Demeton-S

  • O,O-Diethyl S-2-ethylthioethyl phosphorothioate
Formula
C8H19O3PS2
Structure
Description
Colorless oil.
Uses
Agricultural insecticide, acaricide.

Registry Numbers and Inventories.
CAS
126-75-0
EC (EINECS/ELINCS)
204-801-8
EC Index Number
015-029-00-4
EC Class
Very toxic
RTECS
TF3130000
RTECS class
Agricultural Chemical and Pesticide; Drug
UN (DOT)
3018
Beilstein/Gmelin
1709166
Beilstein Reference
4-01-00-02461
EPA OPP
57603

Properties.
Formula
C8H19O3PS2
Formula mass
258.36
Melting point, °C
95 - 97
Boiling point, °C
320
Vapor pressure, mmHg
0.0006 (25 C)
Density
1.1346 g/cm3 (20 C)
Solubility in water
2 g/L
Refractive index
1.5 (18 C)
Partition coefficient, pKow
2.63
Heat of vaporization
54.0 kJ/mol

Hazards and Protection.
Storage
Keep in a cool, dry, dark location in a tightly sealed container or cylinder. Keep away from incompatible materials, ignition sources and untrained individuals. Secure and label area. Protect containers/cylinders from physical damage.
Handling
All chemicals should be considered hazardous. Avoid direct physical contact. Use appropriate, approved safety equipment. Untrained individuals should not handle this chemical or its container. Handling should occur in a chemical fume hood.
Protection
Protective gloves and clothing. Face shield.
Respirators
Wear positive pressure self-contained breathing apparatus (SCBA).
Small spills/leaks
Do not touch damaged containers or spilled material unless wearing appropriate protective clothing. Stop leak if you can do it without risk. 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.
Stability
Thin films undergo conversion to more hydrophilic compounds when exposed to air and light.

Fire.
Flash Point,°C
147
Fire fighting
Small Fires: Dry chemical, carbon dioxide or water spray. Large Fires: Water spray, fog or regular foam.
Fire potential
Combustible material: may burn but does not ignite readily.
Hazards
Containers may explode when heated.
Combustion products
Fire may produce irritating, corrosive and/or toxic gases.

Health.
Exposure limit(s)
TLV: 0.01 ppm; 0.1 mg/m3 (skin) (ACGIH 1992-1993)
Exposure effects
Fever, low heart rate and abnormally low blood pressure, or rapid heart rate and elevated blood pressure may occur. Headache, dizziness, muscle spasms and profound weakness are common. Alterations of level of consciousness, anxiety, paralysis, seizures and coma may occur. Seizures may be more common in children.
   Ingestion
Vomiting, diarrhea, fecal incontinence, pancreatitis and abdominal pain may occur.
   Inhalation
Dyspnea, rales, bronchorrhea, or tachypnea may occur, with pulmonary edema in severe cases.
   Skin
Sweating is a consistent but not universal sign.
   Eyes
Constriction of the pupil, tearing, blurred vision and salivation are common. Prolonged dialation of the pupils may occur in severe poisonings.

First aid
 
   Ingestion
Seek medical assistance.
   Inhalation
Move patient to fresh air. Monitor for respiratory distress. If cough or difficulty breathing develops, evaluate for respiratory tract irritation, bronchitis, or pneumonitis. Administer oxygen and assist ventilation as required. Treat bronchospasm with beta2 agonist and corticosteroid aerosols.
   Skin
Systemic effects can occur from dermal exposure to organophosphates. Remove contaminated clothing, wash skin, hair and nails vigorously with repeated soap washings. Leather absorbs pesticides; all contaminated leather should be discarded. Rescue personnel and bystanders should avoid direct contact with contaminated skin, clothing, or other objects. Treatment should include recommendations listed in the oral exposure section when appropriate. Some chemicals can produce systemic poisoning by absorption through intact skin. Carefully observe patients with dermal exposure for the development of any systemic signs or symptoms and administer symptomatic treatment as necessary. Contraindications - succinylcholine and other cholinergic agents are contraindicated.
   Eyes
Irrigate exposed eyes with copious amounts of tepid water for at least 15 minutes. If irritation, pain, swelling, lacrimation, or photophobia persist, the patient should be seen in a health care facility. Patients symptomatic following exposure should be observed in a controlled setting until all signs and symptoms have fully resolved. Suction oral secretions until atropinization. Treatment should include recommendations listed in the oral exposure section when appropriate. Contraindications - succinylcholine and other cholinergic agents are contraindicated.

Transport.
UN number
3018
Response guide
Hazard class
6.1
Packing Group
I; II; III