Ethyl methyl phosphorodithioate

  • Phosphorodithioic acid, O,O-diethyl S-methyl ester
  • O,O-Diethyl S-methyl phosphorodithioate

Registry Numbers and Inventories.
RTECS class
Agricultural Chemical and Pesticide
Beilstein Reference

Formula mass
Boiling point, °C
48 (0.01 torr)
1.1899 g/cm3 (20 C)
Solubility in water
Refractive index
1.5123 (14 C)

Hazards and Protection.
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.
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.
Chemical splash goggles in compliance with OSHA regulations are advised; however, OSHA regulations also permit other type safety glasses. Whre chemical resistant gloves. To prevent repeated or prolonged skin contact, wear impervious clothing and boots.
Respiratory protection (supplied-air respirator with full facepiece or self-contained breathing apparatus) should be available where these compounds are manufactured or used and should be worn in case of emergency and overexposure.
Small spills/leaks
Evacuate area and ventilate. Wear protective equipment. If required, use an inert absrobent. Sweep up and place in an appropriate container for disposal. Wash contaminated surfaces.
No data.
Strong oxidizing agents.

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 agent most appropriate to extinguish fire.
Combustion products
When heated to decomp, can emit highly toxic fumes of oxides of phosphorous.

Exposure effects
Reduced body temperature or elevated body temperature may occur. Low heart rate and abnormally low blood pressure may develop after moderate to severe poisoning. Rapid heart rate, elevated blood pressure, and changes in respiratory rate may also occur. Early giddiness, anxiety headache, and restlessness followed by ataxia, drowsiness, and confusion are common with moderate to severe exposures. Sporadic reports of human birth defects related to organophosphates have not been fully verified.
Nausea, vomiting, abdominal cramps, and diarrhea are common muscarinic effects. Both painless and frank clinical pancreatitis have been reported.
Increased bronchial secretions, bronchospasm and dyspnea occur in moderate to severe exposures. Respiratory failure and non-cardiogenic pulmonary edema may occur with severe poisonings. Acute respiratory insufficiency is the main cause of death in acute poisonings. The hydrocarbon vehicle may cause chemical pneumonitis.
Profuse sweating is common. Pallor may be noted. Dermal sensitization has been reported.
Constriction of the pupil, tearing, and blurred vision are common. Prolonged dialation of the pupils may occur. Salivation commonly occurs.

First aid
Seek medical attention. If individual is drowsy or unconscious, do not give anything by mouth; place individual on the left side with the head down. Contact a physician, medical facility, or poison control center for advice about whether to induce vomiting. If possible, do not leave individual unattended.
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.
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.
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. Treatment should include recommendations listed in the oral exposure section when appropriate.