SPECTRUM

Chemical Fact Sheet

Chemical Abstract Number (CAS #) 101213
CASRN 101-21-3
SynonymsChlorpropham
Carbamic acid, (3-chlorophenyl)-, 1-methylethyl ester
CIPC
Isopropyl 3-chlorocarbanilate
Chloro-IPC
Furloe
Metoxon
Preventol
Analytical Method EPA Method 632
Molecular FormulaC10H12ClNO2

Link to the National Library of Medicine's Hazardous Substances
Database for more details on this compound.

Use CHLORPROPHAM ACTS AS HIGHLY SELECTIVE PREEMERGENCE & EARLY POSTEMERGENCE HERBICIDE; IT EFFECTIVELY CONTROLS MANY ANNUAL GRASSY & BROADLEAF WEEDS; APPLICATION DURING LATE FALL & WINTER FOR CONTROL OF SOME PERENNIAL WEEDS. FOR CONTROL OF WEEDS IN ALFALFA, LIMA & SNAP BEANS, BLUEBERRIES, CANE BERRIES, CRANBERRIES, CARROTS, LADINO CLOVER, GARLIC, SEED GRASS, PEAS, ONIONS, SPINACH, SUGAR BEETS, TOMATOES, SAFFLOWER, SOYBEANS, GLADIOLI, WOODY NURSERY STOCK. ALSO FOR INHIBITING POTATO SPROUTING AND SYSTEMIC SUCKER CONTROL IN TOBACCO.
Consumption Patterns HERBICIDE, OF WHICH APPROXIMATELY 82% IS USED ON SOYBEANS AND 18% ON VEGETABLES (1975)
Apparent Color HONEY COLOR ; LIQUID @ ROOM TEMP ; LIGHT BROWN CRYSTALLINE SOLID ; Light tan powder ; Faint characteristic odor
Odor VERY LITTLE ODOR
Boiling Point 149 DEG C AT 2 MM HG
Melting Point 40.7-41.1 DEG C
Molecular Weight 213.68
Density 1.180 @ 30 DEG C
Sensitivity Data Mild irritant.
Environmental Impact Chlorpropham is a herbicide used on several crops to control annual grasses and many broad-leaved weeds. The release of chlorpropham in the environment occurs during its manufacture and particularly from its use in the field. Chlorpropham adsorbs strongly to soil and clays and will exhibit low mobility in soil. In soil, chlorpropham is transformed primarily by biodegradation. The half-life of chlorpropham from field soil is about 30 days. If released in water, chlorpropham will adsorb strongly to sediment and particulate matter in the water column. Although a slow process, biodegradation should be the major pathway for degradation. Loss of chlorpropham due to hydrolysis, photolysis and volatilization should not be important loss processes. Chlorpropham will not bioconcentrate in aquatic organisms. In the atmosphere, chlorpropham will react with hydroxyl radicals with an estimated half-life of 5.5 hrs. Partial removal of atmospheric chlorpropham will also occur by dry and wet deposition. Chlorpropham has been infrequently detected in groundwater around sprayed farmlands. Workers who apply chlorpropham are the most likely people to be exposed to chlorpropham. Exposure would be expected by inhalation and dermal contact. The general population may be exposed to low levels of chlorpropham in food.
Environmental Fate TERRESTRIAL FATE: Biodegradation via enzymatic hydrolysis will be the major process by which chlorpropham will be lost from most soils . The loss of chlorpropham from soil due to photolysis on soil surface may not be important . Vaporization loss of chlorpropham from dry soil should be negligible, but increases with increase in temperature, moisture content and air flow rate . The leaching of chlorpropham from three types of soil was low and more than 90% of chlorpropham was found in the upper inch of the soil after 4 cm of rain . Depending on the nature of soil and climatic conditions, the field half-life of chlorpropham in soil range from less than 30 days to 65 days with an average half-life of 30 days . AQUATIC FATE: Based on a mean rate constant of 2.6X10-14 l/organism-hr and a bacterial concn of 5X10 8 organisms/l in water, the half-life of chlorpropham has been estimated to be 2208 days . Therefore, biodegradation of chlorpropham should not be important in clear bodies of water. However, biodegradation may become important if the bacterial population in water is several orders of magnitude higher than 10 8 organisms . The hydrolysis half-life of chlorpropham in the pH range 5-9 has been estimated to be greater than 10000 days . The estimated minimum half-life for the direct sunlight photolysis of chlorpropham in clear surface layers of water is 121 days . Based on the available data , it is concluded that biodegradation may be the dominant degradation pathway for chlorpropham in polluted waters, but photolysis may become the dominant degradative pathway in unpolluted waters. Based upon the moderate water solubility (89 ppm) and the low vapor pressure (7.5X10-6 mmHg) , chlorpropam should not volatilize from water or bioconcentrate in aquatic organisms(5,SRC). ATMOSPHERIC FATE: From its estimated vapor pressure of 7.5X10-6 mm Hg at 25 deg C(1,4), chlorpropham is expected to be present partially in the vapor phase and partially in the particulate form in air(2,SRC). Based on an estimation method(3,5), vapor phase chlorpropham should be removed from the atmosphere with an estimated half-life of 5.5 hrs due to reaction with photochemically produced hydroxyl radicals. Partial removal of particulate chlorpropham from the air may occur by dry deposition. Chlorpropham may also be washed out of the air by rain. MOIST SOIL TREATED WITH CHLOROPROPHAM TO GIVE CONCN OF 100 PPM AI WAS INCUBATED IN POLYETHYLENE BAGS @ 23 DEG C FOR 30 WK. CO2 EVOLUTION WAS DETERMINED WEEKLY. CHLOROPHAM WAS DEGRADED RAPIDLY IN FIRST 6WK & 5% OF ORIGINAL AMT COULD BE DETECTED 30 WK LATER.
Drinking Water Impact GROUNDWATER: Chlorpropham has been detected in one groundwater sample from 28 of California's 58 counties at a concn of 8.0 ug/l(1-3).

DISCLAIMER - Please Read

Florida-Spectrum List of Services
Florida-Spectrum Homepage