1018 TWA 0.010 mg/m3 NIOSH REL: Ca C 0.002 mg/m3 15-minute See Appendix A NIOSH IDLH: Potential occupational carcinogen 5 mg/m3 (as As)
Carcinogin
CP65
Poison_Class
3
Exposure effects
May cause cancer according to animal studies. Reproductive effects have been reported in animals. Chronic exposure to arsenical dust may cause breath shortness, nausea, chest pains, and garlic odor.
   Ingestion
May cause gastrointestinal irritation with nausea, vomiting and diarrhea. May be harmful if swallowed. Ingestion of arsenical compounds may cause burning of the lips, throat constriction, swallowing difficulties, severe abdominal pain, severe nausea, projectile vomiting, and profuse diarrhea. Ingestion of arsenic compounds can produce convulsions, coma, and possibly death within 24 hours.
   Inhalation
May cause respiratory tract irritation. Inhalation of arsenic compounds may lead to irritation of the respiratory tract and leading to possible nasal perforation. Long-term exposure to arsenic compounds may produce impairment of peripheral circulation.
   Skin
May cause skin irritation. May be absorbed through the skin in harmful amounts. Exposure to arsenic compounds may produce hyperpigmentation of the skin and hyperkeratoses of plantar and palmar surfacesas well as both primary irritation and sensitization types.
   Eyes
May cause eye irritation.

First aid
 
   Ingestion
Do NOT induce vomiting. If victim is conscious and alert, give 2-4 cupfuls of milk or water. Get medical aid.
   Inhalation
Remove from exposure to fresh air immediately. Get medical aid if cough or other symptoms appear. DO NOT use mouth-to-mouth respiration. If breathing has ceased apply artificial respiration using oxygen and a suitable mechanical device such as a bag and a mask.
   Skin
Flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Get medical aid if irritation develops or persists. Wash clothing before reuse.
   Eyes
Flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid.

Transport.
UN number
1572
Response guide
Hazard class
6.1
Packing Group
II
 
USCG CHRIS Code
CDA
 
Std. Transport #
4921557