Chlorpyrifos

  • O,O-Diethyl O-3,5,6-trichloro-2-pyridyl phosphorothioate
  • Clorpyrifos
  • Dursban
  • Lorsban
Formula
C9H11Cl3NO3PS
Structure
Description
Chlorpyrifos is a white crystalline or irregularly flaked solid. It has a very faint mercaptan-type odor.
Uses
Acaricide, insecticide, nematicide.

Registry Numbers and Inventories.
CAS
2921-88-2
EC (EINECS/ELINCS)
220-864-4
EC Index Number
015-084-00-4
EC Class
Toxic; Dangerous for the Environment
RTECS
TF6300000
RTECS class
Agricultural Chemical and Pesticide; Drug; Mutagen; Reproductive Effector; Human Data
UN (DOT)
2783
Merck
12,2242
Beilstein/Gmelin
1545756
EPA OPP
59101
Swiss Giftliste 1
G-3670
Canada DSL/NDSL
DSL
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
C9H11Cl3NO3PS
Formula mass
350.59
Melting point, °C
41-42
Boiling point, °C
276
Decomposition point, °C
160
Vapor pressure, mmHg
2E-5 (25 C)
Density
1.40 g/cm3 (20 C)
Solubility in water
2 mg/L
Partition coefficient, pKow
5.27
Heat of vaporization
59.9 kJ/mol

Hazards and Protection.
Storage
Tightly closed containers. Keep away from heat and water.
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
Wear appropriate chemical protective gloves, boots and goggles. Wear appropriate eye protection and protective clothing to prevent skin and eye contact.
Respirators
Wear positive pressure self-contained breathing apparatus (SCBA).
Small spills/leaks
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.
Stability
Very stable under neutral or slightly acid conditions at room temperature.
Incompatibilities
Sensitive to heat and is decomposed by moisture It is
Decomposition
Decomposition temperature: approx 160 C when heated to decomposition it emits very toxic fumes of cl-, oxides of nitrogen, phosphoxides and sulfoxides.

Fire.
Flash Point,°C
181
Fire fighting
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.
Fire potential
May burn but does not ignite readily.
Hazards
Containers may explode when heated. Runoff may pollute waterways. Substance may be transported in a molten form.
Combustion products
Fire may produce irritating, corrosive and/or toxic gases.

Health.
Exposure limit(s)
TLV: ppm; 0.2 mg/m3 (skin) (ACGIH 1991-1992). NIOSH REL: TWA 0.2 mg/m3 ST 0.6 mg/m3 skin
Poison_Class
3
Exposure effects
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.
   Ingestion
Vomiting, diarrhea, fecal incontinence and abdominal pain may occur.
   Inhalation
Dyspnea, rales, bronchorrhea, or tachypnea may be noted. Pulmonary edema may occur in severe cases.
   Skin
Irritation and slight burns may occur.
   Eyes
Mydriasis may occur in severe poisonings. Opsoclonus has occurred rarely. Excessive salivation commonly occurs.

First aid
 
   Ingestion
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.
   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.
   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.
   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.

Transport.
UN number
2783
Response guide
Hazard class
6.1
Packing Group
I; II; III
 
USCG CHRIS Code
DUR
 
Std. Transport #
4925315