(+-)-2-(3-Chlorophenoxy)propionic acid

The maximum degradation rate of 2-(3-chlorophenoxy)propionic acid, present at 40-45 mg/L, using an activated sludge from a municipal wastewater treatment plant and an ultimate biodegradability test, ISO 7287, was 12 and 18 umol/hr, following a 16-day lag phase and being completely removed after 25 days; the study was conducted using a racemic mixture of five chiral phenoxyalkanoic acids.

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational exposure or environmental contamination. Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in soil or water; effects on animal, aquatic, and plant life; and conformance with environmental and public health regulations.

Group I Containers: Combustible containers from organic or metallo-organic pesticides (except organic mercury, lead, cadmium, or arsenic compounds) should be disposed of in pesticide incinerators or in specified landfill sites. /Organic or metallo-organic pesticides/

Group II Containers: Non-combustible containers from organic or metallo-organic pesticides (except organic mercury, lead, cadmium, or arsenic compounds) must first be triple-rinsed. Containers that are in good condition may be returned to the manufacturer or formulator of the pesticide product, or to a drum reconditioner for reuse with the same type of pesticide product, if such reuse is legal under Department of Transportation regulations (eg 49 CFR 173.28). Containers that are not to be reused should be punctured ... and transported to a scrap metal facility for recycling, disposal or burial in a designated landfill. /Organic or metallo-organic pesticides/

For several good reasons, .... herbicides ... should be handled and applied only with full attention to safety measures that minimize personal contact. Many formulations contain adjuvants (stabilizers, penetrants, surfactants) that may have significant irritating and toxic effects. A number of premixed formulations contain two or more active ingredients; the companion pesticides may be more toxic than the principal herbicide. Good hygienic practice should not be disregarded just because a pesticide is reported to have a high LD50 in laboratory rodents.

SRP: The scientific literature for the use of contact lenses in industry is conflicting. The benefit or detrimental effects of wearing contact lenses depend not only upon the substance, but also on factors including the form of the substance, characteristics and duration of the exposure, the uses of other eye protection equipment, and the hygiene of the lenses. However, there may be individual substances whose irritating or corrosive properties are such that the wearing of contact lenses would be harmful to the eye. In those specific cases, contact lenses should not be worn. In any event, the usual eye protection equipment should be worn even when contact lenses are in place.

SRP: Contaminated protective clothing should be segregated in such a manner so that there is no direct personal contact by personnel who handle, dispose, or clean the clothing. Quality assurance to ascertain the completeness of the cleaning procedures should be implemented before the decontaminated protective clothing is returned for reuse by the workers. Contaminated clothing should not be taken home at end of shift, but should remain at employee's place of work for cleaning.

A tolerance is established for negligible residues of the plant regulator 2-(m-chlorophenoxy) propionic acid from application of the acid or of 2-(m-chlorophenoxy)propionamide in or on the following raw agricultural commodity: pineapple 0.3 ppm. Expiration/Revocation Date: 2/1/07

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 88(SRC), determined from a water solubility of 1,200 mg/L(2) and a regression-derived equation(3), indicates that 2-(3-chlorophenoxy)propionic acid is expected to have high mobility in soil(SRC). The estimated pKa of 2-(3-chlorophenoxy)propionic acid is 3.62(4), indicating that this compound will exit almost entirely in the anion form in the environment and anions generally do not adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts(5). Volatilization from moist soil is not expected because the acid exists as an anion and anions do not volatilize. 2-(3-Chlorophenoxy)propionic acid is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 2.3X10-4 mm Hg(SRC), determined from a fragment constant method(6). 2-(3-Chlorophenoxy)propionic acid was completely degraded in 25 days following a 16-day lag period using activated sludge(7), indicating that biodegradation may be an important environmental fate process in soil(SRC).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 88(SRC), determined from a water solubility of 1,200 mg/L(2) and a regression-derived equation(3), indicates that 2-(3-chlorophenoxy)propionic acid is not expected to adsorb to suspended solids and sediment(SRC). An estimated pKa of 3.62(4) indicates 2-(3-chlorophenoxy)propionic acid will exist almost entirely in the anion form at pH values of 5 to 9 and therefore volatilization from water surfaces is not expected to be an important fate process(5). According to a classification scheme(6), an estimated BCF of 11(SRC), from its water solubility(2) and a regression-derived equation(3), suggests the potential for bioconcentration in aquatic organisms is low(SRC). 2-(3-Chlorophenoxy)propionic acid was completely degraded in 25 days following a 16-day lag period using activated sludge(7), indicating that

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 2-(3-chlorophenoxy)propionic acid, which has an estimated vapor pressure of 2.3X10-4 mm Hg at 25 °C(SRC), determined from a fragment constant method(2), will exist solely as a vapor in the ambient atmosphere. Vapor-phase 2-(3-chlorophenoxy)propionic acid is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC); the half-life for this reaction in air is estimated to be 16 hours(SRC), calculated from its rate constant of 2.5X10-11 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). 2-(3-Chlorophenoxy)propionic acid contains chromophores that absorb at wavelengths >290 nm(4) and therefore may be susceptible to direct photolysis by sunlight(SRC).

Because dermal absorption is an important route of exposure to chlorophenoxy herbicides, biological monitoring is useful in estimating the absorbed dose. Urine concn provide the most accurate estimate of body burden; because of slow absorption, it is best to collect samples after a few days of exposure. /Chlorophenoxy herbicides/

The Koc of 2-(3-chlorophenoxy)propionic acid is estimated as 88(SRC), using a water solubility of 1,200 mg/L(1) and a regression-derived equation(2). According to a classification scheme(3), this estimated Koc value suggests that 2-(3-chlorophenoxy)propionic acid is expected to have high mobility in soil. The pKa of 2-(3-chlorophenoxy)propionic acid is 3.62(4), indicating that this compound will exist entirely in the anion form in the environment and anions generally do not adsorb) more strongly to soils containing organic carbon and clay than their neutral counterparts(5).

/SIGNS AND SYMPTOMS/ When ingested, high concentrations of chlorophenoxy compounds may irritate the mouth & throat, & GI tract. ... chest pain (from esophagitis), abdominal pain & diarrhea commonly ensue. ... absorbed chlorophenoxy compounds have caused fibrillary muscle twitching, skeletal muscle tenderness, & myotonia ... ingestion of very large amounts has produced metabolic acidosis, fever, tachycardia, hyperventilation, vasodilatation & sweating. Particular cases have been characterized by coma & convulsions. /Chlorophenoxy compounds/

/SIGNS AND SYMPTOMS/ Generally low systemic toxicity, May contain dioxins as contaminants, which have caused chloracne and neurologic damage to chemical plant workers; causes headache, dizziness. /Chlorophenoxy compounds; from table/

/SIGNS AND SYMPTOMS/ Workers involved in the manufacture of this class of herbicides, ... experienced a severe type of contact dermatitis called "chemical worker chloroacne." Herbicide sprayers of a few decades ago developed a persistent condition known as "weed bumps" /SRP: probably due to dioxin contamination/ following daily and seasonal exposure to chlorophenoxy herbicides. /Chlorophenoxy compound/

/SIGNS AND SYMPTOMS/ Ingestion of large amounts of chlorophenoxy acids has resulted in severe metabolic acidosis in humans. Such cases have been associated with electrocardiographic changes, myotonia, muscle weakness, myoglobinuria, and elevated serum creatine phosphokinase, all reflecting injury to striated muscle. Because chlorophenoxy acids are weak uncouplers of oxidative phosphorylation, extraordinary doses may produce hyperthermia from increased production of body heat. /Chlorophenoxy acids/

For more Human Toxicity Excerpts (Complete) data for 2-(3-CHLOROPHENOXY)PROPIONIC ACID (14 total), please visit the HSDB record page.

AEROBIC: The maximum degradation rate of 2-(3-chlorophenoxy)propionic acid, present at 40-45 mg/L, using an activated sludge from a municipal wastewater treatment plant and an ultimate biodegradability test, ISO 7287, was 12 and 18 umol/hr, following a 16-day lag phase and being completely removed after 25 days; the study was conducted using a racemic mixture of five chiral phenoxyalkanoic acids(1).

The rapid microbial hydrolysis of phenoxyalkanoic esters ... /has been observed/ on a variety of soils. /Phenoxyalkanoic esters/

An estimated BCF of 11 was calculated in fish for 2-(3-chlorophenoxy)propionic acid(SRC), using water solubility of 1,200 mg/L(1) and a regression-derived equation(2). According to a classification scheme(3), this BCF suggests the potential for bioconcentration in aquatic organisms is low(SRC).

An estimated pKa of 3.62(1) indicates 2-(3-chlorophenoxy)propionic acid will exist almost entirely in the anion form at pH values of 5 to 9 and therefore volatilization from water surfaces or moist soil is not expected to be an important fate process(2). 2-(3-Chlorophenoxy)propionic acid is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 2.3X10-4 mm Hg at 25 °C(SRC), determined from a fragment constant method(3).

Classification of carcinogenicity: 1) evidence in humans: limited; Overall summary evaluation of carcinogenic risk to humans is Group 2B: The agent is possibly carcinogenic to humans /SRP: Title compound has not been studied/.. /Chlorophenoxy herbicides; From table/

A tolerance is established for negligible residues of the plant regulator 2-(m-chlorophenoxy) propionic acid from application of the acid or of 2-(m-chlorophenoxy)propionamide in or on the following raw agricultural commodity: pineapple. Expiration/Revocation Date: 2/1/07

As the federal pesticide law FIFRA directs, EPA is conducting a comprehensive review of older pesticides to consider their health and environmental effects and make decisions about their future use. Under this pesticide reregistration program, EPA examines health and safety data for pesticide active ingredients initially registered before November 1, 1984, and determines whether they are eligible for reregistration. In addition, all pesticides must meet the new safety standard of the Food Quality Protection Act of 1996. Pesticides for which EPA had not issued Registration Standards prior to the effective date of FIFRA '88 were divided into three lists based upon their potential for human exposure and other factors, with List B containing pesticides of greater concern and List D pesticides of less concern. 2-(3-Chlorophenoxy) propionic acid is found on List B. Case No: 2110; Pesticide type: Herbicide Case Status: The last registered pesticide products containing this pesticide were voluntarily cancelled September 1996 by their registrants while the EPA was developing the RED; Active ingredient (AI): 2-(m-Chlorophenoxy)propionic acid; AI Status: The active ingredient is no longer contained in any registered products. Thus, we characterize it as "cancelled.".

EPA is issuing a notice of receipt of request by registrants to voluntarily cancel certain pesticide registrations ... . Unless a request is withdrawn all cancellations will be effective 12/18/90 ... . Active ingredients which would disappear as a result of registrants request to cancel. ... 2-(m-Chlorophenoxy)propionic acid.