Mecoprop

  • 2-(4-Chloro-o-tolyloxy)propionic acid
  • 2-(4-Chloro-2-methylphenoxy)propanoic acid
  • MCPP
Formula
C10H11ClO3
Structure
Description
Colorless crystals.
Uses
Selective herbicide for post-emergence control of broad-leaved weeds in wheat, barley, oats, herbage seed crops, grassland, and under fruit trees and vines, and control of docks in meadow and pastures.

Registry Numbers and Inventories.
CAS
93-65-2
EC (EINECS/ELINCS)
202-264-4
EC Index Number
607-049-00-2
EC Class
Harmful; Irritant
R 22 38 41
S 26 37/39
RTECS
UE9750000
RTECS class
Agricultural Chemical and Pesticide; Tumorigen; Mutagen; Reproductive Effector
UN (DOT)
2765
Merck
13,5807
Beilstein/Gmelin
2212752
Beilstein Reference
3-06-00-01266
Swiss Giftliste 1
G-2391
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed

Properties.
Formula
C10H11ClO3
Formula mass
214.66
Melting point, °C
92 - 94
Boiling point, °C
327
Vapor density (air=1)
N/R
Critical temperature
530
Critical pressure
29.3
Density
1.35 g/cm3
Solubility in water
600 mg/L
pKa/pKb
3.20 (pKa)
Partition coefficient, pKow
3.13

Hazards and Protection.
Storage
Do not store near heat or open flame. Protect from freezing. Storage site should be close to lab so that only small quantities required for experimentation need to be carried. Carcinogens should be kept in only one section of storage area, explosion-proof refrigerator or freezer as required. The area should be appropriately labeled. An inventory should be kept showing the quantity of carcinogen and date it was acquired. Facilities for dispensing should be contiguous to storage area.
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
Dispensers of liquid detergent should be available. In the laboratory, gloves and protective clothing should always be worn but should not be assumed to provide full protection. Carefully fitted masks or respirators may be necessary when working with particulates or gases, and disposable plastic aprons might provide additional protection. Protective clothing should be of distinctive color, as a reminder not to be worn outside the laboratory.
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
It is stable to heat and resistant to redn, hydrolysis, atmospheric oxidn. Solutions of the salt of mcpp are stable for several yr under normal storage conditions. At low temperatures the salt will crystallize out of solution, but the crystals will redissolve on warming. Salts of mecoprop.
Incompatibilities
Strong oxidizing agents.
Decomposition
May give off chlorine compounds and carbon monoxide.

Fire.
Fire fighting
Small Fires: Dry chemical, carbon dioxide or water spray. Large Fires: Water spray, fog or regular foam.
Fire potential
Pure mecoprop as well as commercial products are nonflammable.
Hazards
Containers may explode when heated.
Combustion products
Fire may produce irritating, corrosive and/or toxic gases.

Health.
Poison_Class
4
Exposure effects
Low dose exposures - vertigo, headache, malaise, and paresthesias may occur depending on the specific compound involved. High dose exposures - muscle twitching, spasms, profound weakness, polyneuritis, and unconsciousness may occur depending on the specific compound involved. Idiosyncratic reactions - peripheral neuropathies 2,4-D and 2,4,5-T have caused adverse reproductive effects in experimental animals. Allegations of human birth defects due to these compounds have not been confirmed.
   Ingestion
Nausea, vomiting, and diarrhea have been reported. Necrosis of the gastrointestinal mucosa has been reported.
   Inhalation
Ingestion of large amounts may cause bradypnea, respiratory failure, hyperventilation, or pulmonary edema.
   Skin
Direct contact may cause skin irritation. Chlorodioxin contamination of products may produce chloracne with heavy exposure.
   Eyes
Eye, nose, and mouth irritation are possible with direct contact.

First aid
 
   Ingestion
Induce vomiting with Ipecac syrup. Seek medical advice.
   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
Remove contaminated clothing and jewelry. Wash the skin, including hair and nails, vigorously; do repeated soap washings. Discard contaminated clothing. Treat dermal irritation or burns with standard topical therapy. Patients developing dermal hypersensitivity reactions may require treatment with systemic or topical corticosteroids or antihistamines.
   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.

Transport.
UN number
2765
Response guide
Hazard class
3.2