- O,O-Diethyl O-3,5,6-trichloro-2-pyridyl phosphorothioate
Chlorpyrifos is a white crystalline or irregularly flaked solid. It has a very faint mercaptan-type odor.
Acaricide, insecticide, nematicide.
Registry Numbers and Inventories.
EC Index Number
Toxic; Dangerous for the Environment
Agricultural Chemical and Pesticide; Drug; Mutagen; Reproductive Effector; Human Data
Swiss Giftliste 1
Japan ENCS (MITI)
Melting point, °C
Boiling point, °C
Decomposition point, °C
Vapor pressure, mmHg
2E-5 (25 C)
1.40 g/cm3 (20 C)
Solubility in water
Partition coefficient, pKow
Heat of vaporization
Hazards and Protection.
Tightly closed containers. Keep away from heat and water.
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.
Wear appropriate chemical protective gloves, boots and goggles. Wear appropriate eye protection and protective clothing to prevent skin and eye contact.
Wear positive pressure self-contained breathing apparatus (SCBA).
Keep sparks, flames, and other sources of ignition away. Keep material out of water sources and sewers. Land spill: Dig a pit, pond, lagoon, holding area to contain liquid or solid material. Cover solids with a plastic sheet to prevent dissolving in rain or fire fighting water. Dike surface flow using soil, sand bags, foamed polyurethane, or foamed concrete. Water spill: Use natural barriers or oil spill control booms to limit spill travel. Use natural deep water pockets, excavated lagoons, or sand bag barriers to trap material at bottom. Remove trapped material with suction hoses.
Very stable under neutral or slightly acid conditions at room temperature.
Sensitive to heat and is decomposed by moisture It is
Decomposition temperature: approx 160 C when heated to decomposition it emits very toxic fumes of cl-, oxides of nitrogen, phosphoxides and sulfoxides.
Use water in flooding quantities as fog. Extinguish fire using agent suitable for type of surrounding fire. (Material itself does not burn or burns with difficulty.) Use foam, dry chemical, or carbon dioxide.
May burn but does not ignite readily.
Containers may explode when heated. Runoff may pollute waterways. Substance may be transported in a molten form.
Fire may produce irritating, corrosive and/or toxic gases.
TLV: ppm; 0.2 mg/m3 (skin) (ACGIH 1991-1992). NIOSH REL: TWA 0.2 mg/m3 ST 0.6 mg/m3 skin
Headache, dizziness, muscle spasms and profound weakness are common. Seizures may be more common in children. Delayed neurotoxicity occurred in the standard hen assay, but the effects were reversible. There is one case in the clinical literature of delayed peripheral neurotoxicity in an acute overdose. Chlorpyrifos did not induce delayed neurotoxicity in mice. It was not teratogenic and had no other effects on fertility in rats. <br>It has been detected in cow's milk. <br>Sporadic reports of human birth defects related to organophosphates have not been fully verified.
Vomiting, diarrhea, fecal incontinence and abdominal pain may occur.
Dyspnea, rales, bronchorrhea, or tachypnea may be noted. Pulmonary edema may occur in severe cases.
Irritation and slight burns may occur.
Mydriasis may occur in severe poisonings. Opsoclonus has occurred rarely. Excessive salivation commonly occurs.
If the victim is conscious and not convulsing, give 1 or 2 glasses of water to dilute the chemical and IMMEDIATELY call a hospital or poison control center. Be prepared to transport the victim to a hospital if advised by a physician.
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.
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.
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.
I; II; III
USCG CHRIS Code
Std. Transport #